Increase the number of road and tram subtypes to 32.

[openttd-joker.git] / src / newgrf.cpp

/* $Id: newgrf.cpp 26245 2014-01-12 18:01:50Z frosch $ */

/*
 * This file is part of OpenTTD.
 * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
 * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
 */

/** @file newgrf.cpp Base of all NewGRF support. */

#include "stdafx.h"

#include <stdarg.h>
#include <algorithm>

#include "debug.h"
#include "fileio_func.h"
#include "engine_func.h"
#include "engine_base.h"
#include "bridge.h"
#include "town.h"
#include "newgrf_engine.h"
#include "newgrf_text.h"
#include "fontcache.h"
#include "currency.h"
#include "landscape.h"
#include "newgrf_cargo.h"
#include "newgrf_house.h"
#include "newgrf_sound.h"
#include "newgrf_station.h"
#include "industrytype.h"
#include "newgrf_canal.h"
#include "newgrf_townname.h"
#include "newgrf_industries.h"
#include "newgrf_airporttiles.h"
#include "newgrf_airport.h"
#include "newgrf_object.h"
#include "rev.h"
#include "fios.h"
#include "strings_func.h"
#include "date_func.h"
#include "string_func.h"
#include "network/network.h"
#include <map>
#include "smallmap_gui.h"
#include "genworld.h"
#include "error.h"
#include "vehicle_func.h"
#include "language.h"
#include "vehicle_base.h"

#include "table/strings.h"
#include "table/build_industry.h"

#include "3rdparty/cpp-btree/btree_map.h"

#include "safeguards.h"

/* TTDPatch extended GRF format codec
 * (c) Petr Baudis 2004 (GPL'd)
 * Changes by Florian octo Forster are (c) by the OpenTTD development team.
 *
 * Contains portions of documentation by TTDPatch team.
 * Thanks especially to Josef Drexler for the documentation as well as a lot
 * of help at #tycoon. Also thanks to Michael Blunck for his GRF files which
 * served as subject to the initial testing of this codec. */

/** List of all loaded GRF files */
static SmallVector<GRFFile *, 16> _grf_files;

/** Miscellaneous GRF features, set by Action 0x0D, parameter 0x9E */
byte _misc_grf_features = 0;

/** 32 * 8 = 256 flags. Apparently TTDPatch uses this many.. */
static uint32 _ttdpatch_flags[8];

/** Indicates which are the newgrf features currently loaded ingame */
GRFLoadedFeatures _loaded_newgrf_features;

static const uint MAX_SPRITEGROUP = UINT8_MAX; ///< Maximum GRF-local ID for a spritegroup.

/** Temporary data during loading of GRFs */
struct GrfProcessingState {
private:
        /** Definition of a single Action1 spriteset */
        struct SpriteSet {
                SpriteID sprite;  ///< SpriteID of the first sprite of the set.
                uint num_sprites; ///< Number of sprites in the set.
        };

        /** Currently referenceable spritesets */
        btree::btree_map<uint, SpriteSet> spritesets[GSF_END];

public:
        /* Global state */
        GrfLoadingStage stage;    ///< Current loading stage
        SpriteID spriteid;        ///< First available SpriteID for loading realsprites.

        /* Local state in the file */
        uint file_index;          ///< File index of currently processed GRF file.
        GRFFile *grffile;         ///< Currently processed GRF file.
        GRFConfig *grfconfig;     ///< Config of the currently processed GRF file.
        uint32 nfo_line;          ///< Currently processed pseudo sprite number in the GRF.
        byte grf_container_ver;   ///< Container format of the current GRF file.

        /* Kind of return values when processing certain actions */
        int skip_sprites;         ///< Number of psuedo sprites to skip before processing the next one. (-1 to skip to end of file)

        /* Currently referenceable spritegroups */
        SpriteGroup *spritegroups[MAX_SPRITEGROUP + 1];

        /** Clear temporary data before processing the next file in the current loading stage */
        void ClearDataForNextFile()
        {
                this->nfo_line = 0;
                this->skip_sprites = 0;

                for (uint i = 0; i < GSF_END; i++) {
                        this->spritesets[i].clear();
                }

                memset(this->spritegroups, 0, sizeof(this->spritegroups));
        }

        /**
         * Records new spritesets.
         * @param feature GrfSpecFeature the set is defined for.
         * @param first_sprite SpriteID of the first sprite in the set.
         * @param first_set First spriteset to define.
         * @param numsets Number of sets to define.
         * @param numents Number of sprites per set to define.
         */
        void AddSpriteSets(byte feature, SpriteID first_sprite, uint first_set, uint numsets, uint numents)
        {
                assert(feature < GSF_END);
                for (uint i = 0; i < numsets; i++) {
                        SpriteSet &set = this->spritesets[feature][first_set + i];
                        set.sprite = first_sprite + i * numents;
                        set.num_sprites = numents;
                }
        }

        /**
         * Check whether there are any valid spritesets for a feature.
         * @param feature GrfSpecFeature to check.
         * @return true if there are any valid sets.
         * @note Spritesets with zero sprites are valid to allow callback-failures.
         */
        bool HasValidSpriteSets(byte feature) const
        {
                assert(feature < GSF_END);
                return !this->spritesets[feature].empty();
        }

        /**
         * Check whether a specific set is defined.
         * @param feature GrfSpecFeature to check.
         * @param set Set to check.
         * @return true if the set is valid.
         * @note Spritesets with zero sprites are valid to allow callback-failures.
         */
        bool IsValidSpriteSet(byte feature, uint set) const
        {
                assert(feature < GSF_END);
                return this->spritesets[feature].find(set) != this->spritesets[feature].end();
        }

        /**
         * Returns the first sprite of a spriteset.
         * @param feature GrfSpecFeature to query.
         * @param set Set to query.
         * @return First sprite of the set.
         */
        SpriteID GetSprite(byte feature, uint set) const
        {
                assert(IsValidSpriteSet(feature, set));
                return this->spritesets[feature].find(set)->second.sprite;
        }

        /**
         * Returns the number of sprites in a spriteset
         * @param feature GrfSpecFeature to query.
         * @param set Set to query.
         * @return Number of sprites in the set.
         */
        uint GetNumEnts(byte feature, uint set) const
        {
                assert(IsValidSpriteSet(feature, set));
                return this->spritesets[feature].find(set)->second.num_sprites;
        }
};

static GrfProcessingState _cur;


/**
 * Helper to check whether an image index is valid for a particular NewGRF vehicle.
 * @param <T> The type of vehicle.
 * @param image_index The image index to check.
 * @return True iff the image index is valid, or 0xFD (use new graphics).
 */
template <VehicleType T>
static inline bool IsValidNewGRFImageIndex(uint8 image_index)
{
        return image_index == 0xFD || IsValidImageIndex<T>(image_index);
}

class OTTDByteReaderSignal { };

/** Class to read from a NewGRF file */
class ByteReader {
protected:
        byte *data;
        byte *end;

public:
        ByteReader(byte *data, byte *end) : data(data), end(end) { }

        inline byte ReadByte()
        {
                if (data < end) return *(data)++;
                throw OTTDByteReaderSignal();
        }

        uint16 ReadWord()
        {
                uint16 val = ReadByte();
                return val | (ReadByte() << 8);
        }

        uint16 ReadExtendedByte()
        {
                uint16 val = ReadByte();
                return val == 0xFF ? ReadWord() : val;
        }

        uint32 ReadDWord()
        {
                uint32 val = ReadWord();
                return val | (ReadWord() << 16);
        }

        uint32 ReadVarSize(byte size)
        {
                switch (size) {
                        case 1: return ReadByte();
                        case 2: return ReadWord();
                        case 4: return ReadDWord();
                        default:
                                NOT_REACHED();
                                return 0;
                }
        }

        const char *ReadString()
        {
                char *string = reinterpret_cast<char *>(data);
                size_t string_length = ttd_strnlen(string, Remaining());

                if (string_length == Remaining()) {
                        /* String was not NUL terminated, so make sure it is now. */
                        string[string_length - 1] = '\0';
                        grfmsg(7, "String was not terminated with a zero byte.");
                } else {
                        /* Increase the string length to include the NUL byte. */
                        string_length++;
                }
                Skip(string_length);

                return string;
        }

        inline size_t Remaining() const
        {
                return end - data;
        }

        inline bool HasData(size_t count = 1) const
        {
                return data + count <= end;
        }

        inline byte *Data()
        {
                return data;
        }

        inline void Skip(size_t len)
        {
                data += len;
                /* It is valid to move the buffer to exactly the end of the data,
                 * as there may not be any more data read. */
                if (data > end) throw OTTDByteReaderSignal();
        }
};

typedef void (*SpecialSpriteHandler)(ByteReader *buf);

static const uint NUM_STATIONS_PER_GRF = 255; ///< Number of StationSpecs per NewGRF; limited to 255 to allow extending Action3 with an extended byte later on.

/** Temporary engine data used when loading only */
struct GRFTempEngineData {
        /** Summary state of refittability properties */
        enum Refittability {
                UNSET    =  0,  ///< No properties assigned. Default refit masks shall be activated.
                EMPTY,          ///< GRF defined vehicle as not-refittable. The vehicle shall only carry the default cargo.
                NONEMPTY,       ///< GRF defined the vehicle as refittable. If the refitmask is empty after translation (cargotypes not available), disable the vehicle.
        };

        uint16 cargo_allowed;
        uint16 cargo_disallowed;
        RailTypeLabel railtypelabel;
        uint8 roadsubtype;
        const GRFFile *defaultcargo_grf; ///< GRF defining the cargo translation table to use if the default cargo is the 'first refittable'.
        Refittability refittability;     ///< Did the newgrf set any refittability property? If not, default refittability will be applied.
        bool prop27_set;         ///< Did the NewGRF set property 27 (misc flags)?
        uint8 rv_max_speed;      ///< Temporary storage of RV prop 15, maximum speed in mph/0.8
        uint32 ctt_include_mask; ///< Cargo types always included in the refit mask.
        uint32 ctt_exclude_mask; ///< Cargo types always excluded from the refit mask.

        /**
         * Update the summary refittability on setting a refittability property.
         * @param non_empty true if the GRF sets the vehicle to be refittable.
         */
        void UpdateRefittability(bool non_empty)
        {
                if (non_empty) {
                        this->refittability = NONEMPTY;
                } else if (this->refittability == UNSET) {
                        this->refittability = EMPTY;
                }
        }
};

static GRFTempEngineData *_gted;  ///< Temporary engine data used during NewGRF loading

/**
 * Contains the GRF ID of the owner of a vehicle if it has been reserved.
 * GRM for vehicles is only used if dynamic engine allocation is disabled,
 * so 256 is the number of original engines. */
static uint32 _grm_engines[256];

/** Contains the GRF ID of the owner of a cargo if it has been reserved */
static uint32 _grm_cargoes[NUM_CARGO * 2];

struct GRFLocation {
        uint32 grfid;
        uint32 nfoline;

        GRFLocation() { }
        GRFLocation(uint32 grfid, uint32 nfoline) : grfid(grfid), nfoline(nfoline) { }

        bool operator<(const GRFLocation &other) const
        {
                return this->grfid < other.grfid || (this->grfid == other.grfid && this->nfoline < other.nfoline);
        }

        bool operator == (const GRFLocation &other) const
        {
                return this->grfid == other.grfid && this->nfoline == other.nfoline;
        }
};

static btree::btree_map<GRFLocation, SpriteID> _grm_sprites;
typedef btree::btree_map<GRFLocation, byte*> GRFLineToSpriteOverride;
static GRFLineToSpriteOverride _grf_line_to_action6_sprite_override;

/**
 * DEBUG() function dedicated to newGRF debugging messages
 * Function is essentially the same as DEBUG(grf, severity, ...) with the
 * addition of file:line information when parsing grf files.
 * NOTE: for the above reason(s) grfmsg() should ONLY be used for
 * loading/parsing grf files, not for runtime debug messages as there
 * is no file information available during that time.
 * @param severity debugging severity level, see debug.h
 * @param str message in printf() format
 */
void CDECL grfmsg(int severity, const char *str, ...)
{
        char buf[1024];
        va_list va;

        va_start(va, str);
        vseprintf(buf, lastof(buf), str, va);
        va_end(va);

        DEBUG(grf, severity, "[%s:%d] %s", _cur.grfconfig->filename, _cur.nfo_line, buf);
}

/**
 * Obtain a NewGRF file by its grfID
 * @param grfid The grfID to obtain the file for
 * @return The file.
 */
static GRFFile *GetFileByGRFID(uint32 grfid)
{
        const GRFFile * const *end = _grf_files.End();
        for (GRFFile * const *file = _grf_files.Begin(); file != end; file++) {
                if ((*file)->grfid == grfid) return *file;
        }
        return nullptr;
}

/**
 * Obtain a NewGRF file by its filename
 * @param filename The filename to obtain the file for.
 * @return The file.
 */
static GRFFile *GetFileByFilename(const char *filename)
{
        const GRFFile * const *end = _grf_files.End();
        for (GRFFile * const *file = _grf_files.Begin(); file != end; file++) {
                if (strcmp((*file)->filename, filename) == 0) return *file;
        }
        return nullptr;
}

/** Reset all NewGRFData that was used only while processing data */
static void ClearTemporaryNewGRFData(GRFFile *gf)
{
        /* Clear the GOTO labels used for GRF processing */
        for (GRFLabel *l = gf->label; l != nullptr;) {
                GRFLabel *l2 = l->next;
                free(l);
                l = l2;
        }
        gf->label = nullptr;
}

/**
 * Disable a GRF
 * @param message Error message or STR_NULL.
 * @param config GRFConfig to disable, nullptr for current.
 * @return Error message of the GRF for further customisation.
 */
static GRFError *DisableGrf(StringID message = STR_NULL, GRFConfig *config = nullptr)
{
        GRFFile *file;
        if (config != nullptr) {
                file = GetFileByGRFID(config->ident.grfid);
        } else {
                config = _cur.grfconfig;
                file = _cur.grffile;
        }

        config->status = GCS_DISABLED;
        if (file != nullptr) ClearTemporaryNewGRFData(file);
        if (config == _cur.grfconfig) _cur.skip_sprites = -1;

        if (message != STR_NULL) {
                delete config->error;
                config->error = new GRFError(STR_NEWGRF_ERROR_MSG_FATAL, message);
                if (config == _cur.grfconfig) config->error->param_value[0] = _cur.nfo_line;
        }

        return config->error;
}

/**
 * Information for mapping static StringIDs.
 */
struct StringIDMapping {
        uint32 grfid;     ///< Source NewGRF.
        StringID source;  ///< Source StringID (GRF local).
        StringID *target; ///< Destination for mapping result.
};
typedef SmallVector<StringIDMapping, 16> StringIDMappingVector;
static StringIDMappingVector _string_to_grf_mapping;

/**
 * Record a static StringID for getting translated later.
 * @param source Source StringID (GRF local).
 * @param target Destination for the mapping result.
 */
static void AddStringForMapping(StringID source, StringID *target)
{
        *target = STR_UNDEFINED;
        StringIDMapping *item = _string_to_grf_mapping.Append();
        item->grfid = _cur.grffile->grfid;
        item->source = source;
        item->target = target;
}

/**
 * Perform a mapping from TTDPatch's string IDs to OpenTTD's
 * string IDs, but only for the ones we are aware off; the rest
 * like likely unused and will show a warning.
 * @param str the string ID to convert
 * @return the converted string ID
 */
static StringID TTDPStringIDToOTTDStringIDMapping(StringID str)
{
        /* StringID table for TextIDs 0x4E->0x6D */
        static const StringID units_volume[] = {
                STR_ITEMS,      STR_PASSENGERS, STR_TONS,       STR_BAGS,
                STR_LITERS,     STR_ITEMS,      STR_CRATES,     STR_TONS,
                STR_TONS,       STR_TONS,       STR_TONS,       STR_BAGS,
                STR_TONS,       STR_TONS,       STR_TONS,       STR_BAGS,
                STR_TONS,       STR_TONS,       STR_BAGS,       STR_LITERS,
                STR_TONS,       STR_LITERS,     STR_TONS,       STR_ITEMS,
                STR_BAGS,       STR_LITERS,     STR_TONS,       STR_ITEMS,
                STR_TONS,       STR_ITEMS,      STR_LITERS,     STR_ITEMS
        };

        /* A string straight from a NewGRF; this was already translated by MapGRFStringID(). */
        assert(!IsInsideMM(str, 0xD000, 0xD7FF));

#define TEXTID_TO_STRINGID(begin, end, stringid, stringend) \
        assert_compile(stringend - stringid == end - begin); \
        if (str >= begin && str <= end) return str + (stringid - begin)

        /* We have some changes in our cargo strings, resulting in some missing. */
        TEXTID_TO_STRINGID(0x000E, 0x002D, STR_CARGO_PLURAL_NOTHING,                      STR_CARGO_PLURAL_FIZZY_DRINKS);
        TEXTID_TO_STRINGID(0x002E, 0x004D, STR_CARGO_SINGULAR_NOTHING,                    STR_CARGO_SINGULAR_FIZZY_DRINK);
        if (str >= 0x004E && str <= 0x006D) return units_volume[str - 0x004E];
        TEXTID_TO_STRINGID(0x006E, 0x008D, STR_QUANTITY_NOTHING,                          STR_QUANTITY_FIZZY_DRINKS);
        TEXTID_TO_STRINGID(0x008E, 0x00AD, STR_ABBREV_NOTHING,                            STR_ABBREV_FIZZY_DRINKS);
        TEXTID_TO_STRINGID(0x00D1, 0x00E0, STR_COLOUR_DARK_BLUE,                          STR_COLOUR_WHITE);

        /* Map building names according to our lang file changes. There are several
         * ranges of house ids, all of which need to be remapped to allow newgrfs
         * to use original house names. */
        TEXTID_TO_STRINGID(0x200F, 0x201F, STR_TOWN_BUILDING_NAME_TALL_OFFICE_BLOCK_1,    STR_TOWN_BUILDING_NAME_OLD_HOUSES_1);
        TEXTID_TO_STRINGID(0x2036, 0x2041, STR_TOWN_BUILDING_NAME_COTTAGES_1,             STR_TOWN_BUILDING_NAME_SHOPPING_MALL_1);
        TEXTID_TO_STRINGID(0x2059, 0x205C, STR_TOWN_BUILDING_NAME_IGLOO_1,                STR_TOWN_BUILDING_NAME_PIGGY_BANK_1);

        /* Same thing for industries */
        TEXTID_TO_STRINGID(0x4802, 0x4826, STR_INDUSTRY_NAME_COAL_MINE,                   STR_INDUSTRY_NAME_SUGAR_MINE);
        TEXTID_TO_STRINGID(0x482D, 0x482E, STR_NEWS_INDUSTRY_CONSTRUCTION,                STR_NEWS_INDUSTRY_PLANTED);
        TEXTID_TO_STRINGID(0x4832, 0x4834, STR_NEWS_INDUSTRY_CLOSURE_GENERAL,             STR_NEWS_INDUSTRY_CLOSURE_LACK_OF_TREES);
        TEXTID_TO_STRINGID(0x4835, 0x4838, STR_NEWS_INDUSTRY_PRODUCTION_INCREASE_GENERAL, STR_NEWS_INDUSTRY_PRODUCTION_INCREASE_FARM);
        TEXTID_TO_STRINGID(0x4839, 0x483A, STR_NEWS_INDUSTRY_PRODUCTION_DECREASE_GENERAL, STR_NEWS_INDUSTRY_PRODUCTION_DECREASE_FARM);

        switch (str) {
                case 0x4830: return STR_ERROR_CAN_T_CONSTRUCT_THIS_INDUSTRY;
                case 0x4831: return STR_ERROR_FOREST_CAN_ONLY_BE_PLANTED;
                case 0x483B: return STR_ERROR_CAN_ONLY_BE_POSITIONED;
        }
#undef TEXTID_TO_STRINGID

        if (str == STR_NULL) return STR_EMPTY;

        DEBUG(grf, 0, "Unknown StringID 0x%04X remapped to STR_EMPTY. Please open a Feature Request if you need it", str);

        return STR_EMPTY;
}

/**
 * Used when setting an object's property to map to the GRF's strings
 * while taking in consideration the "drift" between TTDPatch string system and OpenTTD's one
 * @param grfid Id of the grf file.
 * @param str StringID that we want to have the equivalent in OoenTTD.
 * @return The properly adjusted StringID.
 */
StringID MapGRFStringID(uint32 grfid, StringID str)
{
        if (IsInsideMM(str, 0xD800, 0xE000)) {
                /* General text provided by NewGRF.
                 * In the specs this is called the 0xDCxx range (misc presistent texts),
                 * but we meanwhile extended the range to 0xD800-0xDFFF.
                 * Note: We are not involved in the "persistent" business, since we do not store
                 * any NewGRF strings in savegames. */
                return GetGRFStringID(grfid, str);
        } else if (IsInsideMM(str, 0xD000, 0xD800)) {
                /* Callback text provided by NewGRF.
                 * In the specs this is called the 0xD0xx range (misc graphics texts).
                 * These texts can be returned by various callbacks.
                 *
                 * Due to how TTDP implements the GRF-local- to global-textid translation
                 * texts included via 0x80 or 0x81 control codes have to add 0x400 to the textid.
                 * We do not care about that difference and just mask out the 0x400 bit.
                 */
                str &= ~0x400;
                return GetGRFStringID(grfid, str);
        } else {
                /* The NewGRF wants to include/reference an original TTD string.
                 * Try our best to find an equivalent one. */
                return TTDPStringIDToOTTDStringIDMapping(str);
        }
}

static std::map<uint32, uint32> _grf_id_overrides;

/**
 * Set the override for a NewGRF
 * @param source_grfid The grfID which wants to override another NewGRF.
 * @param target_grfid The grfID which is being overridden.
 */
static void SetNewGRFOverride(uint32 source_grfid, uint32 target_grfid)
{
        _grf_id_overrides[source_grfid] = target_grfid;
        grfmsg(5, "SetNewGRFOverride: Added override of 0x%X to 0x%X", BSWAP32(source_grfid), BSWAP32(target_grfid));
}

/**
 * Returns the engine associated to a certain internal_id, resp. allocates it.
 * @param file NewGRF that wants to change the engine.
 * @param type Vehicle type.
 * @param internal_id Engine ID inside the NewGRF.
 * @param static_access If the engine is not present, return nullptr instead of allocating a new engine. (Used for static Action 0x04).
 * @return The requested engine.
 */
static Engine *GetNewEngine(const GRFFile *file, VehicleType type, uint16 internal_id, bool static_access = false)
{
        /* Hack for add-on GRFs that need to modify another GRF's engines. This lets
         * them use the same engine slots. */
        uint32 scope_grfid = INVALID_GRFID; // If not using dynamic_engines, all newgrfs share their ID range
        if (_settings_game.vehicle.dynamic_engines) {
                /* If dynamic_engies is enabled, there can be multiple independent ID ranges. */
                scope_grfid = file->grfid;
                uint32 override = _grf_id_overrides[file->grfid];
                if (override != 0) {
                        scope_grfid = override;
                        const GRFFile *grf_match = GetFileByGRFID(override);
                        if (grf_match == nullptr) {
                                grfmsg(5, "Tried mapping from GRFID %x to %x but target is not loaded", BSWAP32(file->grfid), BSWAP32(override));
                        } else {
                                grfmsg(5, "Mapping from GRFID %x to %x", BSWAP32(file->grfid), BSWAP32(override));
                        }
                }

                /* Check if the engine is registered in the override manager */
                EngineID engine = _engine_mngr.GetID(type, internal_id, scope_grfid);
                if (engine != INVALID_ENGINE) {
                        Engine *e = Engine::Get(engine);
                        if (e->grf_prop.grffile == nullptr) e->grf_prop.grffile = file;
                        return e;
                }
        }

        /* Check if there is an unreserved slot */
        EngineID engine = _engine_mngr.GetID(type, internal_id, INVALID_GRFID);
        if (engine != INVALID_ENGINE) {
                Engine *e = Engine::Get(engine);

                if (e->grf_prop.grffile == nullptr) {
                        e->grf_prop.grffile = file;
                        grfmsg(5, "Replaced engine at index %d for GRFID %x, type %d, index %d", e->index, BSWAP32(file->grfid), type, internal_id);
                }

                /* Reserve the engine slot */
                if (!static_access) {
                        EngineIDMapping *eid = _engine_mngr.Get(engine);
                        eid->grfid           = scope_grfid; // Note: this is INVALID_GRFID if dynamic_engines is disabled, so no reservation
                }

                return e;
        }

        if (static_access) return nullptr;

        if (!Engine::CanAllocateItem()) {
                grfmsg(0, "Can't allocate any more engines");
                return nullptr;
        }

        size_t engine_pool_size = Engine::GetPoolSize();

        /* ... it's not, so create a new one based off an existing engine */
        Engine *e = new Engine(type, internal_id);
        e->grf_prop.grffile = file;

        /* Reserve the engine slot */
        assert(_engine_mngr.Length() == e->index);
        EngineIDMapping *eid = _engine_mngr.Append();
        eid->type            = type;
        eid->grfid           = scope_grfid; // Note: this is INVALID_GRFID if dynamic_engines is disabled, so no reservation
        eid->internal_id     = internal_id;
        eid->substitute_id   = min(internal_id, _engine_counts[type]); // substitute_id == _engine_counts[subtype] means "no substitute"

        if (engine_pool_size != Engine::GetPoolSize()) {
                /* Resize temporary engine data ... */
                _gted = ReallocT(_gted, Engine::GetPoolSize());

                /* and blank the new block. */
                size_t len = (Engine::GetPoolSize() - engine_pool_size) * sizeof(*_gted);
                memset(_gted + engine_pool_size, 0, len);
        }
        switch (type) {
                case VEH_TRAIN:
                        _gted[e->index].railtypelabel = GetRailTypeInfo(e->u.rail.railtype)->label;
                        break;
                case VEH_ROAD:
                        _gted[e->index].roadsubtype = 0xFF;
                        break;
                default:
                        break;
        }

        grfmsg(5, "Created new engine at index %d for GRFID %x, type %d, index %d", e->index, BSWAP32(file->grfid), type, internal_id);

        return e;
}

/**
 * Return the ID of a new engine
 * @param file The NewGRF file providing the engine.
 * @param type The Vehicle type.
 * @param internal_id NewGRF-internal ID of the engine.
 * @return The new EngineID.
 * @note depending on the dynamic_engine setting and a possible override
 *       property the grfID may be unique or overwriting or partially re-defining
 *       properties of an existing engine.
 */
EngineID GetNewEngineID(const GRFFile *file, VehicleType type, uint16 internal_id)
{
        uint32 scope_grfid = INVALID_GRFID; // If not using dynamic_engines, all newgrfs share their ID range
        if (_settings_game.vehicle.dynamic_engines) {
                scope_grfid = file->grfid;
                uint32 override = _grf_id_overrides[file->grfid];
                if (override != 0) scope_grfid = override;
        }

        return _engine_mngr.GetID(type, internal_id, scope_grfid);
}

/**
 * Map the colour modifiers of TTDPatch to those that Open is using.
 * @param grf_sprite Pointer to the structure been modified.
 */
static void MapSpriteMappingRecolour(PalSpriteID *grf_sprite)
{
        if (HasBit(grf_sprite->pal, 14)) {
                ClrBit(grf_sprite->pal, 14);
                SetBit(grf_sprite->sprite, SPRITE_MODIFIER_OPAQUE);
        }

        if (HasBit(grf_sprite->sprite, 14)) {
                ClrBit(grf_sprite->sprite, 14);
                SetBit(grf_sprite->sprite, PALETTE_MODIFIER_TRANSPARENT);
        }

        if (HasBit(grf_sprite->sprite, 15)) {
                ClrBit(grf_sprite->sprite, 15);
                SetBit(grf_sprite->sprite, PALETTE_MODIFIER_COLOUR);
        }
}

/**
 * Read a sprite and a palette from the GRF and convert them into a format
 * suitable to OpenTTD.
 * @param buf                 Input stream.
 * @param read_flags          Whether to read TileLayoutFlags.
 * @param invert_action1_flag Set to true, if palette bit 15 means 'not from action 1'.
 * @param use_cur_spritesets  Whether to use currently referenceable action 1 sets.
 * @param feature             GrfSpecFeature to use spritesets from.
 * @param [out] grf_sprite    Read sprite and palette.
 * @param [out] max_sprite_offset  Optionally returns the number of sprites in the spriteset of the sprite. (0 if no spritset)
 * @param [out] max_palette_offset Optionally returns the number of sprites in the spriteset of the palette. (0 if no spritset)
 * @return Read TileLayoutFlags.
 */
static TileLayoutFlags ReadSpriteLayoutSprite(ByteReader *buf, bool read_flags, bool invert_action1_flag, bool use_cur_spritesets, int feature, PalSpriteID *grf_sprite, uint16 *max_sprite_offset = nullptr, uint16 *max_palette_offset = nullptr)
{
        grf_sprite->sprite = buf->ReadWord();
        grf_sprite->pal = buf->ReadWord();
        TileLayoutFlags flags = read_flags ? (TileLayoutFlags)buf->ReadWord() : TLF_NOTHING;

        MapSpriteMappingRecolour(grf_sprite);

        bool custom_sprite = HasBit(grf_sprite->pal, 15) != invert_action1_flag;
        ClrBit(grf_sprite->pal, 15);
        if (custom_sprite) {
                /* Use sprite from Action 1 */
                uint index = GB(grf_sprite->sprite, 0, 14);
                if (use_cur_spritesets && (!_cur.IsValidSpriteSet(feature, index) || _cur.GetNumEnts(feature, index) == 0)) {
                        grfmsg(1, "ReadSpriteLayoutSprite: Spritelayout uses undefined custom spriteset %d", index);
                        grf_sprite->sprite = SPR_IMG_QUERY;
                        grf_sprite->pal = PAL_NONE;
                } else {
                        SpriteID sprite = use_cur_spritesets ? _cur.GetSprite(feature, index) : index;
                        if (max_sprite_offset != nullptr) *max_sprite_offset = use_cur_spritesets ? _cur.GetNumEnts(feature, index) : UINT16_MAX;
                        SB(grf_sprite->sprite, 0, SPRITE_WIDTH, sprite);
                        SetBit(grf_sprite->sprite, SPRITE_MODIFIER_CUSTOM_SPRITE);
                }
        } else if ((flags & TLF_SPRITE_VAR10) && !(flags & TLF_SPRITE_REG_FLAGS)) {
                grfmsg(1, "ReadSpriteLayoutSprite: Spritelayout specifies var10 value for non-action-1 sprite");
                DisableGrf(STR_NEWGRF_ERROR_INVALID_SPRITE_LAYOUT);
                return flags;
        }

        if (flags & TLF_CUSTOM_PALETTE) {
                /* Use palette from Action 1 */
                uint index = GB(grf_sprite->pal, 0, 14);
                if (use_cur_spritesets && (!_cur.IsValidSpriteSet(feature, index) || _cur.GetNumEnts(feature, index) == 0)) {
                        grfmsg(1, "ReadSpriteLayoutSprite: Spritelayout uses undefined custom spriteset %d for 'palette'", index);
                        grf_sprite->pal = PAL_NONE;
                } else {
                        SpriteID sprite = use_cur_spritesets ? _cur.GetSprite(feature, index) : index;
                        if (max_palette_offset != nullptr) *max_palette_offset = use_cur_spritesets ? _cur.GetNumEnts(feature, index) : UINT16_MAX;
                        SB(grf_sprite->pal, 0, SPRITE_WIDTH, sprite);
                        SetBit(grf_sprite->pal, SPRITE_MODIFIER_CUSTOM_SPRITE);
                }
        } else if ((flags & TLF_PALETTE_VAR10) && !(flags & TLF_PALETTE_REG_FLAGS)) {
                grfmsg(1, "ReadSpriteLayoutRegisters: Spritelayout specifies var10 value for non-action-1 palette");
                DisableGrf(STR_NEWGRF_ERROR_INVALID_SPRITE_LAYOUT);
                return flags;
        }

        return flags;
}

/**
 * Preprocess the TileLayoutFlags and read register modifiers from the GRF.
 * @param buf        Input stream.
 * @param flags      TileLayoutFlags to process.
 * @param is_parent  Whether the sprite is a parentsprite with a bounding box.
 * @param dts        Sprite layout to insert data into.
 * @param index      Sprite index to process; 0 for ground sprite.
 */
static void ReadSpriteLayoutRegisters(ByteReader *buf, TileLayoutFlags flags, bool is_parent, NewGRFSpriteLayout *dts, uint index)
{
        if (!(flags & TLF_DRAWING_FLAGS)) return;

        if (dts->registers == nullptr) dts->AllocateRegisters();
        TileLayoutRegisters &regs = const_cast<TileLayoutRegisters&>(dts->registers[index]);
        regs.flags = flags & TLF_DRAWING_FLAGS;

        if (flags & TLF_DODRAW)  regs.dodraw  = buf->ReadByte();
        if (flags & TLF_SPRITE)  regs.sprite  = buf->ReadByte();
        if (flags & TLF_PALETTE) regs.palette = buf->ReadByte();

        if (is_parent) {
                if (flags & TLF_BB_XY_OFFSET) {
                        regs.delta.parent[0] = buf->ReadByte();
                        regs.delta.parent[1] = buf->ReadByte();
                }
                if (flags & TLF_BB_Z_OFFSET)    regs.delta.parent[2] = buf->ReadByte();
        } else {
                if (flags & TLF_CHILD_X_OFFSET) regs.delta.child[0]  = buf->ReadByte();
                if (flags & TLF_CHILD_Y_OFFSET) regs.delta.child[1]  = buf->ReadByte();
        }

        if (flags & TLF_SPRITE_VAR10) {
                regs.sprite_var10 = buf->ReadByte();
                if (regs.sprite_var10 > TLR_MAX_VAR10) {
                        grfmsg(1, "ReadSpriteLayoutRegisters: Spritelayout specifies var10 (%d) exceeding the maximal allowed value %d", regs.sprite_var10, TLR_MAX_VAR10);
                        DisableGrf(STR_NEWGRF_ERROR_INVALID_SPRITE_LAYOUT);
                        return;
                }
        }

        if (flags & TLF_PALETTE_VAR10) {
                regs.palette_var10 = buf->ReadByte();
                if (regs.palette_var10 > TLR_MAX_VAR10) {
                        grfmsg(1, "ReadSpriteLayoutRegisters: Spritelayout specifies var10 (%d) exceeding the maximal allowed value %d", regs.palette_var10, TLR_MAX_VAR10);
                        DisableGrf(STR_NEWGRF_ERROR_INVALID_SPRITE_LAYOUT);
                        return;
                }
        }
}

/**
 * Read a spritelayout from the GRF.
 * @param buf                  Input
 * @param num_building_sprites Number of building sprites to read
 * @param use_cur_spritesets   Whether to use currently referenceable action 1 sets.
 * @param feature              GrfSpecFeature to use spritesets from.
 * @param allow_var10          Whether the spritelayout may specifiy var10 values for resolving multiple action-1-2-3 chains
 * @param no_z_position        Whether bounding boxes have no Z offset
 * @param dts                  Layout container to output into
 * @return True on error (GRF was disabled).
 */
static bool ReadSpriteLayout(ByteReader *buf, uint num_building_sprites, bool use_cur_spritesets, byte feature, bool allow_var10, bool no_z_position, NewGRFSpriteLayout *dts)
{
        bool has_flags = HasBit(num_building_sprites, 6);
        ClrBit(num_building_sprites, 6);
        TileLayoutFlags valid_flags = TLF_KNOWN_FLAGS;
        if (!allow_var10) valid_flags &= ~TLF_VAR10_FLAGS;
        dts->Allocate(num_building_sprites); // allocate before reading groundsprite flags

        uint16 *max_sprite_offset = AllocaM(uint16, num_building_sprites + 1);
        uint16 *max_palette_offset = AllocaM(uint16, num_building_sprites + 1);
        MemSetT(max_sprite_offset, 0, num_building_sprites + 1);
        MemSetT(max_palette_offset, 0, num_building_sprites + 1);

        /* Groundsprite */
        TileLayoutFlags flags = ReadSpriteLayoutSprite(buf, has_flags, false, use_cur_spritesets, feature, &dts->ground, max_sprite_offset, max_palette_offset);
        if (_cur.skip_sprites < 0) return true;

        if (flags & ~(valid_flags & ~TLF_NON_GROUND_FLAGS)) {
                grfmsg(1, "ReadSpriteLayout: Spritelayout uses invalid flag 0x%x for ground sprite", flags & ~(valid_flags & ~TLF_NON_GROUND_FLAGS));
                DisableGrf(STR_NEWGRF_ERROR_INVALID_SPRITE_LAYOUT);
                return true;
        }

        ReadSpriteLayoutRegisters(buf, flags, false, dts, 0);
        if (_cur.skip_sprites < 0) return true;

        for (uint i = 0; i < num_building_sprites; i++) {
                DrawTileSeqStruct *seq = const_cast<DrawTileSeqStruct*>(&dts->seq[i]);

                flags = ReadSpriteLayoutSprite(buf, has_flags, false, use_cur_spritesets, feature, &seq->image, max_sprite_offset + i + 1, max_palette_offset + i + 1);
                if (_cur.skip_sprites < 0) return true;

                if (flags & ~valid_flags) {
                        grfmsg(1, "ReadSpriteLayout: Spritelayout uses unknown flag 0x%x", flags & ~valid_flags);
                        DisableGrf(STR_NEWGRF_ERROR_INVALID_SPRITE_LAYOUT);
                        return true;
                }

                seq->delta_x = buf->ReadByte();
                seq->delta_y = buf->ReadByte();

                if (!no_z_position) seq->delta_z = buf->ReadByte();

                if (seq->IsParentSprite()) {
                        seq->size_x = buf->ReadByte();
                        seq->size_y = buf->ReadByte();
                        seq->size_z = buf->ReadByte();
                }

                ReadSpriteLayoutRegisters(buf, flags, seq->IsParentSprite(), dts, i + 1);
                if (_cur.skip_sprites < 0) return true;
        }

        /* Check if the number of sprites per spriteset is consistent */
        bool is_consistent = true;
        dts->consistent_max_offset = 0;
        for (uint i = 0; i < num_building_sprites + 1; i++) {
                if (max_sprite_offset[i] > 0) {
                        if (dts->consistent_max_offset == 0) {
                                dts->consistent_max_offset = max_sprite_offset[i];
                        } else if (dts->consistent_max_offset != max_sprite_offset[i]) {
                                is_consistent = false;
                                break;
                        }
                }
                if (max_palette_offset[i] > 0) {
                        if (dts->consistent_max_offset == 0) {
                                dts->consistent_max_offset = max_palette_offset[i];
                        } else if (dts->consistent_max_offset != max_palette_offset[i]) {
                                is_consistent = false;
                                break;
                        }
                }
        }

        /* When the Action1 sets are unknown, everything should be 0 (no spriteset usage) or UINT16_MAX (some spriteset usage) */
        assert(use_cur_spritesets || (is_consistent && (dts->consistent_max_offset == 0 || dts->consistent_max_offset == UINT16_MAX)));

        if (!is_consistent || dts->registers != nullptr) {
                dts->consistent_max_offset = 0;
                if (dts->registers == nullptr) dts->AllocateRegisters();

                for (uint i = 0; i < num_building_sprites + 1; i++) {
                        TileLayoutRegisters &regs = const_cast<TileLayoutRegisters&>(dts->registers[i]);
                        regs.max_sprite_offset = max_sprite_offset[i];
                        regs.max_palette_offset = max_palette_offset[i];
                }
        }

        return false;
}

/**
 * Translate the refit mask.
 */
static uint32 TranslateRefitMask(uint32 refit_mask)
{
        uint32 result = 0;
        uint8 bit;
        FOR_EACH_SET_BIT(bit, refit_mask) {
                CargoID cargo = GetCargoTranslation(bit, _cur.grffile, true);
                if (cargo != CT_INVALID) SetBit(result, cargo);
        }
        return result;
}

/**
 * Converts TTD(P) Base Price pointers into the enum used by OTTD
 * See http://wiki.ttdpatch.net/tiki-index.php?page=BaseCosts
 * @param base_pointer TTD(P) Base Price Pointer
 * @param error_location Function name for grf error messages
 * @param[out] index If \a base_pointer is valid, \a index is assigned to the matching price; else it is left unchanged
 */
static void ConvertTTDBasePrice(uint32 base_pointer, const char *error_location, Price *index)
{
        /* Special value for 'none' */
        if (base_pointer == 0) {
                *index = INVALID_PRICE;
                return;
        }

        static const uint32 start = 0x4B34; ///< Position of first base price
        static const uint32 size  = 6;      ///< Size of each base price record

        if (base_pointer < start || (base_pointer - start) % size != 0 || (base_pointer - start) / size >= PR_END) {
                grfmsg(1, "%s: Unsupported running cost base 0x%04X, ignoring", error_location, base_pointer);
                return;
        }

        *index = (Price)((base_pointer - start) / size);
}

/** Possible return values for the FeatureChangeInfo functions */
enum ChangeInfoResult {
        CIR_SUCCESS,    ///< Variable was parsed and read
        CIR_DISABLED,   ///< GRF was disabled due to error
        CIR_UNHANDLED,  ///< Variable was parsed but unread
        CIR_UNKNOWN,    ///< Variable is unknown
        CIR_INVALID_ID, ///< Attempt to modify an invalid ID
};

typedef ChangeInfoResult (*VCI_Handler)(uint engine, int numinfo, int prop, ByteReader *buf);

/**
 * Define properties common to all vehicles
 * @param ei Engine info.
 * @param prop The property to change.
 * @param buf The property value.
 * @return ChangeInfoResult.
 */
static ChangeInfoResult CommonVehicleChangeInfo(EngineInfo *ei, int prop, ByteReader *buf)
{
        switch (prop) {
                case 0x00: // Introduction date
                        ei->base_intro = buf->ReadWord() + DAYS_TILL_ORIGINAL_BASE_YEAR;
                        break;

                case 0x02: // Decay speed
                        ei->decay_speed = buf->ReadByte();
                        break;

                case 0x03: // Vehicle life
                        ei->lifelength = buf->ReadByte();
                        break;

                case 0x04: // Model life
                        ei->base_life = buf->ReadByte();
                        break;

                case 0x06: // Climates available
                        ei->climates = buf->ReadByte();
                        break;

                case PROP_VEHICLE_LOAD_AMOUNT: // 0x07 Loading speed
                        /* Amount of cargo loaded during a vehicle's "loading tick" */
                        ei->load_amount = buf->ReadByte();
                        break;

                default:
                        return CIR_UNKNOWN;
        }

        return CIR_SUCCESS;
}

/**
 * Define properties for rail vehicles
 * @param engine :ocal ID of the first vehicle.
 * @param numinfo Number of subsequent IDs to change the property for.
 * @param prop The property to change.
 * @param buf The property value.
 * @return ChangeInfoResult.
 */
static ChangeInfoResult RailVehicleChangeInfo(uint engine, int numinfo, int prop, ByteReader *buf)
{
        ChangeInfoResult ret = CIR_SUCCESS;

        for (int i = 0; i < numinfo; i++) {
                Engine *e = GetNewEngine(_cur.grffile, VEH_TRAIN, engine + i);
                if (e == nullptr) return CIR_INVALID_ID; // No engine could be allocated, so neither can any next vehicles

                EngineInfo *ei = &e->info;
                RailVehicleInfo *rvi = &e->u.rail;

                switch (prop) {
                        case 0x05: { // Track type
                                uint8 tracktype = buf->ReadByte();

                                if (tracktype < _cur.grffile->railtype_list.Length()) {
                                        _gted[e->index].railtypelabel = _cur.grffile->railtype_list[tracktype];
                                        break;
                                }

                                switch (tracktype) {
                                        case 0: _gted[e->index].railtypelabel = rvi->engclass >= 2 ? RAILTYPE_ELECTRIC_LABEL : RAILTYPE_RAIL_LABEL; break;
                                        case 1: _gted[e->index].railtypelabel = RAILTYPE_MONO_LABEL; break;
                                        case 2: _gted[e->index].railtypelabel = RAILTYPE_MAGLEV_LABEL; break;
                                        default:
                                                grfmsg(1, "RailVehicleChangeInfo: Invalid track type %d specified, ignoring", tracktype);
                                                break;
                                }
                                break;
                        }

                        case 0x08: // AI passenger service
                                /* Tells the AI that this engine is designed for
                                 * passenger services and shouldn't be used for freight. */
                                rvi->ai_passenger_only = buf->ReadByte();
                                break;

                        case PROP_TRAIN_SPEED: { // 0x09 Speed (1 unit is 1 km-ish/h)
                                uint16 speed = buf->ReadWord();
                                if (speed == 0xFFFF) speed = 0;

                                rvi->max_speed = speed;
                                break;
                        }

                        case PROP_TRAIN_POWER: // 0x0B Power
                                rvi->power = buf->ReadWord();

                                /* Set engine / wagon state based on power */
                                if (rvi->power != 0) {
                                        if (rvi->railveh_type == RAILVEH_WAGON) {
                                                rvi->railveh_type = RAILVEH_SINGLEHEAD;
                                        }
                                } else {
                                        rvi->railveh_type = RAILVEH_WAGON;
                                }
                                break;

                        case PROP_TRAIN_RUNNING_COST_FACTOR: // 0x0D Running cost factor
                                rvi->running_cost = buf->ReadByte();
                                break;

                        case 0x0E: // Running cost base
                                ConvertTTDBasePrice(buf->ReadDWord(), "RailVehicleChangeInfo", &rvi->running_cost_class);
                                break;

                        case 0x12: { // Sprite ID
                                uint8 spriteid = buf->ReadByte();
                                uint8 orig_spriteid = spriteid;

                                /* TTD sprite IDs point to a location in a 16bit array, but we use it
                                 * as an array index, so we need it to be half the original value. */
                                if (spriteid < 0xFD) spriteid >>= 1;

                                if (IsValidNewGRFImageIndex<VEH_TRAIN>(spriteid)) {
                                        rvi->image_index = spriteid;
                                } else {
                                        grfmsg(1, "RailVehicleChangeInfo: Invalid Sprite %d specified, ignoring", orig_spriteid);
                                        rvi->image_index = 0;
                                }
                                break;
                        }

                        case 0x13: { // Dual-headed
                                uint8 dual = buf->ReadByte();

                                if (dual != 0) {
                                        rvi->railveh_type = RAILVEH_MULTIHEAD;
                                } else {
                                        rvi->railveh_type = rvi->power == 0 ?
                                                RAILVEH_WAGON : RAILVEH_SINGLEHEAD;
                                }
                                break;
                        }

                        case PROP_TRAIN_CARGO_CAPACITY: // 0x14 Cargo capacity
                                rvi->capacity = buf->ReadByte();
                                break;

                        case 0x15: { // Cargo type
                                _gted[e->index].defaultcargo_grf = _cur.grffile;
                                uint8 ctype = buf->ReadByte();

                                if (ctype == 0xFF) {
                                        /* 0xFF is specified as 'use first refittable' */
                                        ei->cargo_type = CT_INVALID;
                                } else if (_cur.grffile->grf_version >= 8) {
                                        /* Use translated cargo. Might result in CT_INVALID (first refittable), if cargo is not defined. */
                                        ei->cargo_type = GetCargoTranslation(ctype, _cur.grffile);
                                } else if (ctype < NUM_CARGO) {
                                        /* Use untranslated cargo. */
                                        ei->cargo_type = ctype;
                                } else {
                                        ei->cargo_type = CT_INVALID;
                                        grfmsg(2, "RailVehicleChangeInfo: Invalid cargo type %d, using first refittable", ctype);
                                }
                                break;
                        }

                        case PROP_TRAIN_WEIGHT: // 0x16 Weight
                                SB(rvi->weight, 0, 8, buf->ReadByte());
                                break;

                        case PROP_TRAIN_COST_FACTOR: // 0x17 Cost factor
                                rvi->cost_factor = buf->ReadByte();
                                break;

                        case 0x18: // AI rank
                                grfmsg(2, "RailVehicleChangeInfo: Property 0x18 'AI rank' not used by NoAI, ignored.");
                                buf->ReadByte();
                                break;

                        case 0x19: { // Engine traction type
                                /* What do the individual numbers mean?
                                 * 0x00 .. 0x07: Steam
                                 * 0x08 .. 0x27: Diesel
                                 * 0x28 .. 0x31: Electric
                                 * 0x32 .. 0x37: Monorail
                                 * 0x38 .. 0x41: Maglev
                                 */
                                uint8 traction = buf->ReadByte();
                                EngineClass engclass;

                                if (traction <= 0x07) {
                                        engclass = EC_STEAM;
                                } else if (traction <= 0x27) {
                                        engclass = EC_DIESEL;
                                } else if (traction <= 0x31) {
                                        engclass = EC_ELECTRIC;
                                } else if (traction <= 0x37) {
                                        engclass = EC_MONORAIL;
                                } else if (traction <= 0x41) {
                                        engclass = EC_MAGLEV;
                                } else {
                                        break;
                                }

                                if (_cur.grffile->railtype_list.Length() == 0) {
                                        /* Use traction type to select between normal and electrified
                                         * rail only when no translation list is in place. */
                                        if (_gted[e->index].railtypelabel == RAILTYPE_RAIL_LABEL     && engclass >= EC_ELECTRIC) _gted[e->index].railtypelabel = RAILTYPE_ELECTRIC_LABEL;
                                        if (_gted[e->index].railtypelabel == RAILTYPE_ELECTRIC_LABEL && engclass  < EC_ELECTRIC) _gted[e->index].railtypelabel = RAILTYPE_RAIL_LABEL;
                                }

                                rvi->engclass = engclass;
                                break;
                        }

                        case 0x1A: // Alter purchase list sort order
                                AlterVehicleListOrder(e->index, buf->ReadExtendedByte());
                                break;

                        case 0x1B: // Powered wagons power bonus
                                rvi->pow_wag_power = buf->ReadWord();
                                break;

                        case 0x1C: // Refit cost
                                ei->refit_cost = buf->ReadByte();
                                break;

                        case 0x1D: { // Refit cargo
                                uint32 mask = buf->ReadDWord();
                                _gted[e->index].UpdateRefittability(mask != 0);
                                ei->refit_mask = TranslateRefitMask(mask);
                                _gted[e->index].defaultcargo_grf = _cur.grffile;
                                break;
                        }

                        case 0x1E: // Callback
                                ei->callback_mask = buf->ReadByte();
                                break;

                        case PROP_TRAIN_TRACTIVE_EFFORT: // 0x1F Tractive effort coefficient
                                rvi->tractive_effort = buf->ReadByte();
                                break;

                        case 0x20: // Air drag
                                rvi->air_drag = buf->ReadByte();
                                break;

                        case PROP_TRAIN_SHORTEN_FACTOR: // 0x21 Shorter vehicle
                                rvi->shorten_factor = buf->ReadByte();
                                break;

                        case 0x22: // Visual effect
                                rvi->visual_effect = buf->ReadByte();
                                /* Avoid accidentally setting visual_effect to the default value
                                 * Since bit 6 (disable effects) is set anyways, we can safely erase some bits. */
                                if (rvi->visual_effect == VE_DEFAULT) {
                                        assert(HasBit(rvi->visual_effect, VE_DISABLE_EFFECT));
                                        SB(rvi->visual_effect, VE_TYPE_START, VE_TYPE_COUNT, 0);
                                }
                                break;

                        case 0x23: // Powered wagons weight bonus
                                rvi->pow_wag_weight = buf->ReadByte();
                                break;

                        case 0x24: { // High byte of vehicle weight
                                byte weight = buf->ReadByte();

                                if (weight > 4) {
                                        grfmsg(2, "RailVehicleChangeInfo: Nonsensical weight of %d tons, ignoring", weight << 8);
                                } else {
                                        SB(rvi->weight, 8, 8, weight);
                                }
                                break;
                        }

                        case PROP_TRAIN_USER_DATA: // 0x25 User-defined bit mask to set when checking veh. var. 42
                                rvi->user_def_data = buf->ReadByte();
                                break;

                        case 0x26: // Retire vehicle early
                                ei->retire_early = buf->ReadByte();
                                break;

                        case 0x27: // Miscellaneous flags
                                ei->misc_flags = buf->ReadByte();
                                _loaded_newgrf_features.has_2CC |= HasBit(ei->misc_flags, EF_USES_2CC);
                                _gted[e->index].prop27_set = true;
                                break;

                        case 0x28: // Cargo classes allowed
                                _gted[e->index].cargo_allowed = buf->ReadWord();
                                _gted[e->index].UpdateRefittability(_gted[e->index].cargo_allowed != 0);
                                _gted[e->index].defaultcargo_grf = _cur.grffile;
                                break;

                        case 0x29: // Cargo classes disallowed
                                _gted[e->index].cargo_disallowed = buf->ReadWord();
                                _gted[e->index].UpdateRefittability(false);
                                break;

                        case 0x2A: // Long format introduction date (days since year 0)
                                ei->base_intro = buf->ReadDWord();
                                break;

                        case PROP_TRAIN_CARGO_AGE_PERIOD: // 0x2B Cargo aging period
                                ei->cargo_age_period = buf->ReadWord();
                                break;

                        case 0x2C:   // CTT refit include list
                        case 0x2D: { // CTT refit exclude list
                                uint8 count = buf->ReadByte();
                                _gted[e->index].UpdateRefittability(prop == 0x2C && count != 0);
                                if (prop == 0x2C) _gted[e->index].defaultcargo_grf = _cur.grffile;
                                uint32 &ctt = prop == 0x2C ? _gted[e->index].ctt_include_mask : _gted[e->index].ctt_exclude_mask;
                                ctt = 0;
                                while (count--) {
                                        CargoID ctype = GetCargoTranslation(buf->ReadByte(), _cur.grffile);
                                        if (ctype == CT_INVALID) continue;
                                        SetBit(ctt, ctype);
                                }
                                break;
                        }

                        default:
                                ret = CommonVehicleChangeInfo(ei, prop, buf);
                                break;
                }
        }

        return ret;
}

/**
 * Define properties for road vehicles
 * @param engine Local ID of the first vehicle.
 * @param numinfo Number of subsequent IDs to change the property for.
 * @param prop The property to change.
 * @param buf The property value.
 * @return ChangeInfoResult.
 */
static ChangeInfoResult RoadVehicleChangeInfo(uint engine, int numinfo, int prop, ByteReader *buf)
{
        ChangeInfoResult ret = CIR_SUCCESS;

        for (int i = 0; i < numinfo; i++) {
                Engine *e = GetNewEngine(_cur.grffile, VEH_ROAD, engine + i);
                if (e == nullptr) return CIR_INVALID_ID; // No engine could be allocated, so neither can any next vehicles

                EngineInfo *ei = &e->info;
                RoadVehicleInfo *rvi = &e->u.road;

                switch (prop) {
                        case 0x05: // Road/tram subtype
                                _gted[e->index].roadsubtype = buf->ReadByte();
                                break;

                        case 0x08: // Speed (1 unit is 0.5 kmh)
                                rvi->max_speed = buf->ReadByte();
                                break;

                        case PROP_ROADVEH_RUNNING_COST_FACTOR: // 0x09 Running cost factor
                                rvi->running_cost = buf->ReadByte();
                                break;

                        case 0x0A: // Running cost base
                                ConvertTTDBasePrice(buf->ReadDWord(), "RoadVehicleChangeInfo", &rvi->running_cost_class);
                                break;

                        case 0x0E: { // Sprite ID
                                uint8 spriteid = buf->ReadByte();
                                uint8 orig_spriteid = spriteid;

                                /* cars have different custom id in the GRF file */
                                if (spriteid == 0xFF) spriteid = 0xFD;

                                if (spriteid < 0xFD) spriteid >>= 1;

                                if (IsValidNewGRFImageIndex<VEH_ROAD>(spriteid)) {
                                        rvi->image_index = spriteid;
                                } else {
                                        grfmsg(1, "RoadVehicleChangeInfo: Invalid Sprite %d specified, ignoring", orig_spriteid);
                                        rvi->image_index = 0;
                                }
                                break;
                        }

                        case PROP_ROADVEH_CARGO_CAPACITY: // 0x0F Cargo capacity
                                rvi->capacity = buf->ReadByte();
                                break;

                        case 0x10: { // Cargo type
                                _gted[e->index].defaultcargo_grf = _cur.grffile;
                                uint8 ctype = buf->ReadByte();

                                if (ctype == 0xFF) {
                                        /* 0xFF is specified as 'use first refittable' */
                                        ei->cargo_type = CT_INVALID;
                                } else if (_cur.grffile->grf_version >= 8) {
                                        /* Use translated cargo. Might result in CT_INVALID (first refittable), if cargo is not defined. */
                                        ei->cargo_type = GetCargoTranslation(ctype, _cur.grffile);
                                } else if (ctype < NUM_CARGO) {
                                        /* Use untranslated cargo. */
                                        ei->cargo_type = ctype;
                                } else {
                                        ei->cargo_type = CT_INVALID;
                                        grfmsg(2, "RailVehicleChangeInfo: Invalid cargo type %d, using first refittable", ctype);
                                }
                                break;
                        }

                        case PROP_ROADVEH_COST_FACTOR: // 0x11 Cost factor
                                rvi->cost_factor = buf->ReadByte();
                                break;

                        case 0x12: // SFX
                                rvi->sfx = GetNewGRFSoundID(_cur.grffile, buf->ReadByte());
                                break;

                        case PROP_ROADVEH_POWER: // Power in units of 10 HP.
                                rvi->power = buf->ReadByte();
                                break;

                        case PROP_ROADVEH_WEIGHT: // Weight in units of 1/4 tons.
                                rvi->weight = buf->ReadByte();
                                break;

                        case PROP_ROADVEH_SPEED: // Speed in mph/0.8
                                _gted[e->index].rv_max_speed = buf->ReadByte();
                                break;

                        case 0x16: { // Cargoes available for refitting
                                uint32 mask = buf->ReadDWord();
                                _gted[e->index].UpdateRefittability(mask != 0);
                                ei->refit_mask = TranslateRefitMask(mask);
                                _gted[e->index].defaultcargo_grf = _cur.grffile;
                                break;
                        }

                        case 0x17: // Callback mask
                                ei->callback_mask = buf->ReadByte();
                                break;

                        case PROP_ROADVEH_TRACTIVE_EFFORT: // Tractive effort coefficient in 1/256.
                                rvi->tractive_effort = buf->ReadByte();
                                break;

                        case 0x19: // Air drag
                                rvi->air_drag = buf->ReadByte();
                                break;

                        case 0x1A: // Refit cost
                                ei->refit_cost = buf->ReadByte();
                                break;

                        case 0x1B: // Retire vehicle early
                                ei->retire_early = buf->ReadByte();
                                break;

                        case 0x1C: // Miscellaneous flags
                                ei->misc_flags = buf->ReadByte();
                                _loaded_newgrf_features.has_2CC |= HasBit(ei->misc_flags, EF_USES_2CC);
                                break;

                        case 0x1D: // Cargo classes allowed
                                _gted[e->index].cargo_allowed = buf->ReadWord();
                                _gted[e->index].UpdateRefittability(_gted[e->index].cargo_allowed != 0);
                                _gted[e->index].defaultcargo_grf = _cur.grffile;
                                break;

                        case 0x1E: // Cargo classes disallowed
                                _gted[e->index].cargo_disallowed = buf->ReadWord();
                                _gted[e->index].UpdateRefittability(false);
                                break;

                        case 0x1F: // Long format introduction date (days since year 0)
                                ei->base_intro = buf->ReadDWord();
                                break;

                        case 0x20: // Alter purchase list sort order
                                AlterVehicleListOrder(e->index, buf->ReadExtendedByte());
                                break;

                        case 0x21: // Visual effect
                                rvi->visual_effect = buf->ReadByte();
                                /* Avoid accidentally setting visual_effect to the default value
                                 * Since bit 6 (disable effects) is set anyways, we can safely erase some bits. */
                                if (rvi->visual_effect == VE_DEFAULT) {
                                        assert(HasBit(rvi->visual_effect, VE_DISABLE_EFFECT));
                                        SB(rvi->visual_effect, VE_TYPE_START, VE_TYPE_COUNT, 0);
                                }
                                break;

                        case PROP_ROADVEH_CARGO_AGE_PERIOD: // 0x22 Cargo aging period
                                ei->cargo_age_period = buf->ReadWord();
                                break;

                        case PROP_ROADVEH_SHORTEN_FACTOR: // 0x23 Shorter vehicle
                                rvi->shorten_factor = buf->ReadByte();
                                break;

                        case 0x24:   // CTT refit include list
                        case 0x25: { // CTT refit exclude list
                                uint8 count = buf->ReadByte();
                                _gted[e->index].UpdateRefittability(prop == 0x24 && count != 0);
                                if (prop == 0x24) _gted[e->index].defaultcargo_grf = _cur.grffile;
                                uint32 &ctt = prop == 0x24 ? _gted[e->index].ctt_include_mask : _gted[e->index].ctt_exclude_mask;
                                ctt = 0;
                                while (count--) {
                                        CargoID ctype = GetCargoTranslation(buf->ReadByte(), _cur.grffile);
                                        if (ctype == CT_INVALID) continue;
                                        SetBit(ctt, ctype);
                                }
                                break;
                        }

                        default:
                                ret = CommonVehicleChangeInfo(ei, prop, buf);
                                break;
                }
        }

        return ret;
}

/**
 * Define properties for ships
 * @param engine Local ID of the first vehicle.
 * @param numinfo Number of subsequent IDs to change the property for.
 * @param prop The property to change.
 * @param buf The property value.
 * @return ChangeInfoResult.
 */
static ChangeInfoResult ShipVehicleChangeInfo(uint engine, int numinfo, int prop, ByteReader *buf)
{
        ChangeInfoResult ret = CIR_SUCCESS;

        for (int i = 0; i < numinfo; i++) {
                Engine *e = GetNewEngine(_cur.grffile, VEH_SHIP, engine + i);
                if (e == nullptr) return CIR_INVALID_ID; // No engine could be allocated, so neither can any next vehicles

                EngineInfo *ei = &e->info;
                ShipVehicleInfo *svi = &e->u.ship;

                switch (prop) {
                        case 0x08: { // Sprite ID
                                uint8 spriteid = buf->ReadByte();
                                uint8 orig_spriteid = spriteid;

                                /* ships have different custom id in the GRF file */
                                if (spriteid == 0xFF) spriteid = 0xFD;

                                if (spriteid < 0xFD) spriteid >>= 1;

                                if (IsValidNewGRFImageIndex<VEH_SHIP>(spriteid)) {
                                        svi->image_index = spriteid;
                                } else {
                                        grfmsg(1, "ShipVehicleChangeInfo: Invalid Sprite %d specified, ignoring", orig_spriteid);
                                        svi->image_index = 0;
                                }
                                break;
                        }

                        case 0x09: // Refittable
                                svi->old_refittable = (buf->ReadByte() != 0);
                                break;

                        case PROP_SHIP_COST_FACTOR: // 0x0A Cost factor
                                svi->cost_factor = buf->ReadByte();
                                break;

                        case PROP_SHIP_SPEED: // 0x0B Speed (1 unit is 0.5 km-ish/h)
                                svi->max_speed = buf->ReadByte();
                                break;

                        case 0x0C: { // Cargo type
                                _gted[e->index].defaultcargo_grf = _cur.grffile;
                                uint8 ctype = buf->ReadByte();

                                if (ctype == 0xFF) {
                                        /* 0xFF is specified as 'use first refittable' */
                                        ei->cargo_type = CT_INVALID;
                                } else if (_cur.grffile->grf_version >= 8) {
                                        /* Use translated cargo. Might result in CT_INVALID (first refittable), if cargo is not defined. */
                                        ei->cargo_type = GetCargoTranslation(ctype, _cur.grffile);
                                } else if (ctype < NUM_CARGO) {
                                        /* Use untranslated cargo. */
                                        ei->cargo_type = ctype;
                                } else {
                                        ei->cargo_type = CT_INVALID;
                                        grfmsg(2, "RailVehicleChangeInfo: Invalid cargo type %d, using first refittable", ctype);
                                }
                                break;
                        }

                        case PROP_SHIP_CARGO_CAPACITY: // 0x0D Cargo capacity
                                svi->capacity = buf->ReadWord();
                                break;

                        case PROP_SHIP_RUNNING_COST_FACTOR: // 0x0F Running cost factor
                                svi->running_cost = buf->ReadByte();
                                break;

                        case 0x10: // SFX
                                svi->sfx = GetNewGRFSoundID(_cur.grffile, buf->ReadByte());
                                break;

                        case 0x11: { // Cargoes available for refitting
                                uint32 mask = buf->ReadDWord();
                                _gted[e->index].UpdateRefittability(mask != 0);
                                ei->refit_mask = TranslateRefitMask(mask);
                                _gted[e->index].defaultcargo_grf = _cur.grffile;
                                break;
                        }

                        case 0x12: // Callback mask
                                ei->callback_mask = buf->ReadByte();
                                break;

                        case 0x13: // Refit cost
                                ei->refit_cost = buf->ReadByte();
                                break;

                        case 0x14: // Ocean speed fraction
                                svi->ocean_speed_frac = buf->ReadByte();
                                break;

                        case 0x15: // Canal speed fraction
                                svi->canal_speed_frac = buf->ReadByte();
                                break;

                        case 0x16: // Retire vehicle early
                                ei->retire_early = buf->ReadByte();
                                break;

                        case 0x17: // Miscellaneous flags
                                ei->misc_flags = buf->ReadByte();
                                _loaded_newgrf_features.has_2CC |= HasBit(ei->misc_flags, EF_USES_2CC);
                                break;

                        case 0x18: // Cargo classes allowed
                                _gted[e->index].cargo_allowed = buf->ReadWord();
                                _gted[e->index].UpdateRefittability(_gted[e->index].cargo_allowed != 0);
                                _gted[e->index].defaultcargo_grf = _cur.grffile;
                                break;

                        case 0x19: // Cargo classes disallowed
                                _gted[e->index].cargo_disallowed = buf->ReadWord();
                                _gted[e->index].UpdateRefittability(false);
                                break;

                        case 0x1A: // Long format introduction date (days since year 0)
                                ei->base_intro = buf->ReadDWord();
                                break;

                        case 0x1B: // Alter purchase list sort order
                                AlterVehicleListOrder(e->index, buf->ReadExtendedByte());
                                break;

                        case 0x1C: // Visual effect
                                svi->visual_effect = buf->ReadByte();
                                /* Avoid accidentally setting visual_effect to the default value
                                 * Since bit 6 (disable effects) is set anyways, we can safely erase some bits. */
                                if (svi->visual_effect == VE_DEFAULT) {
                                        assert(HasBit(svi->visual_effect, VE_DISABLE_EFFECT));
                                        SB(svi->visual_effect, VE_TYPE_START, VE_TYPE_COUNT, 0);
                                }
                                break;

                        case PROP_SHIP_CARGO_AGE_PERIOD: // 0x1D Cargo aging period
                                ei->cargo_age_period = buf->ReadWord();
                                break;

                        case 0x1E:   // CTT refit include list
                        case 0x1F: { // CTT refit exclude list
                                uint8 count = buf->ReadByte();
                                _gted[e->index].UpdateRefittability(prop == 0x1E && count != 0);
                                if (prop == 0x1E) _gted[e->index].defaultcargo_grf = _cur.grffile;
                                uint32 &ctt = prop == 0x1E ? _gted[e->index].ctt_include_mask : _gted[e->index].ctt_exclude_mask;
                                ctt = 0;
                                while (count--) {
                                        CargoID ctype = GetCargoTranslation(buf->ReadByte(), _cur.grffile);
                                        if (ctype == CT_INVALID) continue;
                                        SetBit(ctt, ctype);
                                }
                                break;
                        }

                        default:
                                ret = CommonVehicleChangeInfo(ei, prop, buf);
                                break;
                }
        }

        return ret;
}

/**
 * Define properties for aircraft
 * @param engine Local ID of the aircraft.
 * @param numinfo Number of subsequent IDs to change the property for.
 * @param prop The property to change.
 * @param buf The property value.
 * @return ChangeInfoResult.
 */
static ChangeInfoResult AircraftVehicleChangeInfo(uint engine, int numinfo, int prop, ByteReader *buf)
{
        ChangeInfoResult ret = CIR_SUCCESS;

        for (int i = 0; i < numinfo; i++) {
                Engine *e = GetNewEngine(_cur.grffile, VEH_AIRCRAFT, engine + i);
                if (e == nullptr) return CIR_INVALID_ID; // No engine could be allocated, so neither can any next vehicles

                EngineInfo *ei = &e->info;
                AircraftVehicleInfo *avi = &e->u.air;

                switch (prop) {
                        case 0x08: { // Sprite ID
                                uint8 spriteid = buf->ReadByte();
                                uint8 orig_spriteid = spriteid;

                                /* aircraft have different custom id in the GRF file */
                                if (spriteid == 0xFF) spriteid = 0xFD;

                                if (spriteid < 0xFD) spriteid >>= 1;

                                if (IsValidNewGRFImageIndex<VEH_AIRCRAFT>(spriteid)) {
                                        avi->image_index = spriteid;
                                } else {
                                        grfmsg(1, "AircraftVehicleChangeInfo: Invalid Sprite %d specified, ignoring", orig_spriteid);
                                        avi->image_index = 0;
                                }
                                break;
                        }

                        case 0x09: // Helicopter
                                if (buf->ReadByte() == 0) {
                                        avi->subtype = AIR_HELI;
                                } else {
                                        SB(avi->subtype, 0, 1, 1); // AIR_CTOL
                                }
                                break;

                        case 0x0A: // Large
                                SB(avi->subtype, 1, 1, (buf->ReadByte() != 0 ? 1 : 0)); // AIR_FAST
                                break;

                        case PROP_AIRCRAFT_COST_FACTOR: // 0x0B Cost factor
                                avi->cost_factor = buf->ReadByte();
                                break;

                        case PROP_AIRCRAFT_SPEED: // 0x0C Speed (1 unit is 8 mph, we translate to 1 unit is 1 km-ish/h)
                                avi->max_speed = (buf->ReadByte() * 128) / 10;
                                break;

                        case 0x0D: // Acceleration
                                avi->acceleration = buf->ReadByte();
                                break;

                        case PROP_AIRCRAFT_RUNNING_COST_FACTOR: // 0x0E Running cost factor
                                avi->running_cost = buf->ReadByte();
                                break;

                        case PROP_AIRCRAFT_PASSENGER_CAPACITY: // 0x0F Passenger capacity
                                avi->passenger_capacity = buf->ReadWord();
                                break;

                        case PROP_AIRCRAFT_MAIL_CAPACITY: // 0x11 Mail capacity
                                avi->mail_capacity = buf->ReadByte();
                                break;

                        case 0x12: // SFX
                                avi->sfx = GetNewGRFSoundID(_cur.grffile, buf->ReadByte());
                                break;

                        case 0x13: { // Cargoes available for refitting
                                uint32 mask = buf->ReadDWord();
                                _gted[e->index].UpdateRefittability(mask != 0);
                                ei->refit_mask = TranslateRefitMask(mask);
                                _gted[e->index].defaultcargo_grf = _cur.grffile;
                                break;
                        }

                        case 0x14: // Callback mask
                                ei->callback_mask = buf->ReadByte();
                                break;

                        case 0x15: // Refit cost
                                ei->refit_cost = buf->ReadByte();
                                break;

                        case 0x16: // Retire vehicle early
                                ei->retire_early = buf->ReadByte();
                                break;

                        case 0x17: // Miscellaneous flags
                                ei->misc_flags = buf->ReadByte();
                                _loaded_newgrf_features.has_2CC |= HasBit(ei->misc_flags, EF_USES_2CC);
                                break;

                        case 0x18: // Cargo classes allowed
                                _gted[e->index].cargo_allowed = buf->ReadWord();
                                _gted[e->index].UpdateRefittability(_gted[e->index].cargo_allowed != 0);
                                _gted[e->index].defaultcargo_grf = _cur.grffile;
                                break;

                        case 0x19: // Cargo classes disallowed
                                _gted[e->index].cargo_disallowed = buf->ReadWord();
                                _gted[e->index].UpdateRefittability(false);
                                break;

                        case 0x1A: // Long format introduction date (days since year 0)
                                ei->base_intro = buf->ReadDWord();
                                break;

                        case 0x1B: // Alter purchase list sort order
                                AlterVehicleListOrder(e->index, buf->ReadExtendedByte());
                                break;

                        case PROP_AIRCRAFT_CARGO_AGE_PERIOD: // 0x1C Cargo aging period
                                ei->cargo_age_period = buf->ReadWord();
                                break;

                        case 0x1D:   // CTT refit include list
                        case 0x1E: { // CTT refit exclude list
                                uint8 count = buf->ReadByte();
                                _gted[e->index].UpdateRefittability(prop == 0x1D && count != 0);
                                if (prop == 0x1D) _gted[e->index].defaultcargo_grf = _cur.grffile;
                                uint32 &ctt = prop == 0x1D ? _gted[e->index].ctt_include_mask : _gted[e->index].ctt_exclude_mask;
                                ctt = 0;
                                while (count--) {
                                        CargoID ctype = GetCargoTranslation(buf->ReadByte(), _cur.grffile);
                                        if (ctype == CT_INVALID) continue;
                                        SetBit(ctt, ctype);
                                }
                                break;
                        }

                        case PROP_AIRCRAFT_RANGE: // 0x1F Max aircraft range
                                avi->max_range = buf->ReadWord();
                                break;

                        default:
                                ret = CommonVehicleChangeInfo(ei, prop, buf);
                                break;
                }
        }

        return ret;
}

/**
 * Define properties for stations
 * @param stdid StationID of the first station tile.
 * @param numinfo Number of subsequent station tiles to change the property for.
 * @param prop The property to change.
 * @param buf The property value.
 * @return ChangeInfoResult.
 */
static ChangeInfoResult StationChangeInfo(uint stid, int numinfo, int prop, ByteReader *buf)
{
        ChangeInfoResult ret = CIR_SUCCESS;

        if (stid + numinfo > NUM_STATIONS_PER_GRF) {
                grfmsg(1, "StationChangeInfo: Station %u is invalid, max %u, ignoring", stid + numinfo, NUM_STATIONS_PER_GRF);
                return CIR_INVALID_ID;
        }

        /* Allocate station specs if necessary */
        if (_cur.grffile->stations == nullptr) _cur.grffile->stations = CallocT<StationSpec*>(NUM_STATIONS_PER_GRF);

        for (int i = 0; i < numinfo; i++) {
                StationSpec *statspec = _cur.grffile->stations[stid + i];

                /* Check that the station we are modifying is defined. */
                if (statspec == nullptr && prop != 0x08) {
                        grfmsg(2, "StationChangeInfo: Attempt to modify undefined station %u, ignoring", stid + i);
                        return CIR_INVALID_ID;
                }

                switch (prop) {
                        case 0x08: { // Class ID
                                StationSpec **spec = &_cur.grffile->stations[stid + i];

                                /* Property 0x08 is special; it is where the station is allocated */
                                if (*spec == nullptr) *spec = CallocT<StationSpec>(1);

                                /* Swap classid because we read it in BE meaning WAYP or DFLT */
                                uint32 classid = buf->ReadDWord();
                                (*spec)->cls_id = StationClass::Allocate(BSWAP32(classid));
                                break;
                        }

                        case 0x09: // Define sprite layout
                                statspec->tiles = buf->ReadExtendedByte();
                                delete[] statspec->renderdata; // delete earlier loaded stuff
                                statspec->renderdata = new NewGRFSpriteLayout[statspec->tiles];

                                for (uint t = 0; t < statspec->tiles; t++) {
                                        NewGRFSpriteLayout *dts = &statspec->renderdata[t];
                                        dts->consistent_max_offset = UINT16_MAX; // Spritesets are unknown, so no limit.

                                        if (buf->HasData(4) && *(uint32*)buf->Data() == 0) {
                                                buf->Skip(4);
                                                extern const DrawTileSprites _station_display_datas_rail[8];
                                                dts->Clone(&_station_display_datas_rail[t % 8]);
                                                continue;
                                        }

                                        ReadSpriteLayoutSprite(buf, false, false, false, GSF_STATIONS, &dts->ground);
                                        /* On error, bail out immediately. Temporary GRF data was already freed */
                                        if (_cur.skip_sprites < 0) return CIR_DISABLED;

                                        static SmallVector<DrawTileSeqStruct, 8> tmp_layout;
                                        tmp_layout.Clear();
                                        for (;;) {
                                                /* no relative bounding box support */
                                                DrawTileSeqStruct *dtss = tmp_layout.Append();
                                                MemSetT(dtss, 0);

                                                dtss->delta_x = buf->ReadByte();
                                                if (dtss->IsTerminator()) break;
                                                dtss->delta_y = buf->ReadByte();
                                                dtss->delta_z = buf->ReadByte();
                                                dtss->size_x = buf->ReadByte();
                                                dtss->size_y = buf->ReadByte();
                                                dtss->size_z = buf->ReadByte();

                                                ReadSpriteLayoutSprite(buf, false, true, false, GSF_STATIONS, &dtss->image);
                                                /* On error, bail out immediately. Temporary GRF data was already freed */
                                                if (_cur.skip_sprites < 0) return CIR_DISABLED;
                                        }
                                        dts->Clone(tmp_layout.Begin());
                                }
                                break;

                        case 0x0A: { // Copy sprite layout
                                byte srcid = buf->ReadByte();
                                const StationSpec *srcstatspec = _cur.grffile->stations[srcid];

                                if (srcstatspec == nullptr) {
                                        grfmsg(1, "StationChangeInfo: Station %u is not defined, cannot copy sprite layout to %u.", srcid, stid + i);
                                        continue;
                                }

                                delete[] statspec->renderdata; // delete earlier loaded stuff

                                statspec->tiles = srcstatspec->tiles;
                                statspec->renderdata = new NewGRFSpriteLayout[statspec->tiles];
                                for (uint t = 0; t < statspec->tiles; t++) {
                                        statspec->renderdata[t].Clone(&srcstatspec->renderdata[t]);
                                }
                                break;
                        }

                        case 0x0B: // Callback mask
                                statspec->callback_mask = buf->ReadByte();
                                break;

                        case 0x0C: // Disallowed number of platforms
                                statspec->disallowed_platforms = buf->ReadByte();
                                break;

                        case 0x0D: // Disallowed platform lengths
                                statspec->disallowed_lengths = buf->ReadByte();
                                break;

                        case 0x0E: // Define custom layout
                                statspec->copied_layouts = false;

                                while (buf->HasData()) {
                                        byte length = buf->ReadByte();
                                        byte number = buf->ReadByte();
                                        StationLayout layout;
                                        uint l, p;

                                        if (length == 0 || number == 0) break;

                                        if (length > statspec->lengths) {
                                                statspec->platforms = ReallocT(statspec->platforms, length);
                                                memset(statspec->platforms + statspec->lengths, 0, length - statspec->lengths);

                                                statspec->layouts = ReallocT(statspec->layouts, length);
                                                memset(statspec->layouts + statspec->lengths, 0,
                                                           (length - statspec->lengths) * sizeof(*statspec->layouts));

                                                statspec->lengths = length;
                                        }
                                        l = length - 1; // index is zero-based

                                        if (number > statspec->platforms[l]) {
                                                statspec->layouts[l] = ReallocT(statspec->layouts[l], number);
                                                /* We expect nullptr being 0 here, but C99 guarantees that. */
                                                memset(statspec->layouts[l] + statspec->platforms[l], 0,
                                                           (number - statspec->platforms[l]) * sizeof(**statspec->layouts));

                                                statspec->platforms[l] = number;
                                        }

                                        p = 0;
                                        layout = MallocT<byte>(length * number);
                                        try {
                                                for (l = 0; l < length; l++) {
                                                        for (p = 0; p < number; p++) {
                                                                layout[l * number + p] = buf->ReadByte();
                                                        }
                                                }
                                        } catch (...) {
                                                free(layout);
                                                throw;
                                        }

                                        l--;
                                        p--;
                                        free(statspec->layouts[l][p]);
                                        statspec->layouts[l][p] = layout;
                                }
                                break;

                        case 0x0F: { // Copy custom layout
                                byte srcid = buf->ReadByte();
                                const StationSpec *srcstatspec = _cur.grffile->stations[srcid];

                                if (srcstatspec == nullptr) {
                                        grfmsg(1, "StationChangeInfo: Station %u is not defined, cannot copy tile layout to %u.", srcid, stid + i);
                                        continue;
                                }

                                statspec->lengths   = srcstatspec->lengths;
                                statspec->platforms = srcstatspec->platforms;
                                statspec->layouts   = srcstatspec->layouts;
                                statspec->copied_layouts = true;
                                break;
                        }

                        case 0x10: // Little/lots cargo threshold
                                statspec->cargo_threshold = buf->ReadWord();
                                break;

                        case 0x11: // Pylon placement
                                statspec->pylons = buf->ReadByte();
                                break;

                        case 0x12: // Cargo types for random triggers
                                statspec->cargo_triggers = buf->ReadDWord();
                                if (_cur.grffile->grf_version >= 7) {
                                        statspec->cargo_triggers = TranslateRefitMask(statspec->cargo_triggers);
                                }
                                break;

                        case 0x13: // General flags
                                statspec->flags = buf->ReadByte();
                                break;

                        case 0x14: // Overhead wire placement
                                statspec->wires = buf->ReadByte();
                                break;

                        case 0x15: // Blocked tiles
                                statspec->blocked = buf->ReadByte();
                                break;

                        case 0x16: // Animation info
                                statspec->animation.frames = buf->ReadByte();
                                statspec->animation.status = buf->ReadByte();
                                break;

                        case 0x17: // Animation speed
                                statspec->animation.speed = buf->ReadByte();
                                break;

                        case 0x18: // Animation triggers
                                statspec->animation.triggers = buf->ReadWord();
                                break;

                        case 0x1A: // Advanced sprite layout
                                statspec->tiles = buf->ReadExtendedByte();
                                delete[] statspec->renderdata; // delete earlier loaded stuff
                                statspec->renderdata = new NewGRFSpriteLayout[statspec->tiles];

                                for (uint t = 0; t < statspec->tiles; t++) {
                                        NewGRFSpriteLayout *dts = &statspec->renderdata[t];
                                        uint num_building_sprites = buf->ReadByte();
                                        /* On error, bail out immediately. Temporary GRF data was already freed */
                                        if (ReadSpriteLayout(buf, num_building_sprites, false, GSF_STATIONS, true, false, dts)) return CIR_DISABLED;
                                }
                                break;

                        default:
                                ret = CIR_UNKNOWN;
                                break;
                }
        }

        return ret;
}

/**
 * Define properties for water features
 * @param id Type of the first water feature.
 * @param numinfo Number of subsequent water feature ids to change the property for.
 * @param prop The property to change.
 * @param buf The property value.
 * @return ChangeInfoResult.
 */
static ChangeInfoResult CanalChangeInfo(uint id, int numinfo, int prop, ByteReader *buf)
{
        ChangeInfoResult ret = CIR_SUCCESS;

        if (id + numinfo > CF_END) {
                grfmsg(1, "CanalChangeInfo: Canal feature %u is invalid, max %u, ignoring", id + numinfo, CF_END);
                return CIR_INVALID_ID;
        }

        for (int i = 0; i < numinfo; i++) {
                CanalProperties *cp = &_cur.grffile->canal_local_properties[id + i];

                switch (prop) {
                        case 0x08:
                                cp->callback_mask = buf->ReadByte();
                                break;

                        case 0x09:
                                cp->flags = buf->ReadByte();
                                break;

                        default:
                                ret = CIR_UNKNOWN;
                                break;
                }
        }

        return ret;
}

/**
 * Define properties for bridges
 * @param brid BridgeID of the bridge.
 * @param numinfo Number of subsequent bridgeIDs to change the property for.
 * @param prop The property to change.
 * @param buf The property value.
 * @return ChangeInfoResult.
 */
static ChangeInfoResult BridgeChangeInfo(uint brid, int numinfo, int prop, ByteReader *buf)
{
        ChangeInfoResult ret = CIR_SUCCESS;

        if (brid + numinfo > MAX_BRIDGES) {
                grfmsg(1, "BridgeChangeInfo: Bridge %u is invalid, max %u, ignoring", brid + numinfo, MAX_BRIDGES);
                return CIR_INVALID_ID;
        }

        for (int i = 0; i < numinfo; i++) {
                BridgeSpec *bridge = &_bridge[brid + i];

                switch (prop) {
                        case 0x08: { // Year of availability
                                /* We treat '0' as always available */
                                byte year = buf->ReadByte();
                                bridge->avail_year = (year > 0 ? ORIGINAL_BASE_YEAR + year : 0);
                                break;
                        }

                        case 0x09: // Minimum length
                                bridge->min_length = buf->ReadByte();
                                break;

                        case 0x0A: // Maximum length
                                bridge->max_length = buf->ReadByte();
                                if (bridge->max_length > 16) bridge->max_length = 0xFFFF;
                                break;

                        case 0x0B: // Cost factor
                                bridge->price = buf->ReadByte();
                                break;

                        case 0x0C: // Maximum speed
                                bridge->speed = buf->ReadWord();
                                break;

                        case 0x0D: { // Bridge sprite tables
                                byte tableid = buf->ReadByte();
                                byte numtables = buf->ReadByte();

                                if (bridge->sprite_table == nullptr) {
                                        /* Allocate memory for sprite table pointers and zero out */
                                        bridge->sprite_table = CallocT<PalSpriteID*>(7);
                                }

                                for (; numtables-- != 0; tableid++) {
                                        if (tableid >= 7) { // skip invalid data
                                                grfmsg(1, "BridgeChangeInfo: Table %d >= 7, skipping", tableid);
                                                for (byte sprite = 0; sprite < 32; sprite++) buf->ReadDWord();
                                                continue;
                                        }

                                        if (bridge->sprite_table[tableid] == nullptr) {
                                                bridge->sprite_table[tableid] = MallocT<PalSpriteID>(32);
                                        }

                                        for (byte sprite = 0; sprite < 32; sprite++) {
                                                SpriteID image = buf->ReadWord();
                                                PaletteID pal  = buf->ReadWord();

                                                bridge->sprite_table[tableid][sprite].sprite = image;
                                                bridge->sprite_table[tableid][sprite].pal    = pal;

                                                MapSpriteMappingRecolour(&bridge->sprite_table[tableid][sprite]);
                                        }
                                }
                                break;
                        }

                        case 0x0E: // Flags; bit 0 - disable far pillars
                                bridge->flags = buf->ReadByte();
                                break;

                        case 0x0F: // Long format year of availability (year since year 0)
                                bridge->avail_year = Clamp(buf->ReadDWord(), MIN_YEAR, MAX_YEAR);
                                break;

                        case 0x10: { // purchase string
                                StringID newone = GetGRFStringID(_cur.grffile->grfid, buf->ReadWord());
                                if (newone != STR_UNDEFINED) bridge->material = newone;
                                break;
                        }

                        case 0x11: // description of bridge with rails or roads
                        case 0x12: {
                                StringID newone = GetGRFStringID(_cur.grffile->grfid, buf->ReadWord());
                                if (newone != STR_UNDEFINED) bridge->transport_name[prop - 0x11] = newone;
                                break;
                        }

                        case 0x13: // 16 bits cost multiplier
                                bridge->price = buf->ReadWord();
                                break;

                        default:
                                ret = CIR_UNKNOWN;
                                break;
                }
        }

        return ret;
}

/**
 * Ignore a house property
 * @param prop Property to read.
 * @param buf Property value.
 * @return ChangeInfoResult.
 */
static ChangeInfoResult IgnoreTownHouseProperty(int prop, ByteReader *buf)
{
        ChangeInfoResult ret = CIR_SUCCESS;

        switch (prop) {
                case 0x09:
                case 0x0B:
                case 0x0C:
                case 0x0D:
                case 0x0E:
                case 0x0F:
                case 0x11:
                case 0x14:
                case 0x15:
                case 0x16:
                case 0x18:
                case 0x19:
                case 0x1A:
                case 0x1B:
                case 0x1C:
                case 0x1D:
                case 0x1F:
                        buf->ReadByte();
                        break;

                case 0x0A:
                case 0x10:
                case 0x12:
                case 0x13:
                case 0x21:
                case 0x22:
                        buf->ReadWord();
                        break;

                case 0x1E:
                        buf->ReadDWord();
                        break;

                case 0x17:
                        for (uint j = 0; j < 4; j++) buf->ReadByte();
                        break;

                case 0x20: {
                        byte count = buf->ReadByte();
                        for (byte j = 0; j < count; j++) buf->ReadByte();
                        break;
                }

                default:
                        ret = CIR_UNKNOWN;
                        break;
        }
        return ret;
}

/**
 * Define properties for houses
 * @param hid HouseID of the house.
 * @param numinfo Number of subsequent houseIDs to change the property for.
 * @param prop The property to change.
 * @param buf The property value.
 * @return ChangeInfoResult.
 */
static ChangeInfoResult TownHouseChangeInfo(uint hid, int numinfo, int prop, ByteReader *buf)
{
        ChangeInfoResult ret = CIR_SUCCESS;

        if (hid + numinfo > NUM_HOUSES_PER_GRF) {
                grfmsg(1, "TownHouseChangeInfo: Too many houses loaded (%u), max (%u). Ignoring.", hid + numinfo, NUM_HOUSES_PER_GRF);
                return CIR_INVALID_ID;
        }

        /* Allocate house specs if they haven't been allocated already. */
        if (_cur.grffile->housespec == nullptr) {
                _cur.grffile->housespec = CallocT<HouseSpec*>(NUM_HOUSES_PER_GRF);
        }

        for (int i = 0; i < numinfo; i++) {
                HouseSpec *housespec = _cur.grffile->housespec[hid + i];

                if (prop != 0x08 && housespec == nullptr) {
                        /* If the house property 08 is not yet set, ignore this property */
                        ChangeInfoResult cir = IgnoreTownHouseProperty(prop, buf);
                        if (cir > ret) ret = cir;
                        continue;
                }

                switch (prop) {
                        case 0x08: { // Substitute building type, and definition of a new house
                                HouseSpec **house = &_cur.grffile->housespec[hid + i];
                                byte subs_id = buf->ReadByte();

                                if (subs_id == 0xFF) {
                                        /* Instead of defining a new house, a substitute house id
                                         * of 0xFF disables the old house with the current id. */
                                        HouseSpec::Get(hid + i)->enabled = false;
                                        continue;
                                } else if (subs_id >= NEW_HOUSE_OFFSET) {
                                        /* The substitute id must be one of the original houses. */
                                        grfmsg(2, "TownHouseChangeInfo: Attempt to use new house %u as substitute house for %u. Ignoring.", subs_id, hid + i);
                                        continue;
                                }

                                /* Allocate space for this house. */
                                if (*house == nullptr) *house = CallocT<HouseSpec>(1);

                                housespec = *house;

                                MemCpyT(housespec, HouseSpec::Get(subs_id));

                                housespec->enabled = true;
                                housespec->grf_prop.local_id = hid + i;
                                housespec->grf_prop.subst_id = subs_id;
                                housespec->grf_prop.grffile = _cur.grffile;
                                housespec->random_colour[0] = 0x04;  // those 4 random colours are the base colour
                                housespec->random_colour[1] = 0x08;  // for all new houses
                                housespec->random_colour[2] = 0x0C;  // they stand for red, blue, orange and green
                                housespec->random_colour[3] = 0x06;

                                /* Make sure that the third cargo type is valid in this
                                 * climate. This can cause problems when copying the properties
                                 * of a house that accepts food, where the new house is valid
                                 * in the temperate climate. */
                                if (!CargoSpec::Get(housespec->accepts_cargo[2])->IsValid()) {
                                        housespec->cargo_acceptance[2] = 0;
                                }

                                _loaded_newgrf_features.has_newhouses = true;
                                break;
                        }

                        case 0x09: // Building flags
                                housespec->building_flags = (BuildingFlags)buf->ReadByte();
                                break;

                        case 0x0A: { // Availability years
                                uint16 years = buf->ReadWord();
                                housespec->min_year = GB(years, 0, 8) > 150 ? MAX_YEAR : ORIGINAL_BASE_YEAR + GB(years, 0, 8);
                                housespec->max_year = GB(years, 8, 8) > 150 ? MAX_YEAR : ORIGINAL_BASE_YEAR + GB(years, 8, 8);
                                break;
                        }

                        case 0x0B: // Population
                                housespec->population = buf->ReadByte();
                                break;

                        case 0x0C: // Mail generation multiplier
                                housespec->mail_generation = buf->ReadByte();
                                break;

                        case 0x0D: // Passenger acceptance
                        case 0x0E: // Mail acceptance
                                housespec->cargo_acceptance[prop - 0x0D] = buf->ReadByte();
                                break;

                        case 0x0F: { // Goods/candy, food/fizzy drinks acceptance
                                int8 goods = buf->ReadByte();

                                /* If value of goods is negative, it means in fact food or, if in toyland, fizzy_drink acceptance.
                                 * Else, we have "standard" 3rd cargo type, goods or candy, for toyland once more */
                                CargoID cid = (goods >= 0) ? ((_settings_game.game_creation.landscape == LT_TOYLAND) ? CT_CANDY : CT_GOODS) :
                                                ((_settings_game.game_creation.landscape == LT_TOYLAND) ? CT_FIZZY_DRINKS : CT_FOOD);

                                /* Make sure the cargo type is valid in this climate. */
                                if (!CargoSpec::Get(cid)->IsValid()) goods = 0;

                                housespec->accepts_cargo[2] = cid;
                                housespec->cargo_acceptance[2] = abs(goods); // but we do need positive value here
                                break;
                        }

                        case 0x10: // Local authority rating decrease on removal
                                housespec->remove_rating_decrease = buf->ReadWord();
                                break;

                        case 0x11: // Removal cost multiplier
                                housespec->removal_cost = buf->ReadByte();
                                break;

                        case 0x12: // Building name ID
                                AddStringForMapping(buf->ReadWord(), &housespec->building_name);
                                break;

                        case 0x13: // Building availability mask
                                housespec->building_availability = (HouseZones)buf->ReadWord();
                                break;

                        case 0x14: // House callback mask
                                housespec->callback_mask |= buf->ReadByte();
                                break;

                        case 0x15: { // House override byte
                                byte override = buf->ReadByte();

                                /* The house being overridden must be an original house. */
                                if (override >= NEW_HOUSE_OFFSET) {
                                        grfmsg(2, "TownHouseChangeInfo: Attempt to override new house %u with house id %u. Ignoring.", override, hid + i);
                                        continue;
                                }

                                _house_mngr.Add(hid + i, _cur.grffile->grfid, override);
                                break;
                        }

                        case 0x16: // Periodic refresh multiplier
                                housespec->processing_time = min(buf->ReadByte(), 63);
                                break;

                        case 0x17: // Four random colours to use
                                for (uint j = 0; j < 4; j++) housespec->random_colour[j] = buf->ReadByte();
                                break;

                        case 0x18: // Relative probability of appearing
                                housespec->probability = buf->ReadByte();
                                break;

                        case 0x19: // Extra flags
                                housespec->extra_flags = (HouseExtraFlags)buf->ReadByte();
                                break;

                        case 0x1A: // Animation frames
                                housespec->animation.frames = buf->ReadByte();
                                housespec->animation.status = GB(housespec->animation.frames, 7, 1);
                                SB(housespec->animation.frames, 7, 1, 0);
                                break;

                        case 0x1B: // Animation speed
                                housespec->animation.speed = Clamp(buf->ReadByte(), 2, 16);
                                break;

                        case 0x1C: // Class of the building type
                                housespec->class_id = AllocateHouseClassID(buf->ReadByte(), _cur.grffile->grfid);
                                break;

                        case 0x1D: // Callback mask part 2
                                housespec->callback_mask |= (buf->ReadByte() << 8);
                                break;

                        case 0x1E: { // Accepted cargo types
                                uint32 cargotypes = buf->ReadDWord();

                                /* Check if the cargo types should not be changed */
                                if (cargotypes == 0xFFFFFFFF) break;

                                for (uint j = 0; j < 3; j++) {
                                        /* Get the cargo number from the 'list' */
                                        uint8 cargo_part = GB(cargotypes, 8 * j, 8);
                                        CargoID cargo = GetCargoTranslation(cargo_part, _cur.grffile);

                                        if (cargo == CT_INVALID) {
                                                /* Disable acceptance of invalid cargo type */
                                                housespec->cargo_acceptance[j] = 0;
                                        } else {
                                                housespec->accepts_cargo[j] = cargo;
                                        }
                                }
                                break;
                        }

                        case 0x1F: // Minimum life span
                                housespec->minimum_life = buf->ReadByte();
                                break;

                        case 0x20: { // Cargo acceptance watch list
                                byte count = buf->ReadByte();
                                for (byte j = 0; j < count; j++) {
                                        CargoID cargo = GetCargoTranslation(buf->ReadByte(), _cur.grffile);
                                        if (cargo != CT_INVALID) SetBit(housespec->watched_cargoes, cargo);
                                }
                                break;
                        }

                        case 0x21: // long introduction year
                                housespec->min_year = buf->ReadWord();
                                break;

                        case 0x22: // long maximum year
                                housespec->max_year = buf->ReadWord();
                                break;

                        default:
                                ret = CIR_UNKNOWN;
                                break;
                }
        }

        return ret;
}

/**
 * Get the language map associated with a given NewGRF and language.
 * @param grfid       The NewGRF to get the map for.
 * @param language_id The (NewGRF) language ID to get the map for.
 * @return The LanguageMap, or nullptr if it couldn't be found.
 */
/* static */ const LanguageMap *LanguageMap::GetLanguageMap(uint32 grfid, uint8 language_id)
{
        /* LanguageID "MAX_LANG", i.e. 7F is any. This language can't have a gender/case mapping, but has to be handled gracefully. */
        const GRFFile *grffile = GetFileByGRFID(grfid);
        return (grffile != nullptr && grffile->language_map != nullptr && language_id < MAX_LANG) ? &grffile->language_map[language_id] : nullptr;
}

/**
 * Load a cargo- or railtype-translation table.
 * @param gvid ID of the global variable. This is basically only checked for zerones.
 * @param numinfo Number of subsequent IDs to change the property for.
 * @param buf The property value.
 * @param [in,out] translation_table Storage location for the translation table.
 * @param name Name of the table for debug output.
 * @return ChangeInfoResult.
 */
template <typename T>
static ChangeInfoResult LoadTranslationTable(uint gvid, int numinfo, ByteReader *buf, T &translation_table, const char *name)
{
        if (gvid != 0) {
                grfmsg(1, "LoadTranslationTable: %s translation table must start at zero", name);
                return CIR_INVALID_ID;
        }

        translation_table.Clear();
        for (int i = 0; i < numinfo; i++) {
                uint32 item = buf->ReadDWord();
                *translation_table.Append() = BSWAP32(item);
        }

        return CIR_SUCCESS;
}

/**
 * Define properties for global variables
 * @param gvid ID of the global variable.
 * @param numinfo Number of subsequent IDs to change the property for.
 * @param prop The property to change.
 * @param buf The property value.
 * @return ChangeInfoResult.
 */
static ChangeInfoResult GlobalVarChangeInfo(uint gvid, int numinfo, int prop, ByteReader *buf)
{
        /* Properties which are handled as a whole */
        switch (prop) {
                case 0x09: // Cargo Translation Table; loading during both reservation and activation stage (in case it is selected depending on defined cargos)
                        return LoadTranslationTable(gvid, numinfo, buf, _cur.grffile->cargo_list, "Cargo");

                case 0x12: // Rail type translation table; loading during both reservation and activation stage (in case it is selected depending on defined railtypes)
                        return LoadTranslationTable(gvid, numinfo, buf, _cur.grffile->railtype_list, "Rail type");

                case 0x16: // Road type translation table; loading during both reservation and activation stage (in case it is selected depending on defined railtypes)
                        return LoadTranslationTable(gvid, numinfo, buf, _cur.grffile->roadtype_list[ROADTYPE_ROAD], "Road type");

                case 0x17: // Tram type translation table; loading during both reservation and activation stage (in case it is selected depending on defined railtypes)
                        return LoadTranslationTable(gvid, numinfo, buf, _cur.grffile->roadtype_list[ROADTYPE_TRAM], "Tram type");

                default:
                        break;
        }

        /* Properties which are handled per item */
        ChangeInfoResult ret = CIR_SUCCESS;
        for (int i = 0; i < numinfo; i++) {
                switch (prop) {
                        case 0x08: { // Cost base factor
                                int factor = buf->ReadByte();
                                uint price = gvid + i;

                                if (price < PR_END) {
                                        _cur.grffile->price_base_multipliers[price] = min<int>(factor - 8, MAX_PRICE_MODIFIER);
                                } else {
                                        grfmsg(1, "GlobalVarChangeInfo: Price %d out of range, ignoring", price);
                                }
                                break;
                        }

                        case 0x0A: { // Currency display names
                                uint curidx = GetNewgrfCurrencyIdConverted(gvid + i);
                                StringID newone = GetGRFStringID(_cur.grffile->grfid, buf->ReadWord());

                                if ((newone != STR_UNDEFINED) && (curidx < CURRENCY_END)) {
                                        _currency_specs[curidx].name = newone;
                                }
                                break;
                        }

                        case 0x0B: { // Currency multipliers
                                uint curidx = GetNewgrfCurrencyIdConverted(gvid + i);
                                uint32 rate = buf->ReadDWord();

                                if (curidx < CURRENCY_END) {
                                        /* TTDPatch uses a multiple of 1000 for its conversion calculations,
                                         * which OTTD does not. For this reason, divide grf value by 1000,
                                         * to be compatible */
                                        _currency_specs[curidx].rate = rate / 1000;
                                } else {
                                        grfmsg(1, "GlobalVarChangeInfo: Currency multipliers %d out of range, ignoring", curidx);
                                }
                                break;
                        }

                        case 0x0C: { // Currency options
                                uint curidx = GetNewgrfCurrencyIdConverted(gvid + i);
                                uint16 options = buf->ReadWord();

                                if (curidx < CURRENCY_END) {
                                        _currency_specs[curidx].separator[0] = GB(options, 0, 8);
                                        _currency_specs[curidx].separator[1] = '\0';
                                        /* By specifying only one bit, we prevent errors,
                                         * since newgrf specs said that only 0 and 1 can be set for symbol_pos */
                                        _currency_specs[curidx].symbol_pos = GB(options, 8, 1);
                                } else {
                                        grfmsg(1, "GlobalVarChangeInfo: Currency option %d out of range, ignoring", curidx);
                                }
                                break;
                        }

                        case 0x0D: { // Currency prefix symbol
                                uint curidx = GetNewgrfCurrencyIdConverted(gvid + i);
                                uint32 tempfix = buf->ReadDWord();

                                if (curidx < CURRENCY_END) {
                                        memcpy(_currency_specs[curidx].prefix, &tempfix, 4);
                                        _currency_specs[curidx].prefix[4] = 0;
                                } else {
                                        grfmsg(1, "GlobalVarChangeInfo: Currency symbol %d out of range, ignoring", curidx);
                                }
                                break;
                        }

                        case 0x0E: { // Currency suffix symbol
                                uint curidx = GetNewgrfCurrencyIdConverted(gvid + i);
                                uint32 tempfix = buf->ReadDWord();

                                if (curidx < CURRENCY_END) {
                                        memcpy(&_currency_specs[curidx].suffix, &tempfix, 4);
                                        _currency_specs[curidx].suffix[4] = 0;
                                } else {
                                        grfmsg(1, "GlobalVarChangeInfo: Currency symbol %d out of range, ignoring", curidx);
                                }
                                break;
                        }

                        case 0x0F: { //  Euro introduction dates
                                uint curidx = GetNewgrfCurrencyIdConverted(gvid + i);
                                Year year_euro = buf->ReadWord();

                                if (curidx < CURRENCY_END) {
                                        _currency_specs[curidx].to_euro = year_euro;
                                } else {
                                        grfmsg(1, "GlobalVarChangeInfo: Euro intro date %d out of range, ignoring", curidx);
                                }
                                break;
                        }

                        case 0x10: // Snow line height table
                                if (numinfo > 1 || IsSnowLineSet()) {
                                        grfmsg(1, "GlobalVarChangeInfo: The snowline can only be set once (%d)", numinfo);
                                } else if (buf->Remaining() < SNOW_LINE_MONTHS * SNOW_LINE_DAYS) {
                                        grfmsg(1, "GlobalVarChangeInfo: Not enough entries set in the snowline table (" PRINTF_SIZE ")", buf->Remaining());
                                } else {
                                        byte table[SNOW_LINE_MONTHS][SNOW_LINE_DAYS];

                                        for (uint i = 0; i < SNOW_LINE_MONTHS; i++) {
                                                for (uint j = 0; j < SNOW_LINE_DAYS; j++) {
                                                        table[i][j] = buf->ReadByte();
                                                        if (_cur.grffile->grf_version >= 8) {
                                                                if (table[i][j] != 0xFF) table[i][j] = table[i][j] * (1 + _settings_game.construction.max_heightlevel) / 256;
                                                        } else {
                                                                if (table[i][j] >= 128) {
                                                                        /* no snow */
                                                                        table[i][j] = 0xFF;
                                                                } else {
                                                                        table[i][j] = table[i][j] * (1 + _settings_game.construction.max_heightlevel) / 128;
                                                                }
                                                        }
                                                }
                                        }
                                        SetSnowLine(table);
                                }
                                break;

                        case 0x11: // GRF match for engine allocation
                                /* This is loaded during the reservation stage, so just skip it here. */
                                /* Each entry is 8 bytes. */
                                buf->Skip(8);
                                break;

                        case 0x13:   // Gender translation table
                        case 0x14:   // Case translation table
                        case 0x15: { // Plural form translation
                                uint curidx = gvid + i; // The current index, i.e. language.
                                const LanguageMetadata *lang = curidx < MAX_LANG ? GetLanguage(curidx) : nullptr;
                                if (lang == nullptr) {
                                        grfmsg(1, "GlobalVarChangeInfo: Language %d is not known, ignoring", curidx);
                                        /* Skip over the data. */
                                        if (prop == 0x15) {
                                                buf->ReadByte();
                                        } else {
                                                while (buf->ReadByte() != 0) {
                                                        buf->ReadString();
                                                }
                                        }
                                        break;
                                }

                                if (_cur.grffile->language_map == nullptr) _cur.grffile->language_map = new LanguageMap[MAX_LANG];

                                if (prop == 0x15) {
                                        uint plural_form = buf->ReadByte();
                                        if (plural_form >= LANGUAGE_MAX_PLURAL) {
                                                grfmsg(1, "GlobalVarChanceInfo: Plural form %d is out of range, ignoring", plural_form);
                                        } else {
                                                _cur.grffile->language_map[curidx].plural_form = plural_form;
                                        }
                                        break;
                                }

                                byte newgrf_id = buf->ReadByte(); // The NewGRF (custom) identifier.
                                while (newgrf_id != 0) {
                                        const char *name = buf->ReadString(); // The name for the OpenTTD identifier.

                                        /* We'll just ignore the UTF8 identifier character. This is (fairly)
                                         * safe as OpenTTD's strings gender/cases are usually in ASCII which
                                         * is just a subset of UTF8, or they need the bigger UTF8 characters
                                         * such as Cyrillic. Thus we will simply assume they're all UTF8. */
                                        WChar c;
                                        size_t len = Utf8Decode(&c, name);
                                        if (c == NFO_UTF8_IDENTIFIER) name += len;

                                        LanguageMap::Mapping map;
                                        map.newgrf_id = newgrf_id;
                                        if (prop == 0x13) {
                                                map.openttd_id = lang->GetGenderIndex(name);
                                                if (map.openttd_id >= MAX_NUM_GENDERS) {
                                                        grfmsg(1, "GlobalVarChangeInfo: Gender name %s is not known, ignoring", name);
                                                } else {
                                                        *_cur.grffile->language_map[curidx].gender_map.Append() = map;
                                                }
                                        } else {
                                                map.openttd_id = lang->GetCaseIndex(name);
                                                if (map.openttd_id >= MAX_NUM_CASES) {
                                                        grfmsg(1, "GlobalVarChangeInfo: Case name %s is not known, ignoring", name);
                                                } else {
                                                        *_cur.grffile->language_map[curidx].case_map.Append() = map;
                                                }
                                        }
                                        newgrf_id = buf->ReadByte();
                                }
                                break;
                        }

                        default:
                                ret = CIR_UNKNOWN;
                                break;
                }
        }

        return ret;
}

static ChangeInfoResult GlobalVarReserveInfo(uint gvid, int numinfo, int prop, ByteReader *buf)
{
        /* Properties which are handled as a whole */
        switch (prop) {
                case 0x09: // Cargo Translation Table; loading during both reservation and activation stage (in case it is selected depending on defined cargos)
                        return LoadTranslationTable(gvid, numinfo, buf, _cur.grffile->cargo_list, "Cargo");

                case 0x12: // Rail type translation table; loading during both reservation and activation stage (in case it is selected depending on defined railtypes)
                        return LoadTranslationTable(gvid, numinfo, buf, _cur.grffile->railtype_list, "Rail type");

                case 0x16: // Road type translation table; loading during both reservation and activation stage (in case it is selected depending on defined roadtypes)
                        return LoadTranslationTable(gvid, numinfo, buf, _cur.grffile->roadtype_list[ROADTYPE_ROAD], "Road type");

                case 0x17: // Tram type translation table; loading during both reservation and activation stage (in case it is selected depending on defined tramtypes)
                        return LoadTranslationTable(gvid, numinfo, buf, _cur.grffile->roadtype_list[ROADTYPE_TRAM], "Tram type");

                default:
                        break;
        }

        /* Properties which are handled per item */
        ChangeInfoResult ret = CIR_SUCCESS;
        for (int i = 0; i < numinfo; i++) {
                switch (prop) {
                        case 0x08: // Cost base factor
                        case 0x15: // Plural form translation
                                buf->ReadByte();
                                break;

                        case 0x0A: // Currency display names
                        case 0x0C: // Currency options
                        case 0x0F: // Euro introduction dates
                                buf->ReadWord();
                                break;

                        case 0x0B: // Currency multipliers
                        case 0x0D: // Currency prefix symbol
                        case 0x0E: // Currency suffix symbol
                                buf->ReadDWord();
                                break;

                        case 0x10: // Snow line height table
                                buf->Skip(SNOW_LINE_MONTHS * SNOW_LINE_DAYS);
                                break;

                        case 0x11: { // GRF match for engine allocation
                                uint32 s = buf->ReadDWord();
                                uint32 t = buf->ReadDWord();
                                SetNewGRFOverride(s, t);
                                break;
                        }

                        case 0x13: // Gender translation table
                        case 0x14: // Case translation table
                                while (buf->ReadByte() != 0) {
                                        buf->ReadString();
                                }
                                break;

                        default:
                                ret = CIR_UNKNOWN;
                                break;
                }
        }

        return ret;
}


/**
 * Define properties for cargoes
 * @param cid Local ID of the cargo.
 * @param numinfo Number of subsequent IDs to change the property for.
 * @param prop The property to change.
 * @param buf The property value.
 * @return ChangeInfoResult.
 */
static ChangeInfoResult CargoChangeInfo(uint cid, int numinfo, int prop, ByteReader *buf)
{
        ChangeInfoResult ret = CIR_SUCCESS;

        if (cid + numinfo > NUM_CARGO) {
                grfmsg(2, "CargoChangeInfo: Cargo type %d out of range (max %d)", cid + numinfo, NUM_CARGO - 1);
                return CIR_INVALID_ID;
        }

        for (int i = 0; i < numinfo; i++) {
                CargoSpec *cs = CargoSpec::Get(cid + i);

                switch (prop) {
                        case 0x08: // Bit number of cargo
                                cs->bitnum = buf->ReadByte();
                                if (cs->IsValid()) {
                                        cs->grffile = _cur.grffile;
                                        SetBit(_cargo_mask, cid + i);
                                } else {
                                        ClrBit(_cargo_mask, cid + i);
                                }
                                break;

                        case 0x09: // String ID for cargo type name
                                AddStringForMapping(buf->ReadWord(), &cs->name);
                                break;

                        case 0x0A: // String for 1 unit of cargo
                                AddStringForMapping(buf->ReadWord(), &cs->name_single);
                                break;

                        case 0x0B: // String for singular quantity of cargo (e.g. 1 tonne of coal)
                        case 0x1B: // String for cargo units
                                /* String for units of cargo. This is different in OpenTTD
                                 * (e.g. tonnes) to TTDPatch (e.g. {COMMA} tonne of coal).
                                 * Property 1B is used to set OpenTTD's behaviour. */
                                AddStringForMapping(buf->ReadWord(), &cs->units_volume);
                                break;

                        case 0x0C: // String for plural quantity of cargo (e.g. 10 tonnes of coal)
                        case 0x1C: // String for any amount of cargo
                                /* Strings for an amount of cargo. This is different in OpenTTD
                                 * (e.g. {WEIGHT} of coal) to TTDPatch (e.g. {COMMA} tonnes of coal).
                                 * Property 1C is used to set OpenTTD's behaviour. */
                                AddStringForMapping(buf->ReadWord(), &cs->quantifier);
                                break;

                        case 0x0D: // String for two letter cargo abbreviation
                                AddStringForMapping(buf->ReadWord(), &cs->abbrev);
                                break;

                        case 0x0E: // Sprite ID for cargo icon
                                cs->sprite = buf->ReadWord();
                                break;

                        case 0x0F: // Weight of one unit of cargo
                                cs->weight = buf->ReadByte();
                                break;

                        case 0x10: // Used for payment calculation
                                cs->transit_days[0] = buf->ReadByte();
                                break;

                        case 0x11: // Used for payment calculation
                                cs->transit_days[1] = buf->ReadByte();
                                break;

                        case 0x12: // Base cargo price
                                cs->initial_payment = buf->ReadDWord();
                                break;

                        case 0x13: // Colour for station rating bars
                                cs->rating_colour = buf->ReadByte();
                                break;

                        case 0x14: // Colour for cargo graph
                                cs->legend_colour = buf->ReadByte();
                                break;

                        case 0x15: // Freight status
                                cs->is_freight = (buf->ReadByte() != 0);
                                break;

                        case 0x16: // Cargo classes
                                cs->classes = buf->ReadWord();
                                break;

                        case 0x17: // Cargo label
                                cs->label = buf->ReadDWord();
                                cs->label = BSWAP32(cs->label);
                                break;

                        case 0x18: { // Town growth substitute type
                                uint8 substitute_type = buf->ReadByte();

                                switch (substitute_type) {
                                        case 0x00: cs->town_effect = TE_PASSENGERS; break;
                                        case 0x02: cs->town_effect = TE_MAIL; break;
                                        case 0x05: cs->town_effect = TE_GOODS; break;
                                        case 0x09: cs->town_effect = TE_WATER; break;
                                        case 0x0B: cs->town_effect = TE_FOOD; break;
                                        default:
                                                grfmsg(1, "CargoChangeInfo: Unknown town growth substitute value %d, setting to none.", substitute_type);
                                                FALLTHROUGH;
                                        case 0xFF: cs->town_effect = TE_NONE; break;
                                }
                                break;
                        }

                        case 0x19: // Town growth coefficient
                                cs->multipliertowngrowth = buf->ReadWord();
                                break;

                        case 0x1A: // Bitmask of callbacks to use
                                cs->callback_mask = buf->ReadByte();
                                break;

                        case 0x1D: // Vehicle capacity muliplier
                                cs->multiplier = max<uint16>(1u, buf->ReadWord());
                                break;

                        default:
                                ret = CIR_UNKNOWN;
                                break;
                }
        }

        return ret;
}


/**
 * Define properties for sound effects
 * @param sid Local ID of the sound.
 * @param numinfo Number of subsequent IDs to change the property for.
 * @param prop The property to change.
 * @param buf The property value.
 * @return ChangeInfoResult.
 */
static ChangeInfoResult SoundEffectChangeInfo(uint sid, int numinfo, int prop, ByteReader *buf)
{
        ChangeInfoResult ret = CIR_SUCCESS;

        if (_cur.grffile->sound_offset == 0) {
                grfmsg(1, "SoundEffectChangeInfo: No effects defined, skipping");
                return CIR_INVALID_ID;
        }

        if (sid + numinfo - ORIGINAL_SAMPLE_COUNT > _cur.grffile->num_sounds) {
                grfmsg(1, "SoundEffectChangeInfo: Attempting to change undefined sound effect (%u), max (%u). Ignoring.", sid + numinfo, ORIGINAL_SAMPLE_COUNT + _cur.grffile->num_sounds);
                return CIR_INVALID_ID;
        }

        for (int i = 0; i < numinfo; i++) {
                SoundEntry *sound = GetSound(sid + i + _cur.grffile->sound_offset - ORIGINAL_SAMPLE_COUNT);

                switch (prop) {
                        case 0x08: // Relative volume
                                sound->volume = buf->ReadByte();
                                break;

                        case 0x09: // Priority
                                sound->priority = buf->ReadByte();
                                break;

                        case 0x0A: { // Override old sound
                                SoundID orig_sound = buf->ReadByte();

                                if (orig_sound >= ORIGINAL_SAMPLE_COUNT) {
                                        grfmsg(1, "SoundEffectChangeInfo: Original sound %d not defined (max %d)", orig_sound, ORIGINAL_SAMPLE_COUNT);
                                } else {
                                        SoundEntry *old_sound = GetSound(orig_sound);

                                        /* Literally copy the data of the new sound over the original */
                                        *old_sound = *sound;
                                }
                                break;
                        }

                        default:
                                ret = CIR_UNKNOWN;
                                break;
                }
        }

        return ret;
}

/**
 * Ignore an industry tile property
 * @param prop The property to ignore.
 * @param buf The property value.
 * @return ChangeInfoResult.
 */
static ChangeInfoResult IgnoreIndustryTileProperty(int prop, ByteReader *buf)
{
        ChangeInfoResult ret = CIR_SUCCESS;

        switch (prop) {
                case 0x09:
                case 0x0D:
                case 0x0E:
                case 0x10:
                case 0x11:
                case 0x12:
                        buf->ReadByte();
                        break;

                case 0x0A:
                case 0x0B:
                case 0x0C:
                case 0x0F:
                        buf->ReadWord();
                        break;

                default:
                        ret = CIR_UNKNOWN;
                        break;
        }
        return ret;
}

/**
 * Define properties for industry tiles
 * @param indtid Local ID of the industry tile.
 * @param numinfo Number of subsequent industry tile IDs to change the property for.
 * @param prop The property to change.
 * @param buf The property value.
 * @return ChangeInfoResult.
 */
static ChangeInfoResult IndustrytilesChangeInfo(uint indtid, int numinfo, int prop, ByteReader *buf)
{
        ChangeInfoResult ret = CIR_SUCCESS;

        if (indtid + numinfo > NUM_INDUSTRYTILES_PER_GRF) {
                grfmsg(1, "IndustryTilesChangeInfo: Too many industry tiles loaded (%u), max (%u). Ignoring.", indtid + numinfo, NUM_INDUSTRYTILES_PER_GRF);
                return CIR_INVALID_ID;
        }

        /* Allocate industry tile specs if they haven't been allocated already. */
        if (_cur.grffile->indtspec == nullptr) {
                _cur.grffile->indtspec = CallocT<IndustryTileSpec*>(NUM_INDUSTRYTILES_PER_GRF);
        }

        for (int i = 0; i < numinfo; i++) {
                IndustryTileSpec *tsp = _cur.grffile->indtspec[indtid + i];

                if (prop != 0x08 && tsp == nullptr) {
                        ChangeInfoResult cir = IgnoreIndustryTileProperty(prop, buf);
                        if (cir > ret) ret = cir;
                        continue;
                }

                switch (prop) {
                        case 0x08: { // Substitute industry tile type
                                IndustryTileSpec **tilespec = &_cur.grffile->indtspec[indtid + i];
                                byte subs_id = buf->ReadByte();

                                if (subs_id >= NEW_INDUSTRYTILEOFFSET) {
                                        /* The substitute id must be one of the original industry tile. */
                                        grfmsg(2, "IndustryTilesChangeInfo: Attempt to use new industry tile %u as substitute industry tile for %u. Ignoring.", subs_id, indtid + i);
                                        continue;
                                }

                                /* Allocate space for this industry. */
                                if (*tilespec == nullptr) {
                                        *tilespec = CallocT<IndustryTileSpec>(1);
                                        tsp = *tilespec;

                                        memcpy(tsp, &_industry_tile_specs[subs_id], sizeof(_industry_tile_specs[subs_id]));
                                        tsp->enabled = true;

                                        /* A copied tile should not have the animation infos copied too.
                                         * The anim_state should be left untouched, though
                                         * It is up to the author to animate them himself */
                                        tsp->anim_production = INDUSTRYTILE_NOANIM;
                                        tsp->anim_next = INDUSTRYTILE_NOANIM;

                                        tsp->grf_prop.local_id = indtid + i;
                                        tsp->grf_prop.subst_id = subs_id;
                                        tsp->grf_prop.grffile = _cur.grffile;
                                        _industile_mngr.AddEntityID(indtid + i, _cur.grffile->grfid, subs_id); // pre-reserve the tile slot
                                }
                                break;
                        }

                        case 0x09: { // Industry tile override
                                byte ovrid = buf->ReadByte();

                                /* The industry being overridden must be an original industry. */
                                if (ovrid >= NEW_INDUSTRYTILEOFFSET) {
                                        grfmsg(2, "IndustryTilesChangeInfo: Attempt to override new industry tile %u with industry tile id %u. Ignoring.", ovrid, indtid + i);
                                        continue;
                                }

                                _industile_mngr.Add(indtid + i, _cur.grffile->grfid, ovrid);
                                break;
                        }

                        case 0x0A: // Tile acceptance
                        case 0x0B:
                        case 0x0C: {
                                uint16 acctp = buf->ReadWord();
                                tsp->accepts_cargo[prop - 0x0A] = GetCargoTranslation(GB(acctp, 0, 8), _cur.grffile);
                                tsp->acceptance[prop - 0x0A] = GB(acctp, 8, 8);
                                break;
                        }

                        case 0x0D: // Land shape flags
                                tsp->slopes_refused = (Slope)buf->ReadByte();
                                break;

                        case 0x0E: // Callback mask
                                tsp->callback_mask = buf->ReadByte();
                                break;

                        case 0x0F: // Animation information
                                tsp->animation.frames = buf->ReadByte();
                                tsp->animation.status = buf->ReadByte();
                                break;

                        case 0x10: // Animation speed
                                tsp->animation.speed = buf->ReadByte();
                                break;

                        case 0x11: // Triggers for callback 25
                                tsp->animation.triggers = buf->ReadByte();
                                break;

                        case 0x12: // Special flags
                                tsp->special_flags = (IndustryTileSpecialFlags)buf->ReadByte();
                                break;

                        default:
                                ret = CIR_UNKNOWN;
                                break;
                }
        }

        return ret;
}

/**
 * Ignore an industry property
 * @param prop The property to ignore.
 * @param buf The property value.
 * @return ChangeInfoResult.
 */
static ChangeInfoResult IgnoreIndustryProperty(int prop, ByteReader *buf)
{
        ChangeInfoResult ret = CIR_SUCCESS;

        switch (prop) {
                case 0x09:
                case 0x0B:
                case 0x0F:
                case 0x12:
                case 0x13:
                case 0x14:
                case 0x17:
                case 0x18:
                case 0x19:
                case 0x21:
                case 0x22:
                        buf->ReadByte();
                        break;

                case 0x0C:
                case 0x0D:
                case 0x0E:
                case 0x10:
                case 0x1B:
                case 0x1F:
                case 0x24:
                        buf->ReadWord();
                        break;

                case 0x11:
                case 0x1A:
                case 0x1C:
                case 0x1D:
                case 0x1E:
                case 0x20:
                case 0x23:
                        buf->ReadDWord();
                        break;

                case 0x0A: {
                        byte num_table = buf->ReadByte();
                        for (byte j = 0; j < num_table; j++) {
                                for (uint k = 0;; k++) {
                                        byte x = buf->ReadByte();
                                        if (x == 0xFE && k == 0) {
                                                buf->ReadByte();
                                                buf->ReadByte();
                                                break;
                                        }

                                        byte y = buf->ReadByte();
                                        if (x == 0 && y == 0x80) break;

                                        byte gfx = buf->ReadByte();
                                        if (gfx == 0xFE) buf->ReadWord();
                                }
                        }
                        break;
                }

                case 0x16:
                        for (byte j = 0; j < 3; j++) buf->ReadByte();
                        break;

                case 0x15: {
                        byte number_of_sounds = buf->ReadByte();
                        for (uint8 j = 0; j < number_of_sounds; j++) {
                                buf->ReadByte();
                        }
                        break;
                }

                default:
                        ret = CIR_UNKNOWN;
                        break;
        }
        return ret;
}

/**
 * Validate the industry layout; e.g. to prevent duplicate tiles.
 * @param layout The layout to check.
 * @param size The size of the layout.
 * @return True if the layout is deemed valid.
 */
static bool ValidateIndustryLayout(const IndustryTileTable *layout, int size)
{
        for (int i = 0; i < size - 1; i++) {
                for (int j = i + 1; j < size; j++) {
                        if (layout[i].ti.x == layout[j].ti.x &&
                                        layout[i].ti.y == layout[j].ti.y) {
                                return false;
                        }
                }
        }
        return true;
}

/** Clean the tile table of the IndustrySpec if it's needed. */
static void CleanIndustryTileTable(IndustrySpec *ind)
{
        if (HasBit(ind->cleanup_flag, CLEAN_TILELAYOUT) && ind->table != nullptr) {
                for (int j = 0; j < ind->num_table; j++) {
                        /* remove the individual layouts */
                        free(ind->table[j]);
                }
                /* remove the layouts pointers */
                free(ind->table);
                ind->table = nullptr;
        }
}

/**
 * Define properties for industries
 * @param indid Local ID of the industry.
 * @param numinfo Number of subsequent industry IDs to change the property for.
 * @param prop The property to change.
 * @param buf The property value.
 * @return ChangeInfoResult.
 */
static ChangeInfoResult IndustriesChangeInfo(uint indid, int numinfo, int prop, ByteReader *buf)
{
        ChangeInfoResult ret = CIR_SUCCESS;

        if (indid + numinfo > NUM_INDUSTRYTYPES_PER_GRF) {
                grfmsg(1, "IndustriesChangeInfo: Too many industries loaded (%u), max (%u). Ignoring.", indid + numinfo, NUM_INDUSTRYTYPES_PER_GRF);
                return CIR_INVALID_ID;
        }

        /* Allocate industry specs if they haven't been allocated already. */
        if (_cur.grffile->industryspec == nullptr) {
                _cur.grffile->industryspec = CallocT<IndustrySpec*>(NUM_INDUSTRYTYPES_PER_GRF);
        }

        for (int i = 0; i < numinfo; i++) {
                IndustrySpec *indsp = _cur.grffile->industryspec[indid + i];

                if (prop != 0x08 && indsp == nullptr) {
                        ChangeInfoResult cir = IgnoreIndustryProperty(prop, buf);
                        if (cir > ret) ret = cir;
                        continue;
                }

                switch (prop) {
                        case 0x08: { // Substitute industry type
                                IndustrySpec **indspec = &_cur.grffile->industryspec[indid + i];
                                byte subs_id = buf->ReadByte();

                                if (subs_id == 0xFF) {
                                        /* Instead of defining a new industry, a substitute industry id
                                         * of 0xFF disables the old industry with the current id. */
                                        _industry_specs[indid + i].enabled = false;
                                        continue;
                                } else if (subs_id >= NEW_INDUSTRYOFFSET) {
                                        /* The substitute id must be one of the original industry. */
                                        grfmsg(2, "_industry_specs: Attempt to use new industry %u as substitute industry for %u. Ignoring.", subs_id, indid + i);
                                        continue;
                                }

                                /* Allocate space for this industry.
                                 * Only need to do it once. If ever it is called again, it should not
                                 * do anything */
                                if (*indspec == nullptr) {
                                        *indspec = CallocT<IndustrySpec>(1);
                                        indsp = *indspec;

                                        memcpy(indsp, &_origin_industry_specs[subs_id], sizeof(_industry_specs[subs_id]));
                                        indsp->enabled = true;
                                        indsp->grf_prop.local_id = indid + i;
                                        indsp->grf_prop.subst_id = subs_id;
                                        indsp->grf_prop.grffile = _cur.grffile;
                                        /* If the grf industry needs to check its surounding upon creation, it should
                                         * rely on callbacks, not on the original placement functions */
                                        indsp->check_proc = CHECK_NOTHING;
                                }
                                break;
                        }

                        case 0x09: { // Industry type override
                                byte ovrid = buf->ReadByte();

                                /* The industry being overridden must be an original industry. */
                                if (ovrid >= NEW_INDUSTRYOFFSET) {
                                        grfmsg(2, "IndustriesChangeInfo: Attempt to override new industry %u with industry id %u. Ignoring.", ovrid, indid + i);
                                        continue;
                                }
                                indsp->grf_prop.override = ovrid;
                                _industry_mngr.Add(indid + i, _cur.grffile->grfid, ovrid);
                                break;
                        }

                        case 0x0A: { // Set industry layout(s)
                                byte new_num_layouts = buf->ReadByte(); // Number of layaouts
                                /* We read the total size in bytes, but we can't rely on the
                                 * newgrf to provide a sane value. First assume the value is
                                 * sane but later on we make sure we enlarge the array if the
                                 * newgrf contains more data. Each tile uses either 3 or 5
                                 * bytes, so to play it safe we assume 3. */
                                uint32 def_num_tiles = buf->ReadDWord() / 3 + 1;
                                IndustryTileTable **tile_table = CallocT<IndustryTileTable*>(new_num_layouts); // Table with tiles to compose an industry
                                IndustryTileTable *itt = CallocT<IndustryTileTable>(def_num_tiles); // Temporary array to read the tile layouts from the GRF
                                uint size;
                                const IndustryTileTable *copy_from;

                                try {
                                        for (byte j = 0; j < new_num_layouts; j++) {
                                                for (uint k = 0;; k++) {
                                                        if (k >= def_num_tiles) {
                                                                grfmsg(3, "IndustriesChangeInfo: Incorrect size for industry tile layout definition for industry %u.", indid);
                                                                /* Size reported by newgrf was not big enough so enlarge the array. */
                                                                def_num_tiles *= 2;
                                                                itt = ReallocT<IndustryTileTable>(itt, def_num_tiles);
                                                        }

                                                        itt[k].ti.x = buf->ReadByte(); // Offsets from northermost tile

                                                        if (itt[k].ti.x == 0xFE && k == 0) {
                                                                /* This means we have to borrow the layout from an old industry */
                                                                IndustryType type = buf->ReadByte();  // industry holding required layout
                                                                byte laynbr = buf->ReadByte();        // layout number to borrow

                                                                copy_from = _origin_industry_specs[type].table[laynbr];
                                                                for (size = 1;; size++) {
                                                                        if (copy_from[size - 1].ti.x == -0x80 && copy_from[size - 1].ti.y == 0) break;
                                                                }
                                                                break;
                                                        }

                                                        itt[k].ti.y = buf->ReadByte(); // Or table definition finalisation

                                                        if (itt[k].ti.x == 0 && itt[k].ti.y == 0x80) {
                                                                /*  Not the same terminator.  The one we are using is rather
                                                                 x = -80, y = x .  So, adjust it. */
                                                                itt[k].ti.x = -0x80;
                                                                itt[k].ti.y =  0;
                                                                itt[k].gfx  =  0;

                                                                size = k + 1;
                                                                copy_from = itt;
                                                                break;
                                                        }

                                                        itt[k].gfx = buf->ReadByte();

                                                        if (itt[k].gfx == 0xFE) {
                                                                /* Use a new tile from this GRF */
                                                                int local_tile_id = buf->ReadWord();

                                                                /* Read the ID from the _industile_mngr. */
                                                                int tempid = _industile_mngr.GetID(local_tile_id, _cur.grffile->grfid);

                                                                if (tempid == INVALID_INDUSTRYTILE) {
                                                                        grfmsg(2, "IndustriesChangeInfo: Attempt to use industry tile %u with industry id %u, not yet defined. Ignoring.", local_tile_id, indid);
                                                                } else {
                                                                        /* Declared as been valid, can be used */
                                                                        itt[k].gfx = tempid;
                                                                        size = k + 1;
                                                                        copy_from = itt;
                                                                }
                                                        } else if (itt[k].gfx == 0xFF) {
                                                                itt[k].ti.x = (int8)GB(itt[k].ti.x, 0, 8);
                                                                itt[k].ti.y = (int8)GB(itt[k].ti.y, 0, 8);

                                                                /* When there were only 256x256 maps, TileIndex was a uint16 and
                                                                 * itt[k].ti was just a TileIndexDiff that was added to it.
                                                                 * As such negative "x" values were shifted into the "y" position.
                                                                 *   x = -1, y = 1 -> x = 255, y = 0
                                                                 * Since GRF version 8 the position is interpreted as pair of independent int8.
                                                                 * For GRF version < 8 we need to emulate the old shifting behaviour.
                                                                 */
                                                                if (_cur.grffile->grf_version < 8 && itt[k].ti.x < 0) itt[k].ti.y += 1;
                                                        }
                                                }

                                                if (!ValidateIndustryLayout(copy_from, size)) {
                                                        /* The industry layout was not valid, so skip this one. */
                                                        grfmsg(1, "IndustriesChangeInfo: Invalid industry layout for industry id %u. Ignoring", indid);
                                                        new_num_layouts--;
                                                        j--;
                                                } else {
                                                        tile_table[j] = CallocT<IndustryTileTable>(size);
                                                        memcpy(tile_table[j], copy_from, sizeof(*copy_from) * size);
                                                }
                                        }
                                } catch (...) {
                                        for (int i = 0; i < new_num_layouts; i++) {
                                                free(tile_table[i]);
                                        }
                                        free(tile_table);
                                        free(itt);
                                        throw;
                                }

                                /* Clean the tile table if it was already set by a previous prop A. */
                                CleanIndustryTileTable(indsp);
                                /* Install final layout construction in the industry spec */
                                indsp->num_table = new_num_layouts;
                                indsp->table = tile_table;
                                SetBit(indsp->cleanup_flag, CLEAN_TILELAYOUT);
                                free(itt);
                                break;
                        }

                        case 0x0B: // Industry production flags
                                indsp->life_type = (IndustryLifeType)buf->ReadByte();
                                break;

                        case 0x0C: // Industry closure message
                                AddStringForMapping(buf->ReadWord(), &indsp->closure_text);
                                break;

                        case 0x0D: // Production increase message
                                AddStringForMapping(buf->ReadWord(), &indsp->production_up_text);
                                break;

                        case 0x0E: // Production decrease message
                                AddStringForMapping(buf->ReadWord(), &indsp->production_down_text);
                                break;

                        case 0x0F: // Fund cost multiplier
                                indsp->cost_multiplier = buf->ReadByte();
                                break;

                        case 0x10: // Production cargo types
                                for (byte j = 0; j < 2; j++) {
                                        indsp->produced_cargo[j] = GetCargoTranslation(buf->ReadByte(), _cur.grffile);
                                }
                                break;

                        case 0x11: // Acceptance cargo types
                                for (byte j = 0; j < 3; j++) {
                                        indsp->accepts_cargo[j] = GetCargoTranslation(buf->ReadByte(), _cur.grffile);
                                }
                                buf->ReadByte(); // Unnused, eat it up
                                break;

                        case 0x12: // Production multipliers
                        case 0x13:
                                indsp->production_rate[prop - 0x12] = buf->ReadByte();
                                break;

                        case 0x14: // Minimal amount of cargo distributed
                                indsp->minimal_cargo = buf->ReadByte();
                                break;

                        case 0x15: { // Random sound effects
                                indsp->number_of_sounds = buf->ReadByte();
                                uint8 *sounds = MallocT<uint8>(indsp->number_of_sounds);

                                try {
                                        for (uint8 j = 0; j < indsp->number_of_sounds; j++) {
                                                sounds[j] = buf->ReadByte();
                                        }
                                } catch (...) {
                                        free(sounds);
                                        throw;
                                }

                                if (HasBit(indsp->cleanup_flag, CLEAN_RANDOMSOUNDS)) {
                                        free(indsp->random_sounds);
                                }
                                indsp->random_sounds = sounds;
                                SetBit(indsp->cleanup_flag, CLEAN_RANDOMSOUNDS);
                                break;
                        }

                        case 0x16: // Conflicting industry types
                                for (byte j = 0; j < 3; j++) indsp->conflicting[j] = buf->ReadByte();
                                break;

                        case 0x17: // Probability in random game
                                indsp->appear_creation[_settings_game.game_creation.landscape] = buf->ReadByte();
                                break;

                        case 0x18: // Probability during gameplay
                                indsp->appear_ingame[_settings_game.game_creation.landscape] = buf->ReadByte();
                                break;

                        case 0x19: // Map colour
                                indsp->map_colour = buf->ReadByte();
                                break;

                        case 0x1A: // Special industry flags to define special behavior
                                indsp->behaviour = (IndustryBehaviour)buf->ReadDWord();
                                break;

                        case 0x1B: // New industry text ID
                                AddStringForMapping(buf->ReadWord(), &indsp->new_industry_text);
                                break;

                        case 0x1C: // Input cargo multipliers for the three input cargo types
                        case 0x1D:
                        case 0x1E: {
                                uint32 multiples = buf->ReadDWord();
                                indsp->input_cargo_multiplier[prop - 0x1C][0] = GB(multiples, 0, 16);
                                indsp->input_cargo_multiplier[prop - 0x1C][1] = GB(multiples, 16, 16);
                                break;
                        }

                        case 0x1F: // Industry name
                                AddStringForMapping(buf->ReadWord(), &indsp->name);
                                break;

                        case 0x20: // Prospecting success chance
                                indsp->prospecting_chance = buf->ReadDWord();
                                break;

                        case 0x21:   // Callback mask
                        case 0x22: { // Callback additional mask
                                byte aflag = buf->ReadByte();
                                SB(indsp->callback_mask, (prop - 0x21) * 8, 8, aflag);
                                break;
                        }

                        case 0x23: // removal cost multiplier
                                indsp->removal_cost_multiplier = buf->ReadDWord();
                                break;

                        case 0x24: { // name for nearby station
                                uint16 str = buf->ReadWord();
                                if (str == 0) {
                                        indsp->station_name = STR_NULL;
                                } else {
                                        AddStringForMapping(str, &indsp->station_name);
                                }
                                break;
                        }

                        default:
                                ret = CIR_UNKNOWN;
                                break;
                }
        }

        return ret;
}

/**
 * Create a copy of the tile table so it can be freed later
 * without problems.
 * @param as The AirportSpec to copy the arrays of.
 */
static void DuplicateTileTable(AirportSpec *as)
{
        AirportTileTable **table_list = MallocT<AirportTileTable*>(as->num_table);
        for (int i = 0; i < as->num_table; i++) {
                uint num_tiles = 1;
                const AirportTileTable *it = as->table[0];
                do {
                        num_tiles++;
                } while ((++it)->ti.x != -0x80);
                table_list[i] = MallocT<AirportTileTable>(num_tiles);
                MemCpyT(table_list[i], as->table[i], num_tiles);
        }
        as->table = table_list;
        HangarTileTable *depot_table = nullptr;
        if (as->nof_depots > 0) {
                depot_table = MallocT<HangarTileTable>(as->nof_depots);
                MemCpyT(depot_table, as->depot_table, as->nof_depots);
        }
        as->depot_table = depot_table;
        Direction *rotation = MallocT<Direction>(as->num_table);
        MemCpyT(rotation, as->rotation, as->num_table);
        as->rotation = rotation;
}

/**
 * Define properties for airports
 * @param airport Local ID of the airport.
 * @param numinfo Number of subsequent airport IDs to change the property for.
 * @param prop The property to change.
 * @param buf The property value.
 * @return ChangeInfoResult.
 */
static ChangeInfoResult AirportChangeInfo(uint airport, int numinfo, int prop, ByteReader *buf)
{
        ChangeInfoResult ret = CIR_SUCCESS;

        if (airport + numinfo > NUM_AIRPORTS_PER_GRF) {
                grfmsg(1, "AirportChangeInfo: Too many airports, trying id (%u), max (%u). Ignoring.", airport + numinfo, NUM_AIRPORTS_PER_GRF);
                return CIR_INVALID_ID;
        }

        /* Allocate industry specs if they haven't been allocated already. */
        if (_cur.grffile->airportspec == nullptr) {
                _cur.grffile->airportspec = CallocT<AirportSpec*>(NUM_AIRPORTS_PER_GRF);
        }

        for (int i = 0; i < numinfo; i++) {
                AirportSpec *as = _cur.grffile->airportspec[airport + i];

                if (as == nullptr && prop != 0x08 && prop != 0x09) {
                        grfmsg(2, "AirportChangeInfo: Attempt to modify undefined airport %u, ignoring", airport + i);
                        return CIR_INVALID_ID;
                }

                switch (prop) {
                        case 0x08: { // Modify original airport
                                byte subs_id = buf->ReadByte();

                                if (subs_id == 0xFF) {
                                        /* Instead of defining a new airport, an airport id
                                         * of 0xFF disables the old airport with the current id. */
                                        AirportSpec::GetWithoutOverride(airport + i)->enabled = false;
                                        continue;
                                } else if (subs_id >= NEW_AIRPORT_OFFSET) {
                                        /* The substitute id must be one of the original airports. */
                                        grfmsg(2, "AirportChangeInfo: Attempt to use new airport %u as substitute airport for %u. Ignoring.", subs_id, airport + i);
                                        continue;
                                }

                                AirportSpec **spec = &_cur.grffile->airportspec[airport + i];
                                /* Allocate space for this airport.
                                 * Only need to do it once. If ever it is called again, it should not
                                 * do anything */
                                if (*spec == nullptr) {
                                        *spec = MallocT<AirportSpec>(1);
                                        as = *spec;

                                        memcpy(as, AirportSpec::GetWithoutOverride(subs_id), sizeof(*as));
                                        as->enabled = true;
                                        as->grf_prop.local_id = airport + i;
                                        as->grf_prop.subst_id = subs_id;
                                        as->grf_prop.grffile = _cur.grffile;
                                        /* override the default airport */
                                        _airport_mngr.Add(airport + i, _cur.grffile->grfid, subs_id);
                                        /* Create a copy of the original tiletable so it can be freed later. */
                                        DuplicateTileTable(as);
                                }
                                break;
                        }

                        case 0x0A: { // Set airport layout
                                as->num_table = buf->ReadByte(); // Number of layaouts
                                free(as->rotation);
                                as->rotation = MallocT<Direction>(as->num_table);
                                uint32 defsize = buf->ReadDWord();  // Total size of the definition
                                AirportTileTable **tile_table = CallocT<AirportTileTable*>(as->num_table); // Table with tiles to compose the airport
                                AirportTileTable *att = CallocT<AirportTileTable>(defsize); // Temporary array to read the tile layouts from the GRF
                                int size;
                                const AirportTileTable *copy_from;
                                try {
                                        for (byte j = 0; j < as->num_table; j++) {
                                                const_cast<Direction&>(as->rotation[j]) = (Direction)buf->ReadByte();
                                                for (int k = 0;; k++) {
                                                        att[k].ti.x = buf->ReadByte(); // Offsets from northermost tile
                                                        att[k].ti.y = buf->ReadByte();

                                                        if (att[k].ti.x == 0 && att[k].ti.y == 0x80) {
                                                                /*  Not the same terminator.  The one we are using is rather
                                                                 * x = -80, y = 0 .  So, adjust it. */
                                                                att[k].ti.x = -0x80;
                                                                att[k].ti.y =  0;
                                                                att[k].gfx  =  0;

                                                                size = k + 1;
                                                                copy_from = att;
                                                                break;
                                                        }

                                                        att[k].gfx = buf->ReadByte();

                                                        if (att[k].gfx == 0xFE) {
                                                                /* Use a new tile from this GRF */
                                                                int local_tile_id = buf->ReadWord();

                                                                /* Read the ID from the _airporttile_mngr. */
                                                                uint16 tempid = _airporttile_mngr.GetID(local_tile_id, _cur.grffile->grfid);

                                                                if (tempid == INVALID_AIRPORTTILE) {
                                                                        grfmsg(2, "AirportChangeInfo: Attempt to use airport tile %u with airport id %u, not yet defined. Ignoring.", local_tile_id, airport + i);
                                                                } else {
                                                                        /* Declared as been valid, can be used */
                                                                        att[k].gfx = tempid;
                                                                        size = k + 1;
                                                                        copy_from = att;
                                                                }
                                                        } else if (att[k].gfx == 0xFF) {
                                                                att[k].ti.x = (int8)GB(att[k].ti.x, 0, 8);
                                                                att[k].ti.y = (int8)GB(att[k].ti.y, 0, 8);
                                                        }

                                                        if (as->rotation[j] == DIR_E || as->rotation[j] == DIR_W) {
                                                                as->size_x = max<byte>(as->size_x, att[k].ti.y + 1);
                                                                as->size_y = max<byte>(as->size_y, att[k].ti.x + 1);
                                                        } else {
                                                                as->size_x = max<byte>(as->size_x, att[k].ti.x + 1);
                                                                as->size_y = max<byte>(as->size_y, att[k].ti.y + 1);
                                                        }
                                                }
                                                tile_table[j] = CallocT<AirportTileTable>(size);
                                                memcpy(tile_table[j], copy_from, sizeof(*copy_from) * size);
                                        }
                                        /* Install final layout construction in the airport spec */
                                        as->table = tile_table;
                                        free(att);
                                } catch (...) {
                                        for (int i = 0; i < as->num_table; i++) {
                                                free(tile_table[i]);
                                        }
                                        free(tile_table);
                                        free(att);
                                        throw;
                                }
                                break;
                        }

                        case 0x0C:
                                as->min_year = buf->ReadWord();
                                as->max_year = buf->ReadWord();
                                if (as->max_year == 0xFFFF) as->max_year = MAX_YEAR;
                                break;

                        case 0x0D:
                                as->ttd_airport_type = (TTDPAirportType)buf->ReadByte();
                                break;

                        case 0x0E:
                                as->catchment = Clamp(buf->ReadByte(), 1, MAX_CATCHMENT);
                                break;

                        case 0x0F:
                                as->noise_level = buf->ReadByte();
                                break;

                        case 0x10:
                                AddStringForMapping(buf->ReadWord(), &as->name);
                                break;

                        case 0x11: // Maintenance cost factor
                                as->maintenance_cost = buf->ReadWord();
                                break;
 
                        case 0x12: { // Accept seaplanes
                                byte is_seaplane = buf->ReadByte();
                                if (is_seaplane == 0x01){
                                        as->cls_id = APC_SEA;
                                }
                                break;
                        }

                        default:
                                ret = CIR_UNKNOWN;
                                break;
                }
        }

        return ret;
}

/**
 * Ignore properties for objects
 * @param prop The property to ignore.
 * @param buf The property value.
 * @return ChangeInfoResult.
 */
static ChangeInfoResult IgnoreObjectProperty(uint prop, ByteReader *buf)
{
        ChangeInfoResult ret = CIR_SUCCESS;

        switch (prop) {
                case 0x0B:
                case 0x0C:
                case 0x0D:
                case 0x12:
                case 0x14:
                case 0x16:
                case 0x17:
                        buf->ReadByte();
                        break;

                case 0x09:
                case 0x0A:
                case 0x10:
                case 0x11:
                case 0x13:
                case 0x15:
                        buf->ReadWord();
                        break;

                case 0x08:
                case 0x0E:
                case 0x0F:
                        buf->ReadDWord();
                        break;

                default:
                        ret = CIR_UNKNOWN;
                        break;
        }

        return ret;
}

/**
 * Define properties for objects
 * @param id Local ID of the object.
 * @param numinfo Number of subsequent objectIDs to change the property for.
 * @param prop The property to change.
 * @param buf The property value.
 * @return ChangeInfoResult.
 */
static ChangeInfoResult ObjectChangeInfo(uint id, int numinfo, int prop, ByteReader *buf)
{
        ChangeInfoResult ret = CIR_SUCCESS;

        if (id + numinfo > NUM_OBJECTS_PER_GRF) {
                grfmsg(1, "ObjectChangeInfo: Too many objects loaded (%u), max (%u). Ignoring.", id + numinfo, NUM_OBJECTS_PER_GRF);
                return CIR_INVALID_ID;
        }

        /* Allocate object specs if they haven't been allocated already. */
        if (_cur.grffile->objectspec == nullptr) {
                _cur.grffile->objectspec = CallocT<ObjectSpec*>(NUM_OBJECTS_PER_GRF);
        }

        for (int i = 0; i < numinfo; i++) {
                ObjectSpec *spec = _cur.grffile->objectspec[id + i];

                if (prop != 0x08 && spec == nullptr) {
                        /* If the object property 08 is not yet set, ignore this property */
                        ChangeInfoResult cir = IgnoreObjectProperty(prop, buf);
                        if (cir > ret) ret = cir;
                        continue;
                }

                switch (prop) {
                        case 0x08: { // Class ID
                                ObjectSpec **ospec = &_cur.grffile->objectspec[id + i];

                                /* Allocate space for this object. */
                                if (*ospec == nullptr) {
                                        *ospec = CallocT<ObjectSpec>(1);
                                        (*ospec)->views = 1; // Default for NewGRFs that don't set it.
                                }

                                /* Swap classid because we read it in BE. */
                                uint32 classid = buf->ReadDWord();
                                (*ospec)->cls_id = ObjectClass::Allocate(BSWAP32(classid));
                                (*ospec)->enabled = true;
                                break;
                        }

                        case 0x09: { // Class name
                                ObjectClass *objclass = ObjectClass::Get(spec->cls_id);
                                AddStringForMapping(buf->ReadWord(), &objclass->name);
                                break;
                        }

                        case 0x0A: // Object name
                                AddStringForMapping(buf->ReadWord(), &spec->name);
                                break;

                        case 0x0B: // Climate mask
                                spec->climate = buf->ReadByte();
                                break;

                        case 0x0C: // Size
                                spec->size = buf->ReadByte();
                                break;

                        case 0x0D: // Build cost multipler
                                spec->build_cost_multiplier = buf->ReadByte();
                                spec->clear_cost_multiplier = spec->build_cost_multiplier;
                                break;

                        case 0x0E: // Introduction date
                                spec->introduction_date = buf->ReadDWord();
                                break;

                        case 0x0F: // End of life
                                spec->end_of_life_date = buf->ReadDWord();
                                break;

                        case 0x10: // Flags
                                spec->flags = (ObjectFlags)buf->ReadWord();
                                _loaded_newgrf_features.has_2CC |= (spec->flags & OBJECT_FLAG_2CC_COLOUR) != 0;
                                break;

                        case 0x11: // Animation info
                                spec->animation.frames = buf->ReadByte();
                                spec->animation.status = buf->ReadByte();
                                break;

                        case 0x12: // Animation speed
                                spec->animation.speed = buf->ReadByte();
                                break;

                        case 0x13: // Animation triggers
                                spec->animation.triggers = buf->ReadWord();
                                break;

                        case 0x14: // Removal cost multiplier
                                spec->clear_cost_multiplier = buf->ReadByte();
                                break;

                        case 0x15: // Callback mask
                                spec->callback_mask = buf->ReadWord();
                                break;

                        case 0x16: // Building height
                                spec->height = buf->ReadByte();
                                break;

                        case 0x17: // Views
                                spec->views = buf->ReadByte();
                                if (spec->views != 1 && spec->views != 2 && spec->views != 4) {
                                        grfmsg(2, "ObjectChangeInfo: Invalid number of views (%u) for object id %u. Ignoring.", spec->views, id + i);
                                        spec->views = 1;
                                }
                                break;

                        case 0x18: // Amount placed on 256^2 map on map creation
                                spec->generate_amount = buf->ReadByte();
                                break;

                        default:
                                ret = CIR_UNKNOWN;
                                break;
                }
        }

        return ret;
}

/**
 * Define properties for railtypes
 * @param id ID of the railtype.
 * @param numinfo Number of subsequent IDs to change the property for.
 * @param prop The property to change.
 * @param buf The property value.
 * @return ChangeInfoResult.
 */
static ChangeInfoResult RailTypeChangeInfo(uint id, int numinfo, int prop, ByteReader *buf)
{
        ChangeInfoResult ret = CIR_SUCCESS;

        extern RailtypeInfo _railtypes[RAILTYPE_END];

        if (id + numinfo > RAILTYPE_END) {
                grfmsg(1, "RailTypeChangeInfo: Rail type %u is invalid, max %u, ignoring", id + numinfo, RAILTYPE_END);
                return CIR_INVALID_ID;
        }

        for (int i = 0; i < numinfo; i++) {
                RailType rt = _cur.grffile->railtype_map[id + i];
                if (rt == INVALID_RAILTYPE) return CIR_INVALID_ID;

                RailtypeInfo *rti = &_railtypes[rt];

                switch (prop) {
                        case 0x08: // Label of rail type
                                /* Skipped here as this is loaded during reservation stage. */
                                buf->ReadDWord();
                                break;

                        case 0x09: { // Toolbar caption of railtype (sets name as well for backwards compatibility for grf ver < 8)
                                uint16 str = buf->ReadWord();
                                AddStringForMapping(str, &rti->strings.toolbar_caption);
                                if (_cur.grffile->grf_version < 8) {
                                        AddStringForMapping(str, &rti->strings.name);
                                }
                                break;
                        }

                        case 0x0A: // Menu text of railtype
                                AddStringForMapping(buf->ReadWord(), &rti->strings.menu_text);
                                break;

                        case 0x0B: // Build window caption
                                AddStringForMapping(buf->ReadWord(), &rti->strings.build_caption);
                                break;

                        case 0x0C: // Autoreplace text
                                AddStringForMapping(buf->ReadWord(), &rti->strings.replace_text);
                                break;

                        case 0x0D: // New locomotive text
                                AddStringForMapping(buf->ReadWord(), &rti->strings.new_loco);
                                break;

                        case 0x0E: // Compatible railtype list
                        case 0x0F: // Powered railtype list
                        case 0x18: // Railtype list required for date introduction
                        case 0x19: // Introduced railtype list
                        {
                                /* Rail type compatibility bits are added to the existing bits
                                 * to allow multiple GRFs to modify compatibility with the
                                 * default rail types. */
                                int n = buf->ReadByte();
                                for (int j = 0; j != n; j++) {
                                        RailTypeLabel label = buf->ReadDWord();
                                        RailType rt = GetRailTypeByLabel(BSWAP32(label), false);
                                        if (rt != INVALID_RAILTYPE) {
                                                switch (prop) {
                                                        case 0x0F: SetBit(rti->powered_railtypes, rt);               FALLTHROUGH; // Powered implies compatible.
                                                        case 0x0E: SetBit(rti->compatible_railtypes, rt);            break;
                                                        case 0x18: SetBit(rti->introduction_required_railtypes, rt); break;
                                                        case 0x19: SetBit(rti->introduces_railtypes, rt);            break;
                                                }
                                        }
                                }
                                break;
                        }

                        case 0x10: // Rail Type flags
                                rti->flags = (RailTypeFlags)buf->ReadByte();
                                break;

                        case 0x11: // Curve speed advantage
                                rti->curve_speed = buf->ReadByte();
                                break;

                        case 0x12: // Station graphic
                                rti->fallback_railtype = Clamp(buf->ReadByte(), 0, 2);
                                break;

                        case 0x13: // Construction cost factor
                                rti->cost_multiplier = buf->ReadWord();
                                break;

                        case 0x14: // Speed limit
                                rti->max_speed = buf->ReadWord();
                                break;

                        case 0x15: // Acceleration model
                                rti->acceleration_type = Clamp(buf->ReadByte(), 0, 2);
                                break;

                        case 0x16: // Map colour
                                rti->map_colour = buf->ReadByte();
                                break;

                        case 0x17: // Introduction date
                                rti->introduction_date = buf->ReadDWord();
                                break;

                        case 0x1A: // Sort order
                                rti->sorting_order = buf->ReadByte();
                                break;

                        case 0x1B: // Name of railtype (overridden by prop 09 for grf ver < 8)
                                AddStringForMapping(buf->ReadWord(), &rti->strings.name);
                                break;

                        case 0x1C: // Maintenance cost factor
                                rti->maintenance_multiplier = buf->ReadWord();
                                break;

                        case 0x1D: // Alternate rail type label list
                                /* Skipped here as this is loaded during reservation stage. */
                                for (int j = buf->ReadByte(); j != 0; j--) buf->ReadDWord();
                                break;

                        default:
                                ret = CIR_UNKNOWN;
                                break;
                }
        }

        return ret;
}

static ChangeInfoResult RailTypeReserveInfo(uint id, int numinfo, int prop, ByteReader *buf)
{
        ChangeInfoResult ret = CIR_SUCCESS;

        extern RailtypeInfo _railtypes[RAILTYPE_END];

        if (id + numinfo > RAILTYPE_END) {
                grfmsg(1, "RailTypeReserveInfo: Rail type %u is invalid, max %u, ignoring", id + numinfo, RAILTYPE_END);
                return CIR_INVALID_ID;
        }

        for (int i = 0; i < numinfo; i++) {
                switch (prop) {
                        case 0x08: // Label of rail type
                        {
                                RailTypeLabel rtl = buf->ReadDWord();
                                rtl = BSWAP32(rtl);

                                RailType rt = GetRailTypeByLabel(rtl, false);
                                if (rt == INVALID_RAILTYPE) {
                                        /* Set up new rail type */
                                        rt = AllocateRailType(rtl);
                                }

                                _cur.grffile->railtype_map[id + i] = rt;
                                break;
                        }

                        case 0x09: // Toolbar caption of railtype
                        case 0x0A: // Menu text
                        case 0x0B: // Build window caption
                        case 0x0C: // Autoreplace text
                        case 0x0D: // New loco
                        case 0x13: // Construction cost
                        case 0x14: // Speed limit
                        case 0x1B: // Name of railtype
                        case 0x1C: // Maintenance cost factor
                                buf->ReadWord();
                                break;

                        case 0x1D: // Alternate rail type label list
                                if (_cur.grffile->railtype_map[id + i] != INVALID_RAILTYPE) {
                                        int n = buf->ReadByte();
                                        for (int j = 0; j != n; j++) {
                                                *_railtypes[_cur.grffile->railtype_map[id + i]].alternate_labels.Append() = BSWAP32(buf->ReadDWord());
                                        }
                                        break;
                                }
                                grfmsg(1, "RailTypeReserveInfo: Ignoring property 1D for rail type %u because no label was set", id + i);
                                FALLTHROUGH;

                        case 0x0E: // Compatible railtype list
                        case 0x0F: // Powered railtype list
                        case 0x18: // Railtype list required for date introduction
                        case 0x19: // Introduced railtype list
                                for (int j = buf->ReadByte(); j != 0; j--) buf->ReadDWord();
                                break;

                        case 0x10: // Rail Type flags
                        case 0x11: // Curve speed advantage
                        case 0x12: // Station graphic
                        case 0x15: // Acceleration model
                        case 0x16: // Map colour
                        case 0x1A: // Sort order
                                buf->ReadByte();
                                break;

                        case 0x17: // Introduction date
                                buf->ReadDWord();
                                break;

                        default:
                                ret = CIR_UNKNOWN;
                                break;
                }
        }

        return ret;
}

/**
 * Define properties for roadtypes
 * @param id ID of the roadtype.
 * @param numinfo Number of subsequent IDs to change the property for.
 * @param prop The property to change.
 * @param buf The property value.
 * @return ChangeInfoResult.
 */
static ChangeInfoResult RoadTypeChangeInfo(uint id, int numinfo, int prop, ByteReader *buf, RoadType basetype)
{
        ChangeInfoResult ret = CIR_SUCCESS;

        extern RoadtypeInfo _roadtypes[ROADTYPE_END][ROADSUBTYPE_END];

        if (basetype > ROADTYPE_END) {
                grfmsg(1, "RoadTypeChangeInfo: Road type %u is invalid, max %u, ignoring", basetype, ROADTYPE_END);
                return CIR_INVALID_ID;
        }

        if (id + numinfo > ROADSUBTYPE_END) {
                grfmsg(1, "RoadTypeChangeInfo: Road type %u is invalid, max %u, ignoring", id + numinfo, ROADSUBTYPE_END);
                return CIR_INVALID_ID;
        }

        for (int i = 0; i < numinfo; i++) {
                RoadTypeIdentifier rtid = RoadTypeIdentifier(basetype, (RoadSubType)_cur.grffile->roadtype_map[basetype][id + i]);
                if (!rtid.IsValid()) return CIR_INVALID_ID;

                RoadtypeInfo *rti = &_roadtypes[basetype][rtid.subtype];

                switch (prop) {
                        case 0x08: // Label of road type
                                /* Skipped here as this is loaded during reservation stage. */
                                buf->ReadDWord();
                                break;

                        case 0x09: { // Toolbar caption of roadtype (sets name as well for backwards compatibility for grf ver < 8)
                                uint16 str = buf->ReadWord();
                                AddStringForMapping(str, &rti->strings.toolbar_caption);
                                break;
                        }

                        case 0x0A: // Menu text of roadtype
                                AddStringForMapping(buf->ReadWord(), &rti->strings.menu_text);
                                break;

                        case 0x0B: // Build window caption
                                AddStringForMapping(buf->ReadWord(), &rti->strings.build_caption);
                                break;

                        case 0x0C: // Autoreplace text
                                AddStringForMapping(buf->ReadWord(), &rti->strings.replace_text);
                                break;

                        case 0x0D: // New engine text
                                AddStringForMapping(buf->ReadWord(), &rti->strings.new_engine);
                                break;

                        case 0x0F: // Powered roadtype list
                        case 0x18: // Roadtype list required for date introduction
                        case 0x19: { // Introduced roadtype list
                                /* Road type compatibility bits are added to the existing bits
                                 * to allow multiple GRFs to modify compatibility with the
                                 * default road types. */
                                int n = buf->ReadByte();
                                for (int j = 0; j != n; j++) {
                                        RoadTypeLabel label = buf->ReadDWord();
                                        RoadTypeIdentifier c_rtid = GetRoadTypeByLabel(BSWAP32(label), basetype, false);
                                        if (c_rtid.IsValid()) {
                                                switch (prop) {
                                                        case 0x0F: SetBit(rti->powered_roadtypes, c_rtid.subtype);               break;
                                                        case 0x18: SetBit(rti->introduction_required_roadtypes, c_rtid.subtype); break;
                                                        case 0x19: SetBit(rti->introduces_roadtypes, c_rtid.subtype);            break;
                                                }
                                        }
                                }
                                break;
                        }

                        case 0x10: // Road Type flags
                                rti->flags = (RoadTypeFlags)buf->ReadByte();
                                break;

                        case 0x13: // Construction cost factor
                                rti->cost_multiplier = buf->ReadWord();
                                break;

                        case 0x14: // Speed limit
                                rti->max_speed = buf->ReadWord();
                                break;

                        case 0x16: // Map colour
                                rti->map_colour = buf->ReadByte();
                                break;

                        case 0x17: // Introduction date
                                rti->introduction_date = buf->ReadDWord();
                                break;

                        case 0x1A: // Sort order
                                rti->sorting_order = buf->ReadByte();
                                break;

                        case 0x1B: // Name of roadtype
                                AddStringForMapping(buf->ReadWord(), &rti->strings.name);
                                break;

                        case 0x1C: // Maintenance cost factor
                                rti->maintenance_multiplier = buf->ReadWord();
                                break;

                        case 0x1D: // Alternate road type label list
                                /* Skipped here as this is loaded during reservation stage. */
                                for (int j = buf->ReadByte(); j != 0; j--) buf->ReadDWord();
                                break;

                        default:
                                ret = CIR_UNKNOWN;
                                break;
                }
        }

        return ret;
}

static ChangeInfoResult RoadTypeChangeInfo(uint id, int numinfo, int prop, ByteReader *buf)
{
        return RoadTypeChangeInfo(id, numinfo, prop, buf, ROADTYPE_ROAD);
}

static ChangeInfoResult TramTypeChangeInfo(uint id, int numinfo, int prop, ByteReader *buf)
{
        return RoadTypeChangeInfo(id, numinfo, prop, buf, ROADTYPE_TRAM);
}


static ChangeInfoResult RoadTypeReserveInfo(uint id, int numinfo, int prop, ByteReader *buf, RoadType basetype)
{
        ChangeInfoResult ret = CIR_SUCCESS;

        extern RoadtypeInfo _roadtypes[ROADTYPE_END][ROADSUBTYPE_END];

        if (basetype > ROADTYPE_END) {
                grfmsg(1, "RoadTypeReserveInfo: Road type %u is invalid, max %u, ignoring", basetype, ROADTYPE_END);
                return CIR_INVALID_ID;
        }

        if (id + numinfo > ROADSUBTYPE_END) {
                grfmsg(1, "RoadTypeReserveInfo: Road sub type %u is invalid, max %u, ignoring", id + numinfo, ROADSUBTYPE_END);
                return CIR_INVALID_ID;
        }

        for (int i = 0; i < numinfo; i++) {
                switch (prop) {
                        case 0x08: { // Label of road type
                                RoadTypeLabel rtl = buf->ReadDWord();
                                rtl = BSWAP32(rtl);

                                RoadTypeIdentifier rtid = GetRoadTypeByLabel(rtl, basetype, false);
                                if (!rtid.IsValid()) {
                                        /* Set up new road type */
                                        rtid = AllocateRoadType(rtl, basetype);
                                }

                                _cur.grffile->roadtype_map[basetype][id + i] = rtid.subtype;
                                break;
                        }
                        case 0x09: // Toolbar caption of roadtype
                        case 0x0A: // Menu text
                        case 0x0B: // Build window caption
                        case 0x0C: // Autoreplace text
                        case 0x0D: // New loco
                        case 0x13: // Construction cost
                        case 0x14: // Speed limit
                        case 0x1B: // Name of roadtype
                        case 0x1C: // Maintenance cost factor
                                buf->ReadWord();
                                break;

                        case 0x1D: // Alternate road type label list
                                if (_cur.grffile->roadtype_map[basetype][id + i] != INVALID_ROADSUBTYPE) {
                                        int n = buf->ReadByte();
                                        for (int j = 0; j != n; j++) {
                                                *_roadtypes[basetype][_cur.grffile->roadtype_map[basetype][id + i]].alternate_labels.Append() = BSWAP32(buf->ReadDWord());
                                        }
                                        break;
                                }
                                grfmsg(1, "RoadTypeReserveInfo: Ignoring property 1D for road type %u because no label was set", id + i);
                                /* FALL THROUGH */

                        case 0x0F: // Powered roadtype list
                        case 0x18: // Roadtype list required for date introduction
                        case 0x19: // Introduced roadtype list
                                for (int j = buf->ReadByte(); j != 0; j--) buf->ReadDWord();
                                break;

                        case 0x10: // Road Type flags
                        case 0x12: // Station graphic
                        case 0x15: // Acceleration model
                        case 0x16: // Map colour
                        case 0x1A: // Sort order
                                buf->ReadByte();
                                break;

                        case 0x17: // Introduction date
                                buf->ReadDWord();
                                break;

                        default:
                                ret = CIR_UNKNOWN;
                                break;
                }
        }

        return ret;
}

static ChangeInfoResult RoadTypeReserveInfo(uint id, int numinfo, int prop, ByteReader *buf)
{
        return RoadTypeReserveInfo(id, numinfo, prop, buf, ROADTYPE_ROAD);
}

static ChangeInfoResult TramTypeReserveInfo(uint id, int numinfo, int prop, ByteReader *buf)
{
        return RoadTypeReserveInfo(id, numinfo, prop, buf, ROADTYPE_TRAM);
}

static ChangeInfoResult AirportTilesChangeInfo(uint airtid, int numinfo, int prop, ByteReader *buf)
{
        ChangeInfoResult ret = CIR_SUCCESS;

        if (airtid + numinfo > NUM_AIRPORTTILES_PER_GRF) {
                grfmsg(1, "AirportTileChangeInfo: Too many airport tiles loaded (%u), max (%u). Ignoring.", airtid + numinfo, NUM_AIRPORTTILES_PER_GRF);
                return CIR_INVALID_ID;
        }

        /* Allocate airport tile specs if they haven't been allocated already. */
        if (_cur.grffile->airtspec == nullptr) {
                _cur.grffile->airtspec = CallocT<AirportTileSpec*>(NUM_AIRPORTTILES_PER_GRF);
        }

        for (int i = 0; i < numinfo; i++) {
                AirportTileSpec *tsp = _cur.grffile->airtspec[airtid + i];

                if (prop != 0x08 && tsp == nullptr) {
                        grfmsg(2, "AirportTileChangeInfo: Attempt to modify undefined airport tile %u. Ignoring.", airtid + i);
                        return CIR_INVALID_ID;
                }

                switch (prop) {
                        case 0x08: { // Substitute airport tile type
                                AirportTileSpec **tilespec = &_cur.grffile->airtspec[airtid + i];
                                byte subs_id = buf->ReadByte();

                                if (subs_id >= NEW_AIRPORTTILE_OFFSET) {
                                        /* The substitute id must be one of the original airport tiles. */
                                        grfmsg(2, "AirportTileChangeInfo: Attempt to use new airport tile %u as substitute airport tile for %u. Ignoring.", subs_id, airtid + i);
                                        continue;
                                }

                                /* Allocate space for this airport tile. */
                                if (*tilespec == nullptr) {
                                        *tilespec = CallocT<AirportTileSpec>(1);
                                        tsp = *tilespec;

                                        memcpy(tsp, AirportTileSpec::Get(subs_id), sizeof(AirportTileSpec));
                                        tsp->enabled = true;

                                        tsp->animation.status = ANIM_STATUS_NO_ANIMATION;

                                        tsp->grf_prop.local_id = airtid + i;
                                        tsp->grf_prop.subst_id = subs_id;
                                        tsp->grf_prop.grffile = _cur.grffile;
                                        _airporttile_mngr.AddEntityID(airtid + i, _cur.grffile->grfid, subs_id); // pre-reserve the tile slot
                                }
                                break;
                        }

                        case 0x09: { // Airport tile override
                                byte override = buf->ReadByte();

                                /* The airport tile being overridden must be an original airport tile. */
                                if (override >= NEW_AIRPORTTILE_OFFSET) {
                                        grfmsg(2, "AirportTileChangeInfo: Attempt to override new airport tile %u with airport tile id %u. Ignoring.", override, airtid + i);
                                        continue;
                                }

                                _airporttile_mngr.Add(airtid + i, _cur.grffile->grfid, override);
                                break;
                        }

                        case 0x0E: // Callback mask
                                tsp->callback_mask = buf->ReadByte();
                                break;

                        case 0x0F: // Animation information
                                tsp->animation.frames = buf->ReadByte();
                                tsp->animation.status = buf->ReadByte();
                                break;

                        case 0x10: // Animation speed
                                tsp->animation.speed = buf->ReadByte();
                                break;

                        case 0x11: // Animation triggers
                                tsp->animation.triggers = buf->ReadByte();
                                break;

                        default:
                                ret = CIR_UNKNOWN;
                                break;
                }
        }

        return ret;
}

static bool HandleChangeInfoResult(const char *caller, ChangeInfoResult cir, uint8 feature, uint8 property)
{
        switch (cir) {
                default: NOT_REACHED();

                case CIR_DISABLED:
                        /* Error has already been printed; just stop parsing */
                        return true;

                case CIR_SUCCESS:
                        return false;

                case CIR_UNHANDLED:
                        grfmsg(1, "%s: Ignoring property 0x%02X of feature 0x%02X (not implemented)", caller, property, feature);
                        return false;

                case CIR_UNKNOWN:
                        grfmsg(0, "%s: Unknown property 0x%02X of feature 0x%02X, disabling", caller, property, feature);
                        FALLTHROUGH;

                case CIR_INVALID_ID: {
                        /* No debug message for an invalid ID, as it has already been output */
                        GRFError *error = DisableGrf(cir == CIR_INVALID_ID ? STR_NEWGRF_ERROR_INVALID_ID : STR_NEWGRF_ERROR_UNKNOWN_PROPERTY);
                        if (cir != CIR_INVALID_ID) error->param_value[1] = property;
                        return true;
                }
        }
}

/* Action 0x00 */
static void FeatureChangeInfo(ByteReader *buf)
{
        /* <00> <feature> <num-props> <num-info> <id> (<property <new-info>)...
         *
         * B feature
         * B num-props     how many properties to change per vehicle/station
         * B num-info      how many vehicles/stations to change
         * E id            ID of first vehicle/station to change, if num-info is
         *                 greater than one, this one and the following
         *                 vehicles/stations will be changed
         * B property      what property to change, depends on the feature
         * V new-info      new bytes of info (variable size; depends on properties) */

        static const VCI_Handler handler[] = {
                /* GSF_TRAINS */        RailVehicleChangeInfo,
                /* GSF_ROADVEHICLES */  RoadVehicleChangeInfo,
                /* GSF_SHIPS */         ShipVehicleChangeInfo,
                /* GSF_AIRCRAFT */      AircraftVehicleChangeInfo,
                /* GSF_STATIONS */      StationChangeInfo,
                /* GSF_CANALS */        CanalChangeInfo,
                /* GSF_BRIDGES */       BridgeChangeInfo,
                /* GSF_HOUSES */        TownHouseChangeInfo,
                /* GSF_GLOBALVAR */     GlobalVarChangeInfo,
                /* GSF_INDUSTRYTILES */ IndustrytilesChangeInfo,
                /* GSF_INDUSTRIES */    IndustriesChangeInfo,
                /* GSF_CARGOES */       nullptr, // Cargo is handled during reservation
                /* GSF_SOUNDFX */       SoundEffectChangeInfo,
                /* GSF_AIRPORTS */      AirportChangeInfo,
                /* GSF_SIGNALS */       nullptr,
                /* GSF_OBJECTS */       ObjectChangeInfo,
                /* GSF_RAILTYPES */     RailTypeChangeInfo,
                /* GSF_AIRPORTTILES */  AirportTilesChangeInfo,
                /* GSF_ROADTYPES */     RoadTypeChangeInfo,
                /* GSF_TRAMTYPES */     TramTypeChangeInfo,
        };

        uint8 feature  = buf->ReadByte();
        uint8 numprops = buf->ReadByte();
        uint numinfo  = buf->ReadByte();
        uint engine   = buf->ReadExtendedByte();

        grfmsg(6, "FeatureChangeInfo: feature %d, %d properties, to apply to %d+%d",
                                   feature, numprops, engine, numinfo);

        if (feature >= lengthof(handler) || handler[feature] == nullptr) {
                if (feature != GSF_CARGOES) grfmsg(1, "FeatureChangeInfo: Unsupported feature %d, skipping", feature);
                return;
        }

        /* Mark the feature as used by the grf */
        SetBit(_cur.grffile->grf_features, feature);

        while (numprops-- && buf->HasData()) {
                uint8 prop = buf->ReadByte();

                ChangeInfoResult cir = handler[feature](engine, numinfo, prop, buf);
                if (HandleChangeInfoResult("FeatureChangeInfo", cir, feature, prop)) return;
        }
}

/* Action 0x00 (GLS_SAFETYSCAN) */
static void SafeChangeInfo(ByteReader *buf)
{
        uint8 feature  = buf->ReadByte();
        uint8 numprops = buf->ReadByte();
        uint numinfo = buf->ReadByte();
        buf->ReadExtendedByte(); // id

        if (feature == GSF_BRIDGES && numprops == 1) {
                uint8 prop = buf->ReadByte();
                /* Bridge property 0x0D is redefinition of sprite layout tables, which
                 * is considered safe. */
                if (prop == 0x0D) return;
        } else if (feature == GSF_GLOBALVAR && numprops == 1) {
                uint8 prop = buf->ReadByte();
                /* Engine ID Mappings are safe, if the source is static */
                if (prop == 0x11) {
                        bool is_safe = true;
                        for (uint i = 0; i < numinfo; i++) {
                                uint32 s = buf->ReadDWord();
                                buf->ReadDWord(); // dest
                                const GRFConfig *grfconfig = GetGRFConfig(s);
                                if (grfconfig != nullptr && !HasBit(grfconfig->flags, GCF_STATIC)) {
                                        is_safe = false;
                                        break;
                                }
                        }
                        if (is_safe) return;
                }
        }

        SetBit(_cur.grfconfig->flags, GCF_UNSAFE);

        /* Skip remainder of GRF */
        _cur.skip_sprites = -1;
}

/* Action 0x00 (GLS_RESERVE) */
static void ReserveChangeInfo(ByteReader *buf)
{
        uint8 feature  = buf->ReadByte();

        if (feature != GSF_CARGOES && feature != GSF_GLOBALVAR && feature != GSF_RAILTYPES && feature != GSF_ROADTYPES && feature != GSF_TRAMTYPES) return;

        uint8 numprops = buf->ReadByte();
        uint8 numinfo  = buf->ReadByte();
        uint8 index    = buf->ReadExtendedByte();

        while (numprops-- && buf->HasData()) {
                uint8 prop = buf->ReadByte();
                ChangeInfoResult cir = CIR_SUCCESS;

                switch (feature) {
                        default: NOT_REACHED();
                        case GSF_CARGOES:
                                cir = CargoChangeInfo(index, numinfo, prop, buf);
                                break;

                        case GSF_GLOBALVAR:
                                cir = GlobalVarReserveInfo(index, numinfo, prop, buf);
                                break;

                        case GSF_RAILTYPES:
                                cir = RailTypeReserveInfo(index, numinfo, prop, buf);
                                break;

                        case GSF_ROADTYPES:
                                cir = RoadTypeReserveInfo(index, numinfo, prop, buf);
                                break;

                        case GSF_TRAMTYPES:
                                cir = TramTypeReserveInfo(index, numinfo, prop, buf);
                                break;
                }

                if (HandleChangeInfoResult("ReserveChangeInfo", cir, feature, prop)) return;
        }
}

/* Action 0x01 */
static void NewSpriteSet(ByteReader *buf)
{
        /* Basic format:    <01> <feature> <num-sets> <num-ent>
         * Extended format: <01> <feature> 00 <first-set> <num-sets> <num-ent>
         *
         * B feature       feature to define sprites for
         *                 0, 1, 2, 3: veh-type, 4: train stations
         * E first-set     first sprite set to define
         * B num-sets      number of sprite sets (extended byte in extended format)
         * E num-ent       how many entries per sprite set
         *                 For vehicles, this is the number of different
         *                         vehicle directions in each sprite set
         *                         Set num-dirs=8, unless your sprites are symmetric.
         *                         In that case, use num-dirs=4.
         */

        uint8  feature   = buf->ReadByte();
        uint16 num_sets  = buf->ReadByte();
        uint16 first_set = 0;

        if (num_sets == 0 && buf->HasData(3)) {
                /* Extended Action1 format.
                 * Some GRFs define zero sets of zero sprites, though there is actually no use in that. Ignore them. */
                first_set = buf->ReadExtendedByte();
                num_sets = buf->ReadExtendedByte();
        }
        uint16 num_ents = buf->ReadExtendedByte();

        _cur.AddSpriteSets(feature, _cur.spriteid, first_set, num_sets, num_ents);

        grfmsg(7, "New sprite set at %d of type %d, consisting of %d sets with %d views each (total %d)",
                _cur.spriteid, feature, num_sets, num_ents, num_sets * num_ents
        );

        for (int i = 0; i < num_sets * num_ents; i++) {
                _cur.nfo_line++;
                LoadNextSprite(_cur.spriteid++, _cur.file_index, _cur.nfo_line, _cur.grf_container_ver);
        }
}

/* Action 0x01 (SKIP) */
static void SkipAct1(ByteReader *buf)
{
        buf->ReadByte();
        uint16 num_sets  = buf->ReadByte();

        if (num_sets == 0 && buf->HasData(3)) {
                /* Extended Action1 format.
                 * Some GRFs define zero sets of zero sprites, though there is actually no use in that. Ignore them. */
                buf->ReadExtendedByte(); // first_set
                num_sets = buf->ReadExtendedByte();
        }
        uint16 num_ents = buf->ReadExtendedByte();

        _cur.skip_sprites = num_sets * num_ents;

        grfmsg(3, "SkipAct1: Skipping %d sprites", _cur.skip_sprites);
}

/* Helper function to either create a callback or link to a previously
 * defined spritegroup. */
static const SpriteGroup *GetGroupFromGroupID(byte setid, byte type, uint16 groupid)
{
        if (HasBit(groupid, 15)) {
                assert(CallbackResultSpriteGroup::CanAllocateItem());
                return new CallbackResultSpriteGroup(groupid, _cur.grffile->grf_version >= 8);
        }

        if (groupid > MAX_SPRITEGROUP || _cur.spritegroups[groupid] == nullptr) {
                grfmsg(1, "GetGroupFromGroupID(0x%02X:0x%02X): Groupid 0x%04X does not exist, leaving empty", setid, type, groupid);
                return nullptr;
        }

        return _cur.spritegroups[groupid];
}

/**
 * Helper function to either create a callback or a result sprite group.
 * @param feature GrfSpecFeature to define spritegroup for.
 * @param setid SetID of the currently being parsed Action2. (only for debug output)
 * @param type Type of the currently being parsed Action2. (only for debug output)
 * @param spriteid Raw value from the GRF for the new spritegroup; describes either the return value or the referenced spritegroup.
 * @return Created spritegroup.
 */
static const SpriteGroup *CreateGroupFromGroupID(byte feature, byte setid, byte type, uint16 spriteid)
{
        if (HasBit(spriteid, 15)) {
                assert(CallbackResultSpriteGroup::CanAllocateItem());
                return new CallbackResultSpriteGroup(spriteid, _cur.grffile->grf_version >= 8);
        }

        if (!_cur.IsValidSpriteSet(feature, spriteid)) {
                grfmsg(1, "CreateGroupFromGroupID(0x%02X:0x%02X): Sprite set %u invalid", setid, type, spriteid);
                return nullptr;
        }

        SpriteID spriteset_start = _cur.GetSprite(feature, spriteid);
        uint num_sprites = _cur.GetNumEnts(feature, spriteid);

        /* Ensure that the sprites are loeded */
        assert(spriteset_start + num_sprites <= _cur.spriteid);

        assert(ResultSpriteGroup::CanAllocateItem());
        return new ResultSpriteGroup(spriteset_start, num_sprites);
}

/* Action 0x02 */
static void NewSpriteGroup(ByteReader *buf)
{
        /* <02> <feature> <set-id> <type/num-entries> <feature-specific-data...>
         *
         * B feature       see action 1
         * B set-id        ID of this particular definition
         * B type/num-entries
         *                 if 80 or greater, this is a randomized or variational
         *                 list definition, see below
         *                 otherwise it specifies a number of entries, the exact
         *                 meaning depends on the feature
         * V feature-specific-data (huge mess, don't even look it up --pasky) */
        SpriteGroup *act_group = nullptr;

        uint8 feature = buf->ReadByte();
        uint8 setid   = buf->ReadByte();
        uint8 type    = buf->ReadByte();

        /* Sprite Groups are created here but they are allocated from a pool, so
         * we do not need to delete anything if there is an exception from the
         * ByteReader. */

        switch (type) {
                /* Deterministic Sprite Group */
                case 0x81: // Self scope, byte
                case 0x82: // Parent scope, byte
                case 0x85: // Self scope, word
                case 0x86: // Parent scope, word
                case 0x89: // Self scope, dword
                case 0x8A: // Parent scope, dword
                {
                        byte varadjust;
                        byte varsize;

                        assert(DeterministicSpriteGroup::CanAllocateItem());
                        DeterministicSpriteGroup *group = new DeterministicSpriteGroup();
                        act_group = group;
                        group->var_scope = HasBit(type, 1) ? VSG_SCOPE_PARENT : VSG_SCOPE_SELF;

                        switch (GB(type, 2, 2)) {
                                default: NOT_REACHED();
                                case 0: group->size = DSG_SIZE_BYTE;  varsize = 1; break;
                                case 1: group->size = DSG_SIZE_WORD;  varsize = 2; break;
                                case 2: group->size = DSG_SIZE_DWORD; varsize = 4; break;
                        }

                        static SmallVector<DeterministicSpriteGroupAdjust, 16> adjusts;
                        adjusts.Clear();

                        /* Loop through the var adjusts. Unfortunately we don't know how many we have
                         * from the outset, so we shall have to keep reallocing. */
                        do {
                                DeterministicSpriteGroupAdjust *adjust = adjusts.Append();

                                /* The first var adjust doesn't have an operation specified, so we set it to add. */
                                adjust->operation = adjusts.Length() == 1 ? DSGA_OP_ADD : (DeterministicSpriteGroupAdjustOperation)buf->ReadByte();
                                adjust->variable  = buf->ReadByte();
                                if (adjust->variable == 0x7E) {
                                        /* Link subroutine group */
                                        adjust->subroutine = GetGroupFromGroupID(setid, type, buf->ReadByte());
                                } else {
                                        adjust->parameter = IsInsideMM(adjust->variable, 0x60, 0x80) ? buf->ReadByte() : 0;
                                }

                                varadjust = buf->ReadByte();
                                adjust->shift_num = GB(varadjust, 0, 5);
                                adjust->type      = (DeterministicSpriteGroupAdjustType)GB(varadjust, 6, 2);
                                adjust->and_mask  = buf->ReadVarSize(varsize);

                                if (adjust->type != DSGA_TYPE_NONE) {
                                        adjust->add_val    = buf->ReadVarSize(varsize);
                                        adjust->divmod_val = buf->ReadVarSize(varsize);
                                } else {
                                        adjust->add_val    = 0;
                                        adjust->divmod_val = 0;
                                }

                                /* Continue reading var adjusts while bit 5 is set. */
                        } while (HasBit(varadjust, 5));

                        group->num_adjusts = adjusts.Length();
                        group->adjusts = MallocT<DeterministicSpriteGroupAdjust>(group->num_adjusts);
                        MemCpyT(group->adjusts, adjusts.Begin(), group->num_adjusts);

                        std::vector<DeterministicSpriteGroupRange> ranges;
                        ranges.resize(buf->ReadByte());
                        for (uint i = 0; i < ranges.size(); i++) {
                                ranges[i].group = GetGroupFromGroupID(setid, type, buf->ReadWord());
                                ranges[i].low   = buf->ReadVarSize(varsize);
                                ranges[i].high  = buf->ReadVarSize(varsize);
                        }

                        group->default_group = GetGroupFromGroupID(setid, type, buf->ReadWord());
                        group->error_group = ranges.size() > 0 ? ranges[0].group : group->default_group;
                        /* nvar == 0 is a special case -- we turn our value into a callback result */
                        group->calculated_result = ranges.size() == 0;

                        /* Sort ranges ascending. When ranges overlap, this may required clamping or splitting them */
                        std::vector<uint32> bounds;
                        for (uint i = 0; i < ranges.size(); i++) {
                                bounds.push_back(ranges[i].low);
                                if (ranges[i].high != UINT32_MAX) bounds.push_back(ranges[i].high + 1);
                        }
                        std::sort(bounds.begin(), bounds.end());
                        bounds.erase(std::unique(bounds.begin(), bounds.end()), bounds.end());

                        std::vector<const SpriteGroup *> target;
                        for (uint j = 0; j < bounds.size(); ++j) {
                                uint32 v = bounds[j];
                                const SpriteGroup *t = group->default_group;
                                for (uint i = 0; i < ranges.size(); i++) {
                                        if (ranges[i].low <= v && v <= ranges[i].high) {
                                                t = ranges[i].group;
                                                break;
                                        }
                                }
                                target.push_back(t);
                        }
                        assert(target.size() == bounds.size());

                        std::vector<DeterministicSpriteGroupRange> optimised;
                        for (uint j = 0; j < bounds.size(); ) {
                                if (target[j] != group->default_group) {
                                        DeterministicSpriteGroupRange r;
                                        r.group = target[j];
                                        r.low = bounds[j];
                                        while (j < bounds.size() && target[j] == r.group) {
                                                j++;
                                        }
                                        r.high = j < bounds.size() ? bounds[j] - 1 : UINT32_MAX;
                                        optimised.push_back(r);
                                } else {
                                        j++;
                                }
                        }

                        group->num_ranges = (uint)optimised.size();
                        if (group->num_ranges > 0) {
                                group->ranges = MallocT<DeterministicSpriteGroupRange>(group->num_ranges);
                                MemCpyT(group->ranges, &optimised.front(), group->num_ranges);
                        }
                        break;
                }

                /* Randomized Sprite Group */
                case 0x80: // Self scope
                case 0x83: // Parent scope
                case 0x84: // Relative scope
                {
                        assert(RandomizedSpriteGroup::CanAllocateItem());
                        RandomizedSpriteGroup *group = new RandomizedSpriteGroup();
                        act_group = group;
                        group->var_scope = HasBit(type, 1) ? VSG_SCOPE_PARENT : VSG_SCOPE_SELF;

                        if (HasBit(type, 2)) {
                                if (feature <= GSF_AIRCRAFT) group->var_scope = VSG_SCOPE_RELATIVE;
                                group->count = buf->ReadByte();
                        }

                        uint8 triggers = buf->ReadByte();
                        group->triggers       = GB(triggers, 0, 7);
                        group->cmp_mode       = HasBit(triggers, 7) ? RSG_CMP_ALL : RSG_CMP_ANY;
                        group->lowest_randbit = buf->ReadByte();
                        group->num_groups     = buf->ReadByte();
                        group->groups = CallocT<const SpriteGroup*>(group->num_groups);

                        for (uint i = 0; i < group->num_groups; i++) {
                                group->groups[i] = GetGroupFromGroupID(setid, type, buf->ReadWord());
                        }

                        break;
                }

                /* Neither a variable or randomized sprite group... must be a real group */
                default:
                {
                        switch (feature) {
                                case GSF_TRAINS:
                                case GSF_ROADVEHICLES:
                                case GSF_SHIPS:
                                case GSF_AIRCRAFT:
                                case GSF_STATIONS:
                                case GSF_CANALS:
                                case GSF_CARGOES:
                                case GSF_AIRPORTS:
                                case GSF_RAILTYPES:
                                case GSF_ROADTYPES:
                                case GSF_TRAMTYPES:
                                {
                                        byte num_loaded  = type;
                                        byte num_loading = buf->ReadByte();

                                        if (!_cur.HasValidSpriteSets(feature)) {
                                                grfmsg(0, "NewSpriteGroup: No sprite set to work on! Skipping");
                                                return;
                                        }

                                        assert(RealSpriteGroup::CanAllocateItem());
                                        RealSpriteGroup *group = new RealSpriteGroup();
                                        act_group = group;

                                        group->num_loaded  = num_loaded;
                                        group->num_loading = num_loading;
                                        if (num_loaded  > 0) group->loaded = CallocT<const SpriteGroup*>(num_loaded);
                                        if (num_loading > 0) group->loading = CallocT<const SpriteGroup*>(num_loading);

                                        grfmsg(6, "NewSpriteGroup: New SpriteGroup 0x%02X, %u loaded, %u loading",
                                                        setid, num_loaded, num_loading);

                                        for (uint i = 0; i < num_loaded; i++) {
                                                uint16 spriteid = buf->ReadWord();
                                                group->loaded[i] = CreateGroupFromGroupID(feature, setid, type, spriteid);
                                                grfmsg(8, "NewSpriteGroup: + rg->loaded[%i]  = subset %u", i, spriteid);
                                        }

                                        for (uint i = 0; i < num_loading; i++) {
                                                uint16 spriteid = buf->ReadWord();
                                                group->loading[i] = CreateGroupFromGroupID(feature, setid, type, spriteid);
                                                grfmsg(8, "NewSpriteGroup: + rg->loading[%i] = subset %u", i, spriteid);
                                        }

                                        break;
                                }

                                case GSF_HOUSES:
                                case GSF_AIRPORTTILES:
                                case GSF_OBJECTS:
                                case GSF_INDUSTRYTILES: {
                                        byte num_building_sprites = max((uint8)1, type);

                                        assert(TileLayoutSpriteGroup::CanAllocateItem());
                                        TileLayoutSpriteGroup *group = new TileLayoutSpriteGroup();
                                        act_group = group;

                                        /* On error, bail out immediately. Temporary GRF data was already freed */
                                        if (ReadSpriteLayout(buf, num_building_sprites, true, feature, false, type == 0, &group->dts)) return;
                                        break;
                                }

                                case GSF_INDUSTRIES: {
                                        if (type > 1) {
                                                grfmsg(1, "NewSpriteGroup: Unsupported industry production version %d, skipping", type);
                                                break;
                                        }

                                        assert(IndustryProductionSpriteGroup::CanAllocateItem());
                                        IndustryProductionSpriteGroup *group = new IndustryProductionSpriteGroup();
                                        act_group = group;
                                        group->version = type;
                                        if (type == 0) {
                                                for (uint i = 0; i < 3; i++) {
                                                        group->subtract_input[i] = (int16)buf->ReadWord(); // signed
                                                }
                                                for (uint i = 0; i < 2; i++) {
                                                        group->add_output[i] = buf->ReadWord(); // unsigned
                                                }
                                                group->again = buf->ReadByte();
                                        } else {
                                                for (uint i = 0; i < 3; i++) {
                                                        group->subtract_input[i] = buf->ReadByte();
                                                }
                                                for (uint i = 0; i < 2; i++) {
                                                        group->add_output[i] = buf->ReadByte();
                                                }
                                                group->again = buf->ReadByte();
                                        }
                                        break;
                                }

                                /* Loading of Tile Layout and Production Callback groups would happen here */
                                default: grfmsg(1, "NewSpriteGroup: Unsupported feature %d, skipping", feature);
                        }
                }
        }

        _cur.spritegroups[setid] = act_group;
}

static CargoID TranslateCargo(uint8 feature, uint8 ctype)
{
        if (feature == GSF_OBJECTS) {
                switch (ctype) {
                        case 0:    return 0;
                        case 0xFF: return CT_PURCHASE_OBJECT;
                        default:
                                grfmsg(1, "TranslateCargo: Invalid cargo bitnum %d for objects, skipping.", ctype);
                                return CT_INVALID;
                }
        }
        /* Special cargo types for purchase list and stations */
        if (feature == GSF_STATIONS && ctype == 0xFE) return CT_DEFAULT_NA;
        if (ctype == 0xFF) return CT_PURCHASE;

        if (_cur.grffile->cargo_list.Length() == 0) {
                /* No cargo table, so use bitnum values */
                if (ctype >= 32) {
                        grfmsg(1, "TranslateCargo: Cargo bitnum %d out of range (max 31), skipping.", ctype);
                        return CT_INVALID;
                }

                const CargoSpec *cs;
                FOR_ALL_CARGOSPECS(cs) {
                        if (cs->bitnum == ctype) {
                                grfmsg(6, "TranslateCargo: Cargo bitnum %d mapped to cargo type %d.", ctype, cs->Index());
                                return cs->Index();
                        }
                }

                grfmsg(5, "TranslateCargo: Cargo bitnum %d not available in this climate, skipping.", ctype);
                return CT_INVALID;
        }

        /* Check if the cargo type is out of bounds of the cargo translation table */
        if (ctype >= _cur.grffile->cargo_list.Length()) {
                grfmsg(1, "TranslateCargo: Cargo type %d out of range (max %d), skipping.", ctype, _cur.grffile->cargo_list.Length() - 1);
                return CT_INVALID;
        }

        /* Look up the cargo label from the translation table */
        CargoLabel cl = _cur.grffile->cargo_list[ctype];
        if (cl == 0) {
                grfmsg(5, "TranslateCargo: Cargo type %d not available in this climate, skipping.", ctype);
                return CT_INVALID;
        }

        ctype = GetCargoIDByLabel(cl);
        if (ctype == CT_INVALID) {
                grfmsg(5, "TranslateCargo: Cargo '%c%c%c%c' unsupported, skipping.", GB(cl, 24, 8), GB(cl, 16, 8), GB(cl, 8, 8), GB(cl, 0, 8));
                return CT_INVALID;
        }

        grfmsg(6, "TranslateCargo: Cargo '%c%c%c%c' mapped to cargo type %d.", GB(cl, 24, 8), GB(cl, 16, 8), GB(cl, 8, 8), GB(cl, 0, 8), ctype);
        return ctype;
}


static bool IsValidGroupID(uint16 groupid, const char *function)
{
        if (groupid > MAX_SPRITEGROUP || _cur.spritegroups[groupid] == nullptr) {
                grfmsg(1, "%s: Spritegroup 0x%04X out of range or empty, skipping.", function, groupid);
                return false;
        }

        return true;
}

static void VehicleMapSpriteGroup(ByteReader *buf, byte feature, uint8 idcount)
{
        static EngineID *last_engines;
        static uint last_engines_count;
        bool wagover = false;

        /* Test for 'wagon override' flag */
        if (HasBit(idcount, 7)) {
                wagover = true;
                /* Strip off the flag */
                idcount = GB(idcount, 0, 7);

                if (last_engines_count == 0) {
                        grfmsg(0, "VehicleMapSpriteGroup: WagonOverride: No engine to do override with");
                        return;
                }

                grfmsg(6, "VehicleMapSpriteGroup: WagonOverride: %u engines, %u wagons",
                                last_engines_count, idcount);
        } else {
                if (last_engines_count != idcount) {
                        last_engines = ReallocT(last_engines, idcount);
                        last_engines_count = idcount;
                }
        }

        EngineID *engines = AllocaM(EngineID, idcount);
        for (uint i = 0; i < idcount; i++) {
                Engine *e = GetNewEngine(_cur.grffile, (VehicleType)feature, buf->ReadExtendedByte());
                if (e == nullptr) {
                        /* No engine could be allocated?!? Deal with it. Okay,
                         * this might look bad. Also make sure this NewGRF
                         * gets disabled, as a half loaded one is bad. */
                        HandleChangeInfoResult("VehicleMapSpriteGroup", CIR_INVALID_ID, 0, 0);
                        return;
                }

                engines[i] = e->index;
                if (!wagover) last_engines[i] = engines[i];
        }

        uint8 cidcount = buf->ReadByte();
        for (uint c = 0; c < cidcount; c++) {
                uint8 ctype = buf->ReadByte();
                uint16 groupid = buf->ReadWord();
                if (!IsValidGroupID(groupid, "VehicleMapSpriteGroup")) continue;

                grfmsg(8, "VehicleMapSpriteGroup: * [%d] Cargo type 0x%X, group id 0x%02X", c, ctype, groupid);

                ctype = TranslateCargo(feature, ctype);
                if (ctype == CT_INVALID) continue;

                for (uint i = 0; i < idcount; i++) {
                        EngineID engine = engines[i];

                        grfmsg(7, "VehicleMapSpriteGroup: [%d] Engine %d...", i, engine);

                        if (wagover) {
                                SetWagonOverrideSprites(engine, ctype, _cur.spritegroups[groupid], last_engines, last_engines_count);
                        } else {
                                SetCustomEngineSprites(engine, ctype, _cur.spritegroups[groupid]);
                        }
                }
        }

        uint16 groupid = buf->ReadWord();
        if (!IsValidGroupID(groupid, "VehicleMapSpriteGroup")) return;

        grfmsg(8, "-- Default group id 0x%04X", groupid);

        for (uint i = 0; i < idcount; i++) {
                EngineID engine = engines[i];

                if (wagover) {
                        SetWagonOverrideSprites(engine, CT_DEFAULT, _cur.spritegroups[groupid], last_engines, last_engines_count);
                } else {
                        SetCustomEngineSprites(engine, CT_DEFAULT, _cur.spritegroups[groupid]);
                        SetEngineGRF(engine, _cur.grffile);
                }
        }
}


static void CanalMapSpriteGroup(ByteReader *buf, uint8 idcount)
{
        CanalFeature *cfs = AllocaM(CanalFeature, idcount);
        for (uint i = 0; i < idcount; i++) {
                cfs[i] = (CanalFeature)buf->ReadByte();
        }

        uint8 cidcount = buf->ReadByte();
        buf->Skip(cidcount * 3);

        uint16 groupid = buf->ReadWord();
        if (!IsValidGroupID(groupid, "CanalMapSpriteGroup")) return;

        for (uint i = 0; i < idcount; i++) {
                CanalFeature cf = cfs[i];

                if (cf >= CF_END) {
                        grfmsg(1, "CanalMapSpriteGroup: Canal subset %d out of range, skipping", cf);
                        continue;
                }

                _water_feature[cf].grffile = _cur.grffile;
                _water_feature[cf].group = _cur.spritegroups[groupid];
        }
}


static void StationMapSpriteGroup(ByteReader *buf, uint8 idcount)
{
        uint8 *stations = AllocaM(uint8, idcount);
        for (uint i = 0; i < idcount; i++) {
                stations[i] = buf->ReadByte();
        }

        uint8 cidcount = buf->ReadByte();
        for (uint c = 0; c < cidcount; c++) {
                uint8 ctype = buf->ReadByte();
                uint16 groupid = buf->ReadWord();
                if (!IsValidGroupID(groupid, "StationMapSpriteGroup")) continue;

                ctype = TranslateCargo(GSF_STATIONS, ctype);
                if (ctype == CT_INVALID) continue;

                for (uint i = 0; i < idcount; i++) {
                        StationSpec *statspec = _cur.grffile->stations == nullptr ? nullptr : _cur.grffile->stations[stations[i]];

                        if (statspec == nullptr) {
                                grfmsg(1, "StationMapSpriteGroup: Station with ID 0x%02X does not exist, skipping", stations[i]);
                                continue;
                        }

                        statspec->grf_prop.spritegroup[ctype] = _cur.spritegroups[groupid];
                }
        }

        uint16 groupid = buf->ReadWord();
        if (!IsValidGroupID(groupid, "StationMapSpriteGroup")) return;

        for (uint i = 0; i < idcount; i++) {
                StationSpec *statspec = _cur.grffile->stations == nullptr ? nullptr : _cur.grffile->stations[stations[i]];

                if (statspec == nullptr) {
                        grfmsg(1, "StationMapSpriteGroup: Station with ID 0x%02X does not exist, skipping", stations[i]);
                        continue;
                }

                if (statspec->grf_prop.grffile != nullptr) {
                        grfmsg(1, "StationMapSpriteGroup: Station with ID 0x%02X mapped multiple times, skipping", stations[i]);
                        continue;
                }

                statspec->grf_prop.spritegroup[CT_DEFAULT] = _cur.spritegroups[groupid];
                statspec->grf_prop.grffile = _cur.grffile;
                statspec->grf_prop.local_id = stations[i];
                StationClass::Assign(statspec);
        }
}


static void TownHouseMapSpriteGroup(ByteReader *buf, uint8 idcount)
{
        uint8 *houses = AllocaM(uint8, idcount);
        for (uint i = 0; i < idcount; i++) {
                houses[i] = buf->ReadByte();
        }

        /* Skip the cargo type section, we only care about the default group */
        uint8 cidcount = buf->ReadByte();
        buf->Skip(cidcount * 3);

        uint16 groupid = buf->ReadWord();
        if (!IsValidGroupID(groupid, "TownHouseMapSpriteGroup")) return;

        if (_cur.grffile->housespec == nullptr) {
                grfmsg(1, "TownHouseMapSpriteGroup: No houses defined, skipping");
                return;
        }

        for (uint i = 0; i < idcount; i++) {
                HouseSpec *hs = _cur.grffile->housespec[houses[i]];

                if (hs == nullptr) {
                        grfmsg(1, "TownHouseMapSpriteGroup: House %d undefined, skipping.", houses[i]);
                        continue;
                }

                hs->grf_prop.spritegroup[0] = _cur.spritegroups[groupid];
        }
}

static void IndustryMapSpriteGroup(ByteReader *buf, uint8 idcount)
{
        uint8 *industries = AllocaM(uint8, idcount);
        for (uint i = 0; i < idcount; i++) {
                industries[i] = buf->ReadByte();
        }

        /* Skip the cargo type section, we only care about the default group */
        uint8 cidcount = buf->ReadByte();
        buf->Skip(cidcount * 3);

        uint16 groupid = buf->ReadWord();
        if (!IsValidGroupID(groupid, "IndustryMapSpriteGroup")) return;

        if (_cur.grffile->industryspec == nullptr) {
                grfmsg(1, "IndustryMapSpriteGroup: No industries defined, skipping");
                return;
        }

        for (uint i = 0; i < idcount; i++) {
                IndustrySpec *indsp = _cur.grffile->industryspec[industries[i]];

                if (indsp == nullptr) {
                        grfmsg(1, "IndustryMapSpriteGroup: Industry %d undefined, skipping", industries[i]);
                        continue;
                }

                indsp->grf_prop.spritegroup[0] = _cur.spritegroups[groupid];
        }
}

static void IndustrytileMapSpriteGroup(ByteReader *buf, uint8 idcount)
{
        uint8 *indtiles = AllocaM(uint8, idcount);
        for (uint i = 0; i < idcount; i++) {
                indtiles[i] = buf->ReadByte();
        }

        /* Skip the cargo type section, we only care about the default group */
        uint8 cidcount = buf->ReadByte();
        buf->Skip(cidcount * 3);

        uint16 groupid = buf->ReadWord();
        if (!IsValidGroupID(groupid, "IndustrytileMapSpriteGroup")) return;

        if (_cur.grffile->indtspec == nullptr) {
                grfmsg(1, "IndustrytileMapSpriteGroup: No industry tiles defined, skipping");
                return;
        }

        for (uint i = 0; i < idcount; i++) {
                IndustryTileSpec *indtsp = _cur.grffile->indtspec[indtiles[i]];

                if (indtsp == nullptr) {
                        grfmsg(1, "IndustrytileMapSpriteGroup: Industry tile %d undefined, skipping", indtiles[i]);
                        continue;
                }

                indtsp->grf_prop.spritegroup[0] = _cur.spritegroups[groupid];
        }
}

static void CargoMapSpriteGroup(ByteReader *buf, uint8 idcount)
{
        CargoID *cargoes = AllocaM(CargoID, idcount);
        for (uint i = 0; i < idcount; i++) {
                cargoes[i] = buf->ReadByte();
        }

        /* Skip the cargo type section, we only care about the default group */
        uint8 cidcount = buf->ReadByte();
        buf->Skip(cidcount * 3);

        uint16 groupid = buf->ReadWord();
        if (!IsValidGroupID(groupid, "CargoMapSpriteGroup")) return;

        for (uint i = 0; i < idcount; i++) {
                CargoID cid = cargoes[i];

                if (cid >= NUM_CARGO) {
                        grfmsg(1, "CargoMapSpriteGroup: Cargo ID %d out of range, skipping", cid);
                        continue;
                }

                CargoSpec *cs = CargoSpec::Get(cid);
                cs->grffile = _cur.grffile;
                cs->group = _cur.spritegroups[groupid];
        }
}

static void ObjectMapSpriteGroup(ByteReader *buf, uint8 idcount)
{
        if (_cur.grffile->objectspec == nullptr) {
                grfmsg(1, "ObjectMapSpriteGroup: No object tiles defined, skipping");
                return;
        }

        uint8 *objects = AllocaM(uint8, idcount);
        for (uint i = 0; i < idcount; i++) {
                objects[i] = buf->ReadByte();
        }

        uint8 cidcount = buf->ReadByte();
        for (uint c = 0; c < cidcount; c++) {
                uint8 ctype = buf->ReadByte();
                uint16 groupid = buf->ReadWord();
                if (!IsValidGroupID(groupid, "ObjectMapSpriteGroup")) continue;

                ctype = TranslateCargo(GSF_OBJECTS, ctype);
                if (ctype == CT_INVALID) continue;

                for (uint i = 0; i < idcount; i++) {
                        ObjectSpec *spec = _cur.grffile->objectspec[objects[i]];

                        if (spec == nullptr) {
                                grfmsg(1, "ObjectMapSpriteGroup: Object with ID 0x%02X undefined, skipping", objects[i]);
                                continue;
                        }

                        spec->grf_prop.spritegroup[ctype] = _cur.spritegroups[groupid];
                }
        }

        uint16 groupid = buf->ReadWord();
        if (!IsValidGroupID(groupid, "ObjectMapSpriteGroup")) return;

        for (uint i = 0; i < idcount; i++) {
                ObjectSpec *spec = _cur.grffile->objectspec[objects[i]];

                if (spec == nullptr) {
                        grfmsg(1, "ObjectMapSpriteGroup: Object with ID 0x%02X undefined, skipping", objects[i]);
                        continue;
                }

                if (spec->grf_prop.grffile != nullptr) {
                        grfmsg(1, "ObjectMapSpriteGroup: Object with ID 0x%02X mapped multiple times, skipping", objects[i]);
                        continue;
                }

                spec->grf_prop.spritegroup[0] = _cur.spritegroups[groupid];
                spec->grf_prop.grffile        = _cur.grffile;
                spec->grf_prop.local_id       = objects[i];
        }
}

static void RailTypeMapSpriteGroup(ByteReader *buf, uint8 idcount)
{
        uint8 *railtypes = AllocaM(uint8, idcount);
        for (uint i = 0; i < idcount; i++) {
                railtypes[i] = _cur.grffile->railtype_map[buf->ReadByte()];
        }

        uint8 cidcount = buf->ReadByte();
        for (uint c = 0; c < cidcount; c++) {
                uint8 ctype = buf->ReadByte();
                uint16 groupid = buf->ReadWord();
                if (!IsValidGroupID(groupid, "RailTypeMapSpriteGroup")) continue;

                if (ctype >= RTSG_END) continue;

                extern RailtypeInfo _railtypes[RAILTYPE_END];
                for (uint i = 0; i < idcount; i++) {
                        if (railtypes[i] != INVALID_RAILTYPE) {
                                RailtypeInfo *rti = &_railtypes[railtypes[i]];

                                rti->grffile[ctype] = _cur.grffile;
                                rti->group[ctype] = _cur.spritegroups[groupid];
                        }
                }
        }

        /* Railtypes do not use the default group. */
        buf->ReadWord();
}

static void RoadTypeMapSpriteGroup(ByteReader *buf, uint8 idcount, RoadType basetype)
{
        uint8 *roadtypes = AllocaM(uint8, idcount);
        for (uint i = 0; i < idcount; i++) {
                roadtypes[i] = _cur.grffile->roadtype_map[basetype][buf->ReadByte()];
        }

        uint8 cidcount = buf->ReadByte();
        for (uint c = 0; c < cidcount; c++) {
                uint8 ctype = buf->ReadByte();
                uint16 groupid = buf->ReadWord();
                if (!IsValidGroupID(groupid, "RoadTypeMapSpriteGroup")) continue;

                if (ctype >= ROTSG_END) continue;

                extern RoadtypeInfo _roadtypes[ROADTYPE_END][ROADSUBTYPE_END];
                for (uint i = 0; i < idcount; i++) {
                        if (roadtypes[i] != INVALID_ROADSUBTYPE) {
                                RoadtypeInfo *rti = &_roadtypes[basetype][roadtypes[i]];

                                rti->grffile[ctype] = _cur.grffile;
                                rti->group[ctype] = _cur.spritegroups[groupid];
                        }
                }
        }

        /* Roadtypes do not use the default group. */
        buf->ReadWord();
}

static void AirportMapSpriteGroup(ByteReader *buf, uint8 idcount)
{
        uint8 *airports = AllocaM(uint8, idcount);
        for (uint i = 0; i < idcount; i++) {
                airports[i] = buf->ReadByte();
        }

        /* Skip the cargo type section, we only care about the default group */
        uint8 cidcount = buf->ReadByte();
        buf->Skip(cidcount * 3);

        uint16 groupid = buf->ReadWord();
        if (!IsValidGroupID(groupid, "AirportMapSpriteGroup")) return;

        if (_cur.grffile->airportspec == nullptr) {
                grfmsg(1, "AirportMapSpriteGroup: No airports defined, skipping");
                return;
        }

        for (uint i = 0; i < idcount; i++) {
                AirportSpec *as = _cur.grffile->airportspec[airports[i]];

                if (as == nullptr) {
                        grfmsg(1, "AirportMapSpriteGroup: Airport %d undefined, skipping", airports[i]);
                        continue;
                }

                as->grf_prop.spritegroup[0] = _cur.spritegroups[groupid];
        }
}

static void AirportTileMapSpriteGroup(ByteReader *buf, uint8 idcount)
{
        uint8 *airptiles = AllocaM(uint8, idcount);
        for (uint i = 0; i < idcount; i++) {
                airptiles[i] = buf->ReadByte();
        }

        /* Skip the cargo type section, we only care about the default group */
        uint8 cidcount = buf->ReadByte();
        buf->Skip(cidcount * 3);

        uint16 groupid = buf->ReadWord();
        if (!IsValidGroupID(groupid, "AirportTileMapSpriteGroup")) return;

        if (_cur.grffile->airtspec == nullptr) {
                grfmsg(1, "AirportTileMapSpriteGroup: No airport tiles defined, skipping");
                return;
        }

        for (uint i = 0; i < idcount; i++) {
                AirportTileSpec *airtsp = _cur.grffile->airtspec[airptiles[i]];

                if (airtsp == nullptr) {
                        grfmsg(1, "AirportTileMapSpriteGroup: Airport tile %d undefined, skipping", airptiles[i]);
                        continue;
                }

                airtsp->grf_prop.spritegroup[0] = _cur.spritegroups[groupid];
        }
}


/* Action 0x03 */
static void FeatureMapSpriteGroup(ByteReader *buf)
{
        /* <03> <feature> <n-id> <ids>... <num-cid> [<cargo-type> <cid>]... <def-cid>
         * id-list    := [<id>] [id-list]
         * cargo-list := <cargo-type> <cid> [cargo-list]
         *
         * B feature       see action 0
         * B n-id          bits 0-6: how many IDs this definition applies to
         *                 bit 7: if set, this is a wagon override definition (see below)
         * B ids           the IDs for which this definition applies
         * B num-cid       number of cargo IDs (sprite group IDs) in this definition
         *                 can be zero, in that case the def-cid is used always
         * B cargo-type    type of this cargo type (e.g. mail=2, wood=7, see below)
         * W cid           cargo ID (sprite group ID) for this type of cargo
         * W def-cid       default cargo ID (sprite group ID) */

        uint8 feature = buf->ReadByte();
        uint8 idcount = buf->ReadByte();

        /* If idcount is zero, this is a feature callback */
        if (idcount == 0) {
                /* Skip number of cargo ids? */
                buf->ReadByte();
                uint16 groupid = buf->ReadWord();
                if (!IsValidGroupID(groupid, "FeatureMapSpriteGroup")) return;

                grfmsg(6, "FeatureMapSpriteGroup: Adding generic feature callback for feature %d", feature);

                AddGenericCallback(feature, _cur.grffile, _cur.spritegroups[groupid]);
                return;
        }

        /* Mark the feature as used by the grf (generic callbacks do not count) */
        SetBit(_cur.grffile->grf_features, feature);

        grfmsg(6, "FeatureMapSpriteGroup: Feature %d, %d ids", feature, idcount);

        switch (feature) {
                case GSF_TRAINS:
                case GSF_ROADVEHICLES:
                case GSF_SHIPS:
                case GSF_AIRCRAFT:
                        VehicleMapSpriteGroup(buf, feature, idcount);
                        return;

                case GSF_CANALS:
                        CanalMapSpriteGroup(buf, idcount);
                        return;

                case GSF_STATIONS:
                        StationMapSpriteGroup(buf, idcount);
                        return;

                case GSF_HOUSES:
                        TownHouseMapSpriteGroup(buf, idcount);
                        return;

                case GSF_INDUSTRIES:
                        IndustryMapSpriteGroup(buf, idcount);
                        return;

                case GSF_INDUSTRYTILES:
                        IndustrytileMapSpriteGroup(buf, idcount);
                        return;

                case GSF_CARGOES:
                        CargoMapSpriteGroup(buf, idcount);
                        return;

                case GSF_AIRPORTS:
                        AirportMapSpriteGroup(buf, idcount);
                        return;

                case GSF_OBJECTS:
                        ObjectMapSpriteGroup(buf, idcount);
                        break;

                case GSF_RAILTYPES:
                        RailTypeMapSpriteGroup(buf, idcount);
                        break;

                case GSF_ROADTYPES:
                        RoadTypeMapSpriteGroup(buf, idcount, ROADTYPE_ROAD);
                        break;

                case GSF_TRAMTYPES:
                        RoadTypeMapSpriteGroup(buf, idcount, ROADTYPE_TRAM);
                        break;

                case GSF_AIRPORTTILES:
                        AirportTileMapSpriteGroup(buf, idcount);
                        return;

                default:
                        grfmsg(1, "FeatureMapSpriteGroup: Unsupported feature %d, skipping", feature);
                        return;
        }
}

/* Action 0x04 */
static void FeatureNewName(ByteReader *buf)
{
        /* <04> <veh-type> <language-id> <num-veh> <offset> <data...>
         *
         * B veh-type      see action 0 (as 00..07, + 0A
         *                 But IF veh-type = 48, then generic text
         * B language-id   If bit 6 is set, This is the extended language scheme,
         *                 with up to 64 language.
         *                 Otherwise, it is a mapping where set bits have meaning
         *                 0 = american, 1 = english, 2 = german, 3 = french, 4 = spanish
         *                 Bit 7 set means this is a generic text, not a vehicle one (or else)
         * B num-veh       number of vehicles which are getting a new name
         * B/W offset      number of the first vehicle that gets a new name
         *                 Byte : ID of vehicle to change
         *                 Word : ID of string to change/add
         * S data          new texts, each of them zero-terminated, after
         *                 which the next name begins. */

        bool new_scheme = _cur.grffile->grf_version >= 7;

        uint8 feature  = buf->ReadByte();
        uint8 lang     = buf->ReadByte();
        uint8 num      = buf->ReadByte();
        bool generic   = HasBit(lang, 7);
        uint16 id;
        if (generic) {
                id = buf->ReadWord();
        } else if (feature <= GSF_AIRCRAFT) {
                id = buf->ReadExtendedByte();
        } else {
                id = buf->ReadByte();
        }

        ClrBit(lang, 7);

        uint16 endid = id + num;

        grfmsg(6, "FeatureNewName: About to rename engines %d..%d (feature %d) in language 0x%02X",
                                   id, endid, feature, lang);

        for (; id < endid && buf->HasData(); id++) {
                const char *name = buf->ReadString();
                grfmsg(8, "FeatureNewName: 0x%04X <- %s", id, name);

                switch (feature) {
                        case GSF_TRAINS:
                        case GSF_ROADVEHICLES:
                        case GSF_SHIPS:
                        case GSF_AIRCRAFT:
                                if (!generic) {
                                        Engine *e = GetNewEngine(_cur.grffile, (VehicleType)feature, id, HasBit(_cur.grfconfig->flags, GCF_STATIC));
                                        if (e == nullptr) break;
                                        StringID string = AddGRFString(_cur.grffile->grfid, e->index, lang, new_scheme, false, name, e->info.string_id);
                                        e->info.string_id = string;
                                } else {
                                        AddGRFString(_cur.grffile->grfid, id, lang, new_scheme, true, name, STR_UNDEFINED);
                                }
                                break;

                        default:
                                if (IsInsideMM(id, 0xD000, 0xD400) || IsInsideMM(id, 0xD800, 0xE000)) {
                                        AddGRFString(_cur.grffile->grfid, id, lang, new_scheme, true, name, STR_UNDEFINED);
                                        break;
                                }

                                switch (GB(id, 8, 8)) {
                                        case 0xC4: // Station class name
                                                if (_cur.grffile->stations == nullptr || _cur.grffile->stations[GB(id, 0, 8)] == nullptr) {
                                                        grfmsg(1, "FeatureNewName: Attempt to name undefined station 0x%X, ignoring", GB(id, 0, 8));
                                                } else {
                                                        StationClassID cls_id = _cur.grffile->stations[GB(id, 0, 8)]->cls_id;
                                                        StationClass::Get(cls_id)->name = AddGRFString(_cur.grffile->grfid, id, lang, new_scheme, false, name, STR_UNDEFINED);
                                                }
                                                break;

                                        case 0xC5: // Station name
                                                if (_cur.grffile->stations == nullptr || _cur.grffile->stations[GB(id, 0, 8)] == nullptr) {
                                                        grfmsg(1, "FeatureNewName: Attempt to name undefined station 0x%X, ignoring", GB(id, 0, 8));
                                                } else {
                                                        _cur.grffile->stations[GB(id, 0, 8)]->name = AddGRFString(_cur.grffile->grfid, id, lang, new_scheme, false, name, STR_UNDEFINED);
                                                }
                                                break;

                                        case 0xC7: // Airporttile name
                                                if (_cur.grffile->airtspec == nullptr || _cur.grffile->airtspec[GB(id, 0, 8)] == nullptr) {
                                                        grfmsg(1, "FeatureNewName: Attempt to name undefined airport tile 0x%X, ignoring", GB(id, 0, 8));
                                                } else {
                                                        _cur.grffile->airtspec[GB(id, 0, 8)]->name = AddGRFString(_cur.grffile->grfid, id, lang, new_scheme, false, name, STR_UNDEFINED);
                                                }
                                                break;

                                        case 0xC9: // House name
                                                if (_cur.grffile->housespec == nullptr || _cur.grffile->housespec[GB(id, 0, 8)] == nullptr) {
                                                        grfmsg(1, "FeatureNewName: Attempt to name undefined house 0x%X, ignoring.", GB(id, 0, 8));
                                                } else {
                                                        _cur.grffile->housespec[GB(id, 0, 8)]->building_name = AddGRFString(_cur.grffile->grfid, id, lang, new_scheme, false, name, STR_UNDEFINED);
                                                }
                                                break;

                                        default:
                                                grfmsg(7, "FeatureNewName: Unsupported ID (0x%04X)", id);
                                                break;
                                }
                                break;
                }
        }
}

/**
 * Sanitize incoming sprite offsets for Action 5 graphics replacements.
 * @param num         The number of sprites to load.
 * @param offset      Offset from the base.
 * @param max_sprites The maximum number of sprites that can be loaded in this action 5.
 * @param name        Used for error warnings.
 * @return The number of sprites that is going to be skipped.
 */
static uint16 SanitizeSpriteOffset(uint16& num, uint16 offset, int max_sprites, const char *name)
{

        if (offset >= max_sprites) {
                grfmsg(1, "GraphicsNew: %s sprite offset must be less than %i, skipping", name, max_sprites);
                uint orig_num = num;
                num = 0;
                return orig_num;
        }

        if (offset + num > max_sprites) {
                grfmsg(4, "GraphicsNew: %s sprite overflow, truncating...", name);
                uint orig_num = num;
                num = max(max_sprites - offset, 0);
                return orig_num - num;
        }

        return 0;
}


/** The type of action 5 type. */
enum Action5BlockType {
        A5BLOCK_FIXED,                ///< Only allow replacing a whole block of sprites. (TTDP compatible)
        A5BLOCK_ALLOW_OFFSET,         ///< Allow replacing any subset by specifiing an offset.
        A5BLOCK_INVALID,              ///< unknown/not-implemented type
};
/** Information about a single action 5 type. */
struct Action5Type {
        Action5BlockType block_type;  ///< How is this Action5 type processed?
        SpriteID sprite_base;         ///< Load the sprites starting from this sprite.
        uint16 min_sprites;           ///< If the Action5 contains less sprites, the whole block will be ignored.
        uint16 max_sprites;           ///< If the Action5 contains more sprites, only the first max_sprites sprites will be used.
        const char *name;             ///< Name for error messages.
};

/** The information about action 5 types. */
static const Action5Type _action5_types[] = {
        /* Note: min_sprites should not be changed. Therefore these constants are directly here and not in sprites.h */
        /* 0x00 */ { A5BLOCK_INVALID,      0,                            0, 0,                                           "Type 0x00"                },
        /* 0x01 */ { A5BLOCK_INVALID,      0,                            0, 0,                                           "Type 0x01"                },
        /* 0x02 */ { A5BLOCK_INVALID,      0,                            0, 0,                                           "Type 0x02"                },
        /* 0x03 */ { A5BLOCK_INVALID,      0,                            0, 0,                                           "Type 0x03"                },
        /* 0x04 */ { A5BLOCK_ALLOW_OFFSET, SPR_SIGNALS_BASE,             1, PRESIGNAL_SEMAPHORE_AND_PBS_SPRITE_COUNT,    "Signal graphics"          },
        /* 0x05 */ { A5BLOCK_ALLOW_OFFSET, SPR_ELRAIL_BASE,              1, ELRAIL_SPRITE_COUNT,                         "Rail catenary graphics"   },
        /* 0x06 */ { A5BLOCK_ALLOW_OFFSET, SPR_SLOPES_BASE,              1, NORMAL_AND_HALFTILE_FOUNDATION_SPRITE_COUNT, "Foundation graphics"      },
        /* 0x07 */ { A5BLOCK_INVALID,      0,                           75, 0,                                           "TTDP GUI graphics"        }, // Not used by OTTD.
        /* 0x08 */ { A5BLOCK_ALLOW_OFFSET, SPR_CANALS_BASE,              1, CANALS_SPRITE_COUNT,                         "Canal graphics"           },
        /* 0x09 */ { A5BLOCK_ALLOW_OFFSET, SPR_ONEWAY_BASE,              1, ONEWAY_SPRITE_COUNT,                         "One way road graphics"    },
        /* 0x0A */ { A5BLOCK_ALLOW_OFFSET, SPR_2CCMAP_BASE,              1, TWOCCMAP_SPRITE_COUNT,                       "2CC colour maps"          },
        /* 0x0B */ { A5BLOCK_ALLOW_OFFSET, SPR_TRAMWAY_BASE,             1, TRAMWAY_SPRITE_COUNT,                        "Tramway graphics"         },
        /* 0x0C */ { A5BLOCK_INVALID,      0,                          133, 0,                                           "Snowy temperate tree"     }, // Not yet used by OTTD.
        /* 0x0D */ { A5BLOCK_FIXED,        SPR_SHORE_BASE,              16, SPR_SHORE_SPRITE_COUNT,                      "Shore graphics"           },
        /* 0x0E */ { A5BLOCK_INVALID,      0,                            0, 0,                                           "New Signals graphics"     }, // Not yet used by OTTD.
        /* 0x0F */ { A5BLOCK_ALLOW_OFFSET, SPR_TRACKS_FOR_SLOPES_BASE,   1, TRACKS_FOR_SLOPES_SPRITE_COUNT,              "Sloped rail track"        },
        /* 0x10 */ { A5BLOCK_ALLOW_OFFSET, SPR_AIRPORTX_BASE,            1, AIRPORTX_SPRITE_COUNT,                       "Airport graphics"         },
        /* 0x11 */ { A5BLOCK_ALLOW_OFFSET, SPR_ROADSTOP_BASE,            1, ROADSTOP_SPRITE_COUNT,                       "Road stop graphics"       },
        /* 0x12 */ { A5BLOCK_ALLOW_OFFSET, SPR_AQUEDUCT_BASE,            1, AQUEDUCT_SPRITE_COUNT,                       "Aqueduct graphics"        },
        /* 0x13 */ { A5BLOCK_ALLOW_OFFSET, SPR_AUTORAIL_BASE,            1, AUTORAIL_SPRITE_COUNT,                       "Autorail graphics"        },
        /* 0x14 */ { A5BLOCK_ALLOW_OFFSET, SPR_FLAGS_BASE,               1, FLAGS_SPRITE_COUNT,                          "Flag graphics"            },
        /* 0x15 */ { A5BLOCK_ALLOW_OFFSET, SPR_OPENTTD_BASE,             1, OPENTTD_SPRITE_COUNT,                        "OpenTTD GUI graphics"     },
        /* 0x16 */ { A5BLOCK_ALLOW_OFFSET, SPR_AIRPORT_PREVIEW_BASE,     1, SPR_AIRPORT_PREVIEW_COUNT,                   "Airport preview graphics" },
        /* 0x17 */ { A5BLOCK_ALLOW_OFFSET, SPR_RAILTYPE_TUNNEL_BASE,     1, RAILTYPE_TUNNEL_BASE_COUNT,                  "Railtype tunnel base"     },
        /* 0x18 */ { A5BLOCK_ALLOW_OFFSET, SPR_PALETTE_BASE,             1, PALETTE_SPRITE_COUNT,                        "Palette"                  },
};

/* Action 0x05 */
static void GraphicsNew(ByteReader *buf)
{
        /* <05> <graphics-type> <num-sprites> <other data...>
         *
         * B graphics-type What set of graphics the sprites define.
         * E num-sprites   How many sprites are in this set?
         * V other data    Graphics type specific data.  Currently unused. */
        /* TODO */

        uint8 type = buf->ReadByte();
        uint16 num = buf->ReadExtendedByte();
        uint16 offset = HasBit(type, 7) ? buf->ReadExtendedByte() : 0;
        ClrBit(type, 7); // Clear the high bit as that only indicates whether there is an offset.

        if ((type == 0x0D) && (num == 10) && HasBit(_cur.grfconfig->flags, GCF_SYSTEM)) {
                /* Special not-TTDP-compatible case used in openttd.grf
                 * Missing shore sprites and initialisation of SPR_SHORE_BASE */
                grfmsg(2, "GraphicsNew: Loading 10 missing shore sprites from extra grf.");
                LoadNextSprite(SPR_SHORE_BASE +  0, _cur.file_index, _cur.nfo_line++, _cur.grf_container_ver); // SLOPE_STEEP_S
                LoadNextSprite(SPR_SHORE_BASE +  5, _cur.file_index, _cur.nfo_line++, _cur.grf_container_ver); // SLOPE_STEEP_W
                LoadNextSprite(SPR_SHORE_BASE +  7, _cur.file_index, _cur.nfo_line++, _cur.grf_container_ver); // SLOPE_WSE
                LoadNextSprite(SPR_SHORE_BASE + 10, _cur.file_index, _cur.nfo_line++, _cur.grf_container_ver); // SLOPE_STEEP_N
                LoadNextSprite(SPR_SHORE_BASE + 11, _cur.file_index, _cur.nfo_line++, _cur.grf_container_ver); // SLOPE_NWS
                LoadNextSprite(SPR_SHORE_BASE + 13, _cur.file_index, _cur.nfo_line++, _cur.grf_container_ver); // SLOPE_ENW
                LoadNextSprite(SPR_SHORE_BASE + 14, _cur.file_index, _cur.nfo_line++, _cur.grf_container_ver); // SLOPE_SEN
                LoadNextSprite(SPR_SHORE_BASE + 15, _cur.file_index, _cur.nfo_line++, _cur.grf_container_ver); // SLOPE_STEEP_E
                LoadNextSprite(SPR_SHORE_BASE + 16, _cur.file_index, _cur.nfo_line++, _cur.grf_container_ver); // SLOPE_EW
                LoadNextSprite(SPR_SHORE_BASE + 17, _cur.file_index, _cur.nfo_line++, _cur.grf_container_ver); // SLOPE_NS
                if (_loaded_newgrf_features.shore == SHORE_REPLACE_NONE) _loaded_newgrf_features.shore = SHORE_REPLACE_ONLY_NEW;
                return;
        }

        /* Supported type? */
        if ((type >= lengthof(_action5_types)) || (_action5_types[type].block_type == A5BLOCK_INVALID)) {
                grfmsg(2, "GraphicsNew: Custom graphics (type 0x%02X) sprite block of length %u (unimplemented, ignoring)", type, num);
                _cur.skip_sprites = num;
                return;
        }

        const Action5Type *action5_type = &_action5_types[type];

        /* Contrary to TTDP we allow always to specify too few sprites as we allow always an offset,
         * except for the long version of the shore type:
         * Ignore offset if not allowed */
        if ((action5_type->block_type != A5BLOCK_ALLOW_OFFSET) && (offset != 0)) {
                grfmsg(1, "GraphicsNew: %s (type 0x%02X) do not allow an <offset> field. Ignoring offset.", action5_type->name, type);
                offset = 0;
        }

        /* Ignore action5 if too few sprites are specified. (for TTDP compatibility)
         * This does not make sense, if <offset> is allowed */
        if ((action5_type->block_type == A5BLOCK_FIXED) && (num < action5_type->min_sprites)) {
                grfmsg(1, "GraphicsNew: %s (type 0x%02X) count must be at least %d. Only %d were specified. Skipping.", action5_type->name, type, action5_type->min_sprites, num);
                _cur.skip_sprites = num;
                return;
        }

        /* Load at most max_sprites sprites. Skip remaining sprites. (for compatibility with TTDP and future extentions) */
        uint16 skip_num = SanitizeSpriteOffset(num, offset, action5_type->max_sprites, action5_type->name);
        SpriteID replace = action5_type->sprite_base + offset;

        /* Load <num> sprites starting from <replace>, then skip <skip_num> sprites. */
        grfmsg(2, "GraphicsNew: Replacing sprites %d to %d of %s (type 0x%02X) at SpriteID 0x%04X", offset, offset + num - 1, action5_type->name, type, replace);

        if (type == 0x0D) _loaded_newgrf_features.shore = SHORE_REPLACE_ACTION_5;

        if (type == 0x0B) {
                static const SpriteID depot_with_track_offset = SPR_TRAMWAY_DEPOT_WITH_TRACK - SPR_TRAMWAY_BASE;
                static const SpriteID depot_no_track_offset = SPR_TRAMWAY_DEPOT_NO_TRACK - SPR_TRAMWAY_BASE;
                if (offset <= depot_with_track_offset && offset + num > depot_with_track_offset) _loaded_newgrf_features.tram = TRAMWAY_REPLACE_DEPOT_WITH_TRACK;
                if (offset <= depot_no_track_offset && offset + num > depot_no_track_offset) _loaded_newgrf_features.tram = TRAMWAY_REPLACE_DEPOT_NO_TRACK;
        }

        for (; num > 0; num--) {
                _cur.nfo_line++;
                LoadNextSprite(replace == 0 ? _cur.spriteid++ : replace++, _cur.file_index, _cur.nfo_line, _cur.grf_container_ver);
        }

        _cur.skip_sprites = skip_num;
}

/* Action 0x05 (SKIP) */
static void SkipAct5(ByteReader *buf)
{
        /* Ignore type byte */
        buf->ReadByte();

        /* Skip the sprites of this action */
        _cur.skip_sprites = buf->ReadExtendedByte();

        grfmsg(3, "SkipAct5: Skipping %d sprites", _cur.skip_sprites);
}

/**
 * Reads a variable common to VarAction2 and Action7/9/D.
 *
 * Returns VarAction2 variable 'param' resp. Action7/9/D variable '0x80 + param'.
 * If a variable is not accessible from all four actions, it is handled in the action specific functions.
 *
 * @param param variable number (as for VarAction2, for Action7/9/D you have to subtract 0x80 first).
 * @param value returns the value of the variable.
 * @param grffile NewGRF querying the variable
 * @return true iff the variable is known and the value is returned in 'value'.
 */
bool GetGlobalVariable(byte param, uint32 *value, const GRFFile *grffile)
{
        switch (param) {
                case 0x00: // current date
                        *value = max(_date - DAYS_TILL_ORIGINAL_BASE_YEAR, 0);
                        return true;

                case 0x01: // current year
                        *value = Clamp(_cur_year, ORIGINAL_BASE_YEAR, ORIGINAL_MAX_YEAR) - ORIGINAL_BASE_YEAR;
                        return true;

                case 0x02: { // detailed date information: month of year (bit 0-7), day of month (bit 8-12), leap year (bit 15), day of year (bit 16-24)
                        Date start_of_year = ConvertYMDToDate(_cur_date_ymd.year, 0, 1);
                        *value = _cur_date_ymd.month | (_cur_date_ymd.day - 1) << 8 | (IsLeapYear(_cur_date_ymd.year) ? 1 << 15 : 0) | (_date - start_of_year) << 16;
                        return true;
                }

                case 0x03: // current climate, 0=temp, 1=arctic, 2=trop, 3=toyland
                        *value = _settings_game.game_creation.landscape;
                        return true;

                case 0x06: // road traffic side, bit 4 clear=left, set=right
                        *value = _settings_game.vehicle.road_side << 4;
                        return true;

                case 0x09: // date fraction
                        *value = _date_fract * 885;
                        return true;

                case 0x0A: // animation counter
                        *value = _tick_counter;
                        return true;

                case 0x0B: { // TTDPatch version
                        uint major    = 2;
                        uint minor    = 6;
                        uint revision = 1; // special case: 2.0.1 is 2.0.10
                        uint build    = 1382;
                        *value = (major << 24) | (minor << 20) | (revision << 16) | build;
                        return true;
                }

                case 0x0D: // TTD Version, 00=DOS, 01=Windows
                        *value = _cur.grfconfig->palette & GRFP_USE_MASK;
                        return true;

                case 0x0E: // Y-offset for train sprites
                        *value = _cur.grffile->traininfo_vehicle_pitch;
                        return true;

                case 0x0F: // Rail track type cost factors
                        *value = 0;
                        SB(*value, 0, 8, GetRailTypeInfo(RAILTYPE_RAIL)->cost_multiplier); // normal rail
                        if (_settings_game.vehicle.disable_elrails) {
                                /* skip elrail multiplier - disabled */
                                SB(*value, 8, 8, GetRailTypeInfo(RAILTYPE_MONO)->cost_multiplier); // monorail
                        } else {
                                SB(*value, 8, 8, GetRailTypeInfo(RAILTYPE_ELECTRIC)->cost_multiplier); // electified railway
                                /* Skip monorail multiplier - no space in result */
                        }
                        SB(*value, 16, 8, GetRailTypeInfo(RAILTYPE_MAGLEV)->cost_multiplier); // maglev
                        return true;

                case 0x11: // current rail tool type
                        *value = 0; // constant fake value to avoid desync
                        return true;

                case 0x12: // Game mode
                        *value = _game_mode;
                        return true;

                /* case 0x13: // Tile refresh offset to left    not implemented */
                /* case 0x14: // Tile refresh offset to right   not implemented */
                /* case 0x15: // Tile refresh offset upwards    not implemented */
                /* case 0x16: // Tile refresh offset downwards  not implemented */
                /* case 0x17: // temperate snow line            not implemented */

                case 0x1A: // Always -1
                        *value = UINT_MAX;
                        return true;

                case 0x1B: // Display options
                        *value = 0x3F; // constant fake value to avoid desync
                        return true;

                case 0x1D: // TTD Platform, 00=TTDPatch, 01=OpenTTD
                        *value = 1;
                        return true;

                case 0x1E: // Miscellaneous GRF features
                        *value = _misc_grf_features;

                        /* Add the local flags */
                        assert(!HasBit(*value, GMB_TRAIN_WIDTH_32_PIXELS));
                        if (_cur.grffile->traininfo_vehicle_width == VEHICLEINFO_FULL_VEHICLE_WIDTH) SetBit(*value, GMB_TRAIN_WIDTH_32_PIXELS);
                        return true;

                /* case 0x1F: // locale dependent settings not implemented to avoid desync */

                case 0x20: { // snow line height
                        byte snowline = GetSnowLine();
                        if (_settings_game.game_creation.landscape == LT_ARCTIC && snowline <= _settings_game.construction.max_heightlevel) {
                                *value = Clamp(snowline * (grffile->grf_version >= 8 ? 1 : TILE_HEIGHT), 0, 0xFE);
                        } else {
                                /* No snow */
                                *value = 0xFF;
                        }
                        return true;
                }

                case 0x21: // OpenTTD version
                        *value = _openttd_newgrf_version;
                        return true;

                case 0x22: // difficulty level
                        *value = SP_CUSTOM;
                        return true;

                case 0x23: // long format date
                        *value = _date;
                        return true;

                case 0x24: // long format year
                        *value = _cur_year;
                        return true;

                default: return false;
        }
}

static uint32 GetParamVal(byte param, uint32 *cond_val)
{
        /* First handle variable common with VarAction2 */
        uint32 value;
        if (GetGlobalVariable(param - 0x80, &value, _cur.grffile)) return value;

        /* Non-common variable */
        switch (param) {
                case 0x84: { // GRF loading stage
                        uint32 res = 0;

                        if (_cur.stage > GLS_INIT) SetBit(res, 0);
                        if (_cur.stage == GLS_RESERVE) SetBit(res, 8);
                        if (_cur.stage == GLS_ACTIVATION) SetBit(res, 9);
                        return res;
                }

                case 0x85: // TTDPatch flags, only for bit tests
                        if (cond_val == nullptr) {
                                /* Supported in Action 0x07 and 0x09, not 0x0D */
                                return 0;
                        } else {
                                uint32 param_val = _ttdpatch_flags[*cond_val / 0x20];
                                *cond_val %= 0x20;
                                return param_val;
                        }

                case 0x88: // GRF ID check
                        return 0;

                /* case 0x99: Global ID offset not implemented */

                default:
                        /* GRF Parameter */
                        if (param < 0x80) return _cur.grffile->GetParam(param);

                        /* In-game variable. */
                        grfmsg(1, "Unsupported in-game variable 0x%02X", param);
                        return UINT_MAX;
        }
}

/* Action 0x06 */
static void CfgApply(ByteReader *buf)
{
        /* <06> <param-num> <param-size> <offset> ... <FF>
         *
         * B param-num     Number of parameter to substitute (First = "zero")
         *                 Ignored if that parameter was not specified in newgrf.cfg
         * B param-size    How many bytes to replace.  If larger than 4, the
         *                 bytes of the following parameter are used.  In that
         *                 case, nothing is applied unless *all* parameters
         *                 were specified.
         * B offset        Offset into data from beginning of next sprite
         *                 to place where parameter is to be stored. */

        /* Preload the next sprite */
        size_t pos = FioGetPos();
        uint32 num = _cur.grf_container_ver >= 2 ? FioReadDword() : FioReadWord();
        uint8 type = FioReadByte();
        byte *preload_sprite = nullptr;

        /* Check if the sprite is a pseudo sprite. We can't operate on real sprites. */
        if (type == 0xFF) {
                preload_sprite = MallocT<byte>(num);
                FioReadBlock(preload_sprite, num);
        }

        /* Reset the file position to the start of the next sprite */
        FioSeekTo(pos, SEEK_SET);

        if (type != 0xFF) {
                grfmsg(2, "CfgApply: Ignoring (next sprite is real, unsupported)");
                free(preload_sprite);
                return;
        }

        GRFLocation location(_cur.grfconfig->ident.grfid, _cur.nfo_line + 1);
        GRFLineToSpriteOverride::iterator it = _grf_line_to_action6_sprite_override.find(location);
        if (it != _grf_line_to_action6_sprite_override.end()) {
                free(preload_sprite);
                preload_sprite = it->second;
        } else {
                _grf_line_to_action6_sprite_override[location] = preload_sprite;
        }

        /* Now perform the Action 0x06 on our data. */

        for (;;) {
                uint i;
                uint param_num;
                uint param_size;
                uint offset;
                bool add_value;

                /* Read the parameter to apply. 0xFF indicates no more data to change. */
                param_num = buf->ReadByte();
                if (param_num == 0xFF) break;

                /* Get the size of the parameter to use. If the size covers multiple
                 * double words, sequential parameter values are used. */
                param_size = buf->ReadByte();

                /* Bit 7 of param_size indicates we should add to the original value
                 * instead of replacing it. */
                add_value  = HasBit(param_size, 7);
                param_size = GB(param_size, 0, 7);

                /* Where to apply the data to within the pseudo sprite data. */
                offset     = buf->ReadExtendedByte();

                /* If the parameter is a GRF parameter (not an internal variable) check
                 * if it (and all further sequential parameters) has been defined. */
                if (param_num < 0x80 && (param_num + (param_size - 1) / 4) >= _cur.grffile->param_end) {
                        grfmsg(2, "CfgApply: Ignoring (param %d not set)", (param_num + (param_size - 1) / 4));
                        break;
                }

                grfmsg(8, "CfgApply: Applying %u bytes from parameter 0x%02X at offset 0x%04X", param_size, param_num, offset);

                bool carry = false;
                for (i = 0; i < param_size && offset + i < num; i++) {
                        uint32 value = GetParamVal(param_num + i / 4, nullptr);
                        /* Reset carry flag for each iteration of the variable (only really
                         * matters if param_size is greater than 4) */
                        if (i % 4 == 0) carry = false;

                        if (add_value) {
                                uint new_value = preload_sprite[offset + i] + GB(value, (i % 4) * 8, 8) + (carry ? 1 : 0);
                                preload_sprite[offset + i] = GB(new_value, 0, 8);
                                /* Check if the addition overflowed */
                                carry = new_value >= 256;
                        } else {
                                preload_sprite[offset + i] = GB(value, (i % 4) * 8, 8);
                        }
                }
        }
}

/**
 * Disable a static NewGRF when it is influencing another (non-static)
 * NewGRF as this could cause desyncs.
 *
 * We could just tell the NewGRF querying that the file doesn't exist,
 * but that might give unwanted results. Disabling the NewGRF gives the
 * best result as no NewGRF author can complain about that.
 * @param c The NewGRF to disable.
 */
static void DisableStaticNewGRFInfluencingNonStaticNewGRFs(GRFConfig *c)
{
        GRFError *error = DisableGrf(STR_NEWGRF_ERROR_STATIC_GRF_CAUSES_DESYNC, c);
        error->data = stredup(_cur.grfconfig->GetName());
}

/* Action 0x07
 * Action 0x09 */
static void SkipIf(ByteReader *buf)
{
        /* <07/09> <param-num> <param-size> <condition-type> <value> <num-sprites>
         *
         * B param-num
         * B param-size
         * B condition-type
         * V value
         * B num-sprites */
        /* TODO: More params. More condition types. */
        uint32 cond_val = 0;
        uint32 mask = 0;
        bool result;

        uint8 param     = buf->ReadByte();
        uint8 paramsize = buf->ReadByte();
        uint8 condtype  = buf->ReadByte();

        if (condtype < 2) {
                /* Always 1 for bit tests, the given value should be ignored. */
                paramsize = 1;
        }

        switch (paramsize) {
                case 8: cond_val = buf->ReadDWord(); mask = buf->ReadDWord(); break;
                case 4: cond_val = buf->ReadDWord(); mask = 0xFFFFFFFF; break;
                case 2: cond_val = buf->ReadWord();  mask = 0x0000FFFF; break;
                case 1: cond_val = buf->ReadByte();  mask = 0x000000FF; break;
                default: break;
        }

        if (param < 0x80 && _cur.grffile->param_end <= param) {
                grfmsg(7, "SkipIf: Param %d undefined, skipping test", param);
                return;
        }

        uint32 param_val = GetParamVal(param, &cond_val);

        grfmsg(7, "SkipIf: Test condtype %d, param 0x%08X, condval 0x%08X", condtype, param_val, cond_val);

        /*
         * Parameter (variable in specs) 0x88 can only have GRF ID checking
         * conditions, except conditions 0x0B, 0x0C (cargo availability) and
         * 0x0D, 0x0E (Rail type availability) as those ignore the parameter.
         * So, when the condition type is one of those, the specific variable
         * 0x88 code is skipped, so the "general" code for the cargo
         * availability conditions kicks in.
         */
        if (param == 0x88 && (condtype < 0x0B || condtype > 0x0E)) {
                /* GRF ID checks */

                GRFConfig *c = GetGRFConfig(cond_val, mask);

                if (c != nullptr && HasBit(c->flags, GCF_STATIC) && !HasBit(_cur.grfconfig->flags, GCF_STATIC) && _networking) {
                        DisableStaticNewGRFInfluencingNonStaticNewGRFs(c);
                        c = nullptr;
                }

                if (condtype != 10 && c == nullptr) {
                        grfmsg(7, "SkipIf: GRFID 0x%08X unknown, skipping test", BSWAP32(cond_val));
                        return;
                }

                switch (condtype) {
                        /* Tests 0x06 to 0x0A are only for param 0x88, GRFID checks */
                        case 0x06: // Is GRFID active?
                                result = c->status == GCS_ACTIVATED;
                                break;

                        case 0x07: // Is GRFID non-active?
                                result = c->status != GCS_ACTIVATED;
                                break;

                        case 0x08: // GRFID is not but will be active?
                                result = c->status == GCS_INITIALISED;
                                break;

                        case 0x09: // GRFID is or will be active?
                                result = c->status == GCS_ACTIVATED || c->status == GCS_INITIALISED;
                                break;

                        case 0x0A: // GRFID is not nor will be active
                                /* This is the only condtype that doesn't get ignored if the GRFID is not found */
                                result = c == nullptr || c->status == GCS_DISABLED || c->status == GCS_NOT_FOUND;
                                break;

                        default: grfmsg(1, "SkipIf: Unsupported GRF condition type %02X. Ignoring", condtype); return;
                }
        } else {
                /* Parameter or variable tests */
                switch (condtype) {
                        case 0x00: result = !!(param_val & (1 << cond_val));
                                break;
                        case 0x01: result = !(param_val & (1 << cond_val));
                                break;
                        case 0x02: result = (param_val & mask) == cond_val;
                                break;
                        case 0x03: result = (param_val & mask) != cond_val;
                                break;
                        case 0x04: result = (param_val & mask) < cond_val;
                                break;
                        case 0x05: result = (param_val & mask) > cond_val;
                                break;
                        case 0x0B: result = GetCargoIDByLabel(BSWAP32(cond_val)) == CT_INVALID;
                                break;
                        case 0x0C: result = GetCargoIDByLabel(BSWAP32(cond_val)) != CT_INVALID;
                                break;
                        case 0x0D: result = GetRailTypeByLabel(BSWAP32(cond_val)) == INVALID_RAILTYPE;
                                break;
                        case 0x0E: result = GetRailTypeByLabel(BSWAP32(cond_val)) != INVALID_RAILTYPE;
                                break;
                        case 0x0F: result = !GetRoadTypeByLabel(BSWAP32(cond_val), ROADTYPE_ROAD).IsValid();
                                break;
                        case 0x10: result = GetRoadTypeByLabel(BSWAP32(cond_val), ROADTYPE_ROAD).IsValid();
                                break;
                        case 0x11: result = !GetRoadTypeByLabel(BSWAP32(cond_val), ROADTYPE_TRAM).IsValid();
                                break;
                        case 0x12: result = GetRoadTypeByLabel(BSWAP32(cond_val), ROADTYPE_TRAM).IsValid();
                                break;

                        default: grfmsg(1, "SkipIf: Unsupported condition type %02X. Ignoring", condtype); return;
                }
        }

        if (!result) {
                grfmsg(2, "SkipIf: Not skipping sprites, test was false");
                return;
        }

        uint8 numsprites = buf->ReadByte();

        /* numsprites can be a GOTO label if it has been defined in the GRF
         * file. The jump will always be the first matching label that follows
         * the current nfo_line. If no matching label is found, the first matching
         * label in the file is used. */
        GRFLabel *choice = nullptr;
        for (GRFLabel *label = _cur.grffile->label; label != nullptr; label = label->next) {
                if (label->label != numsprites) continue;

                /* Remember a goto before the current line */
                if (choice == nullptr) choice = label;
                /* If we find a label here, this is definitely good */
                if (label->nfo_line > _cur.nfo_line) {
                        choice = label;
                        break;
                }
        }

        if (choice != nullptr) {
                grfmsg(2, "SkipIf: Jumping to label 0x%0X at line %d, test was true", choice->label, choice->nfo_line);
                FioSeekTo(choice->pos, SEEK_SET);
                _cur.nfo_line = choice->nfo_line;
                return;
        }

        grfmsg(2, "SkipIf: Skipping %d sprites, test was true", numsprites);
        _cur.skip_sprites = numsprites;
        if (_cur.skip_sprites == 0) {
                /* Zero means there are no sprites to skip, so
                 * we use -1 to indicate that all further
                 * sprites should be skipped. */
                _cur.skip_sprites = -1;

                /* If an action 8 hasn't been encountered yet, disable the grf. */
                if (_cur.grfconfig->status != (_cur.stage < GLS_RESERVE ? GCS_INITIALISED : GCS_ACTIVATED)) {
                        DisableGrf();
                }
        }
}


/* Action 0x08 (GLS_FILESCAN) */
static void ScanInfo(ByteReader *buf)
{
        uint8 grf_version = buf->ReadByte();
        uint32 grfid      = buf->ReadDWord();
        const char *name  = buf->ReadString();

        _cur.grfconfig->ident.grfid = grfid;

        if (grf_version < 2 || grf_version > 8) {
                SetBit(_cur.grfconfig->flags, GCF_INVALID);
                DEBUG(grf, 0, "%s: NewGRF \"%s\" (GRFID %08X) uses GRF version %d, which is incompatible with this version of OpenTTD.", _cur.grfconfig->filename, name, BSWAP32(grfid), grf_version);
        }

        /* GRF IDs starting with 0xFF are reserved for internal TTDPatch use */
        if (GB(grfid, 0, 8) == 0xFF) SetBit(_cur.grfconfig->flags, GCF_SYSTEM);

        AddGRFTextToList(&_cur.grfconfig->name->text, 0x7F, grfid, false, name);

        if (buf->HasData()) {
                const char *info = buf->ReadString();
                AddGRFTextToList(&_cur.grfconfig->info->text, 0x7F, grfid, true, info);
        }

        /* GLS_INFOSCAN only looks for the action 8, so we can skip the rest of the file */
        _cur.skip_sprites = -1;
}

/* Action 0x08 */
static void GRFInfo(ByteReader *buf)
{
        /* <08> <version> <grf-id> <name> <info>
         *
         * B version       newgrf version, currently 06
         * 4*B grf-id      globally unique ID of this .grf file
         * S name          name of this .grf set
         * S info          string describing the set, and e.g. author and copyright */

        uint8 version    = buf->ReadByte();
        uint32 grfid     = buf->ReadDWord();
        const char *name = buf->ReadString();

        if (_cur.stage < GLS_RESERVE && _cur.grfconfig->status != GCS_UNKNOWN) {
                DisableGrf(STR_NEWGRF_ERROR_MULTIPLE_ACTION_8);
                return;
        }

        if (_cur.grffile->grfid != grfid) {
                DEBUG(grf, 0, "GRFInfo: GRFID %08X in FILESCAN stage does not match GRFID %08X in INIT/RESERVE/ACTIVATION stage", BSWAP32(_cur.grffile->grfid), BSWAP32(grfid));
                _cur.grffile->grfid = grfid;
        }

        _cur.grffile->grf_version = version;
        _cur.grfconfig->status = _cur.stage < GLS_RESERVE ? GCS_INITIALISED : GCS_ACTIVATED;

        /* Do swap the GRFID for displaying purposes since people expect that */
        DEBUG(grf, 1, "GRFInfo: Loaded GRFv%d set %08X - %s (palette: %s, version: %i)", version, BSWAP32(grfid), name, (_cur.grfconfig->palette & GRFP_USE_MASK) ? "Windows" : "DOS", _cur.grfconfig->version);
}

/* Action 0x0A */
static void SpriteReplace(ByteReader *buf)
{
        /* <0A> <num-sets> <set1> [<set2> ...]
         * <set>: <num-sprites> <first-sprite>
         *
         * B num-sets      How many sets of sprites to replace.
         * Each set:
         * B num-sprites   How many sprites are in this set
         * W first-sprite  First sprite number to replace */

        uint8 num_sets = buf->ReadByte();

        for (uint i = 0; i < num_sets; i++) {
                uint8 num_sprites = buf->ReadByte();
                uint16 first_sprite = buf->ReadWord();

                grfmsg(2, "SpriteReplace: [Set %d] Changing %d sprites, beginning with %d",
                        i, num_sprites, first_sprite
                );

                for (uint j = 0; j < num_sprites; j++) {
                        int load_index = first_sprite + j;
                        _cur.nfo_line++;
                        LoadNextSprite(load_index, _cur.file_index, _cur.nfo_line, _cur.grf_container_ver); // XXX

                        /* Shore sprites now located at different addresses.
                         * So detect when the old ones get replaced. */
                        if (IsInsideMM(load_index, SPR_ORIGINALSHORE_START, SPR_ORIGINALSHORE_END + 1)) {
                                if (_loaded_newgrf_features.shore != SHORE_REPLACE_ACTION_5) _loaded_newgrf_features.shore = SHORE_REPLACE_ACTION_A;
                        }
                }
        }
}

/* Action 0x0A (SKIP) */
static void SkipActA(ByteReader *buf)
{
        uint8 num_sets = buf->ReadByte();

        for (uint i = 0; i < num_sets; i++) {
                /* Skip the sprites this replaces */
                _cur.skip_sprites += buf->ReadByte();
                /* But ignore where they go */
                buf->ReadWord();
        }

        grfmsg(3, "SkipActA: Skipping %d sprites", _cur.skip_sprites);
}

/* Action 0x0B */
static void GRFLoadError(ByteReader *buf)
{
        /* <0B> <severity> <language-id> <message-id> [<message...> 00] [<data...>] 00 [<parnum>]
         *
         * B severity      00: notice, contine loading grf file
         *                 01: warning, continue loading grf file
         *                 02: error, but continue loading grf file, and attempt
         *                     loading grf again when loading or starting next game
         *                 03: error, abort loading and prevent loading again in
         *                     the future (only when restarting the patch)
         * B language-id   see action 4, use 1F for built-in error messages
         * B message-id    message to show, see below
         * S message       for custom messages (message-id FF), text of the message
         *                 not present for built-in messages.
         * V data          additional data for built-in (or custom) messages
         * B parnum        parameter numbers to be shown in the message (maximum of 2) */

        static const StringID msgstr[] = {
                STR_NEWGRF_ERROR_VERSION_NUMBER,
                STR_NEWGRF_ERROR_DOS_OR_WINDOWS,
                STR_NEWGRF_ERROR_UNSET_SWITCH,
                STR_NEWGRF_ERROR_INVALID_PARAMETER,
                STR_NEWGRF_ERROR_LOAD_BEFORE,
                STR_NEWGRF_ERROR_LOAD_AFTER,
                STR_NEWGRF_ERROR_OTTD_VERSION_NUMBER,
        };

        static const StringID sevstr[] = {
                STR_NEWGRF_ERROR_MSG_INFO,
                STR_NEWGRF_ERROR_MSG_WARNING,
                STR_NEWGRF_ERROR_MSG_ERROR,
                STR_NEWGRF_ERROR_MSG_FATAL
        };

        byte severity   = buf->ReadByte();
        byte lang       = buf->ReadByte();
        byte message_id = buf->ReadByte();

        /* Skip the error if it isn't valid for the current language. */
        if (!CheckGrfLangID(lang, _cur.grffile->grf_version)) return;

        /* Skip the error until the activation stage unless bit 7 of the severity
         * is set. */
        if (!HasBit(severity, 7) && _cur.stage == GLS_INIT) {
                grfmsg(7, "GRFLoadError: Skipping non-fatal GRFLoadError in stage %d", _cur.stage);
                return;
        }
        ClrBit(severity, 7);

        if (severity >= lengthof(sevstr)) {
                grfmsg(7, "GRFLoadError: Invalid severity id %d. Setting to 2 (non-fatal error).", severity);
                severity = 2;
        } else if (severity == 3) {
                /* This is a fatal error, so make sure the GRF is deactivated and no
                 * more of it gets loaded. */
                DisableGrf();

                /* Make sure we show fatal errors, instead of silly infos from before */
                delete _cur.grfconfig->error;
                _cur.grfconfig->error = nullptr;
        }

        if (message_id >= lengthof(msgstr) && message_id != 0xFF) {
                grfmsg(7, "GRFLoadError: Invalid message id.");
                return;
        }

        if (buf->Remaining() <= 1) {
                grfmsg(7, "GRFLoadError: No message data supplied.");
                return;
        }

        /* For now we can only show one message per newgrf file. */
        if (_cur.grfconfig->error != nullptr) return;

        GRFError *error = new GRFError(sevstr[severity]);

        if (message_id == 0xFF) {
                /* This is a custom error message. */
                if (buf->HasData()) {
                        const char *message = buf->ReadString();

                        error->custom_message = TranslateTTDPatchCodes(_cur.grffile->grfid, lang, true, message, nullptr, SCC_RAW_STRING_POINTER);
                } else {
                        grfmsg(7, "GRFLoadError: No custom message supplied.");
                        error->custom_message = stredup("");
                }
        } else {
                error->message = msgstr[message_id];
        }

        if (buf->HasData()) {
                const char *data = buf->ReadString();

                error->data = TranslateTTDPatchCodes(_cur.grffile->grfid, lang, true, data);
        } else {
                grfmsg(7, "GRFLoadError: No message data supplied.");
                error->data = stredup("");
        }

        /* Only two parameter numbers can be used in the string. */
        for (uint i = 0; i < lengthof(error->param_value) && buf->HasData(); i++) {
                uint param_number = buf->ReadByte();
                error->param_value[i] = _cur.grffile->GetParam(param_number);
        }

        _cur.grfconfig->error = error;
}

/* Action 0x0C */
static void GRFComment(ByteReader *buf)
{
        /* <0C> [<ignored...>]
         *
         * V ignored       Anything following the 0C is ignored */

        if (!buf->HasData()) return;

        const char *text = buf->ReadString();
        grfmsg(2, "GRFComment: %s", text);
}

/* Action 0x0D (GLS_SAFETYSCAN) */
static void SafeParamSet(ByteReader *buf)
{
        uint8 target = buf->ReadByte();

        /* Writing GRF parameters and some bits of 'misc GRF features' are safe. */
        if (target < 0x80 || target == 0x9E) return;

        /* GRM could be unsafe, but as here it can only happen after other GRFs
         * are loaded, it should be okay. If the GRF tried to use the slots it
         * reserved, it would be marked unsafe anyway. GRM for (e.g. bridge)
         * sprites  is considered safe. */

        SetBit(_cur.grfconfig->flags, GCF_UNSAFE);

        /* Skip remainder of GRF */
        _cur.skip_sprites = -1;
}


static uint32 GetPatchVariable(uint8 param)
{
        switch (param) {
                /* start year - 1920 */
                case 0x0B: return max(_settings_game.game_creation.starting_year, ORIGINAL_BASE_YEAR) - ORIGINAL_BASE_YEAR;

                /* freight trains weight factor */
                case 0x0E: return _settings_game.vehicle.freight_trains;

                /* empty wagon speed increase */
                case 0x0F: return 0;

                /* plane speed factor; our patch option is reversed from TTDPatch's,
                 * the following is good for 1x, 2x and 4x (most common?) and...
                 * well not really for 3x. */
                case 0x10:
                        switch (_settings_game.vehicle.plane_speed) {
                                default:
                                case 4: return 1;
                                case 3: return 2;
                                case 2: return 2;
                                case 1: return 4;
                        }


                /* 2CC colourmap base sprite */
                case 0x11: return SPR_2CCMAP_BASE;

                /* map size: format = -MABXYSS
                 * M  : the type of map
                 *       bit 0 : set   : squared map. Bit 1 is now not relevant
                 *               clear : rectangle map. Bit 1 will indicate the bigger edge of the map
                 *       bit 1 : set   : Y is the bigger edge. Bit 0 is clear
                 *               clear : X is the bigger edge.
                 * A  : minimum edge(log2) of the map
                 * B  : maximum edge(log2) of the map
                 * XY : edges(log2) of each side of the map.
                 * SS : combination of both X and Y, thus giving the size(log2) of the map
                 */
                case 0x13: {
                        byte map_bits = 0;
                        byte log_X = MapLogX() - 6; // substraction is required to make the minimal size (64) zero based
                        byte log_Y = MapLogY() - 6;
                        byte max_edge = max(log_X, log_Y);

                        if (log_X == log_Y) { // we have a squared map, since both edges are identical
                                SetBit(map_bits, 0);
                        } else {
                                if (max_edge == log_Y) SetBit(map_bits, 1); // edge Y been the biggest, mark it
                        }

                        return (map_bits << 24) | (min(log_X, log_Y) << 20) | (max_edge << 16) |
                                (log_X << 12) | (log_Y << 8) | (log_X + log_Y);
                }

                /* The maximum height of the map. */
                case 0x14:
                        return _settings_game.construction.max_heightlevel;

                /* Extra foundations base sprite */
                case 0x15:
                        return SPR_SLOPES_BASE;

                /* Shore base sprite */
                case 0x16:
                        return SPR_SHORE_BASE;

                default:
                        grfmsg(2, "ParamSet: Unknown Patch variable 0x%02X.", param);
                        return 0;
        }
}


static uint32 PerformGRM(uint32 *grm, uint16 num_ids, uint16 count, uint8 op, uint8 target, const char *type)
{
        uint start = 0;
        uint size  = 0;

        if (op == 6) {
                /* Return GRFID of set that reserved ID */
                return grm[_cur.grffile->GetParam(target)];
        }

        /* With an operation of 2 or 3, we want to reserve a specific block of IDs */
        if (op == 2 || op == 3) start = _cur.grffile->GetParam(target);

        for (uint i = start; i < num_ids; i++) {
                if (grm[i] == 0) {
                        size++;
                } else {
                        if (op == 2 || op == 3) break;
                        start = i + 1;
                        size = 0;
                }

                if (size == count) break;
        }

        if (size == count) {
                /* Got the slot... */
                if (op == 0 || op == 3) {
                        grfmsg(2, "ParamSet: GRM: Reserving %d %s at %d", count, type, start);
                        for (uint i = 0; i < count; i++) grm[start + i] = _cur.grffile->grfid;
                }
                return start;
        }

        /* Unable to allocate */
        if (op != 4 && op != 5) {
                /* Deactivate GRF */
                grfmsg(0, "ParamSet: GRM: Unable to allocate %d %s, deactivating", count, type);
                DisableGrf(STR_NEWGRF_ERROR_GRM_FAILED);
                return UINT_MAX;
        }

        grfmsg(1, "ParamSet: GRM: Unable to allocate %d %s", count, type);
        return UINT_MAX;
}


/** Action 0x0D: Set parameter */
static void ParamSet(ByteReader *buf)
{
        /* <0D> <target> <operation> <source1> <source2> [<data>]
         *
         * B target        parameter number where result is stored
         * B operation     operation to perform, see below
         * B source1       first source operand
         * B source2       second source operand
         * D data          data to use in the calculation, not necessary
         *                 if both source1 and source2 refer to actual parameters
         *
         * Operations
         * 00      Set parameter equal to source1
         * 01      Addition, source1 + source2
         * 02      Subtraction, source1 - source2
         * 03      Unsigned multiplication, source1 * source2 (both unsigned)
         * 04      Signed multiplication, source1 * source2 (both signed)
         * 05      Unsigned bit shift, source1 by source2 (source2 taken to be a
         *         signed quantity; left shift if positive and right shift if
         *         negative, source1 is unsigned)
         * 06      Signed bit shift, source1 by source2
         *         (source2 like in 05, and source1 as well)
         */

        uint8 target = buf->ReadByte();
        uint8 oper   = buf->ReadByte();
        uint32 src1  = buf->ReadByte();
        uint32 src2  = buf->ReadByte();

        uint32 data = 0;
        if (buf->Remaining() >= 4) data = buf->ReadDWord();

        /* You can add 80 to the operation to make it apply only if the target
         * is not defined yet.  In this respect, a parameter is taken to be
         * defined if any of the following applies:
         * - it has been set to any value in the newgrf(w).cfg parameter list
         * - it OR A PARAMETER WITH HIGHER NUMBER has been set to any value by
         *   an earlier action D */
        if (HasBit(oper, 7)) {
                if (target < 0x80 && target < _cur.grffile->param_end) {
                        grfmsg(7, "ParamSet: Param %u already defined, skipping", target);
                        return;
                }

                oper = GB(oper, 0, 7);
        }

        if (src2 == 0xFE) {
                if (GB(data, 0, 8) == 0xFF) {
                        if (data == 0x0000FFFF) {
                                /* Patch variables */
                                src1 = GetPatchVariable(src1);
                        } else {
                                /* GRF Resource Management */
                                uint8  op      = src1;
                                uint8  feature = GB(data, 8, 8);
                                uint16 count   = GB(data, 16, 16);

                                if (_cur.stage == GLS_RESERVE) {
                                        if (feature == 0x08) {
                                                /* General sprites */
                                                if (op == 0) {
                                                        /* Check if the allocated sprites will fit below the original sprite limit */
                                                        if (_cur.spriteid + count >= 16384) {
                                                                grfmsg(0, "ParamSet: GRM: Unable to allocate %d sprites; try changing NewGRF order", count);
                                                                DisableGrf(STR_NEWGRF_ERROR_GRM_FAILED);
                                                                return;
                                                        }

                                                        /* Reserve space at the current sprite ID */
                                                        grfmsg(4, "ParamSet: GRM: Allocated %d sprites at %d", count, _cur.spriteid);
                                                        _grm_sprites[GRFLocation(_cur.grffile->grfid, _cur.nfo_line)] = _cur.spriteid;
                                                        _cur.spriteid += count;
                                                }
                                        }
                                        /* Ignore GRM result during reservation */
                                        src1 = 0;
                                } else if (_cur.stage == GLS_ACTIVATION) {
                                        switch (feature) {
                                                case 0x00: // Trains
                                                case 0x01: // Road Vehicles
                                                case 0x02: // Ships
                                                case 0x03: // Aircraft
                                                        if (!_settings_game.vehicle.dynamic_engines) {
                                                                src1 = PerformGRM(&_grm_engines[_engine_offsets[feature]], _engine_counts[feature], count, op, target, "vehicles");
                                                                if (_cur.skip_sprites == -1) return;
                                                        } else {
                                                                /* GRM does not apply for dynamic engine allocation. */
                                                                switch (op) {
                                                                        case 2:
                                                                        case 3:
                                                                                src1 = _cur.grffile->GetParam(target);
                                                                                break;

                                                                        default:
                                                                                src1 = 0;
                                                                                break;
                                                                }
                                                        }
                                                        break;

                                                case 0x08: // General sprites
                                                        switch (op) {
                                                                case 0:
                                                                        /* Return space reserved during reservation stage */
                                                                        src1 = _grm_sprites[GRFLocation(_cur.grffile->grfid, _cur.nfo_line)];
                                                                        grfmsg(4, "ParamSet: GRM: Using pre-allocated sprites at %d", src1);
                                                                        break;

                                                                case 1:
                                                                        src1 = _cur.spriteid;
                                                                        break;

                                                                default:
                                                                        grfmsg(1, "ParamSet: GRM: Unsupported operation %d for general sprites", op);
                                                                        return;
                                                        }
                                                        break;

                                                case 0x0B: // Cargo
                                                        /* There are two ranges: one for cargo IDs and one for cargo bitmasks */
                                                        src1 = PerformGRM(_grm_cargoes, NUM_CARGO * 2, count, op, target, "cargoes");
                                                        if (_cur.skip_sprites == -1) return;
                                                        break;

                                                default: grfmsg(1, "ParamSet: GRM: Unsupported feature 0x%X", feature); return;
                                        }
                                } else {
                                        /* Ignore GRM during initialization */
                                        src1 = 0;
                                }
                        }
                } else {
                        /* Read another GRF File's parameter */
                        const GRFFile *file = GetFileByGRFID(data);
                        GRFConfig *c = GetGRFConfig(data);
                        if (c != nullptr && HasBit(c->flags, GCF_STATIC) && !HasBit(_cur.grfconfig->flags, GCF_STATIC) && _networking) {
                                /* Disable the read GRF if it is a static NewGRF. */
                                DisableStaticNewGRFInfluencingNonStaticNewGRFs(c);
                                src1 = 0;
                        } else if (file == nullptr || c == nullptr || c->status == GCS_DISABLED) {
                                src1 = 0;
                        } else if (src1 == 0xFE) {
                                src1 = c->version;
                        } else {
                                src1 = file->GetParam(src1);
                        }
                }
        } else {
                /* The source1 and source2 operands refer to the grf parameter number
                 * like in action 6 and 7.  In addition, they can refer to the special
                 * variables available in action 7, or they can be FF to use the value
                 * of <data>.  If referring to parameters that are undefined, a value
                 * of 0 is used instead.  */
                src1 = (src1 == 0xFF) ? data : GetParamVal(src1, nullptr);
                src2 = (src2 == 0xFF) ? data : GetParamVal(src2, nullptr);
        }

        /* TODO: You can access the parameters of another GRF file by using
         * source2=FE, source1=the other GRF's parameter number and data=GRF
         * ID.  This is only valid with operation 00 (set).  If the GRF ID
         * cannot be found, a value of 0 is used for the parameter value
         * instead. */

        uint32 res;
        switch (oper) {
                case 0x00:
                        res = src1;
                        break;

                case 0x01:
                        res = src1 + src2;
                        break;

                case 0x02:
                        res = src1 - src2;
                        break;

                case 0x03:
                        res = src1 * src2;
                        break;

                case 0x04:
                        res = (int32)src1 * (int32)src2;
                        break;

                case 0x05:
                        if ((int32)src2 < 0) {
                                res = src1 >> -(int32)src2;
                        } else {
                                res = src1 << (src2 & 0x1F); // Same behaviour as in EvalAdjustT, mask 'value' to 5 bits, which should behave the same on all architectures.
                        }
                        break;

                case 0x06:
                        if ((int32)src2 < 0) {
                                res = (int32)src1 >> -(int32)src2;
                        } else {
                                res = (int32)src1 << (src2 & 0x1F); // Same behaviour as in EvalAdjustT, mask 'value' to 5 bits, which should behave the same on all architectures.
                        }
                        break;

                case 0x07: // Bitwise AND
                        res = src1 & src2;
                        break;

                case 0x08: // Bitwise OR
                        res = src1 | src2;
                        break;

                case 0x09: // Unsigned division
                        if (src2 == 0) {
                                res = src1;
                        } else {
                                res = src1 / src2;
                        }
                        break;

                case 0x0A: // Signed divison
                        if (src2 == 0) {
                                res = src1;
                        } else {
                                res = (int32)src1 / (int32)src2;
                        }
                        break;

                case 0x0B: // Unsigned modulo
                        if (src2 == 0) {
                                res = src1;
                        } else {
                                res = src1 % src2;
                        }
                        break;

                case 0x0C: // Signed modulo
                        if (src2 == 0) {
                                res = src1;
                        } else {
                                res = (int32)src1 % (int32)src2;
                        }
                        break;

                default: grfmsg(0, "ParamSet: Unknown operation %d, skipping", oper); return;
        }

        switch (target) {
                case 0x8E: // Y-Offset for train sprites
                        _cur.grffile->traininfo_vehicle_pitch = res;
                        break;

                case 0x8F: { // Rail track type cost factors
                        extern RailtypeInfo _railtypes[RAILTYPE_END];
                        _railtypes[RAILTYPE_RAIL].cost_multiplier = GB(res, 0, 8);
                        if (_settings_game.vehicle.disable_elrails) {
                                _railtypes[RAILTYPE_ELECTRIC].cost_multiplier = GB(res, 0, 8);
                                _railtypes[RAILTYPE_MONO].cost_multiplier = GB(res, 8, 8);
                        } else {
                                _railtypes[RAILTYPE_ELECTRIC].cost_multiplier = GB(res, 8, 8);
                                _railtypes[RAILTYPE_MONO].cost_multiplier = GB(res, 16, 8);
                        }
                        _railtypes[RAILTYPE_MAGLEV].cost_multiplier = GB(res, 16, 8);
                        break;
                }

                /* @todo implement */
                case 0x93: // Tile refresh offset to left
                case 0x94: // Tile refresh offset to right
                case 0x95: // Tile refresh offset upwards
                case 0x96: // Tile refresh offset downwards
                case 0x97: // Snow line height
                case 0x99: // Global ID offset
                        grfmsg(7, "ParamSet: Skipping unimplemented target 0x%02X", target);
                        break;

                case 0x9E: // Miscellaneous GRF features
                        /* Set train list engine width */
                        _cur.grffile->traininfo_vehicle_width = HasBit(res, GMB_TRAIN_WIDTH_32_PIXELS) ? VEHICLEINFO_FULL_VEHICLE_WIDTH : TRAININFO_DEFAULT_VEHICLE_WIDTH;
                        /* Remove the local flags from the global flags */
                        ClrBit(res, GMB_TRAIN_WIDTH_32_PIXELS);

                        /* Only copy safe bits for static grfs */
                        if (HasBit(_cur.grfconfig->flags, GCF_STATIC)) {
                                uint32 safe_bits = 0;
                                SetBit(safe_bits, GMB_SECOND_ROCKY_TILE_SET);

                                _misc_grf_features = (_misc_grf_features & ~safe_bits) | (res & safe_bits);
                        } else {
                                _misc_grf_features = res;
                        }
                        break;

                case 0x9F: // locale-dependent settings
                        grfmsg(7, "ParamSet: Skipping unimplemented target 0x%02X", target);
                        break;

                default:
                        if (target < 0x80) {
                                _cur.grffile->param[target] = res;
                                /* param is zeroed by default */
                                if (target + 1U > _cur.grffile->param_end) _cur.grffile->param_end = target + 1;
                        } else {
                                grfmsg(7, "ParamSet: Skipping unknown target 0x%02X", target);
                        }
                        break;
        }
}

/* Action 0x0E (GLS_SAFETYSCAN) */
static void SafeGRFInhibit(ByteReader *buf)
{
        /* <0E> <num> <grfids...>
         *
         * B num           Number of GRFIDs that follow
         * D grfids        GRFIDs of the files to deactivate */

        uint8 num = buf->ReadByte();

        for (uint i = 0; i < num; i++) {
                uint32 grfid = buf->ReadDWord();

                /* GRF is unsafe it if tries to deactivate other GRFs */
                if (grfid != _cur.grfconfig->ident.grfid) {
                        SetBit(_cur.grfconfig->flags, GCF_UNSAFE);

                        /* Skip remainder of GRF */
                        _cur.skip_sprites = -1;

                        return;
                }
        }
}

/* Action 0x0E */
static void GRFInhibit(ByteReader *buf)
{
        /* <0E> <num> <grfids...>
         *
         * B num           Number of GRFIDs that follow
         * D grfids        GRFIDs of the files to deactivate */

        uint8 num = buf->ReadByte();

        for (uint i = 0; i < num; i++) {
                uint32 grfid = buf->ReadDWord();
                GRFConfig *file = GetGRFConfig(grfid);

                /* Unset activation flag */
                if (file != nullptr && file != _cur.grfconfig) {
                        grfmsg(2, "GRFInhibit: Deactivating file '%s'", file->filename);
                        GRFError *error = DisableGrf(STR_NEWGRF_ERROR_FORCEFULLY_DISABLED, file);
                        error->data = stredup(_cur.grfconfig->GetName());
                }
        }
}

/** Action 0x0F - Define Town names */
static void FeatureTownName(ByteReader *buf)
{
        /* <0F> <id> <style-name> <num-parts> <parts>
         *
         * B id          ID of this definition in bottom 7 bits (final definition if bit 7 set)
         * V style-name  Name of the style (only for final definition)
         * B num-parts   Number of parts in this definition
         * V parts       The parts */

        uint32 grfid = _cur.grffile->grfid;

        GRFTownName *townname = AddGRFTownName(grfid);

        byte id = buf->ReadByte();
        grfmsg(6, "FeatureTownName: definition 0x%02X", id & 0x7F);

        if (HasBit(id, 7)) {
                /* Final definition */
                ClrBit(id, 7);
                bool new_scheme = _cur.grffile->grf_version >= 7;

                byte lang = buf->ReadByte();

                byte nb_gen = townname->nb_gen;
                do {
                        ClrBit(lang, 7);

                        const char *name = buf->ReadString();

                        char *lang_name = TranslateTTDPatchCodes(grfid, lang, false, name);
                        grfmsg(6, "FeatureTownName: lang 0x%X -> '%s'", lang, lang_name);
                        free(lang_name);

                        townname->name[nb_gen] = AddGRFString(grfid, id, lang, new_scheme, false, name, STR_UNDEFINED);

                        lang = buf->ReadByte();
                } while (lang != 0);
                townname->id[nb_gen] = id;
                townname->nb_gen++;
        }

        byte nb = buf->ReadByte();
        grfmsg(6, "FeatureTownName: %u parts", nb);

        townname->nbparts[id] = nb;
        townname->partlist[id] = CallocT<NamePartList>(nb);

        for (int i = 0; i < nb; i++) {
                byte nbtext =  buf->ReadByte();
                townname->partlist[id][i].bitstart  = buf->ReadByte();
                townname->partlist[id][i].bitcount  = buf->ReadByte();
                townname->partlist[id][i].maxprob   = 0;
                townname->partlist[id][i].partcount = nbtext;
                townname->partlist[id][i].parts     = CallocT<NamePart>(nbtext);
                grfmsg(6, "FeatureTownName: part %d contains %d texts and will use GB(seed, %d, %d)", i, nbtext, townname->partlist[id][i].bitstart, townname->partlist[id][i].bitcount);

                for (int j = 0; j < nbtext; j++) {
                        byte prob = buf->ReadByte();

                        if (HasBit(prob, 7)) {
                                byte ref_id = buf->ReadByte();

                                if (townname->nbparts[ref_id] == 0) {
                                        grfmsg(0, "FeatureTownName: definition 0x%02X doesn't exist, deactivating", ref_id);
                                        DelGRFTownName(grfid);
                                        DisableGrf(STR_NEWGRF_ERROR_INVALID_ID);
                                        return;
                                }

                                grfmsg(6, "FeatureTownName: part %d, text %d, uses intermediate definition 0x%02X (with probability %d)", i, j, ref_id, prob & 0x7F);
                                townname->partlist[id][i].parts[j].data.id = ref_id;
                        } else {
                                const char *text = buf->ReadString();
                                townname->partlist[id][i].parts[j].data.text = TranslateTTDPatchCodes(grfid, 0, false, text);
                                grfmsg(6, "FeatureTownName: part %d, text %d, '%s' (with probability %d)", i, j, townname->partlist[id][i].parts[j].data.text, prob);
                        }
                        townname->partlist[id][i].parts[j].prob = prob;
                        townname->partlist[id][i].maxprob += GB(prob, 0, 7);
                }
                grfmsg(6, "FeatureTownName: part %d, total probability %d", i, townname->partlist[id][i].maxprob);
        }
}

/** Action 0x10 - Define goto label */
static void DefineGotoLabel(ByteReader *buf)
{
        /* <10> <label> [<comment>]
         *
         * B label      The label to define
         * V comment    Optional comment - ignored */

        byte nfo_label = buf->ReadByte();

        GRFLabel *label = MallocT<GRFLabel>(1);
        label->label    = nfo_label;
        label->nfo_line = _cur.nfo_line;
        label->pos      = FioGetPos();
        label->next     = nullptr;

        /* Set up a linked list of goto targets which we will search in an Action 0x7/0x9 */
        if (_cur.grffile->label == nullptr) {
                _cur.grffile->label = label;
        } else {
                /* Attach the label to the end of the list */
                GRFLabel *l;
                for (l = _cur.grffile->label; l->next != nullptr; l = l->next) {}
                l->next = label;
        }

        grfmsg(2, "DefineGotoLabel: GOTO target with label 0x%02X", label->label);
}

/**
 * Process a sound import from another GRF file.
 * @param sound Destination for sound.
 */
static void ImportGRFSound(SoundEntry *sound)
{
        const GRFFile *file;
        uint32 grfid = FioReadDword();
        SoundID sound_id = FioReadWord();

        file = GetFileByGRFID(grfid);
        if (file == nullptr || file->sound_offset == 0) {
                grfmsg(1, "ImportGRFSound: Source file not available");
                return;
        }

        if (sound_id >= file->num_sounds) {
                grfmsg(1, "ImportGRFSound: Sound effect %d is invalid", sound_id);
                return;
        }

        grfmsg(2, "ImportGRFSound: Copying sound %d (%d) from file %X", sound_id, file->sound_offset + sound_id, grfid);

        *sound = *GetSound(file->sound_offset + sound_id);

        /* Reset volume and priority, which TTDPatch doesn't copy */
        sound->volume   = 128;
        sound->priority = 0;
}

/**
 * Load a sound from a file.
 * @param offs File offset to read sound from.
 * @param sound Destination for sound.
 */
static void LoadGRFSound(size_t offs, SoundEntry *sound)
{
        /* Set default volume and priority */
        sound->volume = 0x80;
        sound->priority = 0;

        if (offs != SIZE_MAX) {
                /* Sound is present in the NewGRF. */
                sound->file_slot = _cur.file_index;
                sound->file_offset = offs;
                sound->grf_container_ver = _cur.grf_container_ver;
        }
}

/* Action 0x11 */
static void GRFSound(ByteReader *buf)
{
        /* <11> <num>
         *
         * W num      Number of sound files that follow */

        uint16 num = buf->ReadWord();
        if (num == 0) return;

        SoundEntry *sound;
        if (_cur.grffile->sound_offset == 0) {
                _cur.grffile->sound_offset = GetNumSounds();
                _cur.grffile->num_sounds = num;
                sound = AllocateSound(num);
        } else {
                sound = GetSound(_cur.grffile->sound_offset);
        }

        for (int i = 0; i < num; i++) {
                _cur.nfo_line++;

                /* Check whether the index is in range. This might happen if multiple action 11 are present.
                 * While this is invalid, we do not check for this. But we should prevent it from causing bigger trouble */
                bool invalid = i >= _cur.grffile->num_sounds;

                size_t offs = FioGetPos();

                uint32 len = _cur.grf_container_ver >= 2 ? FioReadDword() : FioReadWord();
                byte type = FioReadByte();

                if (_cur.grf_container_ver >= 2 && type == 0xFD) {
                        /* Reference to sprite section. */
                        if (invalid) {
                                grfmsg(1, "GRFSound: Sound index out of range (multiple Action 11?)");
                                FioSkipBytes(len);
                        } else if (len != 4) {
                                grfmsg(1, "GRFSound: Invalid sprite section import");
                                FioSkipBytes(len);
                        } else {
                                uint32 id = FioReadDword();
                                if (_cur.stage == GLS_INIT) LoadGRFSound(GetGRFSpriteOffset(id), sound + i);
                        }
                        continue;
                }

                if (type != 0xFF) {
                        grfmsg(1, "GRFSound: Unexpected RealSprite found, skipping");
                        FioSkipBytes(7);
                        SkipSpriteData(type, len - 8);
                        continue;
                }

                if (invalid) {
                        grfmsg(1, "GRFSound: Sound index out of range (multiple Action 11?)");
                        FioSkipBytes(len);
                }

                byte action = FioReadByte();
                switch (action) {
                        case 0xFF:
                                /* Allocate sound only in init stage. */
                                if (_cur.stage == GLS_INIT) {
                                        if (_cur.grf_container_ver >= 2) {
                                                grfmsg(1, "GRFSound: Inline sounds are not supported for container version >= 2");
                                        } else {
                                                LoadGRFSound(offs, sound + i);
                                        }
                                }
                                FioSkipBytes(len - 1); // already read <action>
                                break;

                        case 0xFE:
                                if (_cur.stage == GLS_ACTIVATION) {
                                        /* XXX 'Action 0xFE' isn't really specified. It is only mentioned for
                                         * importing sounds, so this is probably all wrong... */
                                        if (FioReadByte() != 0) grfmsg(1, "GRFSound: Import type mismatch");
                                        ImportGRFSound(sound + i);
                                } else {
                                        FioSkipBytes(len - 1); // already read <action>
                                }
                                break;

                        default:
                                grfmsg(1, "GRFSound: Unexpected Action %x found, skipping", action);
                                FioSkipBytes(len - 1); // already read <action>
                                break;
                }
        }
}

/* Action 0x11 (SKIP) */
static void SkipAct11(ByteReader *buf)
{
        /* <11> <num>
         *
         * W num      Number of sound files that follow */

        _cur.skip_sprites = buf->ReadWord();

        grfmsg(3, "SkipAct11: Skipping %d sprites", _cur.skip_sprites);
}

/** Action 0x12 */
static void LoadFontGlyph(ByteReader *buf)
{
        /* <12> <num_def> <font_size> <num_char> <base_char>
         *
         * B num_def      Number of definitions
         * B font_size    Size of font (0 = normal, 1 = small, 2 = large, 3 = mono)
         * B num_char     Number of consecutive glyphs
         * W base_char    First character index */

        uint8 num_def = buf->ReadByte();

        for (uint i = 0; i < num_def; i++) {
                FontSize size    = (FontSize)buf->ReadByte();
                uint8  num_char  = buf->ReadByte();
                uint16 base_char = buf->ReadWord();

                if (size >= FS_END) {
                        grfmsg(1, "LoadFontGlyph: Size %u is not supported, ignoring", size);
                }

                grfmsg(7, "LoadFontGlyph: Loading %u glyph(s) at 0x%04X for size %u", num_char, base_char, size);

                for (uint c = 0; c < num_char; c++) {
                        if (size < FS_END) SetUnicodeGlyph(size, base_char + c, _cur.spriteid);
                        _cur.nfo_line++;
                        LoadNextSprite(_cur.spriteid++, _cur.file_index, _cur.nfo_line, _cur.grf_container_ver);
                }
        }
}

/** Action 0x12 (SKIP) */
static void SkipAct12(ByteReader *buf)
{
        /* <12> <num_def> <font_size> <num_char> <base_char>
         *
         * B num_def      Number of definitions
         * B font_size    Size of font (0 = normal, 1 = small, 2 = large)
         * B num_char     Number of consecutive glyphs
         * W base_char    First character index */

        uint8 num_def = buf->ReadByte();

        for (uint i = 0; i < num_def; i++) {
                /* Ignore 'size' byte */
                buf->ReadByte();

                /* Sum up number of characters */
                _cur.skip_sprites += buf->ReadByte();

                /* Ignore 'base_char' word */
                buf->ReadWord();
        }

        grfmsg(3, "SkipAct12: Skipping %d sprites", _cur.skip_sprites);
}

/** Action 0x13 */
static void TranslateGRFStrings(ByteReader *buf)
{
        /* <13> <grfid> <num-ent> <offset> <text...>
         *
         * 4*B grfid     The GRFID of the file whose texts are to be translated
         * B   num-ent   Number of strings
         * W   offset    First text ID
         * S   text...   Zero-terminated strings */

        uint32 grfid = buf->ReadDWord();
        const GRFConfig *c = GetGRFConfig(grfid);
        if (c == nullptr || (c->status != GCS_INITIALISED && c->status != GCS_ACTIVATED)) {
                grfmsg(7, "TranslateGRFStrings: GRFID 0x%08x unknown, skipping action 13", BSWAP32(grfid));
                return;
        }

        if (c->status == GCS_INITIALISED) {
                /* If the file is not active but will be activated later, give an error
                 * and disable this file. */
                GRFError *error = DisableGrf(STR_NEWGRF_ERROR_LOAD_AFTER);

                char tmp[256];
                GetString(tmp, STR_NEWGRF_ERROR_AFTER_TRANSLATED_FILE, lastof(tmp));
                error->data = stredup(tmp);

                return;
        }

        /* Since no language id is supplied for with version 7 and lower NewGRFs, this string has
         * to be added as a generic string, thus the language id of 0x7F. For this to work
         * new_scheme has to be true as well, which will also be implicitly the case for version 8
         * and higher. A language id of 0x7F will be overridden by a non-generic id, so this will
         * not change anything if a string has been provided specifically for this language. */
        byte language = _cur.grffile->grf_version >= 8 ? buf->ReadByte() : 0x7F;
        byte num_strings = buf->ReadByte();
        uint16 first_id  = buf->ReadWord();

        if (!((first_id >= 0xD000 && first_id + num_strings <= 0xD400) || (first_id >= 0xD800 && first_id + num_strings <= 0xE000))) {
                grfmsg(7, "TranslateGRFStrings: Attempting to set out-of-range string IDs in action 13 (first: 0x%4X, number: 0x%2X)", first_id, num_strings);
                return;
        }

        for (uint i = 0; i < num_strings && buf->HasData(); i++) {
                const char *string = buf->ReadString();

                if (StrEmpty(string)) {
                        grfmsg(7, "TranslateGRFString: Ignoring empty string.");
                        continue;
                }

                AddGRFString(grfid, first_id + i, language, true, true, string, STR_UNDEFINED);
        }
}

/** Callback function for 'INFO'->'NAME' to add a translation to the newgrf name. */
static bool ChangeGRFName(byte langid, const char *str)
{
        AddGRFTextToList(&_cur.grfconfig->name->text, langid, _cur.grfconfig->ident.grfid, false, str);
        return true;
}

/** Callback function for 'INFO'->'DESC' to add a translation to the newgrf description. */
static bool ChangeGRFDescription(byte langid, const char *str)
{
        AddGRFTextToList(&_cur.grfconfig->info->text, langid, _cur.grfconfig->ident.grfid, true, str);
        return true;
}

/** Callback function for 'INFO'->'URL_' to set the newgrf url. */
static bool ChangeGRFURL(byte langid, const char *str)
{
        AddGRFTextToList(&_cur.grfconfig->url->text, langid, _cur.grfconfig->ident.grfid, false, str);
        return true;
}

/** Callback function for 'INFO'->'NPAR' to set the number of valid parameters. */
static bool ChangeGRFNumUsedParams(size_t len, ByteReader *buf)
{
        if (len != 1) {
                grfmsg(2, "StaticGRFInfo: expected only 1 byte for 'INFO'->'NPAR' but got " PRINTF_SIZE ", ignoring this field", len);
                buf->Skip(len);
        } else {
                _cur.grfconfig->num_valid_params = min(buf->ReadByte(), lengthof(_cur.grfconfig->param));
        }
        return true;
}

/** Callback function for 'INFO'->'PALS' to set the number of valid parameters. */
static bool ChangeGRFPalette(size_t len, ByteReader *buf)
{
        if (len != 1) {
                grfmsg(2, "StaticGRFInfo: expected only 1 byte for 'INFO'->'PALS' but got " PRINTF_SIZE ", ignoring this field", len);
                buf->Skip(len);
        } else {
                char data = buf->ReadByte();
                GRFPalette pal = GRFP_GRF_UNSET;
                switch (data) {
                        case '*':
                        case 'A': pal = GRFP_GRF_ANY;     break;
                        case 'W': pal = GRFP_GRF_WINDOWS; break;
                        case 'D': pal = GRFP_GRF_DOS;     break;
                        default:
                                grfmsg(2, "StaticGRFInfo: unexpected value '%02x' for 'INFO'->'PALS', ignoring this field", data);
                                break;
                }
                if (pal != GRFP_GRF_UNSET) {
                        _cur.grfconfig->palette &= ~GRFP_GRF_MASK;
                        _cur.grfconfig->palette |= pal;
                }
        }
        return true;
}

/** Callback function for 'INFO'->'BLTR' to set the blitter info. */
static bool ChangeGRFBlitter(size_t len, ByteReader *buf)
{
        if (len != 1) {
                grfmsg(2, "StaticGRFInfo: expected only 1 byte for 'INFO'->'BLTR' but got " PRINTF_SIZE ", ignoring this field", len);
                buf->Skip(len);
        } else {
                char data = buf->ReadByte();
                GRFPalette pal = GRFP_BLT_UNSET;
                switch (data) {
                        case '8': pal = GRFP_BLT_UNSET; break;
                        case '3': pal = GRFP_BLT_32BPP;  break;
                        default:
                                grfmsg(2, "StaticGRFInfo: unexpected value '%02x' for 'INFO'->'BLTR', ignoring this field", data);
                                return true;
                }
                _cur.grfconfig->palette &= ~GRFP_BLT_MASK;
                _cur.grfconfig->palette |= pal;
        }
        return true;
}

/** Callback function for 'INFO'->'VRSN' to the version of the NewGRF. */
static bool ChangeGRFVersion(size_t len, ByteReader *buf)
{
        if (len != 4) {
                grfmsg(2, "StaticGRFInfo: expected 4 bytes for 'INFO'->'VRSN' but got " PRINTF_SIZE ", ignoring this field", len);
                buf->Skip(len);
        } else {
                /* Set min_loadable_version as well (default to minimal compatibility) */
                _cur.grfconfig->version = _cur.grfconfig->min_loadable_version = buf->ReadDWord();
        }
        return true;
}

/** Callback function for 'INFO'->'MINV' to the minimum compatible version of the NewGRF. */
static bool ChangeGRFMinVersion(size_t len, ByteReader *buf)
{
        if (len != 4) {
                grfmsg(2, "StaticGRFInfo: expected 4 bytes for 'INFO'->'MINV' but got " PRINTF_SIZE ", ignoring this field", len);
                buf->Skip(len);
        } else {
                _cur.grfconfig->min_loadable_version = buf->ReadDWord();
                if (_cur.grfconfig->version == 0) {
                        grfmsg(2, "StaticGRFInfo: 'MINV' defined before 'VRSN' or 'VRSN' set to 0, ignoring this field");
                        _cur.grfconfig->min_loadable_version = 0;
                }
                if (_cur.grfconfig->version < _cur.grfconfig->min_loadable_version) {
                        grfmsg(2, "StaticGRFInfo: 'MINV' defined as %d, limiting it to 'VRSN'", _cur.grfconfig->min_loadable_version);
                        _cur.grfconfig->min_loadable_version = _cur.grfconfig->version;
                }
        }
        return true;
}

static GRFParameterInfo *_cur_parameter; ///< The parameter which info is currently changed by the newgrf.

/** Callback function for 'INFO'->'PARAM'->param_num->'NAME' to set the name of a parameter. */
static bool ChangeGRFParamName(byte langid, const char *str)
{
        AddGRFTextToList(&_cur_parameter->name, langid, _cur.grfconfig->ident.grfid, false, str);
        return true;
}

/** Callback function for 'INFO'->'PARAM'->param_num->'DESC' to set the description of a parameter. */
static bool ChangeGRFParamDescription(byte langid, const char *str)
{
        AddGRFTextToList(&_cur_parameter->desc, langid, _cur.grfconfig->ident.grfid, true, str);
        return true;
}

/** Callback function for 'INFO'->'PARAM'->param_num->'TYPE' to set the typeof a parameter. */
static bool ChangeGRFParamType(size_t len, ByteReader *buf)
{
        if (len != 1) {
                grfmsg(2, "StaticGRFInfo: expected 1 byte for 'INFO'->'PARA'->'TYPE' but got " PRINTF_SIZE ", ignoring this field", len);
                buf->Skip(len);
        } else {
                GRFParameterType type = (GRFParameterType)buf->ReadByte();
                if (type < PTYPE_END) {
                        _cur_parameter->type = type;
                } else {
                        grfmsg(3, "StaticGRFInfo: unknown parameter type %d, ignoring this field", type);
                }
        }
        return true;
}

/** Callback function for 'INFO'->'PARAM'->param_num->'LIMI' to set the min/max value of a parameter. */
static bool ChangeGRFParamLimits(size_t len, ByteReader *buf)
{
        if (_cur_parameter->type != PTYPE_UINT_ENUM) {
                grfmsg(2, "StaticGRFInfo: 'INFO'->'PARA'->'LIMI' is only valid for parameters with type uint/enum, ignoring this field");
                buf->Skip(len);
        } else if (len != 8) {
                grfmsg(2, "StaticGRFInfo: expected 8 bytes for 'INFO'->'PARA'->'LIMI' but got " PRINTF_SIZE ", ignoring this field", len);
                buf->Skip(len);
        } else {
                _cur_parameter->min_value = buf->ReadDWord();
                _cur_parameter->max_value = buf->ReadDWord();
        }
        return true;
}

/** Callback function for 'INFO'->'PARAM'->param_num->'MASK' to set the parameter and bits to use. */
static bool ChangeGRFParamMask(size_t len, ByteReader *buf)
{
        if (len < 1 || len > 3) {
                grfmsg(2, "StaticGRFInfo: expected 1 to 3 bytes for 'INFO'->'PARA'->'MASK' but got " PRINTF_SIZE ", ignoring this field", len);
                buf->Skip(len);
        } else {
                byte param_nr = buf->ReadByte();
                if (param_nr >= lengthof(_cur.grfconfig->param)) {
                        grfmsg(2, "StaticGRFInfo: invalid parameter number in 'INFO'->'PARA'->'MASK', param %d, ignoring this field", param_nr);
                        buf->Skip(len - 1);
                } else {
                        _cur_parameter->param_nr = param_nr;
                        if (len >= 2) _cur_parameter->first_bit = min(buf->ReadByte(), 31);
                        if (len >= 3) _cur_parameter->num_bit = min(buf->ReadByte(), 32 - _cur_parameter->first_bit);
                }
        }

        return true;
}

/** Callback function for 'INFO'->'PARAM'->param_num->'DFLT' to set the default value. */
static bool ChangeGRFParamDefault(size_t len, ByteReader *buf)
{
        if (len != 4) {
                grfmsg(2, "StaticGRFInfo: expected 4 bytes for 'INFO'->'PARA'->'DEFA' but got " PRINTF_SIZE ", ignoring this field", len);
                buf->Skip(len);
        } else {
                _cur_parameter->def_value = buf->ReadDWord();
        }
        _cur.grfconfig->has_param_defaults = true;
        return true;
}

typedef bool (*DataHandler)(size_t, ByteReader *);  ///< Type of callback function for binary nodes
typedef bool (*TextHandler)(byte, const char *str); ///< Type of callback function for text nodes
typedef bool (*BranchHandler)(ByteReader *);        ///< Type of callback function for branch nodes

/**
 * Data structure to store the allowed id/type combinations for action 14. The
 * data can be represented as a tree with 3 types of nodes:
 * 1. Branch nodes (identified by 'C' for choice).
 * 2. Binary leaf nodes (identified by 'B').
 * 3. Text leaf nodes (identified by 'T').
 */
struct AllowedSubtags {
        /** Create empty subtags object used to identify the end of a list. */
        AllowedSubtags() :
                id(0),
                type(0)
        {}

        /**
         * Create a binary leaf node.
         * @param id The id for this node.
         * @param handler The callback function to call.
         */
        AllowedSubtags(uint32 id, DataHandler handler) :
                id(id),
                type('B')
        {
                this->handler.data = handler;
        }

        /**
         * Create a text leaf node.
         * @param id The id for this node.
         * @param handler The callback function to call.
         */
        AllowedSubtags(uint32 id, TextHandler handler) :
                id(id),
                type('T')
        {
                this->handler.text = handler;
        }

        /**
         * Create a branch node with a callback handler
         * @param id The id for this node.
         * @param handler The callback function to call.
         */
        AllowedSubtags(uint32 id, BranchHandler handler) :
                id(id),
                type('C')
        {
                this->handler.call_handler = true;
                this->handler.u.branch = handler;
        }

        /**
         * Create a branch node with a list of sub-nodes.
         * @param id The id for this node.
         * @param subtags Array with all valid subtags.
         */
        AllowedSubtags(uint32 id, AllowedSubtags *subtags) :
                id(id),
                type('C')
        {
                this->handler.call_handler = false;
                this->handler.u.subtags = subtags;
        }

        uint32 id; ///< The identifier for this node
        byte type; ///< The type of the node, must be one of 'C', 'B' or 'T'.
        union {
                DataHandler data; ///< Callback function for a binary node, only valid if type == 'B'.
                TextHandler text; ///< Callback function for a text node, only valid if type == 'T'.
                struct {
                        union {
                                BranchHandler branch;    ///< Callback function for a branch node, only valid if type == 'C' && call_handler.
                                AllowedSubtags *subtags; ///< Pointer to a list of subtags, only valid if type == 'C' && !call_handler.
                        } u;
                        bool call_handler; ///< True if there is a callback function for this node, false if there is a list of subnodes.
                };
        } handler;
};

static bool SkipUnknownInfo(ByteReader *buf, byte type);
static bool HandleNodes(ByteReader *buf, AllowedSubtags *tags);

/**
 * Callback function for 'INFO'->'PARA'->param_num->'VALU' to set the names
 * of some parameter values (type uint/enum) or the names of some bits
 * (type bitmask). In both cases the format is the same:
 * Each subnode should be a text node with the value/bit number as id.
 */
static bool ChangeGRFParamValueNames(ByteReader *buf)
{
        byte type = buf->ReadByte();
        while (type != 0) {
                uint32 id = buf->ReadDWord();
                if (type != 'T' || id > _cur_parameter->max_value) {
                        grfmsg(2, "StaticGRFInfo: all child nodes of 'INFO'->'PARA'->param_num->'VALU' should have type 't' and the value/bit number as id");
                        if (!SkipUnknownInfo(buf, type)) return false;
                        type = buf->ReadByte();
                        continue;
                }

                byte langid = buf->ReadByte();
                const char *name_string = buf->ReadString();

                SmallPair<uint32, GRFText *> *val_name = _cur_parameter->value_names.Find(id);
                if (val_name != _cur_parameter->value_names.End()) {
                        AddGRFTextToList(&val_name->second, langid, _cur.grfconfig->ident.grfid, false, name_string);
                } else {
                        GRFText *list = nullptr;
                        AddGRFTextToList(&list, langid, _cur.grfconfig->ident.grfid, false, name_string);
                        _cur_parameter->value_names.Insert(id, list);
                }

                type = buf->ReadByte();
        }
        return true;
}

/** Action14 parameter tags */
AllowedSubtags _tags_parameters[] = {
        AllowedSubtags('NAME', ChangeGRFParamName),
        AllowedSubtags('DESC', ChangeGRFParamDescription),
        AllowedSubtags('TYPE', ChangeGRFParamType),
        AllowedSubtags('LIMI', ChangeGRFParamLimits),
        AllowedSubtags('MASK', ChangeGRFParamMask),
        AllowedSubtags('VALU', ChangeGRFParamValueNames),
        AllowedSubtags('DFLT', ChangeGRFParamDefault),
        AllowedSubtags()
};

/**
 * Callback function for 'INFO'->'PARA' to set extra information about the
 * parameters. Each subnode of 'INFO'->'PARA' should be a branch node with
 * the parameter number as id. The first parameter has id 0. The maximum
 * parameter that can be changed is set by 'INFO'->'NPAR' which defaults to 80.
 */
static bool HandleParameterInfo(ByteReader *buf)
{
        byte type = buf->ReadByte();
        while (type != 0) {
                uint32 id = buf->ReadDWord();
                if (type != 'C' || id >= _cur.grfconfig->num_valid_params) {
                        grfmsg(2, "StaticGRFInfo: all child nodes of 'INFO'->'PARA' should have type 'C' and their parameter number as id");
                        if (!SkipUnknownInfo(buf, type)) return false;
                        type = buf->ReadByte();
                        continue;
                }

                if (id >= _cur.grfconfig->param_info.Length()) {
                        uint num_to_add = id - _cur.grfconfig->param_info.Length() + 1;
                        GRFParameterInfo **newdata = _cur.grfconfig->param_info.Append(num_to_add);
                        MemSetT<GRFParameterInfo *>(newdata, 0, num_to_add);
                }
                if (_cur.grfconfig->param_info[id] == nullptr) {
                        _cur.grfconfig->param_info[id] = new GRFParameterInfo(id);
                }
                _cur_parameter = _cur.grfconfig->param_info[id];
                /* Read all parameter-data and process each node. */
                if (!HandleNodes(buf, _tags_parameters)) return false;
                type = buf->ReadByte();
        }
        return true;
}

/** Action14 tags for the INFO node */
AllowedSubtags _tags_info[] = {
        AllowedSubtags('NAME', ChangeGRFName),
        AllowedSubtags('DESC', ChangeGRFDescription),
        AllowedSubtags('URL_', ChangeGRFURL),
        AllowedSubtags('NPAR', ChangeGRFNumUsedParams),
        AllowedSubtags('PALS', ChangeGRFPalette),
        AllowedSubtags('BLTR', ChangeGRFBlitter),
        AllowedSubtags('VRSN', ChangeGRFVersion),
        AllowedSubtags('MINV', ChangeGRFMinVersion),
        AllowedSubtags('PARA', HandleParameterInfo),
        AllowedSubtags()
};

/** Action14 root tags */
AllowedSubtags _tags_root[] = {
        AllowedSubtags('INFO', _tags_info),
        AllowedSubtags()
};


/**
 * Try to skip the current node and all subnodes (if it's a branch node).
 * @param buf Buffer.
 * @param type The node type to skip.
 * @return True if we could skip the node, false if an error occurred.
 */
static bool SkipUnknownInfo(ByteReader *buf, byte type)
{
        /* type and id are already read */
        switch (type) {
                case 'C': {
                        byte new_type = buf->ReadByte();
                        while (new_type != 0) {
                                buf->ReadDWord(); // skip the id
                                if (!SkipUnknownInfo(buf, new_type)) return false;
                                new_type = buf->ReadByte();
                        }
                        break;
                }

                case 'T':
                        buf->ReadByte(); // lang
                        buf->ReadString(); // actual text
                        break;

                case 'B': {
                        uint16 size = buf->ReadWord();
                        buf->Skip(size);
                        break;
                }

                default:
                        return false;
        }

        return true;
}

/**
 * Handle the nodes of an Action14
 * @param type Type of node.
 * @param id ID.
 * @param buf Buffer.
 * @param subtags Allowed subtags.
 * @return Whether all tags could be handled.
 */
static bool HandleNode(byte type, uint32 id, ByteReader *buf, AllowedSubtags subtags[])
{
        uint i = 0;
        AllowedSubtags *tag;
        while ((tag = &subtags[i++])->type != 0) {
                if (tag->id != BSWAP32(id) || tag->type != type) continue;
                switch (type) {
                        default: NOT_REACHED();

                        case 'T': {
                                byte langid = buf->ReadByte();
                                return tag->handler.text(langid, buf->ReadString());
                        }

                        case 'B': {
                                size_t len = buf->ReadWord();
                                if (buf->Remaining() < len) return false;
                                return tag->handler.data(len, buf);
                        }

                        case 'C': {
                                if (tag->handler.call_handler) {
                                        return tag->handler.u.branch(buf);
                                }
                                return HandleNodes(buf, tag->handler.u.subtags);
                        }
                }
        }
        grfmsg(2, "StaticGRFInfo: unknown type/id combination found, type=%c, id=%x", type, id);
        return SkipUnknownInfo(buf, type);
}

/**
 * Handle the contents of a 'C' choice of an Action14
 * @param buf Buffer.
 * @param subtags List of subtags.
 * @return Whether the nodes could all be handled.
 */
static bool HandleNodes(ByteReader *buf, AllowedSubtags subtags[])
{
        byte type = buf->ReadByte();
        while (type != 0) {
                uint32 id = buf->ReadDWord();
                if (!HandleNode(type, id, buf, subtags)) return false;
                type = buf->ReadByte();
        }
        return true;
}

/**
 * Handle Action 0x14
 * @param buf Buffer.
 */
static void StaticGRFInfo(ByteReader *buf)
{
        /* <14> <type> <id> <text/data...> */
        HandleNodes(buf, _tags_root);
}

/**
 * Set the current NewGRF as unsafe for static use
 * @param buf Unused.
 * @note Used during safety scan on unsafe actions.
 */
static void GRFUnsafe(ByteReader *buf)
{
        SetBit(_cur.grfconfig->flags, GCF_UNSAFE);

        /* Skip remainder of GRF */
        _cur.skip_sprites = -1;
}


/** Initialize the TTDPatch flags */
static void InitializeGRFSpecial()
{
        _ttdpatch_flags[0] = ((_settings_game.station.never_expire_airports ? 1 : 0) << 0x0C)  // keepsmallairport
                                           |                                                      (1 << 0x0D)  // newairports
                                           |                                                      (1 << 0x0E)  // largestations
                                           | ((_settings_game.construction.max_bridge_length > 16 ? 1 : 0) << 0x0F)  // longbridges
                                           |                                                      (0 << 0x10)  // loadtime
                                           |                                                      (1 << 0x12)  // presignals
                                           |                                                      (1 << 0x13)  // extpresignals
                                           | ((_settings_game.vehicle.never_expire_vehicles ? 1 : 0) << 0x16)  // enginespersist
                                           |                                                      (1 << 0x1B)  // multihead
                                           |                                                      (1 << 0x1D)  // lowmemory
                                           |                                                      (1 << 0x1E); // generalfixes

        _ttdpatch_flags[1] =   ((_settings_game.economy.station_noise_level ? 1 : 0) << 0x07)  // moreairports - based on units of noise
                                           |                                                      (1 << 0x08)  // mammothtrains
                                           |                                                      (1 << 0x09)  // trainrefit
                                           |                                                      (0 << 0x0B)  // subsidiaries
                                           |         ((_settings_game.order.gradual_loading ? 1 : 0) << 0x0C)  // gradualloading
                                           |                                                      (1 << 0x12)  // unifiedmaglevmode - set bit 0 mode. Not revelant to OTTD
                                           |                                                      (1 << 0x13)  // unifiedmaglevmode - set bit 1 mode
                                           |                                                      (1 << 0x14)  // bridgespeedlimits
                                           |                                                      (1 << 0x16)  // eternalgame
                                           |                                                      (1 << 0x17)  // newtrains
                                           |                                                      (1 << 0x18)  // newrvs
                                           |                                                      (1 << 0x19)  // newships
                                           |                                                      (1 << 0x1A)  // newplanes
                                           | ((_settings_game.construction.train_signal_side == 1 ? 1 : 0) << 0x1B)  // signalsontrafficside
                                           |       ((_settings_game.vehicle.disable_elrails ? 0 : 1) << 0x1C); // electrifiedrailway

        _ttdpatch_flags[2] =                                                      (1 << 0x01)  // loadallgraphics - obsolote
                                           |                                                      (1 << 0x03)  // semaphores
                                           |                                                      (1 << 0x0A)  // newobjects
                                           |                                                      (0 << 0x0B)  // enhancedgui
                                           |                                                      (0 << 0x0C)  // newagerating
                                           |  ((_settings_game.construction.build_on_slopes ? 1 : 0) << 0x0D)  // buildonslopes
                                           |                                                      (1 << 0x0E)  // fullloadany
                                           |                                                      (1 << 0x0F)  // planespeed
                                           |                                                      (0 << 0x10)  // moreindustriesperclimate - obsolete
                                           |                                                      (0 << 0x11)  // moretoylandfeatures
                                           |                                                      (1 << 0x12)  // newstations
                                           |                                                      (1 << 0x13)  // tracktypecostdiff
                                           |                                                      (1 << 0x14)  // manualconvert
                                           |  ((_settings_game.construction.build_on_slopes ? 1 : 0) << 0x15)  // buildoncoasts
                                           |                                                      (1 << 0x16)  // canals
                                           |                                                      (1 << 0x17)  // newstartyear
                                           |    ((_settings_game.vehicle.freight_trains > 1 ? 1 : 0) << 0x18)  // freighttrains
                                           |                                                      (1 << 0x19)  // newhouses
                                           |                                                      (1 << 0x1A)  // newbridges
                                           |                                                      (1 << 0x1B)  // newtownnames
                                           |                                                      (1 << 0x1C)  // moreanimation
                                           |    ((_settings_game.vehicle.wagon_speed_limits ? 1 : 0) << 0x1D)  // wagonspeedlimits
                                           |                                                      (1 << 0x1E)  // newshistory
                                           |                                                      (0 << 0x1F); // custombridgeheads

        _ttdpatch_flags[3] =                                                      (0 << 0x00)  // newcargodistribution
                                           |                                                      (1 << 0x01)  // windowsnap
                                           | ((_settings_game.economy.allow_town_roads || _generating_world ? 0 : 1) << 0x02)  // townbuildnoroad
                                           |                                                      (1 << 0x03)  // pathbasedsignalling
                                           |                                                      (0 << 0x04)  // aichoosechance
                                           |                                                      (1 << 0x05)  // resolutionwidth
                                           |                                                      (1 << 0x06)  // resolutionheight
                                           |                                                      (1 << 0x07)  // newindustries
                                           |           ((_settings_game.order.improved_load ? 1 : 0) << 0x08)  // fifoloading
                                           |                                                      (0 << 0x09)  // townroadbranchprob
                                           |                                                      (0 << 0x0A)  // tempsnowline
                                           |                                                      (1 << 0x0B)  // newcargo
                                           |                                                      (1 << 0x0C)  // enhancemultiplayer
                                           |                                                      (1 << 0x0D)  // onewayroads
                                           |                                                      (1 << 0x0E)  // irregularstations
                                           |                                                      (1 << 0x0F)  // statistics
                                           |                                                      (1 << 0x10)  // newsounds
                                           |                                                      (1 << 0x11)  // autoreplace
                                           |                                                      (1 << 0x12)  // autoslope
                                           |                                                      (0 << 0x13)  // followvehicle
                                           |                                                      (1 << 0x14)  // trams
                                           |                                                      (0 << 0x15)  // enhancetunnels
                                           |                                                      (1 << 0x16)  // shortrvs
                                           |                                                      (1 << 0x17)  // articulatedrvs
                                           |       ((_settings_game.vehicle.dynamic_engines ? 1 : 0) << 0x18)  // dynamic engines
                                           |                                                      (1 << 0x1E)  // variablerunningcosts
                                           |                                                      (1 << 0x1F); // any switch is on
}

/** Reset and clear all NewGRF stations */
static void ResetCustomStations()
{
        const GRFFile * const *end = _grf_files.End();
        for (GRFFile **file = _grf_files.Begin(); file != end; file++) {
                StationSpec **&stations = (*file)->stations;
                if (stations == nullptr) continue;
                for (uint i = 0; i < NUM_STATIONS_PER_GRF; i++) {
                        if (stations[i] == nullptr) continue;
                        StationSpec *statspec = stations[i];

                        delete[] statspec->renderdata;

                        /* Release platforms and layouts */
                        if (!statspec->copied_layouts) {
                                for (uint l = 0; l < statspec->lengths; l++) {
                                        for (uint p = 0; p < statspec->platforms[l]; p++) {
                                                free(statspec->layouts[l][p]);
                                        }
                                        free(statspec->layouts[l]);
                                }
                                free(statspec->layouts);
                                free(statspec->platforms);
                        }

                        /* Release this station */
                        free(statspec);
                }

                /* Free and reset the station data */
                free(stations);
                stations = nullptr;
        }
}

/** Reset and clear all NewGRF houses */
static void ResetCustomHouses()
{
        const GRFFile * const *end = _grf_files.End();
        for (GRFFile **file = _grf_files.Begin(); file != end; file++) {
                HouseSpec **&housespec = (*file)->housespec;
                if (housespec == nullptr) continue;
                for (uint i = 0; i < NUM_HOUSES_PER_GRF; i++) {
                        free(housespec[i]);
                }

                free(housespec);
                housespec = nullptr;
        }
}

/** Reset and clear all NewGRF airports */
static void ResetCustomAirports()
{
        const GRFFile * const *end = _grf_files.End();
        for (GRFFile **file = _grf_files.Begin(); file != end; file++) {
                AirportSpec **aslist = (*file)->airportspec;
                if (aslist != nullptr) {
                        for (uint i = 0; i < NUM_AIRPORTS_PER_GRF; i++) {
                                AirportSpec *as = aslist[i];

                                if (as != nullptr) {
                                        /* We need to remove the tiles layouts */
                                        for (int j = 0; j < as->num_table; j++) {
                                                /* remove the individual layouts */
                                                free(as->table[j]);
                                        }
                                        free(as->table);
                                        free(as->depot_table);
                                        free(as->rotation);

                                        free(as);
                                }
                        }
                        free(aslist);
                        (*file)->airportspec = nullptr;
                }

                AirportTileSpec **&airporttilespec = (*file)->airtspec;
                if (airporttilespec != nullptr) {
                        for (uint i = 0; i < NUM_AIRPORTTILES_PER_GRF; i++) {
                                free(airporttilespec[i]);
                        }
                        free(airporttilespec);
                        airporttilespec = nullptr;
                }
        }
}

/** Reset and clear all NewGRF industries */
static void ResetCustomIndustries()
{
        const GRFFile * const *end = _grf_files.End();
        for (GRFFile **file = _grf_files.Begin(); file != end; file++) {
                IndustrySpec **&industryspec = (*file)->industryspec;
                IndustryTileSpec **&indtspec = (*file)->indtspec;

                /* We are verifiying both tiles and industries specs loaded from the grf file
                 * First, let's deal with industryspec */
                if (industryspec != nullptr) {
                        for (uint i = 0; i < NUM_INDUSTRYTYPES_PER_GRF; i++) {
                                IndustrySpec *ind = industryspec[i];
                                if (ind == nullptr) continue;

                                /* We need to remove the sounds array */
                                if (HasBit(ind->cleanup_flag, CLEAN_RANDOMSOUNDS)) {
                                        free(ind->random_sounds);
                                }

                                /* We need to remove the tiles layouts */
                                CleanIndustryTileTable(ind);

                                free(ind);
                        }

                        free(industryspec);
                        industryspec = nullptr;
                }

                if (indtspec == nullptr) continue;
                for (uint i = 0; i < NUM_INDUSTRYTILES_PER_GRF; i++) {
                        free(indtspec[i]);
                }

                free(indtspec);
                indtspec = nullptr;
        }
}

/** Reset and clear all NewObjects */
static void ResetCustomObjects()
{
        const GRFFile * const *end = _grf_files.End();
        for (GRFFile **file = _grf_files.Begin(); file != end; file++) {
                ObjectSpec **&objectspec = (*file)->objectspec;
                if (objectspec == nullptr) continue;
                for (uint i = 0; i < NUM_OBJECTS_PER_GRF; i++) {
                        free(objectspec[i]);
                }

                free(objectspec);
                objectspec = nullptr;
        }
}

/** Reset and clear all NewGRFs */
static void ResetNewGRF()
{
        const GRFFile * const *end = _grf_files.End();
        for (GRFFile **file = _grf_files.Begin(); file != end; file++) {
                delete *file;
        }

        _grf_files.Clear();
        _cur.grffile   = nullptr;
}

/** Clear all NewGRF errors */
static void ResetNewGRFErrors()
{
        for (GRFConfig *c = _grfconfig; c != nullptr; c = c->next) {
                if (!HasBit(c->flags, GCF_COPY) && c->error != nullptr) {
                        delete c->error;
                        c->error = nullptr;
                }
        }
}

/**
 * Reset all NewGRF loaded data
 */
void ResetNewGRFData()
{
        CleanUpStrings();
        CleanUpGRFTownNames();

        /* Copy/reset original engine info data */
        SetupEngines();

        /* Copy/reset original bridge info data */
        ResetBridges();

        /* Reset rail type information */
        ResetRailTypes();

        /* Copy/reset original road type info data */
        ResetRoadTypes();

        /* Allocate temporary refit/cargo class data */
        _gted = CallocT<GRFTempEngineData>(Engine::GetPoolSize());

        /* Fill rail type label temporary data for default trains */
        Engine *e;
        FOR_ALL_ENGINES_OF_TYPE(e, VEH_TRAIN) {
                _gted[e->index].railtypelabel = GetRailTypeInfo(e->u.rail.railtype)->label;
        }

        /* Reset GRM reservations */
        memset(&_grm_engines, 0, sizeof(_grm_engines));
        memset(&_grm_cargoes, 0, sizeof(_grm_cargoes));

        /* Reset generic feature callback lists */
        ResetGenericCallbacks();

        /* Reset price base data */
        ResetPriceBaseMultipliers();

        /* Reset the curencies array */
        ResetCurrencies();

        /* Reset the house array */
        ResetCustomHouses();
        ResetHouses();

        /* Reset the industries structures*/
        ResetCustomIndustries();
        ResetIndustries();

        /* Reset the objects. */
        ObjectClass::Reset();
        ResetCustomObjects();
        ResetObjects();

        /* Reset station classes */
        StationClass::Reset();
        ResetCustomStations();

        /* Reset airport-related structures */
        AirportClass::Reset();
        ResetCustomAirports();
        AirportSpec::ResetAirports();
        AirportTileSpec::ResetAirportTiles();

        /* Reset canal sprite groups and flags */
        memset(_water_feature, 0, sizeof(_water_feature));

        /* Reset the snowline table. */
        ClearSnowLine();

        /* Reset NewGRF files */
        ResetNewGRF();

        /* Reset NewGRF errors. */
        ResetNewGRFErrors();

        /* Set up the default cargo types */
        SetupCargoForClimate(_settings_game.game_creation.landscape);

        /* Reset misc GRF features and train list display variables */
        _misc_grf_features = 0;

        _loaded_newgrf_features.has_2CC           = false;
        _loaded_newgrf_features.used_liveries     = 1 << LS_DEFAULT;
        _loaded_newgrf_features.has_newhouses     = false;
        _loaded_newgrf_features.has_newindustries = false;
        _loaded_newgrf_features.shore             = SHORE_REPLACE_NONE;
        _loaded_newgrf_features.tram              = TRAMWAY_REPLACE_DEPOT_NONE;

        /* Clear all GRF overrides */
        _grf_id_overrides.clear();

        InitializeSoundPool();
        _spritegroup_pool.CleanPool();
}

/**
 * Reset NewGRF data which is stored persistently in savegames.
 */
void ResetPersistentNewGRFData()
{
        /* Reset override managers */
        _engine_mngr.ResetToDefaultMapping();
        _house_mngr.ResetMapping();
        _industry_mngr.ResetMapping();
        _industile_mngr.ResetMapping();
        _airport_mngr.ResetMapping();
        _airporttile_mngr.ResetMapping();
}

/**
 * Construct the Cargo Mapping
 * @note This is the reverse of a cargo translation table
 */
static void BuildCargoTranslationMap()
{
        memset(_cur.grffile->cargo_map, 0xFF, sizeof(_cur.grffile->cargo_map));

        for (CargoID c = 0; c < NUM_CARGO; c++) {
                const CargoSpec *cs = CargoSpec::Get(c);
                if (!cs->IsValid()) continue;

                if (_cur.grffile->cargo_list.Length() == 0) {
                        /* Default translation table, so just a straight mapping to bitnum */
                        _cur.grffile->cargo_map[c] = cs->bitnum;
                } else {
                        /* Check the translation table for this cargo's label */
                        int index = _cur.grffile->cargo_list.FindIndex(cs->label);
                        if (index >= 0) _cur.grffile->cargo_map[c] = index;
                }
        }
}

/**
 * Prepare loading a NewGRF file with its config
 * @param config The NewGRF configuration struct with name, id, parameters and alike.
 */
static void InitNewGRFFile(const GRFConfig *config)
{
        GRFFile *newfile = GetFileByFilename(config->filename);
        if (newfile != nullptr) {
                /* We already loaded it once. */
                _cur.grffile = newfile;
                return;
        }

        newfile = new GRFFile(config);
        *_grf_files.Append() = _cur.grffile = newfile;
}

/**
 * Constructor for GRFFile
 * @param config GRFConfig to copy name, grfid and parameters from.
 */
GRFFile::GRFFile(const GRFConfig *config)
{
        this->filename = stredup(config->filename);
        this->grfid = config->ident.grfid;

        /* Initialise local settings to defaults */
        this->traininfo_vehicle_pitch = 0;
        this->traininfo_vehicle_width = TRAININFO_DEFAULT_VEHICLE_WIDTH;

        /* Mark price_base_multipliers as 'not set' */
        for (Price i = PR_BEGIN; i < PR_END; i++) {
                this->price_base_multipliers[i] = INVALID_PRICE_MODIFIER;
        }

        /* Initialise rail type map with default rail types */
        memset(this->railtype_map, INVALID_RAILTYPE, sizeof(this->railtype_map));
        this->railtype_map[0] = RAILTYPE_RAIL;
        this->railtype_map[1] = RAILTYPE_ELECTRIC;
        this->railtype_map[2] = RAILTYPE_MONO;
        this->railtype_map[3] = RAILTYPE_MAGLEV;

        /* Initialise road type map with default road types */
        memset(this->roadtype_map, INVALID_ROADSUBTYPE, sizeof(this->roadtype_map));
        this->roadtype_map[ROADTYPE_ROAD][0] = ROADSUBTYPE_NORMAL;
        this->roadtype_map[ROADTYPE_ROAD][1] = ROADSUBTYPE_ELECTRIC;
        this->roadtype_map[ROADTYPE_TRAM][0] = ROADSUBTYPE_NORMAL;
        this->roadtype_map[ROADTYPE_TRAM][1] = ROADSUBTYPE_ELECTRIC;

        /* Copy the initial parameter list
         * 'Uninitialised' parameters are zeroed as that is their default value when dynamically creating them. */
        assert_compile(lengthof(this->param) == lengthof(config->param) && lengthof(this->param) == 0x80);

        assert(config->num_params <= lengthof(config->param));
        this->param_end = config->num_params;
        if (this->param_end > 0) {
                MemCpyT(this->param, config->param, this->param_end);
        }
}

GRFFile::~GRFFile()
{
        free(this->filename);
        delete[] this->language_map;
}


/**
 * List of what cargo labels are refittable for the given the vehicle-type.
 * Only currently active labels are applied.
 */
static const CargoLabel _default_refitmasks_rail[] = {
        'PASS', 'COAL', 'MAIL', 'LVST', 'GOOD', 'GRAI', 'WHEA', 'MAIZ', 'WOOD',
        'IORE', 'STEL', 'VALU', 'GOLD', 'DIAM', 'PAPR', 'FOOD', 'FRUT', 'CORE',
        'WATR', 'SUGR', 'TOYS', 'BATT', 'SWET', 'TOFF', 'COLA', 'CTCD', 'BUBL',
        'PLST', 'FZDR',
        0 };

static const CargoLabel _default_refitmasks_road[] = {
        0 };

static const CargoLabel _default_refitmasks_ships[] = {
        'COAL', 'MAIL', 'LVST', 'GOOD', 'GRAI', 'WHEA', 'MAIZ', 'WOOD', 'IORE',
        'STEL', 'VALU', 'GOLD', 'DIAM', 'PAPR', 'FOOD', 'FRUT', 'CORE', 'WATR',
        'RUBR', 'SUGR', 'TOYS', 'BATT', 'SWET', 'TOFF', 'COLA', 'CTCD', 'BUBL',
        'PLST', 'FZDR',
        0 };

static const CargoLabel _default_refitmasks_aircraft[] = {
        'PASS', 'MAIL', 'GOOD', 'VALU', 'GOLD', 'DIAM', 'FOOD', 'FRUT', 'SUGR',
        'TOYS', 'BATT', 'SWET', 'TOFF', 'COLA', 'CTCD', 'BUBL', 'PLST', 'FZDR',
        0 };

static const CargoLabel * const _default_refitmasks[] = {
        _default_refitmasks_rail,
        _default_refitmasks_road,
        _default_refitmasks_ships,
        _default_refitmasks_aircraft,
};


/**
 * Precalculate refit masks from cargo classes for all vehicles.
 */
static void CalculateRefitMasks()
{
        Engine *e;

        FOR_ALL_ENGINES(e) {
                EngineID engine = e->index;
                EngineInfo *ei = &e->info;
                bool only_defaultcargo; ///< Set if the vehicle shall carry only the default cargo

                /* Did the newgrf specify any refitting? If not, use defaults. */
                if (_gted[engine].refittability != GRFTempEngineData::UNSET) {
                        uint32 mask = 0;
                        uint32 not_mask = 0;
                        uint32 xor_mask = ei->refit_mask;

                        /* If the original masks set by the grf are zero, the vehicle shall only carry the default cargo.
                         * Note: After applying the translations, the vehicle may end up carrying no defined cargo. It becomes unavailable in that case. */
                        only_defaultcargo = _gted[engine].refittability == GRFTempEngineData::EMPTY;

                        if (_gted[engine].cargo_allowed != 0) {
                                /* Build up the list of cargo types from the set cargo classes. */
                                const CargoSpec *cs;
                                FOR_ALL_CARGOSPECS(cs) {
                                        if (_gted[engine].cargo_allowed    & cs->classes) SetBit(mask,     cs->Index());
                                        if (_gted[engine].cargo_disallowed & cs->classes) SetBit(not_mask, cs->Index());
                                }
                        }

                        ei->refit_mask = ((mask & ~not_mask) ^ xor_mask) & _cargo_mask;

                        /* Apply explicit refit includes/excludes. */
                        ei->refit_mask |= _gted[engine].ctt_include_mask;
                        ei->refit_mask &= ~_gted[engine].ctt_exclude_mask;
                } else {
                        uint32 xor_mask = 0;

                        /* Don't apply default refit mask to wagons nor engines with no capacity */
                        if (e->type != VEH_TRAIN || (e->u.rail.capacity != 0 && e->u.rail.railveh_type != RAILVEH_WAGON)) {
                                const CargoLabel *cl = _default_refitmasks[e->type];
                                for (uint i = 0;; i++) {
                                        if (cl[i] == 0) break;

                                        CargoID cargo = GetCargoIDByLabel(cl[i]);
                                        if (cargo == CT_INVALID) continue;

                                        SetBit(xor_mask, cargo);
                                }
                        }

                        ei->refit_mask = xor_mask & _cargo_mask;

                        /* If the mask is zero, the vehicle shall only carry the default cargo */
                        only_defaultcargo = (ei->refit_mask == 0);
                }

                /* Clear invalid cargoslots (from default vehicles or pre-NewCargo GRFs) */
                if (ei->cargo_type != CT_INVALID && !HasBit(_cargo_mask, ei->cargo_type)) ei->cargo_type = CT_INVALID;

                /* Ensure that the vehicle is either not refittable, or that the default cargo is one of the refittable cargoes.
                 * Note: Vehicles refittable to no cargo are handle differently to vehicle refittable to a single cargo. The latter might have subtypes. */
                if (!only_defaultcargo && (e->type != VEH_SHIP || e->u.ship.old_refittable) && ei->cargo_type != CT_INVALID && !HasBit(ei->refit_mask, ei->cargo_type)) {
                        ei->cargo_type = CT_INVALID;
                }

                /* Check if this engine's cargo type is valid. If not, set to the first refittable
                 * cargo type. Finally disable the vehicle, if there is still no cargo. */
                if (ei->cargo_type == CT_INVALID && ei->refit_mask != 0) {
                        /* Figure out which CTT to use for the default cargo, if it is 'first refittable'. */
                        const uint8 *cargo_map_for_first_refittable = nullptr;
                        {
                                const GRFFile *file = _gted[engine].defaultcargo_grf;
                                if (file == nullptr) file = e->GetGRF();
                                if (file != nullptr && file->grf_version >= 8 && file->cargo_list.Length() != 0) {
                                        cargo_map_for_first_refittable = file->cargo_map;
                                }
                        }

                        if (cargo_map_for_first_refittable != nullptr) {
                                /* Use first refittable cargo from cargo translation table */
                                byte best_local_slot = 0xFF;
                                CargoID cargo_type;
                                FOR_EACH_SET_CARGO_ID(cargo_type, ei->refit_mask) {
                                        byte local_slot = cargo_map_for_first_refittable[cargo_type];
                                        if (local_slot < best_local_slot) {
                                                best_local_slot = local_slot;
                                                ei->cargo_type = cargo_type;
                                        }
                                }
                        }

                        if (ei->cargo_type == CT_INVALID) {
                                /* Use first refittable cargo slot */
                                ei->cargo_type = (CargoID)FindFirstBit(ei->refit_mask);
                        }
                }
                if (ei->cargo_type == CT_INVALID) ei->climates = 0;

                /* Clear refit_mask for not refittable ships */
                if (e->type == VEH_SHIP && !e->u.ship.old_refittable) {
                        ei->refit_mask = 0;
                }
        }
}

/** Set to use the correct action0 properties for each canal feature */
static void FinaliseCanals()
{
        for (uint i = 0; i < CF_END; i++) {
                if (_water_feature[i].grffile != nullptr) {
                        _water_feature[i].callback_mask = _water_feature[i].grffile->canal_local_properties[i].callback_mask;
                        _water_feature[i].flags = _water_feature[i].grffile->canal_local_properties[i].flags;
                }
        }
}

/** Check for invalid engines */
static void FinaliseEngineArray()
{
        Engine *e;

        FOR_ALL_ENGINES(e) {
                if (e->GetGRF() == nullptr) {
                        const EngineIDMapping &eid = _engine_mngr[e->index];
                        if (eid.grfid != INVALID_GRFID || eid.internal_id != eid.substitute_id) {
                                e->info.string_id = STR_NEWGRF_INVALID_ENGINE;
                        }
                }

                /* When the train does not set property 27 (misc flags), but it
                 * is overridden by a NewGRF graphically we want to disable the
                 * flipping possibility. */
                if (e->type == VEH_TRAIN && !_gted[e->index].prop27_set && e->GetGRF() != nullptr && is_custom_sprite(e->u.rail.image_index)) {
                        ClrBit(e->info.misc_flags, EF_RAIL_FLIPS);
                }

                /* Skip wagons, there livery is defined via the engine */
                if (e->type != VEH_TRAIN || e->u.rail.railveh_type != RAILVEH_WAGON) {
                        LiveryScheme ls = GetEngineLiveryScheme(e->index, INVALID_ENGINE, nullptr);
                        SetBit(_loaded_newgrf_features.used_liveries, ls);
                        /* Note: For ships and roadvehicles we assume that they cannot be refitted between passenger and freight */

                        if (e->type == VEH_TRAIN) {
                                SetBit(_loaded_newgrf_features.used_liveries, LS_FREIGHT_WAGON);
                                switch (ls) {
                                        case LS_STEAM:
                                        case LS_DIESEL:
                                        case LS_ELECTRIC:
                                        case LS_MONORAIL:
                                        case LS_MAGLEV:
                                                SetBit(_loaded_newgrf_features.used_liveries, LS_PASSENGER_WAGON_STEAM + ls - LS_STEAM);
                                                break;

                                        case LS_DMU:
                                        case LS_EMU:
                                                SetBit(_loaded_newgrf_features.used_liveries, LS_PASSENGER_WAGON_DIESEL + ls - LS_DMU);
                                                break;

                                        default: NOT_REACHED();
                                }
                        }
                }
        }
}

/** Check for invalid cargoes */
static void FinaliseCargoArray()
{
        for (CargoID c = 0; c < NUM_CARGO; c++) {
                CargoSpec *cs = CargoSpec::Get(c);
                if (!cs->IsValid()) {
                        cs->name = cs->name_single = cs->units_volume = STR_NEWGRF_INVALID_CARGO;
                        cs->quantifier = STR_NEWGRF_INVALID_CARGO_QUANTITY;
                        cs->abbrev = STR_NEWGRF_INVALID_CARGO_ABBREV;
                }
        }
}

/**
 * Check if a given housespec is valid and disable it if it's not.
 * The housespecs that follow it are used to check the validity of
 * multitile houses.
 * @param hs The housespec to check.
 * @param next1 The housespec that follows \c hs.
 * @param next2 The housespec that follows \c next1.
 * @param next3 The housespec that follows \c next2.
 * @param filename The filename of the newgrf this house was defined in.
 * @return Whether the given housespec is valid.
 */
static bool IsHouseSpecValid(HouseSpec *hs, const HouseSpec *next1, const HouseSpec *next2, const HouseSpec *next3, const char *filename)
{
        if (((hs->building_flags & BUILDING_HAS_2_TILES) != 0 &&
                                (next1 == nullptr || !next1->enabled || (next1->building_flags & BUILDING_HAS_1_TILE) != 0)) ||
                        ((hs->building_flags & BUILDING_HAS_4_TILES) != 0 &&
                                (next2 == nullptr || !next2->enabled || (next2->building_flags & BUILDING_HAS_1_TILE) != 0 ||
                                next3 == nullptr || !next3->enabled || (next3->building_flags & BUILDING_HAS_1_TILE) != 0))) {
                hs->enabled = false;
                if (filename != nullptr) DEBUG(grf, 1, "FinaliseHouseArray: %s defines house %d as multitile, but no suitable tiles follow. Disabling house.", filename, hs->grf_prop.local_id);
                return false;
        }

        /* Some places sum population by only counting north tiles. Other places use all tiles causing desyncs.
         * As the newgrf specs define population to be zero for non-north tiles, we just disable the offending house.
         * If you want to allow non-zero populations somewhen, make sure to sum the population of all tiles in all places. */
        if (((hs->building_flags & BUILDING_HAS_2_TILES) != 0 && next1->population != 0) ||
                        ((hs->building_flags & BUILDING_HAS_4_TILES) != 0 && (next2->population != 0 || next3->population != 0))) {
                hs->enabled = false;
                if (filename != nullptr) DEBUG(grf, 1, "FinaliseHouseArray: %s defines multitile house %d with non-zero population on additional tiles. Disabling house.", filename, hs->grf_prop.local_id);
                return false;
        }

        /* Substitute type is also used for override, and having an override with a different size causes crashes.
         * This check should only be done for NewGRF houses because grf_prop.subst_id is not set for original houses.*/
        if (filename != nullptr && (hs->building_flags & BUILDING_HAS_1_TILE) != (HouseSpec::Get(hs->grf_prop.subst_id)->building_flags & BUILDING_HAS_1_TILE)) {
                hs->enabled = false;
                DEBUG(grf, 1, "FinaliseHouseArray: %s defines house %d with different house size then it's substitute type. Disabling house.", filename, hs->grf_prop.local_id);
                return false;
        }

        /* Make sure that additional parts of multitile houses are not available. */
        if ((hs->building_flags & BUILDING_HAS_1_TILE) == 0 && (hs->building_availability & HZ_ZONALL) != 0 && (hs->building_availability & HZ_CLIMALL) != 0) {
                hs->enabled = false;
                if (filename != nullptr) DEBUG(grf, 1, "FinaliseHouseArray: %s defines house %d without a size but marked it as available. Disabling house.", filename, hs->grf_prop.local_id);
                return false;
        }

        return true;
}

/**
 * Make sure there is at least one house available in the year 0 for the given
 * climate / housezone combination.
 * @param bitmask The climate and housezone to check for. Exactly one climate
 *   bit and one housezone bit should be set.
 */
static void EnsureEarlyHouse(HouseZones bitmask)
{
        std::map<int32, Year> min_year;

        for (int i = 0; i < NUM_HOUSES; i++) {
                HouseSpec *hs = HouseSpec::Get(i);
                if (hs == nullptr || !hs->enabled) continue;
                if ((hs->building_availability & bitmask) != bitmask) continue;
                
                int32 grfid = (hs->grf_prop.grffile != nullptr) ? hs->grf_prop.grffile->grfid : -1;
                min_year[grfid] = MAX_YEAR;
        }

        for (int i = 0; i < NUM_HOUSES; i++) {
                HouseSpec *hs = HouseSpec::Get(i);
                if (hs == nullptr || !hs->enabled) continue;
                if ((hs->building_availability & bitmask) != bitmask) continue;

                int32 grfid = (hs->grf_prop.grffile != nullptr) ? hs->grf_prop.grffile->grfid : -1;
                if (hs->min_year < min_year[grfid]) min_year[grfid] = hs->min_year;
        }

        for (int i = 0; i < NUM_HOUSES; i++) {
                HouseSpec *hs = HouseSpec::Get(i);
                if (hs == nullptr || !hs->enabled) continue;
                if ((hs->building_availability & bitmask) != bitmask) continue;

                int32 grfid = (hs->grf_prop.grffile != nullptr) ? hs->grf_prop.grffile->grfid : -1;
                if (hs->min_year == min_year[grfid]) hs->min_year = 0;
        }
}

/**
 * Add all new houses to the house array. House properties can be set at any
 * time in the GRF file, so we can only add a house spec to the house array
 * after the file has finished loading. We also need to check the dates, due to
 * the TTDPatch behaviour described below that we need to emulate.
 */
static void FinaliseHouseArray()
{
        /* If there are no houses with start dates before 1930, then all houses
         * with start dates of 1930 have them reset to 0. This is in order to be
         * compatible with TTDPatch, where if no houses have start dates before
         * 1930 and the date is before 1930, the game pretends that this is 1930.
         * If there have been any houses defined with start dates before 1930 then
         * the dates are left alone.
         * On the other hand, why 1930? Just 'fix' the houses with the lowest
         * minimum introduction date to 0.
         */
        const GRFFile * const *end = _grf_files.End();
        for (GRFFile **file = _grf_files.Begin(); file != end; file++) {
                HouseSpec **&housespec = (*file)->housespec;
                if (housespec == nullptr) continue;

                for (int i = 0; i < NUM_HOUSES_PER_GRF; i++) {
                        HouseSpec *hs = housespec[i];

                        if (hs == nullptr) continue;

                        const HouseSpec *next1 = (i + 1 < NUM_HOUSES_PER_GRF ? housespec[i + 1] : nullptr);
                        const HouseSpec *next2 = (i + 2 < NUM_HOUSES_PER_GRF ? housespec[i + 2] : nullptr);
                        const HouseSpec *next3 = (i + 3 < NUM_HOUSES_PER_GRF ? housespec[i + 3] : nullptr);

                        if (!IsHouseSpecValid(hs, next1, next2, next3, (*file)->filename)) continue;

                        _house_mngr.SetEntitySpec(hs);
                }
        }

        for (int i = 0; i < NUM_HOUSES; i++) {
                HouseSpec *hs = HouseSpec::Get(i);
                const HouseSpec *next1 = (i + 1 < NUM_HOUSES ? HouseSpec::Get(i + 1) : nullptr);
                const HouseSpec *next2 = (i + 2 < NUM_HOUSES ? HouseSpec::Get(i + 2) : nullptr);
                const HouseSpec *next3 = (i + 3 < NUM_HOUSES ? HouseSpec::Get(i + 3) : nullptr);

                /* We need to check all houses again to we are sure that multitile houses
                 * did get consecutive IDs and none of the parts are missing. */
                if (!IsHouseSpecValid(hs, next1, next2, next3, nullptr)) {
                        /* GetHouseNorthPart checks 3 houses that are directly before
                         * it in the house pool. If any of those houses have multi-tile
                         * flags set it assumes it's part of a multitile house. Since
                         * we can have invalid houses in the pool marked as disabled, we
                         * don't want to have them influencing valid tiles. As such set
                         * building_flags to zero here to make sure any house following
                         * this one in the pool is properly handled as 1x1 house. */
                        hs->building_flags = TILE_NO_FLAG;
                }
        }

        HouseZones climate_mask = (HouseZones)(1 << (_settings_game.game_creation.landscape + 12));
        EnsureEarlyHouse(HZ_ZON1 | climate_mask);
        EnsureEarlyHouse(HZ_ZON2 | climate_mask);
        EnsureEarlyHouse(HZ_ZON3 | climate_mask);
        EnsureEarlyHouse(HZ_ZON4 | climate_mask);
        EnsureEarlyHouse(HZ_ZON5 | climate_mask);

        if (_settings_game.game_creation.landscape == LT_ARCTIC) {
                EnsureEarlyHouse(HZ_ZON1 | HZ_SUBARTC_ABOVE);
                EnsureEarlyHouse(HZ_ZON2 | HZ_SUBARTC_ABOVE);
                EnsureEarlyHouse(HZ_ZON3 | HZ_SUBARTC_ABOVE);
                EnsureEarlyHouse(HZ_ZON4 | HZ_SUBARTC_ABOVE);
                EnsureEarlyHouse(HZ_ZON5 | HZ_SUBARTC_ABOVE);
        }
}

/**
 * Add all new industries to the industry array. Industry properties can be set at any
 * time in the GRF file, so we can only add a industry spec to the industry array
 * after the file has finished loading.
 */
static void FinaliseIndustriesArray()
{
        const GRFFile * const *end = _grf_files.End();
        for (GRFFile **file = _grf_files.Begin(); file != end; file++) {
                IndustrySpec **&industryspec = (*file)->industryspec;
                IndustryTileSpec **&indtspec = (*file)->indtspec;
                if (industryspec != nullptr) {
                        for (int i = 0; i < NUM_INDUSTRYTYPES_PER_GRF; i++) {
                                IndustrySpec *indsp = industryspec[i];

                                if (indsp != nullptr && indsp->enabled) {
                                        StringID strid;
                                        /* process the conversion of text at the end, so to be sure everything will be fine
                                         * and available.  Check if it does not return undefind marker, which is a very good sign of a
                                         * substitute industry who has not changed the string been examined, thus using it as such */
                                        strid = GetGRFStringID(indsp->grf_prop.grffile->grfid, indsp->name);
                                        if (strid != STR_UNDEFINED) indsp->name = strid;

                                        strid = GetGRFStringID(indsp->grf_prop.grffile->grfid, indsp->closure_text);
                                        if (strid != STR_UNDEFINED) indsp->closure_text = strid;

                                        strid = GetGRFStringID(indsp->grf_prop.grffile->grfid, indsp->production_up_text);
                                        if (strid != STR_UNDEFINED) indsp->production_up_text = strid;

                                        strid = GetGRFStringID(indsp->grf_prop.grffile->grfid, indsp->production_down_text);
                                        if (strid != STR_UNDEFINED) indsp->production_down_text = strid;

                                        strid = GetGRFStringID(indsp->grf_prop.grffile->grfid, indsp->new_industry_text);
                                        if (strid != STR_UNDEFINED) indsp->new_industry_text = strid;

                                        if (indsp->station_name != STR_NULL) {
                                                /* STR_NULL (0) can be set by grf.  It has a meaning regarding assignation of the
                                                 * station's name. Don't want to lose the value, therefore, do not process. */
                                                strid = GetGRFStringID(indsp->grf_prop.grffile->grfid, indsp->station_name);
                                                if (strid != STR_UNDEFINED) indsp->station_name = strid;
                                        }

                                        _industry_mngr.SetEntitySpec(indsp);
                                        _loaded_newgrf_features.has_newindustries = true;
                                }
                        }
                }

                if (indtspec != nullptr) {
                        for (int i = 0; i < NUM_INDUSTRYTILES_PER_GRF; i++) {
                                IndustryTileSpec *indtsp = indtspec[i];
                                if (indtsp != nullptr) {
                                        _industile_mngr.SetEntitySpec(indtsp);
                                }
                        }
                }
        }

        for (uint j = 0; j < NUM_INDUSTRYTYPES; j++) {
                IndustrySpec *indsp = &_industry_specs[j];
                if (indsp->enabled && indsp->grf_prop.grffile != nullptr) {
                        for (uint i = 0; i < 3; i++) {
                                indsp->conflicting[i] = MapNewGRFIndustryType(indsp->conflicting[i], indsp->grf_prop.grffile->grfid);
                        }
                }
                if (!indsp->enabled) {
                        indsp->name = STR_NEWGRF_INVALID_INDUSTRYTYPE;
                }
        }
}

/**
 * Add all new objects to the object array. Object properties can be set at any
 * time in the GRF file, so we can only add an object spec to the object array
 * after the file has finished loading.
 */
static void FinaliseObjectsArray()
{
        const GRFFile * const *end = _grf_files.End();
        for (GRFFile **file = _grf_files.Begin(); file != end; file++) {
                ObjectSpec **&objectspec = (*file)->objectspec;
                if (objectspec != nullptr) {
                        for (int i = 0; i < NUM_OBJECTS_PER_GRF; i++) {
                                if (objectspec[i] != nullptr && objectspec[i]->grf_prop.grffile != nullptr && objectspec[i]->enabled) {
                                        _object_mngr.SetEntitySpec(objectspec[i]);
                                }
                        }
                }
        }
}

/**
 * Add all new airports to the airport array. Airport properties can be set at any
 * time in the GRF file, so we can only add a airport spec to the airport array
 * after the file has finished loading.
 */
static void FinaliseAirportsArray()
{
        const GRFFile * const *end = _grf_files.End();
        for (GRFFile **file = _grf_files.Begin(); file != end; file++) {
                AirportSpec **&airportspec = (*file)->airportspec;
                if (airportspec != nullptr) {
                        for (int i = 0; i < NUM_AIRPORTS_PER_GRF; i++) {
                                if (airportspec[i] != nullptr && airportspec[i]->enabled) {
                                        _airport_mngr.SetEntitySpec(airportspec[i]);
                                }
                        }
                }

                AirportTileSpec **&airporttilespec = (*file)->airtspec;
                if (airporttilespec != nullptr) {
                        for (uint i = 0; i < NUM_AIRPORTTILES_PER_GRF; i++) {
                                if (airporttilespec[i] != nullptr && airporttilespec[i]->enabled) {
                                        _airporttile_mngr.SetEntitySpec(airporttilespec[i]);
                                }
                        }
                }
        }
}

/* Here we perform initial decoding of some special sprites (as are they
 * described at http://www.ttdpatch.net/src/newgrf.txt, but this is only a very
 * partial implementation yet).
 * XXX: We consider GRF files trusted. It would be trivial to exploit OTTD by
 * a crafted invalid GRF file. We should tell that to the user somehow, or
 * better make this more robust in the future. */
static void DecodeSpecialSprite(byte *buf, uint num, GrfLoadingStage stage)
{
        /* XXX: There is a difference between staged loading in TTDPatch and
         * here.  In TTDPatch, for some reason actions 1 and 2 are carried out
         * during stage 1, whilst action 3 is carried out during stage 2 (to
         * "resolve" cargo IDs... wtf). This is a little problem, because cargo
         * IDs are valid only within a given set (action 1) block, and may be
         * overwritten after action 3 associates them. But overwriting happens
         * in an earlier stage than associating, so...  We just process actions
         * 1 and 2 in stage 2 now, let's hope that won't get us into problems.
         * --pasky
         * We need a pre-stage to set up GOTO labels of Action 0x10 because the grf
         * is not in memory and scanning the file every time would be too expensive.
         * In other stages we skip action 0x10 since it's already dealt with. */
        static const SpecialSpriteHandler handlers[][GLS_END] = {
                /* 0x00 */ { nullptr,     SafeChangeInfo, nullptr,       nullptr,           ReserveChangeInfo, FeatureChangeInfo, },
                /* 0x01 */ { SkipAct1, SkipAct1,  SkipAct1,        SkipAct1,       SkipAct1,          NewSpriteSet, },
                /* 0x02 */ { nullptr,     nullptr,      nullptr,            nullptr,           nullptr,              NewSpriteGroup, },
                /* 0x03 */ { nullptr,     GRFUnsafe, nullptr,            nullptr,           nullptr,              FeatureMapSpriteGroup, },
                /* 0x04 */ { nullptr,     nullptr,      nullptr,            nullptr,           nullptr,              FeatureNewName, },
                /* 0x05 */ { SkipAct5, SkipAct5,  SkipAct5,        SkipAct5,       SkipAct5,          GraphicsNew, },
                /* 0x06 */ { nullptr,     nullptr,      nullptr,            CfgApply,       CfgApply,          CfgApply, },
                /* 0x07 */ { nullptr,     nullptr,      nullptr,            nullptr,           SkipIf,            SkipIf, },
                /* 0x08 */ { ScanInfo, nullptr,      nullptr,            GRFInfo,        GRFInfo,           GRFInfo, },
                /* 0x09 */ { nullptr,     nullptr,      nullptr,            SkipIf,         SkipIf,            SkipIf, },
                /* 0x0A */ { SkipActA, SkipActA,  SkipActA,        SkipActA,       SkipActA,          SpriteReplace, },
                /* 0x0B */ { nullptr,     nullptr,      nullptr,            GRFLoadError,   GRFLoadError,      GRFLoadError, },
                /* 0x0C */ { nullptr,     nullptr,      nullptr,            GRFComment,     nullptr,              GRFComment, },
                /* 0x0D */ { nullptr,     SafeParamSet, nullptr,         ParamSet,       ParamSet,          ParamSet, },
                /* 0x0E */ { nullptr,     SafeGRFInhibit, nullptr,       GRFInhibit,     GRFInhibit,        GRFInhibit, },
                /* 0x0F */ { nullptr,     GRFUnsafe, nullptr,            FeatureTownName, nullptr,             nullptr, },
                /* 0x10 */ { nullptr,     nullptr,      DefineGotoLabel, nullptr,           nullptr,              nullptr, },
                /* 0x11 */ { SkipAct11,GRFUnsafe, SkipAct11,       GRFSound,       SkipAct11,         GRFSound, },
                /* 0x12 */ { SkipAct12, SkipAct12, SkipAct12,      SkipAct12,      SkipAct12,         LoadFontGlyph, },
                /* 0x13 */ { nullptr,     nullptr,      nullptr,            nullptr,           nullptr,              TranslateGRFStrings, },
                /* 0x14 */ { StaticGRFInfo, nullptr, nullptr,            nullptr,           nullptr,              nullptr, },
        };

        GRFLocation location(_cur.grfconfig->ident.grfid, _cur.nfo_line);

        GRFLineToSpriteOverride::iterator it = _grf_line_to_action6_sprite_override.find(location);
        if (it == _grf_line_to_action6_sprite_override.end()) {
                /* No preloaded sprite to work with; read the
                 * pseudo sprite content. */
                FioReadBlock(buf, num);
        } else {
                /* Use the preloaded sprite data. */
                buf = it->second;
                grfmsg(7, "DecodeSpecialSprite: Using preloaded pseudo sprite data");

                /* Skip the real (original) content of this action. */
                FioSeekTo(num, SEEK_CUR);
        }

        ByteReader br(buf, buf + num);
        ByteReader *bufp = &br;

        try {
                byte action = bufp->ReadByte();

                if (action == 0xFF) {
                        grfmsg(2, "DecodeSpecialSprite: Unexpected data block, skipping");
                } else if (action == 0xFE) {
                        grfmsg(2, "DecodeSpecialSprite: Unexpected import block, skipping");
                } else if (action >= lengthof(handlers)) {
                        grfmsg(7, "DecodeSpecialSprite: Skipping unknown action 0x%02X", action);
                } else if (handlers[action][stage] == nullptr) {
                        grfmsg(7, "DecodeSpecialSprite: Skipping action 0x%02X in stage %d", action, stage);
                } else {
                        grfmsg(7, "DecodeSpecialSprite: Handling action 0x%02X in stage %d", action, stage);
                        handlers[action][stage](bufp);
                }
        } catch (...) {
                grfmsg(1, "DecodeSpecialSprite: Tried to read past end of pseudo-sprite data");
                DisableGrf(STR_NEWGRF_ERROR_READ_BOUNDS);
        }
}


/** Signature of a container version 2 GRF. */
extern const byte _grf_cont_v2_sig[8] = {'G', 'R', 'F', 0x82, 0x0D, 0x0A, 0x1A, 0x0A};

/**
 * Get the container version of the currently opened GRF file.
 * @return Container version of the GRF file or 0 if the file is corrupt/no GRF file.
 */
byte GetGRFContainerVersion()
{
        size_t pos = FioGetPos();

        if (FioReadWord() == 0) {
                /* Check for GRF container version 2, which is identified by the bytes
                 * '47 52 46 82 0D 0A 1A 0A' at the start of the file. */
                for (uint i = 0; i < lengthof(_grf_cont_v2_sig); i++) {
                        if (FioReadByte() != _grf_cont_v2_sig[i]) return 0; // Invalid format
                }

                return 2;
        }

        /* Container version 1 has no header, rewind to start. */
        FioSeekTo(pos, SEEK_SET);
        return 1;
}

/**
 * Load a particular NewGRF.
 * @param config     The configuration of the to be loaded NewGRF.
 * @param file_index The Fio index of the first NewGRF to load.
 * @param stage      The loading stage of the NewGRF.
 * @param subdir     The sub directory to find the NewGRF in.
 */
void LoadNewGRFFile(GRFConfig *config, uint file_index, GrfLoadingStage stage, Subdirectory subdir)
{
        const char *filename = config->filename;

        /* A .grf file is activated only if it was active when the game was
         * started.  If a game is loaded, only its active .grfs will be
         * reactivated, unless "loadallgraphics on" is used.  A .grf file is
         * considered active if its action 8 has been processed, i.e. its
         * action 8 hasn't been skipped using an action 7.
         *
         * During activation, only actions 0, 1, 2, 3, 4, 5, 7, 8, 9, 0A and 0B are
         * carried out.  All others are ignored, because they only need to be
         * processed once at initialization.  */
        if (stage != GLS_FILESCAN && stage != GLS_SAFETYSCAN && stage != GLS_LABELSCAN) {
                _cur.grffile = GetFileByFilename(filename);
                if (_cur.grffile == nullptr) usererror("File '%s' lost in cache.\n", filename);
                if (stage == GLS_RESERVE && config->status != GCS_INITIALISED) return;
                if (stage == GLS_ACTIVATION && !HasBit(config->flags, GCF_RESERVED)) return;
        }

        if (file_index >= MAX_FILE_SLOTS) {
                DEBUG(grf, 0, "'%s' is not loaded as the maximum number of file slots has been reached", filename);
                config->status = GCS_DISABLED;
                config->error  = new GRFError(STR_NEWGRF_ERROR_MSG_FATAL, STR_NEWGRF_ERROR_TOO_MANY_NEWGRFS_LOADED);
                return;
        }

        FioOpenFile(file_index, filename, subdir);
        _cur.file_index = file_index; // XXX
        _palette_remap_grf[_cur.file_index] = (config->palette & GRFP_USE_MASK);

        _cur.grfconfig = config;

        DEBUG(grf, 2, "LoadNewGRFFile: Reading NewGRF-file '%s'", filename);

        _cur.grf_container_ver = GetGRFContainerVersion();
        if (_cur.grf_container_ver == 0) {
                DEBUG(grf, 7, "LoadNewGRFFile: Custom .grf has invalid format");
                return;
        }

        if (stage == GLS_INIT || stage == GLS_ACTIVATION) {
                /* We need the sprite offsets in the init stage for NewGRF sounds
                 * and in the activation stage for real sprites. */
                ReadGRFSpriteOffsets(_cur.grf_container_ver);
        } else {
                /* Skip sprite section offset if present. */
                if (_cur.grf_container_ver >= 2) FioReadDword();
        }

        if (_cur.grf_container_ver >= 2) {
                /* Read compression value. */
                byte compression = FioReadByte();
                if (compression != 0) {
                        DEBUG(grf, 7, "LoadNewGRFFile: Unsupported compression format");
                        return;
                }
        }

        /* Skip the first sprite; we don't care about how many sprites this
         * does contain; newest TTDPatches and George's longvehicles don't
         * neither, apparently. */
        uint32 num = _cur.grf_container_ver >= 2 ? FioReadDword() : FioReadWord();
        if (num == 4 && FioReadByte() == 0xFF) {
                FioReadDword();
        } else {
                DEBUG(grf, 7, "LoadNewGRFFile: Custom .grf has invalid format");
                return;
        }

        _cur.ClearDataForNextFile();

        ReusableBuffer<byte> buf;

        while ((num = (_cur.grf_container_ver >= 2 ? FioReadDword() : FioReadWord())) != 0) {
                byte type = FioReadByte();
                _cur.nfo_line++;

                if (type == 0xFF) {
                        if (_cur.skip_sprites == 0) {
                                DecodeSpecialSprite(buf.Allocate(num), num, stage);

                                /* Stop all processing if we are to skip the remaining sprites */
                                if (_cur.skip_sprites == -1) break;

                                continue;
                        } else {
                                FioSkipBytes(num);
                        }
                } else {
                        if (_cur.skip_sprites == 0) {
                                grfmsg(0, "LoadNewGRFFile: Unexpected sprite, disabling");
                                DisableGrf(STR_NEWGRF_ERROR_UNEXPECTED_SPRITE);
                                break;
                        }

                        if (_cur.grf_container_ver >= 2 && type == 0xFD) {
                                /* Reference to data section. Container version >= 2 only. */
                                FioSkipBytes(num);
                        } else {
                                FioSkipBytes(7);
                                SkipSpriteData(type, num - 8);
                        }
                }

                if (_cur.skip_sprites > 0) _cur.skip_sprites--;
        }
}

/**
 * Relocates the old shore sprites at new positions.
 *
 * 1. If shore sprites are neither loaded by Action5 nor ActionA, the extra sprites from openttd(w/d).grf are used. (SHORE_REPLACE_ONLY_NEW)
 * 2. If a newgrf replaces some shore sprites by ActionA. The (maybe also replaced) grass tiles are used for corner shores. (SHORE_REPLACE_ACTION_A)
 * 3. If a newgrf replaces shore sprites by Action5 any shore replacement by ActionA has no effect. (SHORE_REPLACE_ACTION_5)
 */
static void ActivateOldShore()
{
        /* Use default graphics, if no shore sprites were loaded.
         * Should not happen, as the base set's extra grf should include some. */
        if (_loaded_newgrf_features.shore == SHORE_REPLACE_NONE) _loaded_newgrf_features.shore = SHORE_REPLACE_ACTION_A;

        if (_loaded_newgrf_features.shore != SHORE_REPLACE_ACTION_5) {
                DupSprite(SPR_ORIGINALSHORE_START +  1, SPR_SHORE_BASE +  1); // SLOPE_W
                DupSprite(SPR_ORIGINALSHORE_START +  2, SPR_SHORE_BASE +  2); // SLOPE_S
                DupSprite(SPR_ORIGINALSHORE_START +  6, SPR_SHORE_BASE +  3); // SLOPE_SW
                DupSprite(SPR_ORIGINALSHORE_START +  0, SPR_SHORE_BASE +  4); // SLOPE_E
                DupSprite(SPR_ORIGINALSHORE_START +  4, SPR_SHORE_BASE +  6); // SLOPE_SE
                DupSprite(SPR_ORIGINALSHORE_START +  3, SPR_SHORE_BASE +  8); // SLOPE_N
                DupSprite(SPR_ORIGINALSHORE_START +  7, SPR_SHORE_BASE +  9); // SLOPE_NW
                DupSprite(SPR_ORIGINALSHORE_START +  5, SPR_SHORE_BASE + 12); // SLOPE_NE
        }

        if (_loaded_newgrf_features.shore == SHORE_REPLACE_ACTION_A) {
                DupSprite(SPR_FLAT_GRASS_TILE + 16, SPR_SHORE_BASE +  0); // SLOPE_STEEP_S
                DupSprite(SPR_FLAT_GRASS_TILE + 17, SPR_SHORE_BASE +  5); // SLOPE_STEEP_W
                DupSprite(SPR_FLAT_GRASS_TILE +  7, SPR_SHORE_BASE +  7); // SLOPE_WSE
                DupSprite(SPR_FLAT_GRASS_TILE + 15, SPR_SHORE_BASE + 10); // SLOPE_STEEP_N
                DupSprite(SPR_FLAT_GRASS_TILE + 11, SPR_SHORE_BASE + 11); // SLOPE_NWS
                DupSprite(SPR_FLAT_GRASS_TILE + 13, SPR_SHORE_BASE + 13); // SLOPE_ENW
                DupSprite(SPR_FLAT_GRASS_TILE + 14, SPR_SHORE_BASE + 14); // SLOPE_SEN
                DupSprite(SPR_FLAT_GRASS_TILE + 18, SPR_SHORE_BASE + 15); // SLOPE_STEEP_E

                /* XXX - SLOPE_EW, SLOPE_NS are currently not used.
                 *       If they would be used somewhen, then these grass tiles will most like not look as needed */
                DupSprite(SPR_FLAT_GRASS_TILE +  5, SPR_SHORE_BASE + 16); // SLOPE_EW
                DupSprite(SPR_FLAT_GRASS_TILE + 10, SPR_SHORE_BASE + 17); // SLOPE_NS
        }
}

/**
 * Replocate the old tram depot sprites to the new position, if no new ones were loaded.
 */
static void ActivateOldTramDepot()
{
        if (_loaded_newgrf_features.tram == TRAMWAY_REPLACE_DEPOT_WITH_TRACK) {
                DupSprite(SPR_ROAD_DEPOT               + 0, SPR_TRAMWAY_DEPOT_NO_TRACK + 0); // use road depot graphics for "no tracks"
                DupSprite(SPR_TRAMWAY_DEPOT_WITH_TRACK + 1, SPR_TRAMWAY_DEPOT_NO_TRACK + 1);
                DupSprite(SPR_ROAD_DEPOT               + 2, SPR_TRAMWAY_DEPOT_NO_TRACK + 2); // use road depot graphics for "no tracks"
                DupSprite(SPR_TRAMWAY_DEPOT_WITH_TRACK + 3, SPR_TRAMWAY_DEPOT_NO_TRACK + 3);
                DupSprite(SPR_TRAMWAY_DEPOT_WITH_TRACK + 4, SPR_TRAMWAY_DEPOT_NO_TRACK + 4);
                DupSprite(SPR_TRAMWAY_DEPOT_WITH_TRACK + 5, SPR_TRAMWAY_DEPOT_NO_TRACK + 5);
        }
}

/**
 * Decide whether price base multipliers of grfs shall apply globally or only to the grf specifying them
 */
static void FinalisePriceBaseMultipliers()
{
        extern const PriceBaseSpec _price_base_specs[];
        /** Features, to which '_grf_id_overrides' applies. Currently vehicle features only. */
        static const uint32 override_features = (1 << GSF_TRAINS) | (1 << GSF_ROADVEHICLES) | (1 << GSF_SHIPS) | (1 << GSF_AIRCRAFT);

        /* Evaluate grf overrides */
        int num_grfs = _grf_files.Length();
        int *grf_overrides = AllocaM(int, num_grfs);
        for (int i = 0; i < num_grfs; i++) {
                grf_overrides[i] = -1;

                GRFFile *source = _grf_files[i];
                uint32 override = _grf_id_overrides[source->grfid];
                if (override == 0) continue;

                GRFFile *dest = GetFileByGRFID(override);
                if (dest == nullptr) continue;

                grf_overrides[i] = _grf_files.FindIndex(dest);
                assert(grf_overrides[i] >= 0);
        }

        /* Override features and price base multipliers of earlier loaded grfs */
        for (int i = 0; i < num_grfs; i++) {
                if (grf_overrides[i] < 0 || grf_overrides[i] >= i) continue;
                GRFFile *source = _grf_files[i];
                GRFFile *dest = _grf_files[grf_overrides[i]];

                uint32 features = (source->grf_features | dest->grf_features) & override_features;
                source->grf_features |= features;
                dest->grf_features |= features;

                for (Price p = PR_BEGIN; p < PR_END; p++) {
                        /* No price defined -> nothing to do */
                        if (!HasBit(features, _price_base_specs[p].grf_feature) || source->price_base_multipliers[p] == INVALID_PRICE_MODIFIER) continue;
                        DEBUG(grf, 3, "'%s' overrides price base multiplier %d of '%s'", source->filename, p, dest->filename);
                        dest->price_base_multipliers[p] = source->price_base_multipliers[p];
                }
        }

        /* Propagate features and price base multipliers of afterwards loaded grfs, if none is present yet */
        for (int i = num_grfs - 1; i >= 0; i--) {
                if (grf_overrides[i] < 0 || grf_overrides[i] <= i) continue;
                GRFFile *source = _grf_files[i];
                GRFFile *dest = _grf_files[grf_overrides[i]];

                uint32 features = (source->grf_features | dest->grf_features) & override_features;
                source->grf_features |= features;
                dest->grf_features |= features;

                for (Price p = PR_BEGIN; p < PR_END; p++) {
                        /* Already a price defined -> nothing to do */
                        if (!HasBit(features, _price_base_specs[p].grf_feature) || dest->price_base_multipliers[p] != INVALID_PRICE_MODIFIER) continue;
                        DEBUG(grf, 3, "Price base multiplier %d from '%s' propagated to '%s'", p, source->filename, dest->filename);
                        dest->price_base_multipliers[p] = source->price_base_multipliers[p];
                }
        }

        /* The 'master grf' now have the correct multipliers. Assign them to the 'addon grfs' to make everything consistent. */
        for (int i = 0; i < num_grfs; i++) {
                if (grf_overrides[i] < 0) continue;
                GRFFile *source = _grf_files[i];
                GRFFile *dest = _grf_files[grf_overrides[i]];

                uint32 features = (source->grf_features | dest->grf_features) & override_features;
                source->grf_features |= features;
                dest->grf_features |= features;

                for (Price p = PR_BEGIN; p < PR_END; p++) {
                        if (!HasBit(features, _price_base_specs[p].grf_feature)) continue;
                        if (source->price_base_multipliers[p] != dest->price_base_multipliers[p]) {
                                DEBUG(grf, 3, "Price base multiplier %d from '%s' propagated to '%s'", p, dest->filename, source->filename);
                        }
                        source->price_base_multipliers[p] = dest->price_base_multipliers[p];
                }
        }

        /* Apply fallback prices for grf version < 8 */
        const GRFFile * const *end = _grf_files.End();
        for (GRFFile **file = _grf_files.Begin(); file != end; file++) {
                if ((*file)->grf_version >= 8) continue;
                PriceMultipliers &price_base_multipliers = (*file)->price_base_multipliers;
                for (Price p = PR_BEGIN; p < PR_END; p++) {
                        Price fallback_price = _price_base_specs[p].fallback_price;
                        if (fallback_price != INVALID_PRICE && price_base_multipliers[p] == INVALID_PRICE_MODIFIER) {
                                /* No price multiplier has been set.
                                 * So copy the multiplier from the fallback price, maybe a multiplier was set there. */
                                price_base_multipliers[p] = price_base_multipliers[fallback_price];
                        }
                }
        }

        /* Decide local/global scope of price base multipliers */
        for (GRFFile **file = _grf_files.Begin(); file != end; file++) {
                PriceMultipliers &price_base_multipliers = (*file)->price_base_multipliers;
                for (Price p = PR_BEGIN; p < PR_END; p++) {
                        if (price_base_multipliers[p] == INVALID_PRICE_MODIFIER) {
                                /* No multiplier was set; set it to a neutral value */
                                price_base_multipliers[p] = 0;
                        } else {
                                if (!HasBit((*file)->grf_features, _price_base_specs[p].grf_feature)) {
                                        /* The grf does not define any objects of the feature,
                                         * so it must be a difficulty setting. Apply it globally */
                                        DEBUG(grf, 3, "'%s' sets global price base multiplier %d", (*file)->filename, p);
                                        SetPriceBaseMultiplier(p, price_base_multipliers[p]);
                                        price_base_multipliers[p] = 0;
                                } else {
                                        DEBUG(grf, 3, "'%s' sets local price base multiplier %d", (*file)->filename, p);
                                }
                        }
                }
        }
}

extern void InitGRFTownGeneratorNames();

/** Finish loading NewGRFs and execute needed post-processing */
static void AfterLoadGRFs()
{
        for (StringIDMapping *it = _string_to_grf_mapping.Begin(); it != _string_to_grf_mapping.End(); it++) {
                *it->target = MapGRFStringID(it->grfid, it->source);
        }
        _string_to_grf_mapping.Clear();

        /* Free the action 6 override sprites. */
        for (GRFLineToSpriteOverride::iterator it = _grf_line_to_action6_sprite_override.begin(); it != _grf_line_to_action6_sprite_override.end(); it++) {
                free((*it).second);
        }
        _grf_line_to_action6_sprite_override.clear();

        /* Polish cargoes */
        FinaliseCargoArray();

        /* Pre-calculate all refit masks after loading GRF files. */
        CalculateRefitMasks();

        /* Polish engines */
        FinaliseEngineArray();

        /* Set the actually used Canal properties */
        FinaliseCanals();

        /* Add all new houses to the house array. */
        FinaliseHouseArray();

        /* Add all new industries to the industry array. */
        FinaliseIndustriesArray();

        /* Add all new objects to the object array. */
        FinaliseObjectsArray();

        InitializeSortedCargoSpecs();

        /* Sort the list of industry types. */
        SortIndustryTypes();

        /* Create dynamic list of industry legends for smallmap_gui.cpp */
        BuildIndustriesLegend();

        /* Build the routemap legend, based on the available cargos */
        BuildLinkStatsLegend();

        /* Add all new airports to the airports array. */
        FinaliseAirportsArray();
        BindAirportSpecs();

        /* Update the townname generators list */
        InitGRFTownGeneratorNames();

        /* Run all queued vehicle list order changes */
        CommitVehicleListOrderChanges();

        /* Load old shore sprites in new position, if they were replaced by ActionA */
        ActivateOldShore();

        /* Load old tram depot sprites in new position, if no new ones are present */
        ActivateOldTramDepot();

        /* Set up custom rail types */
        InitRailTypes();
        InitRoadTypes();

        Engine *e;
        FOR_ALL_ENGINES_OF_TYPE(e, VEH_ROAD) {
                RoadType rt = HasBit(e->info.misc_flags, EF_ROAD_TRAM) ? ROADTYPE_TRAM : ROADTYPE_ROAD;
                const GRFFile *file = e->GetGRF();
                if (file != NULL && _gted[e->index].roadsubtype < file->roadtype_list[rt].Length()) {
                        RoadTypeIdentifier rtid = GetRoadTypeByLabel(file->roadtype_list[rt][_gted[e->index].roadsubtype], rt, true);
                        if (rtid.IsValid()) {
                                e->u.road.roadsubtype = rtid.subtype;
                        } else {
                                /* Road type is not available, so disable this engine */
                                e->info.climates = 0;
                        }
                } else {
                        e->u.road.roadsubtype = rt == ROADTYPE_TRAM ? ROADSUBTYPE_ELECTRIC : ROADSUBTYPE_NORMAL;
                }

                if (_gted[e->index].rv_max_speed != 0) {
                        /* Set RV maximum speed from the mph/0.8 unit value */
                        e->u.road.max_speed = _gted[e->index].rv_max_speed * 4;
                }
        }

        FOR_ALL_ENGINES_OF_TYPE(e, VEH_TRAIN) {
                RailType railtype = GetRailTypeByLabel(_gted[e->index].railtypelabel);
                if (railtype == INVALID_RAILTYPE) {
                        /* Rail type is not available, so disable this engine */
                        e->info.climates = 0;
                } else {
                        e->u.rail.railtype = railtype;
                }
        }

        SetYearEngineAgingStops();

        FinalisePriceBaseMultipliers();

        /* Deallocate temporary loading data */
        free(_gted);
        _grm_sprites.clear();
}

/**
 * Load all the NewGRFs.
 * @param load_index The offset for the first sprite to add.
 * @param file_index The Fio index of the first NewGRF to load.
 * @param num_baseset Number of NewGRFs at the front of the list to look up in the baseset dir instead of the newgrf dir.
 */
void LoadNewGRF(uint load_index, uint file_index, uint num_baseset)
{
        /* In case of networking we need to "sync" the start values
         * so all NewGRFs are loaded equally. For this we use the
         * start date of the game and we set the counters, etc. to
         * 0 so they're the same too. */
        Date date            = _date;
        Year year            = _cur_year;
        DateFract date_fract = _date_fract;
        uint16 tick_counter  = _tick_counter;
        byte display_opt     = _display_opt;

        if (_networking) {
                _cur_year     = _settings_game.game_creation.starting_year;
                _date         = ConvertYMDToDate(_cur_year, 0, 1);
                _date_fract   = 0;
                _tick_counter = 0;
                _display_opt  = 0;
        }

        InitializeGRFSpecial();

        ResetNewGRFData();

        /*
         * Reset the status of all files, so we can 'retry' to load them.
         * This is needed when one for example rearranges the NewGRFs in-game
         * and a previously disabled NewGRF becomes useable. If it would not
         * be reset, the NewGRF would remain disabled even though it should
         * have been enabled.
         */
        for (GRFConfig *c = _grfconfig; c != nullptr; c = c->next) {
                if (c->status != GCS_NOT_FOUND) c->status = GCS_UNKNOWN;
        }

        _cur.spriteid = load_index;

        /* Load newgrf sprites
         * in each loading stage, (try to) open each file specified in the config
         * and load information from it. */
        for (GrfLoadingStage stage = GLS_LABELSCAN; stage <= GLS_ACTIVATION; stage++) {
                /* Set activated grfs back to will-be-activated between reservation- and activation-stage.
                 * This ensures that action7/9 conditions 0x06 - 0x0A work correctly. */
                for (GRFConfig *c = _grfconfig; c != nullptr; c = c->next) {
                        if (c->status == GCS_ACTIVATED) c->status = GCS_INITIALISED;
                }

                if (stage == GLS_RESERVE) {
                        static const uint32 overrides[][2] = {
                                { 0x44442202, 0x44440111 }, // UKRS addons modifies UKRS
                                { 0x6D620402, 0x6D620401 }, // DBSetXL ECS extension modifies DBSetXL
                                { 0x4D656f20, 0x4D656F17 }, // LV4cut modifies LV4
                        };
                        for (size_t i = 0; i < lengthof(overrides); i++) {
                                SetNewGRFOverride(BSWAP32(overrides[i][0]), BSWAP32(overrides[i][1]));
                        }
                }

                uint slot = file_index;
                uint num_non_static = 0;

                _cur.stage = stage;
                for (GRFConfig *c = _grfconfig; c != nullptr; c = c->next) {
                        if (c->status == GCS_DISABLED || c->status == GCS_NOT_FOUND) continue;
                        if (stage > GLS_INIT && HasBit(c->flags, GCF_INIT_ONLY)) continue;

                        Subdirectory subdir = slot < file_index + num_baseset ? BASESET_DIR : NEWGRF_DIR;
                        if (!FioCheckFileExists(c->filename, subdir)) {
                                DEBUG(grf, 0, "NewGRF file is missing '%s'; disabling", c->filename);
                                c->status = GCS_NOT_FOUND;
                                continue;
                        }

                        if (stage == GLS_LABELSCAN) InitNewGRFFile(c);

                        if (!HasBit(c->flags, GCF_STATIC) && !HasBit(c->flags, GCF_SYSTEM)) {
                                if (slot == MAX_FILE_SLOTS) {
                                        DEBUG(grf, 0, "'%s' is not loaded as the maximum number of non-static GRFs has been reached", c->filename);
                                        c->status = GCS_DISABLED;
                                        c->error  = new GRFError(STR_NEWGRF_ERROR_MSG_FATAL, STR_NEWGRF_ERROR_TOO_MANY_NEWGRFS_LOADED);
                                        continue;
                                }
                                num_non_static++;
                        }
                        LoadNewGRFFile(c, slot++, stage, subdir);
                        if (stage == GLS_RESERVE) {
                                SetBit(c->flags, GCF_RESERVED);
                        } else if (stage == GLS_ACTIVATION) {
                                ClrBit(c->flags, GCF_RESERVED);
                                assert(GetFileByGRFID(c->ident.grfid) == _cur.grffile);
                                ClearTemporaryNewGRFData(_cur.grffile);
                                BuildCargoTranslationMap();
                                DEBUG(sprite, 2, "LoadNewGRF: Currently %i sprites are loaded", _cur.spriteid);
                        } else if (stage == GLS_INIT && HasBit(c->flags, GCF_INIT_ONLY)) {
                                /* We're not going to activate this, so free whatever data we allocated */
                                ClearTemporaryNewGRFData(_cur.grffile);
                        }
                }
        }

        /* Pseudo sprite processing is finished; free temporary stuff */
        _cur.ClearDataForNextFile();

        /* Call any functions that should be run after GRFs have been loaded. */
        AfterLoadGRFs();

        /* Now revert back to the original situation */
        _cur_year     = year;
        _date         = date;
        _date_fract   = date_fract;
        _tick_counter = tick_counter;
        _display_opt  = display_opt;
}

/**
 * Returns amount of user selected NewGRFs files.
 */
uint CountSelectedGRFs(GRFConfig *grfconf)
{
        uint i = 0;

        /* Find last entry in the list */
        for (const GRFConfig *list = grfconf; list != nullptr; list = list->next) {
                if (!HasBit(list->flags, GCF_STATIC) && !HasBit(list->flags, GCF_SYSTEM)) i++;
        }
        return i;
}