Update: Translations from eints

[openttd-github.git] / src / smallmap_gui.cpp

/*
 * 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 smallmap_gui.cpp GUI that shows a small map of the world with metadata like owner or height. */

#include "stdafx.h"
#include "core/backup_type.hpp"
#include "clear_map.h"
#include "industry.h"
#include "station_map.h"
#include "landscape.h"
#include "tree_map.h"
#include "viewport_func.h"
#include "town.h"
#include "tunnelbridge_map.h"
#include "core/endian_func.hpp"
#include "vehicle_base.h"
#include "sound_func.h"
#include "window_func.h"
#include "company_base.h"
#include "zoom_func.h"
#include "strings_func.h"
#include "blitter/factory.hpp"
#include "linkgraph/linkgraph_gui.h"
#include "timer/timer.h"
#include "timer/timer_window.h"
#include "smallmap_gui.h"

#include "widgets/smallmap_widget.h"

#include "table/strings.h"

#include <bitset>

#include "safeguards.h"

static int _smallmap_industry_count; ///< Number of used industries
static int _smallmap_company_count;  ///< Number of entries in the owner legend.
static int _smallmap_cargo_count;    ///< Number of cargos in the link stats legend.

/** Structure for holding relevant data for legends in small map */
struct LegendAndColour {
        uint8_t colour;            ///< Colour of the item on the map.
        StringID legend;           ///< String corresponding to the coloured item.
        IndustryType type;         ///< Type of industry. Only valid for industry entries.
        uint8_t height;            ///< Height in tiles. Only valid for height legend entries.
        CompanyID company;         ///< Company to display. Only valid for company entries of the owner legend.
        bool show_on_map;          ///< For filtering industries, if \c true, industry is shown on the map in colour.
        bool end;                  ///< This is the end of the list.
        bool col_break;            ///< Perform a column break and go further at the next column.
};

/** Link stat colours shown in legenda. */
static uint8_t _linkstat_colours_in_legenda[] = {0, 1, 3, 5, 7, 9, 11};

static const int NUM_NO_COMPANY_ENTRIES = 4; ///< Number of entries in the owner legend that are not companies.

/** Macro for ordinary entry of LegendAndColour */
#define MK(a, b) {a, b, INVALID_INDUSTRYTYPE, 0, INVALID_COMPANY, true, false, false}

/** Macro for a height legend entry with configurable colour. */
#define MC(col_break)  {0, STR_TINY_BLACK_HEIGHT, INVALID_INDUSTRYTYPE, 0, INVALID_COMPANY, true, false, col_break}

/** Macro for non-company owned property entry of LegendAndColour */
#define MO(a, b) {a, b, INVALID_INDUSTRYTYPE, 0, INVALID_COMPANY, true, false, false}

/** Macro used for forcing a rebuild of the owner legend the first time it is used. */
#define MOEND() {0, 0, INVALID_INDUSTRYTYPE, 0, OWNER_NONE, true, true, false}

/** Macro for end of list marker in arrays of LegendAndColour */
#define MKEND() {0, STR_NULL, INVALID_INDUSTRYTYPE, 0, INVALID_COMPANY, true, true, false}

/**
 * Macro for break marker in arrays of LegendAndColour.
 * It will have valid data, though
 */
#define MS(a, b) {a, b, INVALID_INDUSTRYTYPE, 0, INVALID_COMPANY, true, false, true}

/** Legend text giving the colours to look for on the minimap */
static LegendAndColour _legend_land_contours[] = {
        MK(PC_BLACK,           STR_SMALLMAP_LEGENDA_ROADS),
        MK(PC_GREY,            STR_SMALLMAP_LEGENDA_RAILROADS),
        MK(PC_LIGHT_BLUE,      STR_SMALLMAP_LEGENDA_STATIONS_AIRPORTS_DOCKS),
        MK(PC_DARK_RED,        STR_SMALLMAP_LEGENDA_BUILDINGS_INDUSTRIES),
        MK(PC_WHITE,           STR_SMALLMAP_LEGENDA_VEHICLES),

        /* Placeholders for the colours and heights of the legend.
         * The following values are set at BuildLandLegend() based
         * on each colour scheme and the maximum map height. */
        MC(true),
        MC(false),
        MC(false),
        MC(false),
        MC(false),
        MC(false),
        MC(true),
        MC(false),
        MC(false),
        MC(false),
        MC(false),
        MC(false),
        MKEND()
};

static const LegendAndColour _legend_vehicles[] = {
        MK(PC_RED,             STR_SMALLMAP_LEGENDA_TRAINS),
        MK(PC_YELLOW,          STR_SMALLMAP_LEGENDA_ROAD_VEHICLES),
        MK(PC_LIGHT_BLUE,      STR_SMALLMAP_LEGENDA_SHIPS),
        MK(PC_WHITE,           STR_SMALLMAP_LEGENDA_AIRCRAFT),

        MS(PC_BLACK,           STR_SMALLMAP_LEGENDA_TRANSPORT_ROUTES),
        MK(PC_DARK_RED,        STR_SMALLMAP_LEGENDA_BUILDINGS_INDUSTRIES),
        MKEND()
};

static const LegendAndColour _legend_routes[] = {
        MK(PC_BLACK,           STR_SMALLMAP_LEGENDA_ROADS),
        MK(PC_GREY,            STR_SMALLMAP_LEGENDA_RAILROADS),
        MK(PC_DARK_RED,        STR_SMALLMAP_LEGENDA_BUILDINGS_INDUSTRIES),

        MS(PC_VERY_DARK_BROWN, STR_SMALLMAP_LEGENDA_RAILROAD_STATION),
        MK(PC_ORANGE,          STR_SMALLMAP_LEGENDA_TRUCK_LOADING_BAY),
        MK(PC_YELLOW,          STR_SMALLMAP_LEGENDA_BUS_STATION),
        MK(PC_RED,             STR_SMALLMAP_LEGENDA_AIRPORT_HELIPORT),
        MK(PC_LIGHT_BLUE,      STR_SMALLMAP_LEGENDA_DOCK),
        MKEND()
};

static const LegendAndColour _legend_vegetation[] = {
        MK(PC_ROUGH_LAND,      STR_SMALLMAP_LEGENDA_ROUGH_LAND),
        MK(PC_GRASS_LAND,      STR_SMALLMAP_LEGENDA_GRASS_LAND),
        MK(PC_BARE_LAND,       STR_SMALLMAP_LEGENDA_BARE_LAND),
        MK(PC_RAINFOREST,      STR_SMALLMAP_LEGENDA_RAINFOREST),
        MK(PC_FIELDS,          STR_SMALLMAP_LEGENDA_FIELDS),
        MK(PC_TREES,           STR_SMALLMAP_LEGENDA_TREES),

        MS(PC_GREEN,           STR_SMALLMAP_LEGENDA_FOREST),
        MK(PC_GREY,            STR_SMALLMAP_LEGENDA_ROCKS),
        MK(PC_ORANGE,          STR_SMALLMAP_LEGENDA_DESERT),
        MK(PC_LIGHT_BLUE,      STR_SMALLMAP_LEGENDA_SNOW),
        MK(PC_BLACK,           STR_SMALLMAP_LEGENDA_TRANSPORT_ROUTES),
        MK(PC_DARK_RED,        STR_SMALLMAP_LEGENDA_BUILDINGS_INDUSTRIES),
        MKEND()
};

static LegendAndColour _legend_land_owners[NUM_NO_COMPANY_ENTRIES + MAX_COMPANIES + 1] = {
        MO(PC_WATER,           STR_SMALLMAP_LEGENDA_WATER),
        MO(0x00,               STR_SMALLMAP_LEGENDA_NO_OWNER), // This colour will vary depending on settings.
        MO(PC_DARK_RED,        STR_SMALLMAP_LEGENDA_TOWNS),
        MO(PC_DARK_GREY,       STR_SMALLMAP_LEGENDA_INDUSTRIES),
        /* The legend will be terminated the first time it is used. */
        MOEND(),
};

#undef MK
#undef MC
#undef MS
#undef MO
#undef MOEND
#undef MKEND

/** Legend entries for the link stats view. */
static LegendAndColour _legend_linkstats[NUM_CARGO + lengthof(_linkstat_colours_in_legenda) + 1];
/**
 * Allow room for all industries, plus a terminator entry
 * This is required in order to have the industry slots all filled up
 */
static LegendAndColour _legend_from_industries[NUM_INDUSTRYTYPES + 1];
/** For connecting industry type to position in industries list(small map legend) */
static uint _industry_to_list_pos[NUM_INDUSTRYTYPES];
/** The string bounding box width for each industry type in the smallmap */
static uint16_t _industry_to_name_string_width[NUM_INDUSTRYTYPES];
/** Show heightmap in industry and owner mode of smallmap window. */
static bool _smallmap_show_heightmap = false;
/** Highlight a specific industry type */
static IndustryType _smallmap_industry_highlight = INVALID_INDUSTRYTYPE;
/** State of highlight blinking */
static bool _smallmap_industry_highlight_state;
/** For connecting company ID to position in owner list (small map legend) */
static uint _company_to_list_pos[MAX_COMPANIES];

/**
 * Fills an array for the industries legends.
 */
void BuildIndustriesLegend()
{
        uint j = 0;

        /* Add each name */
        for (IndustryType ind : _sorted_industry_types) {
                const IndustrySpec *indsp = GetIndustrySpec(ind);
                if (indsp->enabled) {
                        _legend_from_industries[j].legend = indsp->name;
                        _legend_from_industries[j].colour = indsp->map_colour;
                        _legend_from_industries[j].type = ind;
                        _legend_from_industries[j].show_on_map = true;
                        _legend_from_industries[j].col_break = false;
                        _legend_from_industries[j].end = false;

                        /* Store widget number for this industry type. */
                        _industry_to_list_pos[ind] = j;
                        j++;
                }
        }
        /* Terminate the list */
        _legend_from_industries[j].end = true;

        /* Store number of enabled industries */
        _smallmap_industry_count = j;
}

/**
 * Populate legend table for the link stat view.
 */
void BuildLinkStatsLegend()
{
        /* Clear the legend */
        memset(_legend_linkstats, 0, sizeof(_legend_linkstats));

        uint i = 0;
        for (; i < _sorted_cargo_specs.size(); ++i) {
                const CargoSpec *cs = _sorted_cargo_specs[i];

                _legend_linkstats[i].legend = cs->name;
                _legend_linkstats[i].colour = cs->legend_colour;
                _legend_linkstats[i].type = cs->Index();
                _legend_linkstats[i].show_on_map = true;
        }

        _legend_linkstats[i].col_break = true;
        _smallmap_cargo_count = i;

        for (; i < _smallmap_cargo_count + lengthof(_linkstat_colours_in_legenda); ++i) {
                _legend_linkstats[i].legend = STR_EMPTY;
                _legend_linkstats[i].colour = LinkGraphOverlay::LINK_COLOURS[_settings_client.gui.linkgraph_colours][_linkstat_colours_in_legenda[i - _smallmap_cargo_count]];
                _legend_linkstats[i].show_on_map = true;
        }

        _legend_linkstats[_smallmap_cargo_count].legend = STR_LINKGRAPH_LEGEND_UNUSED;
        _legend_linkstats[i - 1].legend = STR_LINKGRAPH_LEGEND_OVERLOADED;
        _legend_linkstats[(_smallmap_cargo_count + i - 1) / 2].legend = STR_LINKGRAPH_LEGEND_SATURATED;
        _legend_linkstats[i].end = true;
}

static const LegendAndColour * const _legend_table[] = {
        _legend_land_contours,
        _legend_vehicles,
        _legend_from_industries,
        _legend_linkstats,
        _legend_routes,
        _legend_vegetation,
        _legend_land_owners,
};

#define MKCOLOUR(x)         TO_LE32X(x)

#define MKCOLOUR_XXXX(x)    (MKCOLOUR(0x01010101) * (uint)(x))
#define MKCOLOUR_0XX0(x)    (MKCOLOUR(0x00010100) * (uint)(x))
#define MKCOLOUR_X00X(x)    (MKCOLOUR(0x01000001) * (uint)(x))

#define MKCOLOUR_XYYX(x, y) (MKCOLOUR_X00X(x) | MKCOLOUR_0XX0(y))

#define MKCOLOUR_0000       MKCOLOUR_XXXX(0x00)
#define MKCOLOUR_F00F       MKCOLOUR_X00X(0xFF)
#define MKCOLOUR_FFFF       MKCOLOUR_XXXX(0xFF)

#include "table/heightmap_colours.h"

/** Colour scheme of the smallmap. */
struct SmallMapColourScheme {
        std::vector<uint32_t> height_colours; ///< Cached colours for each level in a map.
        std::span<const uint32_t> height_colours_base; ///< Base table for determining the colours
        uint32_t default_colour;             ///< Default colour of the land.
};

/** Available colour schemes for height maps. */
static SmallMapColourScheme _heightmap_schemes[] = {
        {{}, _green_map_heights,      MKCOLOUR_XXXX(0x54)}, ///< Green colour scheme.
        {{}, _dark_green_map_heights, MKCOLOUR_XXXX(0x62)}, ///< Dark green colour scheme.
        {{}, _violet_map_heights,     MKCOLOUR_XXXX(0x81)}, ///< Violet colour scheme.
};

/**
 * (Re)build the colour tables for the legends.
 */
void BuildLandLegend()
{
        /* The smallmap window has never been initialized, so no need to change the legend. */
        if (_heightmap_schemes[0].height_colours.empty()) return;

        /*
         * The general idea of this function is to fill the legend with an appropriate evenly spaced
         * selection of height levels. All entries with STR_TINY_BLACK_HEIGHT are reserved for this.
         * At the moment there are twelve of these.
         *
         * The table below defines up to which height level a particular delta in the legend should be
         * used. One could opt for just dividing the maximum height and use that as delta, but that
         * creates many "ugly" legend labels, e.g. once every 950 meter. As a result, this table will
         * reduce the number of deltas to 7: every 100m, 200m, 300m, 500m, 750m, 1000m and 1250m. The
         * deltas are closer together at the lower numbers because going from 12 entries to just 4, as
         * would happen when replacing 200m and 300m by 250m, would mean the legend would be short and
         * that might not be considered appropriate.
         *
         * The current method yields at least 7 legend entries and at most 12. It can be increased to
         * 8 by adding a 150m and 400m option, but especially 150m creates ugly heights.
         *
         * It tries to evenly space the legend items over the two columns that are there for the legend.
         */

        /* Table for delta; if max_height is less than the first column, use the second column as value. */
        uint deltas[][2] = { { 24, 2 }, { 48, 4 }, { 72, 6 }, { 120, 10 }, { 180, 15 }, { 240, 20 }, { MAX_TILE_HEIGHT + 1, 25 }};
        uint i = 0;
        for (; _settings_game.construction.map_height_limit >= deltas[i][0]; i++) {
                /* Nothing to do here. */
        }
        uint delta = deltas[i][1];

        int total_entries = (_settings_game.construction.map_height_limit / delta) + 1;
        int rows = CeilDiv(total_entries, 2);
        int j = 0;

        for (i = 0; i < lengthof(_legend_land_contours) - 1 && j < total_entries; i++) {
                if (_legend_land_contours[i].legend != STR_TINY_BLACK_HEIGHT) continue;

                _legend_land_contours[i].col_break = j % rows == 0;
                _legend_land_contours[i].end = false;
                _legend_land_contours[i].height = j * delta;
                _legend_land_contours[i].colour = _heightmap_schemes[_settings_client.gui.smallmap_land_colour].height_colours[j * delta];
                j++;
        }
        _legend_land_contours[i].end = true;
}

/**
 * Completes the array for the owned property legend.
 */
void BuildOwnerLegend()
{
        _legend_land_owners[1].colour = _heightmap_schemes[_settings_client.gui.smallmap_land_colour].default_colour;

        int i = NUM_NO_COMPANY_ENTRIES;
        for (const Company *c : Company::Iterate()) {
                _legend_land_owners[i].colour = GetColourGradient(c->colour, SHADE_LIGHT);
                _legend_land_owners[i].company = c->index;
                _legend_land_owners[i].show_on_map = true;
                _legend_land_owners[i].col_break = false;
                _legend_land_owners[i].end = false;
                _company_to_list_pos[c->index] = i;
                i++;
        }

        /* Terminate the list */
        _legend_land_owners[i].end = true;

        /* Store maximum amount of owner legend entries. */
        _smallmap_company_count = i;
}

struct AndOr {
        uint32_t mor;
        uint32_t mand;
};

static inline uint32_t ApplyMask(uint32_t colour, const AndOr *mask)
{
        return (colour & mask->mand) | mask->mor;
}


/** Colour masks for "Contour" and "Routes" modes. */
static const AndOr _smallmap_contours_andor[] = {
        {MKCOLOUR_0000               , MKCOLOUR_FFFF}, // MP_CLEAR
        {MKCOLOUR_0XX0(PC_GREY      ), MKCOLOUR_F00F}, // MP_RAILWAY
        {MKCOLOUR_0XX0(PC_BLACK     ), MKCOLOUR_F00F}, // MP_ROAD
        {MKCOLOUR_0XX0(PC_DARK_RED  ), MKCOLOUR_F00F}, // MP_HOUSE
        {MKCOLOUR_0000               , MKCOLOUR_FFFF}, // MP_TREES
        {MKCOLOUR_XXXX(PC_LIGHT_BLUE), MKCOLOUR_0000}, // MP_STATION
        {MKCOLOUR_XXXX(PC_WATER     ), MKCOLOUR_0000}, // MP_WATER
        {MKCOLOUR_0000               , MKCOLOUR_FFFF}, // MP_VOID
        {MKCOLOUR_XXXX(PC_DARK_RED  ), MKCOLOUR_0000}, // MP_INDUSTRY
        {MKCOLOUR_0000               , MKCOLOUR_FFFF}, // MP_TUNNELBRIDGE
        {MKCOLOUR_0XX0(PC_DARK_RED  ), MKCOLOUR_F00F}, // MP_OBJECT
        {MKCOLOUR_0XX0(PC_GREY      ), MKCOLOUR_F00F},
};

/** Colour masks for "Vehicles", "Industry", and "Vegetation" modes. */
static const AndOr _smallmap_vehicles_andor[] = {
        {MKCOLOUR_0000               , MKCOLOUR_FFFF}, // MP_CLEAR
        {MKCOLOUR_0XX0(PC_BLACK     ), MKCOLOUR_F00F}, // MP_RAILWAY
        {MKCOLOUR_0XX0(PC_BLACK     ), MKCOLOUR_F00F}, // MP_ROAD
        {MKCOLOUR_0XX0(PC_DARK_RED  ), MKCOLOUR_F00F}, // MP_HOUSE
        {MKCOLOUR_0000               , MKCOLOUR_FFFF}, // MP_TREES
        {MKCOLOUR_0XX0(PC_BLACK     ), MKCOLOUR_F00F}, // MP_STATION
        {MKCOLOUR_XXXX(PC_WATER     ), MKCOLOUR_0000}, // MP_WATER
        {MKCOLOUR_0000               , MKCOLOUR_FFFF}, // MP_VOID
        {MKCOLOUR_XXXX(PC_DARK_RED  ), MKCOLOUR_0000}, // MP_INDUSTRY
        {MKCOLOUR_0000               , MKCOLOUR_FFFF}, // MP_TUNNELBRIDGE
        {MKCOLOUR_0XX0(PC_DARK_RED  ), MKCOLOUR_F00F}, // MP_OBJECT
        {MKCOLOUR_0XX0(PC_BLACK     ), MKCOLOUR_F00F},
};

/** Mapping of tile type to importance of the tile (higher number means more interesting to show). */
static const uint8_t _tiletype_importance[] = {
        2, // MP_CLEAR
        8, // MP_RAILWAY
        7, // MP_ROAD
        5, // MP_HOUSE
        2, // MP_TREES
        9, // MP_STATION
        2, // MP_WATER
        1, // MP_VOID
        6, // MP_INDUSTRY
        8, // MP_TUNNELBRIDGE
        2, // MP_OBJECT
        0,
};


/**
 * Return the colour a tile would be displayed with in the small map in mode "Contour".
 * @param tile The tile of which we would like to get the colour.
 * @param t    Effective tile type of the tile (see #SmallMapWindow::GetTileColours).
 * @return The colour of tile in the small map in mode "Contour"
 */
static inline uint32_t GetSmallMapContoursPixels(TileIndex tile, TileType t)
{
        const SmallMapColourScheme *cs = &_heightmap_schemes[_settings_client.gui.smallmap_land_colour];
        return ApplyMask(cs->height_colours[TileHeight(tile)], &_smallmap_contours_andor[t]);
}

/**
 * Return the colour a tile would be displayed with in the small map in mode "Vehicles".
 *
 * @param tile The tile of which we would like to get the colour.
 * @param t    Effective tile type of the tile (see #SmallMapWindow::GetTileColours).
 * @return The colour of tile in the small map in mode "Vehicles"
 */
static inline uint32_t GetSmallMapVehiclesPixels(TileIndex, TileType t)
{
        const SmallMapColourScheme *cs = &_heightmap_schemes[_settings_client.gui.smallmap_land_colour];
        return ApplyMask(cs->default_colour, &_smallmap_vehicles_andor[t]);
}

/**
 * Return the colour a tile would be displayed with in the small map in mode "Industries".
 *
 * @param tile The tile of which we would like to get the colour.
 * @param t    Effective tile type of the tile (see #SmallMapWindow::GetTileColours).
 * @return The colour of tile in the small map in mode "Industries"
 */
static inline uint32_t GetSmallMapIndustriesPixels(TileIndex tile, TileType t)
{
        const SmallMapColourScheme *cs = &_heightmap_schemes[_settings_client.gui.smallmap_land_colour];
        return ApplyMask(_smallmap_show_heightmap ? cs->height_colours[TileHeight(tile)] : cs->default_colour, &_smallmap_vehicles_andor[t]);
}

/**
 * Return the colour a tile would be displayed with in the small map in mode "Routes".
 *
 * @param tile The tile of which we would like to get the colour.
 * @param t    Effective tile type of the tile (see #SmallMapWindow::GetTileColours).
 * @return The colour of tile  in the small map in mode "Routes"
 */
static inline uint32_t GetSmallMapRoutesPixels(TileIndex tile, TileType t)
{
        switch (t) {
                case MP_STATION:
                        switch (GetStationType(tile)) {
                                case STATION_RAIL:    return MKCOLOUR_XXXX(PC_VERY_DARK_BROWN);
                                case STATION_AIRPORT: return MKCOLOUR_XXXX(PC_RED);
                                case STATION_TRUCK:   return MKCOLOUR_XXXX(PC_ORANGE);
                                case STATION_BUS:     return MKCOLOUR_XXXX(PC_YELLOW);
                                case STATION_DOCK:    return MKCOLOUR_XXXX(PC_LIGHT_BLUE);
                                default:              return MKCOLOUR_FFFF;
                        }

                case MP_RAILWAY: {
                        AndOr andor = {
                                MKCOLOUR_0XX0(GetRailTypeInfo(GetRailType(tile))->map_colour),
                                _smallmap_contours_andor[t].mand
                        };

                        const SmallMapColourScheme *cs = &_heightmap_schemes[_settings_client.gui.smallmap_land_colour];
                        return ApplyMask(cs->default_colour, &andor);
                }

                case MP_ROAD: {
                        const RoadTypeInfo *rti = nullptr;
                        if (GetRoadTypeRoad(tile) != INVALID_ROADTYPE) {
                                rti = GetRoadTypeInfo(GetRoadTypeRoad(tile));
                        } else {
                                rti = GetRoadTypeInfo(GetRoadTypeTram(tile));
                        }
                        if (rti != nullptr) {
                                AndOr andor = {
                                        MKCOLOUR_0XX0(rti->map_colour),
                                        _smallmap_contours_andor[t].mand
                                };

                                const SmallMapColourScheme *cs = &_heightmap_schemes[_settings_client.gui.smallmap_land_colour];
                                return ApplyMask(cs->default_colour, &andor);
                        }
                        [[fallthrough]];
                }

                default:
                        /* Ground colour */
                        const SmallMapColourScheme *cs = &_heightmap_schemes[_settings_client.gui.smallmap_land_colour];
                        return ApplyMask(cs->default_colour, &_smallmap_contours_andor[t]);
        }
}

/**
 * Return the colour a tile would be displayed with in the small map in mode "link stats".
 *
 * @param tile The tile of which we would like to get the colour.
 * @param t    Effective tile type of the tile (see #SmallMapWindow::GetTileColours).
 * @return The colour of tile in the small map in mode "link stats"
 */
static inline uint32_t GetSmallMapLinkStatsPixels(TileIndex tile, TileType t)
{
        return _smallmap_show_heightmap ? GetSmallMapContoursPixels(tile, t) : GetSmallMapRoutesPixels(tile, t);
}

static const uint32_t _vegetation_clear_bits[] = {
        MKCOLOUR_XXXX(PC_GRASS_LAND), ///< full grass
        MKCOLOUR_XXXX(PC_ROUGH_LAND), ///< rough land
        MKCOLOUR_XXXX(PC_GREY),       ///< rocks
        MKCOLOUR_XXXX(PC_FIELDS),     ///< fields
        MKCOLOUR_XXXX(PC_LIGHT_BLUE), ///< snow
        MKCOLOUR_XXXX(PC_ORANGE),     ///< desert
        MKCOLOUR_XXXX(PC_GRASS_LAND), ///< unused
        MKCOLOUR_XXXX(PC_GRASS_LAND), ///< unused
};

/**
 * Return the colour a tile would be displayed with in the smallmap in mode "Vegetation".
 *
 * @param tile The tile of which we would like to get the colour.
 * @param t    Effective tile type of the tile (see #SmallMapWindow::GetTileColours).
 * @return The colour of tile  in the smallmap in mode "Vegetation"
 */
static inline uint32_t GetSmallMapVegetationPixels(TileIndex tile, TileType t)
{
        switch (t) {
                case MP_CLEAR:
                        if (IsClearGround(tile, CLEAR_GRASS)) {
                                if (GetClearDensity(tile) < 3) return MKCOLOUR_XXXX(PC_BARE_LAND);
                                if (GetTropicZone(tile) == TROPICZONE_RAINFOREST) return MKCOLOUR_XXXX(PC_RAINFOREST);
                        }
                        return _vegetation_clear_bits[GetClearGround(tile)];

                case MP_INDUSTRY:
                        return IsTileForestIndustry(tile) ? MKCOLOUR_XXXX(PC_GREEN) : MKCOLOUR_XXXX(PC_DARK_RED);

                case MP_TREES:
                        if (GetTreeGround(tile) == TREE_GROUND_SNOW_DESERT || GetTreeGround(tile) == TREE_GROUND_ROUGH_SNOW) {
                                return (_settings_game.game_creation.landscape == LT_ARCTIC) ? MKCOLOUR_XYYX(PC_LIGHT_BLUE, PC_TREES) : MKCOLOUR_XYYX(PC_ORANGE, PC_TREES);
                        }
                        return (GetTropicZone(tile) == TROPICZONE_RAINFOREST) ? MKCOLOUR_XYYX(PC_RAINFOREST, PC_TREES) : MKCOLOUR_XYYX(PC_GRASS_LAND, PC_TREES);

                default:
                        return ApplyMask(MKCOLOUR_XXXX(PC_GRASS_LAND), &_smallmap_vehicles_andor[t]);
        }
}

/**
 * Return the colour a tile would be displayed with in the small map in mode "Owner".
 *
 * @note If include_heightmap is IH_NEVER, the return value can safely be used as a palette colour (by masking it to a uint8_t)
 * @param tile              The tile of which we would like to get the colour.
 * @param t                 Effective tile type of the tile (see #SmallMapWindow::GetTileColours).
 * @param include_heightmap Whether to return the heightmap/contour colour of this tile (instead of the default land tile colour)
 * @return The colour of tile in the small map in mode "Owner"
 */
uint32_t GetSmallMapOwnerPixels(TileIndex tile, TileType t, IncludeHeightmap include_heightmap)
{
        Owner o;

        switch (t) {
                case MP_VOID:     return MKCOLOUR_XXXX(PC_BLACK);
                case MP_INDUSTRY: return MKCOLOUR_XXXX(PC_DARK_GREY);
                case MP_HOUSE:    return MKCOLOUR_XXXX(PC_DARK_RED);
                default:          o = GetTileOwner(tile); break;
                /* FIXME: For MP_ROAD there are multiple owners.
                 * GetTileOwner returns the rail owner (level crossing) resp. the owner of ROADTYPE_ROAD (normal road),
                 * even if there are no ROADTYPE_ROAD bits on the tile.
                 */
        }

        if ((o < MAX_COMPANIES && !_legend_land_owners[_company_to_list_pos[o]].show_on_map) || o == OWNER_NONE || o == OWNER_WATER) {
                if (t == MP_WATER) return MKCOLOUR_XXXX(PC_WATER);
                const SmallMapColourScheme *cs = &_heightmap_schemes[_settings_client.gui.smallmap_land_colour];
                return ((include_heightmap == IncludeHeightmap::IfEnabled && _smallmap_show_heightmap) || include_heightmap == IncludeHeightmap::Always)
                        ? cs->height_colours[TileHeight(tile)] : cs->default_colour;
        } else if (o == OWNER_TOWN) {
                return MKCOLOUR_XXXX(PC_DARK_RED);
        }

        return MKCOLOUR_XXXX(_legend_land_owners[_company_to_list_pos[o]].colour);
}

/** Vehicle colours in #SMT_VEHICLES mode. Indexed by #VehicleType. */
static const uint8_t _vehicle_type_colours[6] = {
        PC_RED, PC_YELLOW, PC_LIGHT_BLUE, PC_WHITE, PC_BLACK, PC_RED
};

/** Types of legends in the #WID_SM_LEGEND widget. */
enum SmallMapType : uint8_t {
        SMT_CONTOUR,
        SMT_VEHICLES,
        SMT_INDUSTRY,
        SMT_LINKSTATS,
        SMT_ROUTES,
        SMT_VEGETATION,
        SMT_OWNER,
};
DECLARE_ENUM_AS_ADDABLE(SmallMapType)

/** Class managing the smallmap window. */
class SmallMapWindow : public Window {
protected:
        /** Available kinds of zoomlevel changes. */
        enum ZoomLevelChange {
                ZLC_INITIALIZE, ///< Initialize zoom level.
                ZLC_ZOOM_OUT,   ///< Zoom out.
                ZLC_ZOOM_IN,    ///< Zoom in.
        };

        static SmallMapType map_type; ///< Currently displayed legends.
        static bool show_towns;       ///< Display town names in the smallmap.
        static bool show_ind_names;   ///< Display industry names in the smallmap.
        static int map_height_limit;  ///< Currently used/cached map height limit.

        static const uint INDUSTRY_MIN_NUMBER_OF_COLUMNS = 2; ///< Minimal number of columns in the #WID_SM_LEGEND widget for the #SMT_INDUSTRY legend.

        uint min_number_of_columns;    ///< Minimal number of columns in legends.
        uint min_number_of_fixed_rows; ///< Minimal number of rows in the legends for the fixed layouts only (all except #SMT_INDUSTRY).
        uint column_width;             ///< Width of a column in the #WID_SM_LEGEND widget.
        uint legend_width;             ///< Width of legend 'blob'.

        int32_t scroll_x;  ///< Horizontal world coordinate of the base tile left of the top-left corner of the smallmap display.
        int32_t scroll_y;  ///< Vertical world coordinate of the base tile left of the top-left corner of the smallmap display.
        int32_t subscroll; ///< Number of pixels (0..3) between the right end of the base tile and the pixel at the top-left corner of the smallmap display.
        int zoom;        ///< Zoom level. Bigger number means more zoom-out (further away).

        std::unique_ptr<LinkGraphOverlay> overlay;

        /** Notify the industry chain window to stop sending newly selected industries. */
        static void BreakIndustryChainLink()
        {
                InvalidateWindowClassesData(WC_INDUSTRY_CARGOES, NUM_INDUSTRYTYPES);
        }

        static inline Point SmallmapRemapCoords(int x, int y)
        {
                Point pt;
                pt.x = (y - x) * 2;
                pt.y = y + x;
                return pt;
        }

        /**
         * Draws vertical part of map indicator
         * @param x X coord of left/right border of main viewport
         * @param y Y coord of top border of main viewport
         * @param y2 Y coord of bottom border of main viewport
         */
        static inline void DrawVertMapIndicator(int x, int y, int y2)
        {
                GfxFillRect(x, y,      x, y + 3, PC_VERY_LIGHT_YELLOW);
                GfxFillRect(x, y2 - 3, x, y2,    PC_VERY_LIGHT_YELLOW);
        }

        /**
         * Draws horizontal part of map indicator
         * @param x X coord of left border of main viewport
         * @param x2 X coord of right border of main viewport
         * @param y Y coord of top/bottom border of main viewport
         */
        static inline void DrawHorizMapIndicator(int x, int x2, int y)
        {
                GfxFillRect(x,      y, x + 3, y, PC_VERY_LIGHT_YELLOW);
                GfxFillRect(x2 - 3, y, x2,    y, PC_VERY_LIGHT_YELLOW);
        }

        /**
         * Compute minimal required width of the legends.
         * @return Minimally needed width for displaying the smallmap legends in pixels.
         */
        inline uint GetMinLegendWidth() const
        {
                return WidgetDimensions::scaled.framerect.left + this->min_number_of_columns * this->column_width;
        }

        /**
         * Return number of columns that can be displayed in \a width pixels.
         * @return Number of columns to display.
         */
        inline uint GetNumberColumnsLegend(uint width) const
        {
                return width / this->column_width;
        }

        /**
         * Compute height given a number of columns.
         * @param num_columns Number of columns.
         * @return Needed height for displaying the smallmap legends in pixels.
         */
        inline uint GetLegendHeight(uint num_columns) const
        {
                return WidgetDimensions::scaled.framerect.Vertical() +
                                this->GetNumberRowsLegend(num_columns) * GetCharacterHeight(FS_SMALL);
        }

        /**
         * Get a bitmask for company links to be displayed. Usually this will be
         * the _local_company. Spectators get to see all companies' links.
         * @return Company mask.
         */
        inline CompanyMask GetOverlayCompanyMask() const
        {
                return Company::IsValidID(_local_company) ? 1U << _local_company : MAX_UVALUE(CompanyMask);
        }

        /** Blink the industries (if selected) on a regular interval. */
        IntervalTimer<TimerWindow> blink_interval = {std::chrono::milliseconds(450), [this](auto) {
                Blink();
        }};

        /** Update the whole map on a regular interval. */
        IntervalTimer<TimerWindow> refresh_interval = {std::chrono::milliseconds(930), [this](auto) {
                ForceRefresh();
        }};

        /**
         * Rebuilds the colour indices used for fast access to the smallmap contour colours based on the heightlevel.
         */
        void RebuildColourIndexIfNecessary()
        {
                /* Rebuild colour indices if necessary. */
                if (SmallMapWindow::map_height_limit == _settings_game.construction.map_height_limit) return;

                for (auto &heightmap_scheme : _heightmap_schemes) {
                        /* The heights go from 0 up to and including maximum. */
                        size_t heights = _settings_game.construction.map_height_limit + 1;
                        heightmap_scheme.height_colours.resize(heights);

                        for (size_t z = 0; z < heights; z++) {
                                size_t access_index = (heightmap_scheme.height_colours_base.size() * z) / heights;

                                /* Choose colour by mapping the range (0..max heightlevel) on the complete colour table. */
                                heightmap_scheme.height_colours[z] = heightmap_scheme.height_colours_base[access_index];
                        }
                }

                SmallMapWindow::map_height_limit = _settings_game.construction.map_height_limit;
                BuildLandLegend();
        }

        /**
         * Get the number of rows in the legend from the number of columns. Those
         * are at least min_number_of_fixed_rows and possibly more if there are so
         * many cargoes, industry types or companies that they won't fit in the
         * available space.
         * @param columns Number of columns in the legend.
         * @return Number of rows needed for everything to fit in.
         */
        uint GetNumberRowsLegend(uint columns) const
        {
                /* Reserve one column for link colours */
                uint num_rows_linkstats = CeilDiv(_smallmap_cargo_count, columns - 1);
                uint num_rows_others = CeilDiv(std::max(_smallmap_industry_count, _smallmap_company_count), columns);
                return std::max({this->min_number_of_fixed_rows, num_rows_linkstats, num_rows_others});
        }

        /**
         * Select and toggle a legend item. When CTRL is pressed, disable all other
         * items in the group defined by begin_legend_item and end_legend_item and
         * keep the clicked one enabled even if it was already enabled before. If
         * the other items in the group are all disabled already and CTRL is pressed
         * enable them instead.
         * @param click_pos the index of the item being selected
         * @param legend the legend from which we select
         * @param end_legend_item index one past the last item in the group to be inverted
         * @param begin_legend_item index of the first item in the group to be inverted
         */
        void SelectLegendItem(int click_pos, LegendAndColour *legend, int end_legend_item, int begin_legend_item = 0)
        {
                if (_ctrl_pressed) {
                        /* Disable all, except the clicked one */
                        bool changes = false;
                        for (int i = begin_legend_item; i != end_legend_item; i++) {
                                bool new_state = (i == click_pos);
                                if (legend[i].show_on_map != new_state) {
                                        changes = true;
                                        legend[i].show_on_map = new_state;
                                }
                        }
                        if (!changes) {
                                /* Nothing changed? Then show all (again). */
                                for (int i = begin_legend_item; i != end_legend_item; i++) {
                                        legend[i].show_on_map = true;
                                }
                        }
                } else {
                        legend[click_pos].show_on_map = !legend[click_pos].show_on_map;
                }

                if (this->map_type == SMT_INDUSTRY) this->BreakIndustryChainLink();
        }

        /**
         * Select a new map type.
         * @param map_type New map type.
         */
        void SwitchMapType(SmallMapType map_type)
        {
                this->RaiseWidget(WID_SM_CONTOUR + this->map_type);
                this->map_type = map_type;
                this->LowerWidget(WID_SM_CONTOUR + this->map_type);

                this->SetupWidgetData();

                if (map_type == SMT_LINKSTATS) this->overlay->SetDirty();
                if (map_type != SMT_INDUSTRY) this->BreakIndustryChainLink();
                this->ReInit();
        }

        /**
         * Set new #scroll_x, #scroll_y, and #subscroll values after limiting them such that the center
         * of the smallmap always contains a part of the map.
         * @param sx  Proposed new #scroll_x
         * @param sy  Proposed new #scroll_y
         * @param sub Proposed new #subscroll
         */
        void SetNewScroll(int sx, int sy, int sub)
        {
                const NWidgetBase *wi = this->GetWidget<NWidgetBase>(WID_SM_MAP);
                Point hv = InverseRemapCoords(wi->current_x * ZOOM_BASE * TILE_SIZE / 2, wi->current_y * ZOOM_BASE * TILE_SIZE / 2);
                hv.x *= this->zoom;
                hv.y *= this->zoom;

                if (sx < -hv.x) {
                        sx = -hv.x;
                        sub = 0;
                }
                if (sx > (int)(Map::MaxX() * TILE_SIZE) - hv.x) {
                        sx = Map::MaxX() * TILE_SIZE - hv.x;
                        sub = 0;
                }
                if (sy < -hv.y) {
                        sy = -hv.y;
                        sub = 0;
                }
                if (sy > (int)(Map::MaxY() * TILE_SIZE) - hv.y) {
                        sy = Map::MaxY() * TILE_SIZE - hv.y;
                        sub = 0;
                }

                this->scroll_x = sx;
                this->scroll_y = sy;
                this->subscroll = sub;
                if (this->map_type == SMT_LINKSTATS) this->overlay->SetDirty();
        }

        /**
         * Adds map indicators to the smallmap.
         */
        void DrawMapIndicators() const
        {
                /* Find main viewport. */
                const Viewport *vp = GetMainWindow()->viewport;

                Point upper_left_smallmap_coord  = InverseRemapCoords2(vp->virtual_left, vp->virtual_top);
                Point lower_right_smallmap_coord = InverseRemapCoords2(vp->virtual_left + vp->virtual_width - 1, vp->virtual_top + vp->virtual_height - 1);

                Point upper_left = this->RemapTile(upper_left_smallmap_coord.x / (int)TILE_SIZE, upper_left_smallmap_coord.y / (int)TILE_SIZE);
                upper_left.x -= this->subscroll;

                Point lower_right = this->RemapTile(lower_right_smallmap_coord.x / (int)TILE_SIZE, lower_right_smallmap_coord.y / (int)TILE_SIZE);
                lower_right.x -= this->subscroll;

                SmallMapWindow::DrawVertMapIndicator(upper_left.x, upper_left.y, lower_right.y);
                SmallMapWindow::DrawVertMapIndicator(lower_right.x, upper_left.y, lower_right.y);

                SmallMapWindow::DrawHorizMapIndicator(upper_left.x, lower_right.x, upper_left.y);
                SmallMapWindow::DrawHorizMapIndicator(upper_left.x, lower_right.x, lower_right.y);
        }

        /**
         * Draws one column of tiles of the small map in a certain mode onto the screen buffer, skipping the shifted rows in between.
         *
         * @param dst Pointer to a part of the screen buffer to write to.
         * @param xc The X coordinate of the first tile in the column.
         * @param yc The Y coordinate of the first tile in the column
         * @param pitch Number of pixels to advance in the screen buffer each time a pixel is written.
         * @param reps Number of lines to draw
         * @param start_pos Position of first pixel to draw.
         * @param end_pos Position of last pixel to draw (exclusive).
         * @param blitter current blitter
         * @note If pixel position is below \c 0, skip drawing.
         */
        void DrawSmallMapColumn(void *dst, uint xc, uint yc, int pitch, int reps, int start_pos, int end_pos, Blitter *blitter) const
        {
                void *dst_ptr_abs_end = blitter->MoveTo(_screen.dst_ptr, 0, _screen.height);
                uint min_xy = _settings_game.construction.freeform_edges ? 1 : 0;

                do {
                        /* Check if the tile (xc,yc) is within the map range */
                        if (xc >= Map::MaxX() || yc >= Map::MaxY()) continue;

                        /* Check if the dst pointer points to a pixel inside the screen buffer */
                        if (dst < _screen.dst_ptr) continue;
                        if (dst >= dst_ptr_abs_end) continue;

                        /* Construct tilearea covered by (xc, yc, xc + this->zoom, yc + this->zoom) such that it is within min_xy limits. */
                        TileArea ta;
                        if (min_xy == 1 && (xc == 0 || yc == 0)) {
                                if (this->zoom == 1) continue; // The tile area is empty, don't draw anything.

                                ta = TileArea(TileXY(std::max(min_xy, xc), std::max(min_xy, yc)), this->zoom - (xc == 0), this->zoom - (yc == 0));
                        } else {
                                ta = TileArea(TileXY(xc, yc), this->zoom, this->zoom);
                        }
                        ta.ClampToMap(); // Clamp to map boundaries (may contain MP_VOID tiles!).

                        uint32_t val = this->GetTileColours(ta);
                        uint8_t *val8 = (uint8_t *)&val;
                        int idx = std::max(0, -start_pos);
                        for (int pos = std::max(0, start_pos); pos < end_pos; pos++) {
                                blitter->SetPixel(dst, idx, 0, val8[idx]);
                                idx++;
                        }
                /* Switch to next tile in the column */
                } while (xc += this->zoom, yc += this->zoom, dst = blitter->MoveTo(dst, pitch, 0), --reps != 0);
        }

        /**
         * Adds vehicles to the smallmap.
         * @param dpi the part of the smallmap to be drawn into
         * @param blitter current blitter
         */
        void DrawVehicles(const DrawPixelInfo *dpi, Blitter *blitter) const
        {
                for (const Vehicle *v : Vehicle::Iterate()) {
                        if (v->type == VEH_EFFECT) continue;
                        if (v->vehstatus & (VS_HIDDEN | VS_UNCLICKABLE)) continue;

                        /* Remap into flat coordinates. */
                        Point pt = this->RemapTile(v->x_pos / (int)TILE_SIZE, v->y_pos / (int)TILE_SIZE);

                        int y = pt.y - dpi->top;
                        if (!IsInsideMM(y, 0, dpi->height)) continue; // y is out of bounds.

                        bool skip = false; // Default is to draw both pixels.
                        int x = pt.x - this->subscroll - 3 - dpi->left; // Offset X coordinate.
                        if (x < 0) {
                                /* if x+1 is 0, that means we're on the very left edge,
                                 * and should thus only draw a single pixel */
                                if (++x != 0) continue;
                                skip = true;
                        } else if (x >= dpi->width - 1) {
                                /* Check if we're at the very right edge, and if so draw only a single pixel */
                                if (x != dpi->width - 1) continue;
                                skip = true;
                        }

                        /* Calculate pointer to pixel and the colour */
                        uint8_t colour = (this->map_type == SMT_VEHICLES) ? _vehicle_type_colours[v->type] : PC_WHITE;

                        /* And draw either one or two pixels depending on clipping */
                        blitter->SetPixel(dpi->dst_ptr, x, y, colour);
                        if (!skip) blitter->SetPixel(dpi->dst_ptr, x + 1, y, colour);
                }
        }

        /**
         * Adds town names to the smallmap.
         * @param dpi the part of the smallmap to be drawn into
         */
        void DrawTowns(const DrawPixelInfo *dpi, const int vertical_padding) const
        {
                for (const Town *t : Town::Iterate()) {
                        /* Remap the town coordinate */
                        Point pt = this->RemapTile(TileX(t->xy), TileY(t->xy));
                        int x = pt.x - this->subscroll - (t->cache.sign.width_small >> 1);
                        int y = pt.y + vertical_padding;

                        /* Check if the town sign is within bounds */
                        if (x + t->cache.sign.width_small > dpi->left &&
                                        x < dpi->left + dpi->width &&
                                        y + GetCharacterHeight(FS_SMALL) > dpi->top &&
                                        y < dpi->top + dpi->height) {
                                /* And draw it. */
                                SetDParam(0, t->index);
                                DrawString(x, x + t->cache.sign.width_small, y, STR_SMALLMAP_TOWN);
                        }
                }
        }

        /**
         * Adds industry names to the smallmap.
         * @param dpi the part of the smallmap to be drawn into
         */
        void DrawIndustryNames(const DrawPixelInfo *dpi, const int vertical_padding) const
        {
                if (this->map_type != SMT_INDUSTRY) return;

                for (const Industry *i : Industry::Iterate()) {
                        const LegendAndColour &tbl = _legend_from_industries[_industry_to_list_pos[i->type]];
                        if (!tbl.show_on_map) continue;

                        /* Industry names blink together with their blobs in the smallmap. */
                        const bool is_blinking = i->type == _smallmap_industry_highlight && !_smallmap_industry_highlight_state;
                        if (is_blinking) continue;

                        if (_industry_to_name_string_width[i->type] == 0) {
                                _industry_to_name_string_width[i->type] = GetStringBoundingBox(tbl.legend, FS_SMALL).width;
                        }
                        const uint16_t &legend_text_width = _industry_to_name_string_width[i->type];

                        /* Remap the industry coordinate */
                        const TileIndex &tile = i->location.GetCenterTile();
                        const Point pt = this->RemapTile(TileX(tile), TileY(tile));
                        const int x = pt.x - this->subscroll - (legend_text_width / 2);
                        const int y = pt.y + vertical_padding;

                        /* Check if the industry name is within bounds */
                        if (x + legend_text_width > dpi->left &&
                                        x < dpi->left + dpi->width &&
                                        y + GetCharacterHeight(FS_SMALL) > dpi->top &&
                                        y < dpi->top + dpi->height) {

                                /* And draw it. */
                                DrawString(x, x + legend_text_width, y, tbl.legend, TC_WHITE, SA_LEFT, false, FS_SMALL);
                        }
                }
        }

        /**
         * Draws the small map.
         *
         * Basically, the small map is draw column of pixels by column of pixels. The pixels
         * are drawn directly into the screen buffer. The final map is drawn in multiple passes.
         * The passes are:
         * <ol><li>The colours of tiles in the different modes.</li>
         * <li>Town names (optional)</li></ol>
         *
         * @param dpi pointer to pixel to write onto
         */
        void DrawSmallMap(DrawPixelInfo *dpi) const
        {
                Blitter *blitter = BlitterFactory::GetCurrentBlitter();
                AutoRestoreBackup dpi_backup(_cur_dpi, dpi);

                /* Clear it */
                GfxFillRect(dpi->left, dpi->top, dpi->left + dpi->width - 1, dpi->top + dpi->height - 1, PC_BLACK);

                /* Which tile is displayed at (dpi->left, dpi->top)? */
                int dx;
                Point tile = this->PixelToTile(dpi->left, dpi->top, &dx);
                int tile_x = this->scroll_x / (int)TILE_SIZE + tile.x;
                int tile_y = this->scroll_y / (int)TILE_SIZE + tile.y;

                void *ptr = blitter->MoveTo(dpi->dst_ptr, -dx - 4, 0);
                int x = - dx - 4;
                int y = 0;

                for (;;) {
                        /* Distance from left edge */
                        if (x >= -3) {
                                if (x >= dpi->width) break; // Exit the loop.

                                int end_pos = std::min(dpi->width, x + 4);
                                int reps = (dpi->height - y + 1) / 2; // Number of lines.
                                if (reps > 0) {
                                        this->DrawSmallMapColumn(ptr, tile_x, tile_y, dpi->pitch * 2, reps, x, end_pos, blitter);
                                }
                        }

                        if (y == 0) {
                                tile_y += this->zoom;
                                y++;
                                ptr = blitter->MoveTo(ptr, 0, 1);
                        } else {
                                tile_x -= this->zoom;
                                y--;
                                ptr = blitter->MoveTo(ptr, 0, -1);
                        }
                        ptr = blitter->MoveTo(ptr, 2, 0);
                        x += 2;
                }

                /* Draw vehicles */
                if (this->map_type == SMT_CONTOUR || this->map_type == SMT_VEHICLES) this->DrawVehicles(dpi, blitter);

                /* Draw link stat overlay */
                if (this->map_type == SMT_LINKSTATS) this->overlay->Draw(dpi);

                const int map_labels_vertical_padding = ScaleGUITrad(2);

                /* Draw town names */
                if (this->show_towns) this->DrawTowns(dpi, map_labels_vertical_padding);

                /* Draw industry names */
                if (this->show_ind_names) this->DrawIndustryNames(dpi, map_labels_vertical_padding);

                /* Draw map indicators */
                this->DrawMapIndicators();
        }

        /**
         * Remap tile to location on this smallmap.
         * @param tile_x X coordinate of the tile.
         * @param tile_y Y coordinate of the tile.
         * @return Position to draw on.
         */
        Point RemapTile(int tile_x, int tile_y) const
        {
                int x_offset = tile_x - this->scroll_x / (int)TILE_SIZE;
                int y_offset = tile_y - this->scroll_y / (int)TILE_SIZE;

                if (this->zoom == 1) return SmallmapRemapCoords(x_offset, y_offset);

                /* For negative offsets, round towards -inf. */
                if (x_offset < 0) x_offset -= this->zoom - 1;
                if (y_offset < 0) y_offset -= this->zoom - 1;

                return SmallmapRemapCoords(x_offset / this->zoom, y_offset / this->zoom);
        }

        /**
         * Determine the tile relative to the base tile of the smallmap, and the pixel position at
         * that tile for a point in the smallmap.
         * @param px       Horizontal coordinate of the pixel.
         * @param py       Vertical coordinate of the pixel.
         * @param[out] sub Pixel position at the tile (0..3).
         * @param add_sub  Add current #subscroll to the position.
         * @return Tile being displayed at the given position relative to #scroll_x and #scroll_y.
         * @note The #subscroll offset is already accounted for.
         */
        Point PixelToTile(int px, int py, int *sub, bool add_sub = true) const
        {
                if (add_sub) px += this->subscroll;  // Total horizontal offset.

                /* For each two rows down, add a x and a y tile, and
                 * For each four pixels to the right, move a tile to the right. */
                Point pt = {((py >> 1) - (px >> 2)) * this->zoom, ((py >> 1) + (px >> 2)) * this->zoom};
                px &= 3;

                if (py & 1) { // Odd number of rows, handle the 2 pixel shift.
                        if (px < 2) {
                                pt.x += this->zoom;
                                px += 2;
                        } else {
                                pt.y += this->zoom;
                                px -= 2;
                        }
                }

                *sub = px;
                return pt;
        }

        /**
         * Compute base parameters of the smallmap such that tile (\a tx, \a ty) starts at pixel (\a x, \a y).
         * @param tx       Tile x coordinate.
         * @param ty       Tile y coordinate.
         * @param x        Non-negative horizontal position in the display where the tile starts.
         * @param y        Non-negative vertical position in the display where the tile starts.
         * @param[out] sub Value of #subscroll needed.
         * @return #scroll_x, #scroll_y values.
         */
        Point ComputeScroll(int tx, int ty, int x, int y, int *sub) const
        {
                assert(x >= 0 && y >= 0);

                int new_sub;
                Point tile_xy = PixelToTile(x, y, &new_sub, false);
                tx -= tile_xy.x;
                ty -= tile_xy.y;

                Point scroll;
                if (new_sub == 0) {
                        *sub = 0;
                        scroll.x = (tx + this->zoom) * TILE_SIZE;
                        scroll.y = (ty - this->zoom) * TILE_SIZE;
                } else {
                        *sub = 4 - new_sub;
                        scroll.x = (tx + 2 * this->zoom) * TILE_SIZE;
                        scroll.y = (ty - 2 * this->zoom) * TILE_SIZE;
                }
                return scroll;
        }

        /**
         * Initialize or change the zoom level.
         * @param change  Way to change the zoom level.
         * @param zoom_pt Position to keep fixed while zooming.
         * @pre \c *zoom_pt should contain a point in the smallmap display when zooming in or out.
         */
        void SetZoomLevel(ZoomLevelChange change, const Point *zoom_pt)
        {
                static const int zoomlevels[] = {1, 2, 4, 6, 8}; // Available zoom levels. Bigger number means more zoom-out (further away).
                static const int MIN_ZOOM_INDEX = 0;
                static const int MAX_ZOOM_INDEX = lengthof(zoomlevels) - 1;

                int new_index, cur_index, sub;
                Point tile;
                switch (change) {
                        case ZLC_INITIALIZE:
                                cur_index = - 1; // Definitely different from new_index.
                                new_index = MIN_ZOOM_INDEX;
                                tile.x = tile.y = 0;
                                break;

                        case ZLC_ZOOM_IN:
                        case ZLC_ZOOM_OUT:
                                for (cur_index = MIN_ZOOM_INDEX; cur_index <= MAX_ZOOM_INDEX; cur_index++) {
                                        if (this->zoom == zoomlevels[cur_index]) break;
                                }
                                assert(cur_index <= MAX_ZOOM_INDEX);

                                tile = this->PixelToTile(zoom_pt->x, zoom_pt->y, &sub);
                                new_index = Clamp(cur_index + ((change == ZLC_ZOOM_IN) ? -1 : 1), MIN_ZOOM_INDEX, MAX_ZOOM_INDEX);
                                break;

                        default: NOT_REACHED();
                }

                if (new_index != cur_index) {
                        this->zoom = zoomlevels[new_index];
                        if (cur_index >= 0) {
                                Point new_tile = this->PixelToTile(zoom_pt->x, zoom_pt->y, &sub);
                                this->SetNewScroll(this->scroll_x + (tile.x - new_tile.x) * TILE_SIZE,
                                                this->scroll_y + (tile.y - new_tile.y) * TILE_SIZE, sub);
                        } else if (this->map_type == SMT_LINKSTATS) {
                                this->overlay->SetDirty();
                        }
                        this->SetWidgetDisabledState(WID_SM_ZOOM_IN,  this->zoom == zoomlevels[MIN_ZOOM_INDEX]);
                        this->SetWidgetDisabledState(WID_SM_ZOOM_OUT, this->zoom == zoomlevels[MAX_ZOOM_INDEX]);
                        this->SetDirty();
                }
        }

        /**
         * Set the link graph overlay cargo mask from the legend.
         */
        void SetOverlayCargoMask()
        {
                CargoTypes cargo_mask = 0;
                for (int i = 0; i != _smallmap_cargo_count; ++i) {
                        if (_legend_linkstats[i].show_on_map) SetBit(cargo_mask, _legend_linkstats[i].type);
                }
                this->overlay->SetCargoMask(cargo_mask);
        }

        /**
         * Function to set up widgets depending on the information being shown on the smallmap.
         */
        void SetupWidgetData()
        {
                StringID legend_tooltip;
                StringID enable_all_tooltip;
                StringID disable_all_tooltip;
                int industry_names_select_plane;
                int select_buttons_plane;
                switch (this->map_type) {
                        case SMT_INDUSTRY:
                                legend_tooltip = STR_SMALLMAP_TOOLTIP_INDUSTRY_SELECTION;
                                enable_all_tooltip = STR_SMALLMAP_TOOLTIP_ENABLE_ALL_INDUSTRIES;
                                disable_all_tooltip = STR_SMALLMAP_TOOLTIP_DISABLE_ALL_INDUSTRIES;
                                industry_names_select_plane = 0;
                                select_buttons_plane = 0;
                                break;

                        case SMT_OWNER:
                                legend_tooltip = STR_SMALLMAP_TOOLTIP_COMPANY_SELECTION;
                                enable_all_tooltip = STR_SMALLMAP_TOOLTIP_ENABLE_ALL_COMPANIES;
                                disable_all_tooltip = STR_SMALLMAP_TOOLTIP_DISABLE_ALL_COMPANIES;
                                industry_names_select_plane = SZSP_NONE;
                                select_buttons_plane = 0;
                                break;

                        case SMT_LINKSTATS:
                                legend_tooltip = STR_SMALLMAP_TOOLTIP_CARGO_SELECTION;
                                enable_all_tooltip = STR_SMALLMAP_TOOLTIP_ENABLE_ALL_CARGOS;
                                disable_all_tooltip = STR_SMALLMAP_TOOLTIP_DISABLE_ALL_CARGOS;
                                industry_names_select_plane = SZSP_NONE;
                                select_buttons_plane = 0;
                                break;

                        default:
                                legend_tooltip = STR_NULL;
                                enable_all_tooltip = STR_NULL;
                                disable_all_tooltip = STR_NULL;
                                industry_names_select_plane = SZSP_NONE;
                                select_buttons_plane = 1;
                                break;
                }

                this->GetWidget<NWidgetCore>(WID_SM_LEGEND)->SetDataTip(STR_NULL, legend_tooltip);
                this->GetWidget<NWidgetCore>(WID_SM_ENABLE_ALL)->SetDataTip(STR_SMALLMAP_ENABLE_ALL, enable_all_tooltip);
                this->GetWidget<NWidgetCore>(WID_SM_DISABLE_ALL)->SetDataTip(STR_SMALLMAP_DISABLE_ALL, disable_all_tooltip);
                this->GetWidget<NWidgetStacked>(WID_SM_SHOW_IND_NAMES_SEL)->SetDisplayedPlane(industry_names_select_plane);
                this->GetWidget<NWidgetStacked>(WID_SM_SELECT_BUTTONS)->SetDisplayedPlane(select_buttons_plane);
        }

        /**
         * Decide which colours to show to the user for a group of tiles.
         * @param ta Tile area to investigate.
         * @return Colours to display.
         */
        uint32_t GetTileColours(const TileArea &ta) const
        {
                int importance = 0;
                TileIndex tile = INVALID_TILE; // Position of the most important tile.
                TileType et = MP_VOID;         // Effective tile type at that position.

                for (TileIndex ti : ta) {
                        TileType ttype = GetTileType(ti);

                        switch (ttype) {
                                case MP_TUNNELBRIDGE: {
                                        TransportType tt = GetTunnelBridgeTransportType(ti);

                                        switch (tt) {
                                                case TRANSPORT_RAIL: ttype = MP_RAILWAY; break;
                                                case TRANSPORT_ROAD: ttype = MP_ROAD;    break;
                                                default:             ttype = MP_WATER;   break;
                                        }
                                        break;
                                }

                                case MP_INDUSTRY:
                                        /* Special handling of industries while in "Industries" smallmap view. */
                                        if (this->map_type == SMT_INDUSTRY) {
                                                /* If industry is allowed to be seen, use its colour on the map.
                                                 * This has the highest priority above any value in _tiletype_importance. */
                                                IndustryType type = Industry::GetByTile(ti)->type;
                                                if (_legend_from_industries[_industry_to_list_pos[type]].show_on_map) {
                                                        if (type == _smallmap_industry_highlight) {
                                                                if (_smallmap_industry_highlight_state) return MKCOLOUR_XXXX(PC_WHITE);
                                                        } else {
                                                                return GetIndustrySpec(type)->map_colour * 0x01010101;
                                                        }
                                                }
                                                /* Otherwise make it disappear */
                                                ttype = IsTileOnWater(ti) ? MP_WATER : MP_CLEAR;
                                        }
                                        break;

                                default:
                                        break;
                        }

                        if (_tiletype_importance[ttype] > importance) {
                                importance = _tiletype_importance[ttype];
                                tile = ti;
                                et = ttype;
                        }
                }

                switch (this->map_type) {
                        case SMT_CONTOUR:
                                return GetSmallMapContoursPixels(tile, et);

                        case SMT_VEHICLES:
                                return GetSmallMapVehiclesPixels(tile, et);

                        case SMT_INDUSTRY:
                                return GetSmallMapIndustriesPixels(tile, et);

                        case SMT_LINKSTATS:
                                return GetSmallMapLinkStatsPixels(tile, et);

                        case SMT_ROUTES:
                                return GetSmallMapRoutesPixels(tile, et);

                        case SMT_VEGETATION:
                                return GetSmallMapVegetationPixels(tile, et);

                        case SMT_OWNER:
                                return GetSmallMapOwnerPixels(tile, et, IncludeHeightmap::IfEnabled);

                        default: NOT_REACHED();
                }
        }

        /**
         * Determines the mouse position on the legend.
         * @param pt Mouse position.
         * @return Legend item under the mouse.
         */
        int GetPositionOnLegend(Point pt)
        {
                const NWidgetBase *wi = this->GetWidget<NWidgetBase>(WID_SM_LEGEND);
                uint line = (pt.y - wi->pos_y - WidgetDimensions::scaled.framerect.top) / GetCharacterHeight(FS_SMALL);
                uint columns = this->GetNumberColumnsLegend(wi->current_x);
                uint number_of_rows = this->GetNumberRowsLegend(columns);
                if (line >= number_of_rows) return -1;

                bool rtl = _current_text_dir == TD_RTL;
                int x = pt.x - wi->pos_x;
                if (rtl) x = wi->current_x - x;
                uint column = (x - WidgetDimensions::scaled.framerect.left) / this->column_width;

                return (column * number_of_rows) + line;
        }

        /** Update all the links on the map. */
        void UpdateLinks()
        {
                if (this->map_type == SMT_LINKSTATS) {
                        CompanyMask company_mask = this->GetOverlayCompanyMask();
                        if (this->overlay->GetCompanyMask() != company_mask) {
                                this->overlay->SetCompanyMask(company_mask);
                        } else {
                                this->overlay->SetDirty();
                        }
                }
        }

        /** Blink the industries (if hover over an industry). */
        void Blink()
        {
                if (_smallmap_industry_highlight == INVALID_INDUSTRYTYPE) return;

                _smallmap_industry_highlight_state = !_smallmap_industry_highlight_state;

                this->UpdateLinks();
                this->SetDirty();
        }

        /** Force a full refresh of the map. */
        void ForceRefresh()
        {
                if (_smallmap_industry_highlight != INVALID_INDUSTRYTYPE) return;

                this->UpdateLinks();
                this->SetDirty();
        }

public:
        friend class NWidgetSmallmapDisplay;

        SmallMapWindow(WindowDesc &desc, int window_number) : Window(desc)
        {
                _smallmap_industry_highlight = INVALID_INDUSTRYTYPE;
                this->overlay = std::make_unique<LinkGraphOverlay>(this, WID_SM_MAP, 0, this->GetOverlayCompanyMask(), 1);
                this->CreateNestedTree();
                this->LowerWidget(WID_SM_CONTOUR + this->map_type);

                this->RebuildColourIndexIfNecessary();

                this->SetWidgetLoweredState(WID_SM_SHOW_HEIGHT, _smallmap_show_heightmap);

                this->SetWidgetLoweredState(WID_SM_TOGGLETOWNNAME, this->show_towns);
                this->SetWidgetLoweredState(WID_SM_SHOW_IND_NAMES, this->show_ind_names);

                this->SetupWidgetData();
                this->FinishInitNested(window_number);

                this->SetZoomLevel(ZLC_INITIALIZE, nullptr);
                this->SmallMapCenterOnCurrentPos();
                this->SetOverlayCargoMask();
        }

        /**
         * Center the small map on the current center of the viewport.
         */
        void SmallMapCenterOnCurrentPos()
        {
                const Viewport *vp = GetMainWindow()->viewport;
                Point viewport_center = InverseRemapCoords2(vp->virtual_left + vp->virtual_width / 2, vp->virtual_top + vp->virtual_height / 2);

                int sub;
                const NWidgetBase *wid = this->GetWidget<NWidgetBase>(WID_SM_MAP);
                Point sxy = this->ComputeScroll(viewport_center.x / (int)TILE_SIZE, viewport_center.y / (int)TILE_SIZE,
                                std::max(0, (int)wid->current_x / 2 - 2), wid->current_y / 2, &sub);
                this->SetNewScroll(sxy.x, sxy.y, sub);
                this->SetDirty();
        }

        /**
         * Get the center of the given station as point on the screen in the smallmap window.
         * @param st Station to find in the smallmap.
         * @return Point with coordinates of the station.
         */
        Point GetStationMiddle(const Station *st) const
        {
                int x = CenterBounds(st->rect.left, st->rect.right, 0);
                int y = CenterBounds(st->rect.top, st->rect.bottom, 0);
                Point ret = this->RemapTile(x, y);

                /* Same magic 3 as in DrawVehicles; that's where I got it from.
                 * No idea what it is, but without it the result looks bad.
                 */
                ret.x -= 3 + this->subscroll;
                return ret;
        }

        void Close([[maybe_unused]] int data) override
        {
                this->BreakIndustryChainLink();
                this->Window::Close();
        }

        void SetStringParameters(WidgetID widget) const override
        {
                switch (widget) {
                        case WID_SM_CAPTION:
                                SetDParam(0, STR_SMALLMAP_TYPE_CONTOURS + this->map_type);
                                break;
                }
        }

        void OnInit() override
        {
                uint min_width = 0;
                this->min_number_of_columns = INDUSTRY_MIN_NUMBER_OF_COLUMNS;
                this->min_number_of_fixed_rows = lengthof(_linkstat_colours_in_legenda);
                for (uint i = 0; i < lengthof(_legend_table); i++) {
                        uint height = 0;
                        uint num_columns = 1;
                        for (const LegendAndColour *tbl = _legend_table[i]; !tbl->end; ++tbl) {
                                StringID str;
                                if (i == SMT_INDUSTRY) {
                                        SetDParam(0, tbl->legend);
                                        SetDParam(1, IndustryPool::MAX_SIZE);
                                        str = STR_SMALLMAP_INDUSTRY;
                                } else if (i == SMT_LINKSTATS) {
                                        SetDParam(0, tbl->legend);
                                        str = STR_SMALLMAP_LINKSTATS;
                                } else if (i == SMT_OWNER) {
                                        if (tbl->company != INVALID_COMPANY) {
                                                if (!Company::IsValidID(tbl->company)) {
                                                        /* Rebuild the owner legend. */
                                                        BuildOwnerLegend();
                                                        this->OnInit();
                                                        return;
                                                }
                                                /* Non-fixed legend entries for the owner view. */
                                                SetDParam(0, tbl->company);
                                                str = STR_SMALLMAP_COMPANY;
                                        } else {
                                                str = tbl->legend;
                                        }
                                } else {
                                        if (tbl->col_break) {
                                                this->min_number_of_fixed_rows = std::max(this->min_number_of_fixed_rows, height);
                                                height = 0;
                                                num_columns++;
                                        }
                                        height++;
                                        str = tbl->legend;
                                }
                                min_width = std::max(GetStringBoundingBox(str).width, min_width);
                        }
                        this->min_number_of_fixed_rows = std::max(this->min_number_of_fixed_rows, height);
                        this->min_number_of_columns = std::max(this->min_number_of_columns, num_columns);
                }

                /* Width of the legend blob. */
                this->legend_width = GetCharacterHeight(FS_SMALL) * 9 / 6;

                /* The width of a column is the minimum width of all texts + the size of the blob + some spacing */
                this->column_width = min_width + WidgetDimensions::scaled.hsep_normal + this->legend_width + WidgetDimensions::scaled.framerect.Horizontal();

                /* Cached string widths of industry names in the smallmap. Calculation is deferred to DrawIndustryNames(). */
                std::fill(std::begin(_industry_to_name_string_width), std::end(_industry_to_name_string_width), 0);
        }

        void OnPaint() override
        {
                if (this->map_type == SMT_OWNER) {
                        for (const LegendAndColour *tbl = _legend_table[this->map_type]; !tbl->end; ++tbl) {
                                if (tbl->company != INVALID_COMPANY && !Company::IsValidID(tbl->company)) {
                                        /* Rebuild the owner legend. */
                                        BuildOwnerLegend();
                                        this->InvalidateData(1);
                                        break;
                                }
                        }
                }

                this->DrawWidgets();
        }

        void DrawWidget(const Rect &r, WidgetID widget) const override
        {
                switch (widget) {
                        case WID_SM_MAP: {
                                Rect ir = r.Shrink(WidgetDimensions::scaled.bevel);
                                DrawPixelInfo new_dpi;
                                if (!FillDrawPixelInfo(&new_dpi, ir)) return;
                                this->DrawSmallMap(&new_dpi);
                                break;
                        }

                        case WID_SM_LEGEND: {
                                uint columns = this->GetNumberColumnsLegend(r.Width());
                                uint number_of_rows = this->GetNumberRowsLegend(columns);
                                bool rtl = _current_text_dir == TD_RTL;
                                uint i = 0; // Row counter for industry legend.
                                uint row_height = GetCharacterHeight(FS_SMALL);
                                int padding = ScaleGUITrad(1);

                                Rect origin = r.WithWidth(this->column_width, rtl).Shrink(WidgetDimensions::scaled.framerect).WithHeight(row_height);
                                Rect text = origin.Indent(this->legend_width + WidgetDimensions::scaled.hsep_normal, rtl);
                                Rect icon = origin.WithWidth(this->legend_width, rtl).Shrink(0, padding, 0, 0);

                                StringID string = STR_NULL;
                                switch (this->map_type) {
                                        case SMT_INDUSTRY:
                                                string = STR_SMALLMAP_INDUSTRY;
                                                break;
                                        case SMT_LINKSTATS:
                                                string = STR_SMALLMAP_LINKSTATS;
                                                break;
                                        case SMT_OWNER:
                                                string = STR_SMALLMAP_COMPANY;
                                                break;
                                        default:
                                                break;
                                }

                                for (const LegendAndColour *tbl = _legend_table[this->map_type]; !tbl->end; ++tbl) {
                                        if (tbl->col_break || ((this->map_type == SMT_INDUSTRY || this->map_type == SMT_OWNER || this->map_type == SMT_LINKSTATS) && i++ >= number_of_rows)) {
                                                /* Column break needed, continue at top, COLUMN_WIDTH pixels
                                                 * (one "row") to the right. */
                                                int x = rtl ? -(int)this->column_width : this->column_width;
                                                int y = origin.top - text.top;
                                                text = text.Translate(x, y);
                                                icon = icon.Translate(x, y);
                                                i = 1;
                                        }

                                        uint8_t legend_colour = tbl->colour;

                                        switch (this->map_type) {
                                                case SMT_INDUSTRY:
                                                        /* Industry name must be formatted, since it's not in tiny font in the specs.
                                                         * So, draw with a parameter and use the STR_SMALLMAP_INDUSTRY string, which is tiny font */
                                                        SetDParam(0, tbl->legend);
                                                        SetDParam(1, Industry::GetIndustryTypeCount(tbl->type));
                                                        if (tbl->show_on_map && tbl->type == _smallmap_industry_highlight) {
                                                                legend_colour = _smallmap_industry_highlight_state ? PC_WHITE : PC_BLACK;
                                                        }
                                                        [[fallthrough]];

                                                case SMT_LINKSTATS:
                                                        SetDParam(0, tbl->legend);
                                                        [[fallthrough]];

                                                case SMT_OWNER:
                                                        if (this->map_type != SMT_OWNER || tbl->company != INVALID_COMPANY) {
                                                                if (this->map_type == SMT_OWNER) SetDParam(0, tbl->company);
                                                                if (!tbl->show_on_map) {
                                                                        /* Simply draw the string, not the black border of the legend colour.
                                                                         * This will enforce the idea of the disabled item */
                                                                        DrawString(text, string, TC_GREY);
                                                                } else {
                                                                        DrawString(text, string, TC_BLACK);
                                                                        GfxFillRect(icon, PC_BLACK); // Outer border of the legend colour
                                                                }
                                                                break;
                                                        }
                                                        [[fallthrough]];

                                                default:
                                                        if (this->map_type == SMT_CONTOUR) SetDParam(0, tbl->height * TILE_HEIGHT_STEP);
                                                        /* Anything that is not an industry or a company is using normal process */
                                                        GfxFillRect(icon, PC_BLACK);
                                                        DrawString(text, tbl->legend);
                                                        break;
                                        }
                                        GfxFillRect(icon.Shrink(WidgetDimensions::scaled.bevel), legend_colour); // Legend colour

                                        text = text.Translate(0, row_height);
                                        icon = icon.Translate(0, row_height);
                                }
                        }
                }
        }

        void OnClick([[maybe_unused]] Point pt, WidgetID widget, [[maybe_unused]] int click_count) override
        {
                switch (widget) {
                        case WID_SM_MAP: { // Map window
                                if (click_count > 0) this->mouse_capture_widget = widget;

                                const NWidgetBase *wid = this->GetWidget<NWidgetBase>(WID_SM_MAP);
                                Window *w = GetMainWindow();
                                int sub;
                                pt = this->PixelToTile(pt.x - wid->pos_x, pt.y - wid->pos_y, &sub);
                                ScrollWindowTo(this->scroll_x + pt.x * TILE_SIZE, this->scroll_y + pt.y * TILE_SIZE, -1, w);

                                this->SetDirty();
                                break;
                        }

                        case WID_SM_ZOOM_IN:
                        case WID_SM_ZOOM_OUT: {
                                const NWidgetBase *wid = this->GetWidget<NWidgetBase>(WID_SM_MAP);
                                Point zoom_pt = { (int)wid->current_x / 2, (int)wid->current_y / 2};
                                this->SetZoomLevel((widget == WID_SM_ZOOM_IN) ? ZLC_ZOOM_IN : ZLC_ZOOM_OUT, &zoom_pt);
                                if (_settings_client.sound.click_beep) SndPlayFx(SND_15_BEEP);
                                break;
                        }

                        case WID_SM_CONTOUR:    // Show land contours
                        case WID_SM_VEHICLES:   // Show vehicles
                        case WID_SM_INDUSTRIES: // Show industries
                        case WID_SM_LINKSTATS:  // Show route map
                        case WID_SM_ROUTES:     // Show transport routes
                        case WID_SM_VEGETATION: // Show vegetation
                        case WID_SM_OWNERS:     // Show land owners
                                this->SwitchMapType((SmallMapType)(widget - WID_SM_CONTOUR));
                                if (_settings_client.sound.click_beep) SndPlayFx(SND_15_BEEP);
                                break;

                        case WID_SM_CENTERMAP: // Center the smallmap again
                                this->SmallMapCenterOnCurrentPos();
                                this->HandleButtonClick(WID_SM_CENTERMAP);
                                if (_settings_client.sound.click_beep) SndPlayFx(SND_15_BEEP);
                                break;

                        case WID_SM_TOGGLETOWNNAME: // Toggle town names
                                this->show_towns = !this->show_towns;
                                this->SetWidgetLoweredState(WID_SM_TOGGLETOWNNAME, this->show_towns);

                                this->SetDirty();
                                if (_settings_client.sound.click_beep) SndPlayFx(SND_15_BEEP);
                                break;

                        case WID_SM_SHOW_IND_NAMES: // Toggle industry names
                                this->show_ind_names = !this->show_ind_names;
                                this->SetWidgetLoweredState(WID_SM_SHOW_IND_NAMES, this->show_ind_names);

                                this->SetDirty();
                                if (_settings_client.sound.click_beep) SndPlayFx(SND_15_BEEP);
                                break;

                        case WID_SM_LEGEND: // Legend
                                if (this->map_type == SMT_INDUSTRY || this->map_type == SMT_LINKSTATS || this->map_type == SMT_OWNER) {
                                        int click_pos = this->GetPositionOnLegend(pt);
                                        if (click_pos < 0) break;

                                        /* If industry type small map*/
                                        if (this->map_type == SMT_INDUSTRY) {
                                                /* If click on industries label, find right industry type and enable/disable it. */
                                                if (click_pos < _smallmap_industry_count) {
                                                        this->SelectLegendItem(click_pos, _legend_from_industries, _smallmap_industry_count);
                                                }
                                        } else if (this->map_type == SMT_LINKSTATS) {
                                                if (click_pos < _smallmap_cargo_count) {
                                                        this->SelectLegendItem(click_pos, _legend_linkstats, _smallmap_cargo_count);
                                                        this->SetOverlayCargoMask();
                                                }
                                        } else if (this->map_type == SMT_OWNER) {
                                                if (click_pos < _smallmap_company_count) {
                                                        this->SelectLegendItem(click_pos, _legend_land_owners, _smallmap_company_count, NUM_NO_COMPANY_ENTRIES);
                                                }
                                        }
                                        this->SetDirty();
                                }
                                break;

                        case WID_SM_ENABLE_ALL:
                        case WID_SM_DISABLE_ALL: {
                                LegendAndColour *tbl = nullptr;
                                switch (this->map_type) {
                                        case SMT_INDUSTRY:
                                                tbl = _legend_from_industries;
                                                this->BreakIndustryChainLink();
                                                break;
                                        case SMT_OWNER:
                                                tbl = &(_legend_land_owners[NUM_NO_COMPANY_ENTRIES]);
                                                break;
                                        case SMT_LINKSTATS:
                                                tbl = _legend_linkstats;
                                                break;
                                        default:
                                                NOT_REACHED();
                                }
                                for (;!tbl->end && tbl->legend != STR_LINKGRAPH_LEGEND_UNUSED; ++tbl) {
                                        tbl->show_on_map = (widget == WID_SM_ENABLE_ALL);
                                }
                                if (this->map_type == SMT_LINKSTATS) this->SetOverlayCargoMask();
                                this->SetDirty();
                                break;
                        }

                        case WID_SM_SHOW_HEIGHT: // Enable/disable showing of heightmap.
                                _smallmap_show_heightmap = !_smallmap_show_heightmap;
                                this->SetWidgetLoweredState(WID_SM_SHOW_HEIGHT, _smallmap_show_heightmap);
                                this->SetDirty();
                                break;
                }
        }

        /**
         * Some data on this window has become invalid.
         * @param data Information about the changed data.
         * - data = 0: Displayed industries at the industry chain window have changed.
         * - data = 1: Companies have changed.
         * - data = 2: Cheat changing the maximum heightlevel has been used, rebuild our heightlevel-to-colour index
         * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
         */
        void OnInvalidateData(int data = 0, bool gui_scope = true) override
        {
                if (!gui_scope) return;

                switch (data) {
                        case 1:
                                /* The owner legend has already been rebuilt. */
                                this->ReInit();
                                break;

                        case 0: {
                                extern std::bitset<NUM_INDUSTRYTYPES> _displayed_industries;
                                if (this->map_type != SMT_INDUSTRY) this->SwitchMapType(SMT_INDUSTRY);

                                for (int i = 0; i != _smallmap_industry_count; i++) {
                                        _legend_from_industries[i].show_on_map = _displayed_industries.test(_legend_from_industries[i].type);
                                }
                                break;
                        }

                        case 2:
                                this->RebuildColourIndexIfNecessary();
                                break;

                        default: NOT_REACHED();
                }
                this->SetDirty();
        }

        bool OnRightClick(Point, WidgetID widget) override
        {
                if (widget != WID_SM_MAP || _scrolling_viewport) return false;

                _scrolling_viewport = true;
                return true;
        }

        void OnMouseWheel(int wheel) override
        {
                if (_settings_client.gui.scrollwheel_scrolling != SWS_OFF) {
                        const NWidgetBase *wid = this->GetWidget<NWidgetBase>(WID_SM_MAP);
                        int cursor_x = _cursor.pos.x - this->left - wid->pos_x;
                        int cursor_y = _cursor.pos.y - this->top  - wid->pos_y;
                        if (IsInsideMM(cursor_x, 0, wid->current_x) && IsInsideMM(cursor_y, 0, wid->current_y)) {
                                Point pt = {cursor_x, cursor_y};
                                this->SetZoomLevel((wheel < 0) ? ZLC_ZOOM_IN : ZLC_ZOOM_OUT, &pt);
                        }
                }
        }

        void OnScroll(Point delta) override
        {
                if (_settings_client.gui.scroll_mode == VSM_VIEWPORT_RMB_FIXED || _settings_client.gui.scroll_mode == VSM_MAP_RMB_FIXED) _cursor.fix_at = true;

                /* While tile is at (delta.x, delta.y)? */
                int sub;
                Point pt = this->PixelToTile(delta.x, delta.y, &sub);
                this->SetNewScroll(this->scroll_x + pt.x * TILE_SIZE, this->scroll_y + pt.y * TILE_SIZE, sub);

                this->SetDirty();
        }

        void OnMouseOver([[maybe_unused]] Point pt, WidgetID widget) override
        {
                IndustryType new_highlight = INVALID_INDUSTRYTYPE;
                if (widget == WID_SM_LEGEND && this->map_type == SMT_INDUSTRY) {
                        int industry_pos = GetPositionOnLegend(pt);
                        if (industry_pos >= 0 && industry_pos < _smallmap_industry_count) {
                                new_highlight = _legend_from_industries[industry_pos].type;
                        }
                }
                if (new_highlight != _smallmap_industry_highlight) {
                        _smallmap_industry_highlight = new_highlight;
                        _smallmap_industry_highlight_state = true;
                        this->SetDirty();
                }
        }

};

SmallMapType SmallMapWindow::map_type = SMT_CONTOUR;
bool SmallMapWindow::show_towns = true;
bool SmallMapWindow::show_ind_names = false;
int SmallMapWindow::map_height_limit = -1;

/**
 * Custom container class for displaying smallmap with a vertically resizing legend panel.
 * The legend panel has a smallest height that depends on its width. Standard containers cannot handle this case.
 *
 * @note The container assumes it has two children, the first is the display, the second is the bar with legends and selection image buttons.
 *       Both children should be both horizontally and vertically resizable and horizontally fillable.
 *       The bar should have a minimal size with a zero-size legends display. Child padding is not supported.
 */
class NWidgetSmallmapDisplay : public NWidgetContainer {
        const SmallMapWindow *smallmap_window; ///< Window manager instance.
public:
        NWidgetSmallmapDisplay() : NWidgetContainer(NWID_VERTICAL)
        {
                this->smallmap_window = nullptr;
        }

        void SetupSmallestSize(Window *w) override
        {
                assert(this->children.size() == 2);
                NWidgetBase *display = this->children.front().get();
                NWidgetBase *bar = this->children.back().get();

                display->SetupSmallestSize(w);
                bar->SetupSmallestSize(w);

                this->smallmap_window = dynamic_cast<SmallMapWindow *>(w);
                assert(this->smallmap_window != nullptr);
                this->smallest_x = std::max(display->smallest_x, bar->smallest_x + smallmap_window->GetMinLegendWidth());
                this->smallest_y = display->smallest_y + std::max(bar->smallest_y, smallmap_window->GetLegendHeight(smallmap_window->min_number_of_columns));
                this->fill_x = std::max(display->fill_x, bar->fill_x);
                this->fill_y = (display->fill_y == 0 && bar->fill_y == 0) ? 0 : std::min(display->fill_y, bar->fill_y);
                this->resize_x = std::max(display->resize_x, bar->resize_x);
                this->resize_y = std::min(display->resize_y, bar->resize_y);
                this->ApplyAspectRatio();
        }

        void AssignSizePosition(SizingType sizing, int x, int y, uint given_width, uint given_height, bool rtl) override
        {
                this->pos_x = x;
                this->pos_y = y;
                this->current_x = given_width;
                this->current_y = given_height;

                assert(this->children.size() == 2);
                NWidgetBase *display = this->children.front().get();
                NWidgetBase *bar = this->children.back().get();

                if (sizing == ST_SMALLEST) {
                        this->smallest_x = given_width;
                        this->smallest_y = given_height;
                        /* Make display and bar exactly equal to their minimal size. */
                        display->AssignSizePosition(ST_SMALLEST, x, y, display->smallest_x, display->smallest_y, rtl);
                        bar->AssignSizePosition(ST_SMALLEST, x, y + display->smallest_y, bar->smallest_x, bar->smallest_y, rtl);
                }

                uint bar_height = std::max(bar->smallest_y, this->smallmap_window->GetLegendHeight(this->smallmap_window->GetNumberColumnsLegend(given_width - bar->smallest_x)));
                uint display_height = given_height - bar_height;
                display->AssignSizePosition(ST_RESIZE, x, y, given_width, display_height, rtl);
                bar->AssignSizePosition(ST_RESIZE, x, y + display_height, given_width, bar_height, rtl);
        }
};

/** Widget parts of the smallmap display. */
static constexpr NWidgetPart _nested_smallmap_display[] = {
        NWidget(WWT_PANEL, COLOUR_BROWN, WID_SM_MAP_BORDER),
                NWidget(WWT_INSET, COLOUR_BROWN, WID_SM_MAP), SetMinimalSize(346, 140), SetResize(1, 1), SetPadding(2, 2, 2, 2), EndContainer(),
        EndContainer(),
};

/** Widget parts of the smallmap legend bar + image buttons. */
static constexpr NWidgetPart _nested_smallmap_bar[] = {
        NWidget(WWT_PANEL, COLOUR_BROWN),
                NWidget(NWID_HORIZONTAL),
                        NWidget(WWT_EMPTY, INVALID_COLOUR, WID_SM_LEGEND), SetResize(1, 1),
                        NWidget(NWID_VERTICAL),
                                /* Top button row. */
                                NWidget(NWID_HORIZONTAL, NC_EQUALSIZE),
                                        NWidget(WWT_PUSHIMGBTN, COLOUR_BROWN, WID_SM_ZOOM_IN),
                                                        SetDataTip(SPR_IMG_ZOOMIN, STR_TOOLBAR_TOOLTIP_ZOOM_THE_VIEW_IN), SetFill(1, 1),
                                        NWidget(WWT_PUSHIMGBTN, COLOUR_BROWN, WID_SM_CENTERMAP),
                                                        SetDataTip(SPR_IMG_SMALLMAP, STR_SMALLMAP_CENTER), SetFill(1, 1),
                                        NWidget(WWT_IMGBTN, COLOUR_BROWN, WID_SM_BLANK),
                                                        SetDataTip(SPR_EMPTY, STR_NULL), SetFill(1, 1),
                                        NWidget(WWT_IMGBTN, COLOUR_BROWN, WID_SM_CONTOUR),
                                                        SetDataTip(SPR_IMG_SHOW_COUNTOURS, STR_SMALLMAP_TOOLTIP_SHOW_LAND_CONTOURS_ON_MAP), SetFill(1, 1),
                                        NWidget(WWT_IMGBTN, COLOUR_BROWN, WID_SM_VEHICLES),
                                                        SetDataTip(SPR_IMG_SHOW_VEHICLES, STR_SMALLMAP_TOOLTIP_SHOW_VEHICLES_ON_MAP), SetFill(1, 1),
                                        NWidget(WWT_IMGBTN, COLOUR_BROWN, WID_SM_INDUSTRIES),
                                                        SetDataTip(SPR_IMG_INDUSTRY, STR_SMALLMAP_TOOLTIP_SHOW_INDUSTRIES_ON_MAP), SetFill(1, 1),
                                EndContainer(),
                                /* Bottom button row. */
                                NWidget(NWID_HORIZONTAL, NC_EQUALSIZE),
                                        NWidget(WWT_PUSHIMGBTN, COLOUR_BROWN, WID_SM_ZOOM_OUT),
                                                        SetDataTip(SPR_IMG_ZOOMOUT, STR_TOOLBAR_TOOLTIP_ZOOM_THE_VIEW_OUT), SetFill(1, 1),
                                        NWidget(WWT_IMGBTN, COLOUR_BROWN, WID_SM_TOGGLETOWNNAME),
                                                        SetDataTip(SPR_IMG_TOWN, STR_SMALLMAP_TOOLTIP_TOGGLE_TOWN_NAMES_ON_OFF), SetFill(1, 1),
                                        NWidget(WWT_IMGBTN, COLOUR_BROWN, WID_SM_LINKSTATS),
                                                        SetDataTip(SPR_IMG_CARGOFLOW, STR_SMALLMAP_TOOLTIP_SHOW_LINK_STATS_ON_MAP), SetFill(1, 1),
                                        NWidget(WWT_IMGBTN, COLOUR_BROWN, WID_SM_ROUTES),
                                                        SetDataTip(SPR_IMG_SHOW_ROUTES, STR_SMALLMAP_TOOLTIP_SHOW_TRANSPORT_ROUTES_ON), SetFill(1, 1),
                                        NWidget(WWT_IMGBTN, COLOUR_BROWN, WID_SM_VEGETATION),
                                                        SetDataTip(SPR_IMG_PLANTTREES, STR_SMALLMAP_TOOLTIP_SHOW_VEGETATION_ON_MAP), SetFill(1, 1),
                                        NWidget(WWT_IMGBTN, COLOUR_BROWN, WID_SM_OWNERS),
                                                        SetDataTip(SPR_IMG_COMPANY_GENERAL, STR_SMALLMAP_TOOLTIP_SHOW_LAND_OWNERS_ON_MAP), SetFill(1, 1),
                                EndContainer(),
                                NWidget(NWID_SPACER), SetResize(0, 1),
                        EndContainer(),
                EndContainer(),
        EndContainer(),
};

static std::unique_ptr<NWidgetBase> SmallMapDisplay()
{
        std::unique_ptr<NWidgetBase> map_display = std::make_unique<NWidgetSmallmapDisplay>();

        map_display = MakeNWidgets(_nested_smallmap_display, std::move(map_display));
        map_display = MakeNWidgets(_nested_smallmap_bar, std::move(map_display));
        return map_display;
}

static constexpr NWidgetPart _nested_smallmap_widgets[] = {
        NWidget(NWID_HORIZONTAL),
                NWidget(WWT_CLOSEBOX, COLOUR_BROWN),
                NWidget(WWT_CAPTION, COLOUR_BROWN, WID_SM_CAPTION), SetDataTip(STR_SMALLMAP_CAPTION, STR_TOOLTIP_WINDOW_TITLE_DRAG_THIS),
                NWidget(WWT_SHADEBOX, COLOUR_BROWN),
                NWidget(WWT_DEFSIZEBOX, COLOUR_BROWN),
                NWidget(WWT_STICKYBOX, COLOUR_BROWN),
        EndContainer(),
        NWidgetFunction(SmallMapDisplay), // Smallmap display and legend bar + image buttons.
        /* Bottom button row and resize box. */
        NWidget(NWID_HORIZONTAL),
                NWidget(NWID_SELECTION, INVALID_COLOUR, WID_SM_SELECT_BUTTONS),
                        NWidget(NWID_HORIZONTAL, NC_EQUALSIZE),
                                NWidget(WWT_PUSHTXTBTN, COLOUR_BROWN, WID_SM_ENABLE_ALL), SetDataTip(STR_SMALLMAP_ENABLE_ALL, STR_NULL),
                                NWidget(WWT_PUSHTXTBTN, COLOUR_BROWN, WID_SM_DISABLE_ALL), SetDataTip(STR_SMALLMAP_DISABLE_ALL, STR_NULL),
                                NWidget(WWT_TEXTBTN, COLOUR_BROWN, WID_SM_SHOW_HEIGHT), SetDataTip(STR_SMALLMAP_SHOW_HEIGHT, STR_SMALLMAP_TOOLTIP_SHOW_HEIGHT),

                                /* 'show industry names' button and container. Only shown for the industry map type. */
                                NWidget(NWID_SELECTION, INVALID_COLOUR, WID_SM_SHOW_IND_NAMES_SEL),
                                        NWidget(WWT_TEXTBTN, COLOUR_BROWN, WID_SM_SHOW_IND_NAMES), SetDataTip(STR_SMALLMAP_SHOW_INDUSTRY_NAMES, STR_SMALLMAP_TOOLTIP_SHOW_INDUSTRY_NAMES),
                                EndContainer(),

                                NWidget(WWT_PANEL, COLOUR_BROWN), SetFill(1, 0), SetResize(1, 0),
                                EndContainer(),
                        EndContainer(),
                        NWidget(WWT_PANEL, COLOUR_BROWN), SetFill(1, 0), SetResize(1, 0),
                        EndContainer(),
                EndContainer(),
                NWidget(WWT_RESIZEBOX, COLOUR_BROWN),
        EndContainer(),
};

static WindowDesc _smallmap_desc(
        WDP_AUTO, "smallmap", 484, 314,
        WC_SMALLMAP, WC_NONE,
        0,
        _nested_smallmap_widgets
);

/**
 * Show the smallmap window.
 */
void ShowSmallMap()
{
        AllocateWindowDescFront<SmallMapWindow>(_smallmap_desc, 0);
}

/**
 * Scrolls the main window to given coordinates.
 * @param x x coordinate
 * @param y y coordinate
 * @param z z coordinate; -1 to scroll to terrain height
 * @param instant scroll instantly (meaningful only when smooth_scrolling is active)
 * @return did the viewport position change?
 */
bool ScrollMainWindowTo(int x, int y, int z, bool instant)
{
        bool res = ScrollWindowTo(x, y, z, GetMainWindow(), instant);

        /* If a user scrolls to a tile (via what way what so ever) and already is on
         * that tile (e.g.: pressed twice), move the smallmap to that location,
         * so you directly see where you are on the smallmap. */

        if (res) return res;

        SmallMapWindow *w = dynamic_cast<SmallMapWindow*>(FindWindowById(WC_SMALLMAP, 0));
        if (w != nullptr) w->SmallMapCenterOnCurrentPos();

        return res;
}

/**
 * Determine the middle of a station in the smallmap window.
 * @param st The station we're looking for.
 * @return Middle point of the station in the smallmap window.
 */
Point GetSmallMapStationMiddle(const Window *w, const Station *st)
{
        return static_cast<const SmallMapWindow *>(w)->GetStationMiddle(st);
}