src/base_station_base.h

   1 /*
   2  * This file is part of OpenTTD.
   3  * 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.
   4  * 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.
   5  * 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/>.
   6  */
   7
   8 /** @file base_station_base.h Base classes/functions for base stations. */
   9
  10 #ifndef BASE_STATION_BASE_H
  11 #define BASE_STATION_BASE_H
  12
  13 #include "core/pool_type.hpp"
  14 #include "command_type.h"
  15 #include "viewport_type.h"
  16 #include "station_map.h"
  17
  18 typedef Pool<BaseStation, StationID, 32, 64000> StationPool;
  19 extern StationPool _station_pool;
  20
  21 struct StationSpecList {
  22         const StationSpec *spec;
  23         uint32 grfid;      ///< GRF ID of this custom station
  24         uint8  localidx;   ///< Station ID within GRF of station
  25 };
  26
  27
  28 /** StationRect - used to track station spread out rectangle - cheaper than scanning whole map */
  29 struct StationRect : public Rect {
  30         enum StationRectMode
  31         {
  32                 ADD_TEST = 0,
  33                 ADD_TRY,
  34                 ADD_FORCE
  35         };
  36
  37         StationRect();
  38         void MakeEmpty();
  39         bool PtInExtendedRect(int x, int y, int distance = 0) const;
  40         bool IsEmpty() const;
  41         CommandCost BeforeAddTile(TileIndex tile, StationRectMode mode);
  42         CommandCost BeforeAddRect(TileIndex tile, int w, int h, StationRectMode mode);
  43         bool AfterRemoveTile(BaseStation *st, TileIndex tile);
  44         bool AfterRemoveRect(BaseStation *st, TileArea ta);
  45
  46         static bool ScanForStationTiles(StationID st_id, int left_a, int top_a, int right_a, int bottom_a);
  47
  48         StationRect& operator = (const Rect &src);
  49 };
  50
  51 /** Base class for all station-ish types */
  52 struct BaseStation : StationPool::PoolItem<&_station_pool> {
  53         TileIndex xy;                   ///< Base tile of the station
  54         TrackedViewportSign sign;       ///< NOSAVE: Dimensions of sign
  55         byte delete_ctr;                ///< Delete counter. If greater than 0 then it is decremented until it reaches 0; the waypoint is then is deleted.
  56
  57         std::string name;               ///< Custom name
  58         StringID string_id;             ///< Default name (town area) of station
  59         mutable std::string cached_name; ///< NOSAVE: Cache of the resolved name of the station, if not using a custom name
  60
  61         Town *town;                     ///< The town this station is associated with
  62         Owner owner;                    ///< The owner of this station
  63         StationFacility facilities;     ///< The facilities that this station has
  64
  65         std::vector<StationSpecList> speclist; ///< List of rail station specs of this station.
  66
  67         Date build_date;                ///< Date of construction
  68
  69         uint16 random_bits;             ///< Random bits assigned to this station
  70         byte waiting_triggers;          ///< Waiting triggers (NewGRF) for this station
  71         uint8 cached_anim_triggers;     ///< NOSAVE: Combined animation trigger bitmask, used to determine if trigger processing should happen.
  72         CargoTypes cached_cargo_triggers; ///< NOSAVE: Combined cargo trigger bitmask
  73
  74         TileArea train_station;         ///< Tile area the train 'station' part covers
  75         StationRect rect;               ///< NOSAVE: Station spread out rectangle maintained by StationRect::xxx() functions
  76
  77         /**
  78          * Initialize the base station.
  79          * @param tile The location of the station sign
  80          */
  81         BaseStation(TileIndex tile) :
  82                 xy(tile),
  83                 train_station(INVALID_TILE, 0, 0)
  84         {
  85         }
  86
  87         virtual ~BaseStation();
  88
  89         /**
  90          * Check whether a specific tile belongs to this station.
  91          * @param tile the tile to check
  92          * @return true if the tile belongs to this station
  93          */
  94         virtual bool TileBelongsToRailStation(TileIndex tile) const = 0;
  95
  96         /**
  97          * Helper function to get a NewGRF variable that isn't implemented by the base class.
  98          * @param object the resolver object related to this query
  99          * @param variable that is queried
 100          * @param parameter parameter for that variable
 101          * @param available will return false if ever the variable asked for does not exist
 102          * @return the value stored in the corresponding variable
 103          */
 104         virtual uint32 GetNewGRFVariable(const struct ResolverObject &object, byte variable, byte parameter, bool *available) const = 0;
 105
 106         /**
 107          * Update the coordinated of the sign (as shown in the viewport).
 108          */
 109         virtual void UpdateVirtCoord() = 0;
 110
 111         inline const char *GetCachedName() const
 112         {
 113                 if (!this->name.empty()) return this->name.c_str();
 114                 if (this->cached_name.empty()) this->FillCachedName();
 115                 return this->cached_name.c_str();
 116         }
 117
 118         virtual void MoveSign(TileIndex new_xy)
 119         {
 120                 this->xy = new_xy;
 121                 this->UpdateVirtCoord();
 122         }
 123
 124         /**
 125          * Get the tile area for a given station type.
 126          * @param ta tile area to fill.
 127          * @param type the type of the area
 128          */
 129         virtual void GetTileArea(TileArea *ta, StationType type) const = 0;
 130
 131
 132         /**
 133          * Obtain the length of a platform
 134          * @pre tile must be a rail station tile
 135          * @param tile A tile that contains the platform in question
 136          * @return The length of the platform
 137          */
 138         virtual uint GetPlatformLength(TileIndex tile) const = 0;
 139
 140         /**
 141          * Determines the REMAINING length of a platform, starting at (and including)
 142          * the given tile.
 143          * @param tile the tile from which to start searching. Must be a rail station tile
 144          * @param dir The direction in which to search.
 145          * @return The platform length
 146          */
 147         virtual uint GetPlatformLength(TileIndex tile, DiagDirection dir) const = 0;
 148
 149         /**
 150          * Get the base station belonging to a specific tile.
 151          * @param tile The tile to get the base station from.
 152          * @return the station associated with that tile.
 153          */
 154         static inline BaseStation *GetByTile(TileIndex tile)
 155         {
 156                 return BaseStation::Get(GetStationIndex(tile));
 157         }
 158
 159         /**
 160          * Check whether the base station currently is in use; in use means
 161          * that it is not scheduled for deletion and that it still has some
 162          * facilities left.
 163          * @return true if still in use
 164          */
 165         inline bool IsInUse() const
 166         {
 167                 return (this->facilities & ~FACIL_WAYPOINT) != 0;
 168         }
 169
 170         static void PostDestructor(size_t index);
 171
 172 private:
 173         void FillCachedName() const;
 174 };
 175
 176 /**
 177  * Class defining several overloaded accessors so we don't
 178  * have to cast base stations that often
 179  */
 180 template <class T, bool Tis_waypoint>
 181 struct SpecializedStation : public BaseStation {
 182         static const StationFacility EXPECTED_FACIL = Tis_waypoint ? FACIL_WAYPOINT : FACIL_NONE; ///< Specialized type
 183
 184         /**
 185          * Set station type correctly
 186          * @param tile The base tile of the station.
 187          */
 188         inline SpecializedStation<T, Tis_waypoint>(TileIndex tile) :
 189                         BaseStation(tile)
 190         {
 191                 this->facilities = EXPECTED_FACIL;
 192         }
 193
 194         /**
 195          * Helper for checking whether the given station is of this type.
 196          * @param st the station to check.
 197          * @return true if the station is the type we expect it to be.
 198          */
 199         static inline bool IsExpected(const BaseStation *st)
 200         {
 201                 return (st->facilities & FACIL_WAYPOINT) == EXPECTED_FACIL;
 202         }
 203
 204         /**
 205          * Tests whether given index is a valid index for station of this type
 206          * @param index tested index
 207          * @return is this index valid index of T?
 208          */
 209         static inline bool IsValidID(size_t index)
 210         {
 211                 return BaseStation::IsValidID(index) && IsExpected(BaseStation::Get(index));
 212         }
 213
 214         /**
 215          * Gets station with given index
 216          * @return pointer to station with given index casted to T *
 217          */
 218         static inline T *Get(size_t index)
 219         {
 220                 return (T *)BaseStation::Get(index);
 221         }
 222
 223         /**
 224          * Returns station if the index is a valid index for this station type
 225          * @return pointer to station with given index if it's a station of this type
 226          */
 227         static inline T *GetIfValid(size_t index)
 228         {
 229                 return IsValidID(index) ? Get(index) : nullptr;
 230         }
 231
 232         /**
 233          * Get the station belonging to a specific tile.
 234          * @param tile The tile to get the station from.
 235          * @return the station associated with that tile.
 236          */
 237         static inline T *GetByTile(TileIndex tile)
 238         {
 239                 return GetIfValid(GetStationIndex(tile));
 240         }
 241
 242         /**
 243          * Converts a BaseStation to SpecializedStation with type checking.
 244          * @param st BaseStation pointer
 245          * @return pointer to SpecializedStation
 246          */
 247         static inline T *From(BaseStation *st)
 248         {
 249                 assert(IsExpected(st));
 250                 return (T *)st;
 251         }
 252
 253         /**
 254          * Converts a const BaseStation to const SpecializedStation with type checking.
 255          * @param st BaseStation pointer
 256          * @return pointer to SpecializedStation
 257          */
 258         static inline const T *From(const BaseStation *st)
 259         {
 260                 assert(IsExpected(st));
 261                 return (const T *)st;
 262         }
 263
 264         /**
 265          * Returns an iterable ensemble of all valid stations of type T
 266          * @param from index of the first station to consider
 267          * @return an iterable ensemble of all valid stations of type T
 268          */
 269         static Pool::IterateWrapper<T> Iterate(size_t from = 0) { return Pool::IterateWrapper<T>(from); }
 270 };
 271
 272 #endif /* BASE_STATION_BASE_H */