src/newgrf_station.cpp

   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 newgrf_station.cpp Functions for dealing with station classes and custom stations. */
   9
  10 #include "stdafx.h"
  11 #include "debug.h"
  12 #include "station_base.h"
  13 #include "waypoint_base.h"
  14 #include "roadstop_base.h"
  15 #include "newgrf_cargo.h"
  16 #include "newgrf_station.h"
  17 #include "newgrf_spritegroup.h"
  18 #include "newgrf_sound.h"
  19 #include "newgrf_railtype.h"
  20 #include "town.h"
  21 #include "newgrf_town.h"
  22 #include "company_func.h"
  23 #include "tunnelbridge_map.h"
  24 #include "newgrf_animation_base.h"
  25 #include "newgrf_class_func.h"
  26
  27 #include "safeguards.h"
  28
  29
  30 template <typename Tspec, typename Tid, Tid Tmax>
  31 /* static */ void NewGRFClass<Tspec, Tid, Tmax>::InsertDefaults()
  32 {
  33         /* Set up initial data */
  34         classes[0].global_id = 'DFLT';
  35         classes[0].name = STR_STATION_CLASS_DFLT;
  36         classes[0].Insert(nullptr);
  37
  38         classes[1].global_id = 'WAYP';
  39         classes[1].name = STR_STATION_CLASS_WAYP;
  40         classes[1].Insert(nullptr);
  41 }
  42
  43 template <typename Tspec, typename Tid, Tid Tmax>
  44 bool NewGRFClass<Tspec, Tid, Tmax>::IsUIAvailable(uint index) const
  45 {
  46         return true;
  47 }
  48
  49 INSTANTIATE_NEWGRF_CLASS_METHODS(StationClass, StationSpec, StationClassID, STAT_CLASS_MAX)
  50
  51 static const uint NUM_STATIONSSPECS_PER_STATION = 255; ///< Maximum number of parts per station.
  52
  53 enum TriggerArea {
  54         TA_TILE,
  55         TA_PLATFORM,
  56         TA_WHOLE,
  57 };
  58
  59 struct ETileArea : TileArea {
  60         ETileArea(const BaseStation *st, TileIndex tile, TriggerArea ta)
  61         {
  62                 switch (ta) {
  63                         default: NOT_REACHED();
  64
  65                         case TA_TILE:
  66                                 this->tile = tile;
  67                                 this->w    = 1;
  68                                 this->h    = 1;
  69                                 break;
  70
  71                         case TA_PLATFORM: {
  72                                 TileIndex start, end;
  73                                 Axis axis = GetRailStationAxis(tile);
  74                                 TileIndexDiff delta = TileOffsByDiagDir(AxisToDiagDir(axis));
  75
  76                                 for (end = tile; IsRailStationTile(end + delta) && IsCompatibleTrainStationTile(end + delta, tile); end += delta) { /* Nothing */ }
  77                                 for (start = tile; IsRailStationTile(start - delta) && IsCompatibleTrainStationTile(start - delta, tile); start -= delta) { /* Nothing */ }
  78
  79                                 this->tile = start;
  80                                 this->w = TileX(end) - TileX(start) + 1;
  81                                 this->h = TileY(end) - TileY(start) + 1;
  82                                 break;
  83                         }
  84
  85                         case TA_WHOLE:
  86                                 st->GetTileArea(this, Station::IsExpected(st) ? STATION_RAIL : STATION_WAYPOINT);
  87                                 break;
  88                 }
  89         }
  90 };
  91
  92
  93 /**
  94  * Evaluate a tile's position within a station, and return the result in a bit-stuffed format.
  95  * if not centered: .TNLcCpP, if centered: .TNL..CP
  96  * - T = Tile layout number (#GetStationGfx)
  97  * - N = Number of platforms
  98  * - L = Length of platforms
  99  * - C = Current platform number from start, c = from end
 100  * - P = Position along platform from start, p = from end
 101  * .
 102  * if centered, C/P start from the centre and c/p are not available.
 103  * @return Platform information in bit-stuffed format.
 104  */
 105 uint32 GetPlatformInfo(Axis axis, byte tile, int platforms, int length, int x, int y, bool centred)
 106 {
 107         uint32 retval = 0;
 108
 109         if (axis == AXIS_X) {
 110                 Swap(platforms, length);
 111                 Swap(x, y);
 112         }
 113
 114         if (centred) {
 115                 x -= platforms / 2;
 116                 y -= length / 2;
 117                 x = Clamp(x, -8, 7);
 118                 y = Clamp(y, -8, 7);
 119                 SB(retval,  0, 4, y & 0xF);
 120                 SB(retval,  4, 4, x & 0xF);
 121         } else {
 122                 SB(retval,  0, 4, min(15, y));
 123                 SB(retval,  4, 4, min(15, length - y - 1));
 124                 SB(retval,  8, 4, min(15, x));
 125                 SB(retval, 12, 4, min(15, platforms - x - 1));
 126         }
 127         SB(retval, 16, 4, min(15, length));
 128         SB(retval, 20, 4, min(15, platforms));
 129         SB(retval, 24, 4, tile);
 130
 131         return retval;
 132 }
 133
 134
 135 /**
 136  * Find the end of a railway station, from the \a tile, in the direction of \a delta.
 137  * @param tile Start tile.
 138  * @param delta Movement direction.
 139  * @param check_type Stop when the custom station type changes.
 140  * @param check_axis Stop when the station direction changes.
 141  * @return Found end of the railway station.
 142  */
 143 static TileIndex FindRailStationEnd(TileIndex tile, TileIndexDiff delta, bool check_type, bool check_axis)
 144 {
 145         byte orig_type = 0;
 146         Axis orig_axis = AXIS_X;
 147         StationID sid = GetStationIndex(tile);
 148
 149         if (check_type) orig_type = GetCustomStationSpecIndex(tile);
 150         if (check_axis) orig_axis = GetRailStationAxis(tile);
 151
 152         for (;;) {
 153                 TileIndex new_tile = TILE_ADD(tile, delta);
 154
 155                 if (!IsTileType(new_tile, MP_STATION) || GetStationIndex(new_tile) != sid) break;
 156                 if (!HasStationRail(new_tile)) break;
 157                 if (check_type && GetCustomStationSpecIndex(new_tile) != orig_type) break;
 158                 if (check_axis && GetRailStationAxis(new_tile) != orig_axis) break;
 159
 160                 tile = new_tile;
 161         }
 162         return tile;
 163 }
 164
 165
 166 static uint32 GetPlatformInfoHelper(TileIndex tile, bool check_type, bool check_axis, bool centred)
 167 {
 168         int tx = TileX(tile);
 169         int ty = TileY(tile);
 170         int sx = TileX(FindRailStationEnd(tile, TileDiffXY(-1,  0), check_type, check_axis));
 171         int sy = TileY(FindRailStationEnd(tile, TileDiffXY( 0, -1), check_type, check_axis));
 172         int ex = TileX(FindRailStationEnd(tile, TileDiffXY( 1,  0), check_type, check_axis)) + 1;
 173         int ey = TileY(FindRailStationEnd(tile, TileDiffXY( 0,  1), check_type, check_axis)) + 1;
 174
 175         tx -= sx; ex -= sx;
 176         ty -= sy; ey -= sy;
 177
 178         return GetPlatformInfo(GetRailStationAxis(tile), GetStationGfx(tile), ex, ey, tx, ty, centred);
 179 }
 180
 181
 182 static uint32 GetRailContinuationInfo(TileIndex tile)
 183 {
 184         /* Tile offsets and exit dirs for X axis */
 185         static const Direction x_dir[8] = { DIR_SW, DIR_NE, DIR_SE, DIR_NW, DIR_S, DIR_E, DIR_W, DIR_N };
 186         static const DiagDirection x_exits[8] = { DIAGDIR_SW, DIAGDIR_NE, DIAGDIR_SE, DIAGDIR_NW, DIAGDIR_SW, DIAGDIR_NE, DIAGDIR_SW, DIAGDIR_NE };
 187
 188         /* Tile offsets and exit dirs for Y axis */
 189         static const Direction y_dir[8] = { DIR_SE, DIR_NW, DIR_SW, DIR_NE, DIR_S, DIR_W, DIR_E, DIR_N };
 190         static const DiagDirection y_exits[8] = { DIAGDIR_SE, DIAGDIR_NW, DIAGDIR_SW, DIAGDIR_NE, DIAGDIR_SE, DIAGDIR_NW, DIAGDIR_SE, DIAGDIR_NW };
 191
 192         Axis axis = GetRailStationAxis(tile);
 193
 194         /* Choose appropriate lookup table to use */
 195         const Direction *dir = axis == AXIS_X ? x_dir : y_dir;
 196         const DiagDirection *diagdir = axis == AXIS_X ? x_exits : y_exits;
 197
 198         uint32 res = 0;
 199         uint i;
 200
 201         for (i = 0; i < lengthof(x_dir); i++, dir++, diagdir++) {
 202                 TileIndex neighbour_tile = tile + TileOffsByDir(*dir);
 203                 TrackBits trackbits = TrackStatusToTrackBits(GetTileTrackStatus(neighbour_tile, TRANSPORT_RAIL, 0));
 204                 if (trackbits != TRACK_BIT_NONE) {
 205                         /* If there is any track on the tile, set the bit in the second byte */
 206                         SetBit(res, i + 8);
 207
 208                         /* With tunnels and bridges the tile has tracks, but they are not necessarily connected
 209                          * with the next tile because the ramp is not going in the right direction. */
 210                         if (IsTileType(neighbour_tile, MP_TUNNELBRIDGE) && GetTunnelBridgeDirection(neighbour_tile) != *diagdir) {
 211                                 continue;
 212                         }
 213
 214                         /* If any track reaches our exit direction, set the bit in the lower byte */
 215                         if (trackbits & DiagdirReachesTracks(*diagdir)) SetBit(res, i);
 216                 }
 217         }
 218
 219         return res;
 220 }
 221
 222
 223 /* Station Resolver Functions */
 224 /* virtual */ uint32 StationScopeResolver::GetRandomBits() const
 225 {
 226         return (this->st == nullptr ? 0 : this->st->random_bits) | (this->tile == INVALID_TILE ? 0 : GetStationTileRandomBits(this->tile) << 16);
 227 }
 228
 229
 230 /* virtual */ uint32 StationScopeResolver::GetTriggers() const
 231 {
 232         return this->st == nullptr ? 0 : this->st->waiting_triggers;
 233 }
 234
 235
 236 /**
 237  * Station variable cache
 238  * This caches 'expensive' station variable lookups which iterate over
 239  * several tiles that may be called multiple times per Resolve().
 240  */
 241 static struct {
 242         uint32 v40;
 243         uint32 v41;
 244         uint32 v45;
 245         uint32 v46;
 246         uint32 v47;
 247         uint32 v49;
 248         uint8 valid; ///< Bits indicating what variable is valid (for each bit, \c 0 is invalid, \c 1 is valid).
 249 } _svc;
 250
 251 /**
 252  * Get the town scope associated with a station, if it exists.
 253  * On the first call, the town scope is created (if possible).
 254  * @return Town scope, if available.
 255  */
 256 TownScopeResolver *StationResolverObject::GetTown()
 257 {
 258         if (this->town_scope == nullptr) {
 259                 Town *t = nullptr;
 260                 if (this->station_scope.st != nullptr) {
 261                         t = this->station_scope.st->town;
 262                 } else if (this->station_scope.tile != INVALID_TILE) {
 263                         t = ClosestTownFromTile(this->station_scope.tile, UINT_MAX);
 264                 }
 265                 if (t == nullptr) return nullptr;
 266                 this->town_scope = new TownScopeResolver(*this, t, this->station_scope.st == nullptr);
 267         }
 268         return this->town_scope;
 269 }
 270
 271 /* virtual */ uint32 StationScopeResolver::GetVariable(byte variable, uint32 parameter, bool *available) const
 272 {
 273         if (this->st == nullptr) {
 274                 /* Station does not exist, so we're in a purchase list or the land slope check callback. */
 275                 switch (variable) {
 276                         case 0x40:
 277                         case 0x41:
 278                         case 0x46:
 279                         case 0x47:
 280                         case 0x49: return 0x2110000;        // Platforms, tracks & position
 281                         case 0x42: return 0;                // Rail type (XXX Get current type from GUI?)
 282                         case 0x43: return GetCompanyInfo(_current_company); // Station owner
 283                         case 0x44: return 2;                // PBS status
 284                         case 0x67: // Land info of nearby tile
 285                                 if (this->axis != INVALID_AXIS && this->tile != INVALID_TILE) {
 286                                         TileIndex tile = this->tile;
 287                                         if (parameter != 0) tile = GetNearbyTile(parameter, tile, true, this->axis); // only perform if it is required
 288
 289                                         Slope tileh = GetTileSlope(tile);
 290                                         bool swap = (this->axis == AXIS_Y && HasBit(tileh, CORNER_W) != HasBit(tileh, CORNER_E));
 291
 292                                         return GetNearbyTileInformation(tile, this->ro.grffile->grf_version >= 8) ^ (swap ? SLOPE_EW : 0);
 293                                 }
 294                                 break;
 295
 296                         case 0xFA: return Clamp(_date - DAYS_TILL_ORIGINAL_BASE_YEAR, 0, 65535); // Build date, clamped to a 16 bit value
 297                 }
 298
 299                 *available = false;
 300                 return UINT_MAX;
 301         }
 302
 303         switch (variable) {
 304                 /* Calculated station variables */
 305                 case 0x40:
 306                         if (!HasBit(_svc.valid, 0)) { _svc.v40 = GetPlatformInfoHelper(this->tile, false, false, false); SetBit(_svc.valid, 0); }
 307                         return _svc.v40;
 308
 309                 case 0x41:
 310                         if (!HasBit(_svc.valid, 1)) { _svc.v41 = GetPlatformInfoHelper(this->tile, true,  false, false); SetBit(_svc.valid, 1); }
 311                         return _svc.v41;
 312
 313                 case 0x42: return GetTerrainType(this->tile) | (GetReverseRailTypeTranslation(GetRailType(this->tile), this->statspec->grf_prop.grffile) << 8);
 314                 case 0x43: return GetCompanyInfo(this->st->owner); // Station owner
 315                 case 0x44: return HasStationReservation(this->tile) ? 7 : 4; // PBS status
 316                 case 0x45:
 317                         if (!HasBit(_svc.valid, 2)) { _svc.v45 = GetRailContinuationInfo(this->tile); SetBit(_svc.valid, 2); }
 318                         return _svc.v45;
 319
 320                 case 0x46:
 321                         if (!HasBit(_svc.valid, 3)) { _svc.v46 = GetPlatformInfoHelper(this->tile, false, false, true); SetBit(_svc.valid, 3); }
 322                         return _svc.v46;
 323
 324                 case 0x47:
 325                         if (!HasBit(_svc.valid, 4)) { _svc.v47 = GetPlatformInfoHelper(this->tile, true,  false, true); SetBit(_svc.valid, 4); }
 326                         return _svc.v47;
 327
 328                 case 0x49:
 329                         if (!HasBit(_svc.valid, 5)) { _svc.v49 = GetPlatformInfoHelper(this->tile, false, true, false); SetBit(_svc.valid, 5); }
 330                         return _svc.v49;
 331
 332                 case 0x4A: // Animation frame of tile
 333                         return GetAnimationFrame(this->tile);
 334
 335                 /* Variables which use the parameter */
 336                 /* Variables 0x60 to 0x65 and 0x69 are handled separately below */
 337                 case 0x66: { // Animation frame of nearby tile
 338                         TileIndex tile = this->tile;
 339                         if (parameter != 0) tile = GetNearbyTile(parameter, tile);
 340                         return this->st->TileBelongsToRailStation(tile) ? GetAnimationFrame(tile) : UINT_MAX;
 341                 }
 342
 343                 case 0x67: { // Land info of nearby tile
 344                         Axis axis = GetRailStationAxis(this->tile);
 345                         TileIndex tile = this->tile;
 346                         if (parameter != 0) tile = GetNearbyTile(parameter, tile); // only perform if it is required
 347
 348                         Slope tileh = GetTileSlope(tile);
 349                         bool swap = (axis == AXIS_Y && HasBit(tileh, CORNER_W) != HasBit(tileh, CORNER_E));
 350
 351                         return GetNearbyTileInformation(tile, this->ro.grffile->grf_version >= 8) ^ (swap ? SLOPE_EW : 0);
 352                 }
 353
 354                 case 0x68: { // Station info of nearby tiles
 355                         TileIndex nearby_tile = GetNearbyTile(parameter, this->tile);
 356
 357                         if (!HasStationTileRail(nearby_tile)) return 0xFFFFFFFF;
 358
 359                         uint32 grfid = this->st->speclist[GetCustomStationSpecIndex(this->tile)].grfid;
 360                         bool perpendicular = GetRailStationAxis(this->tile) != GetRailStationAxis(nearby_tile);
 361                         bool same_station = this->st->TileBelongsToRailStation(nearby_tile);
 362                         uint32 res = GB(GetStationGfx(nearby_tile), 1, 2) << 12 | !!perpendicular << 11 | !!same_station << 10;
 363
 364                         if (IsCustomStationSpecIndex(nearby_tile)) {
 365                                 const StationSpecList ssl = BaseStation::GetByTile(nearby_tile)->speclist[GetCustomStationSpecIndex(nearby_tile)];
 366                                 res |= 1 << (ssl.grfid != grfid ? 9 : 8) | ssl.localidx;
 367                         }
 368                         return res;
 369                 }
 370
 371                 case 0x6A: { // GRFID of nearby station tiles
 372                         TileIndex nearby_tile = GetNearbyTile(parameter, this->tile);
 373
 374                         if (!HasStationTileRail(nearby_tile)) return 0xFFFFFFFF;
 375                         if (!IsCustomStationSpecIndex(nearby_tile)) return 0;
 376
 377                         const StationSpecList ssl = BaseStation::GetByTile(nearby_tile)->speclist[GetCustomStationSpecIndex(nearby_tile)];
 378                         return ssl.grfid;
 379                 }
 380
 381                 /* General station variables */
 382                 case 0x82: return 50;
 383                 case 0x84: return this->st->string_id;
 384                 case 0x86: return 0;
 385                 case 0xF0: return this->st->facilities;
 386                 case 0xFA: return Clamp(this->st->build_date - DAYS_TILL_ORIGINAL_BASE_YEAR, 0, 65535);
 387         }
 388
 389         return this->st->GetNewGRFVariable(this->ro, variable, parameter, available);
 390 }
 391
 392 uint32 Station::GetNewGRFVariable(const ResolverObject &object, byte variable, byte parameter, bool *available) const
 393 {
 394         switch (variable) {
 395                 case 0x48: { // Accepted cargo types
 396                         CargoID cargo_type;
 397                         uint32 value = 0;
 398
 399                         for (cargo_type = 0; cargo_type < NUM_CARGO; cargo_type++) {
 400                                 if (HasBit(this->goods[cargo_type].status, GoodsEntry::GES_ACCEPTANCE)) SetBit(value, cargo_type);
 401                         }
 402                         return value;
 403                 }
 404
 405                 case 0x8A: return this->had_vehicle_of_type;
 406                 case 0xF1: return (this->airport.tile != INVALID_TILE) ? this->airport.GetSpec()->ttd_airport_type : ATP_TTDP_LARGE;
 407                 case 0xF2: return (this->truck_stops != nullptr) ? this->truck_stops->status : 0;
 408                 case 0xF3: return (this->bus_stops != nullptr)   ? this->bus_stops->status   : 0;
 409                 case 0xF6: return this->airport.flags;
 410                 case 0xF7: return GB(this->airport.flags, 8, 8);
 411         }
 412
 413         /* Handle cargo variables with parameter, 0x60 to 0x65 and 0x69 */
 414         if ((variable >= 0x60 && variable <= 0x65) || variable == 0x69) {
 415                 CargoID c = GetCargoTranslation(parameter, object.grffile);
 416
 417                 if (c == CT_INVALID) {
 418                         switch (variable) {
 419                                 case 0x62: return 0xFFFFFFFF;
 420                                 case 0x64: return 0xFF00;
 421                                 default:   return 0;
 422                         }
 423                 }
 424                 const GoodsEntry *ge = &this->goods[c];
 425
 426                 switch (variable) {
 427                         case 0x60: return min(ge->cargo.TotalCount(), 4095);
 428                         case 0x61: return ge->HasVehicleEverTriedLoading() ? ge->time_since_pickup : 0;
 429                         case 0x62: return ge->HasRating() ? ge->rating : 0xFFFFFFFF;
 430                         case 0x63: return ge->cargo.DaysInTransit();
 431                         case 0x64: return ge->HasVehicleEverTriedLoading() ? ge->last_speed | (ge->last_age << 8) : 0xFF00;
 432                         case 0x65: return GB(ge->status, GoodsEntry::GES_ACCEPTANCE, 1) << 3;
 433                         case 0x69: {
 434                                 assert_compile((int)GoodsEntry::GES_EVER_ACCEPTED + 1 == (int)GoodsEntry::GES_LAST_MONTH);
 435                                 assert_compile((int)GoodsEntry::GES_EVER_ACCEPTED + 2 == (int)GoodsEntry::GES_CURRENT_MONTH);
 436                                 assert_compile((int)GoodsEntry::GES_EVER_ACCEPTED + 3 == (int)GoodsEntry::GES_ACCEPTED_BIGTICK);
 437                                 return GB(ge->status, GoodsEntry::GES_EVER_ACCEPTED, 4);
 438                         }
 439                 }
 440         }
 441
 442         /* Handle cargo variables (deprecated) */
 443         if (variable >= 0x8C && variable <= 0xEC) {
 444                 const GoodsEntry *g = &this->goods[GB(variable - 0x8C, 3, 4)];
 445                 switch (GB(variable - 0x8C, 0, 3)) {
 446                         case 0: return g->cargo.TotalCount();
 447                         case 1: return GB(min(g->cargo.TotalCount(), 4095), 0, 4) | (GB(g->status, GoodsEntry::GES_ACCEPTANCE, 1) << 7);
 448                         case 2: return g->time_since_pickup;
 449                         case 3: return g->rating;
 450                         case 4: return g->cargo.Source();
 451                         case 5: return g->cargo.DaysInTransit();
 452                         case 6: return g->last_speed;
 453                         case 7: return g->last_age;
 454                 }
 455         }
 456
 457         DEBUG(grf, 1, "Unhandled station variable 0x%X", variable);
 458
 459         *available = false;
 460         return UINT_MAX;
 461 }
 462
 463 uint32 Waypoint::GetNewGRFVariable(const ResolverObject &object, byte variable, byte parameter, bool *available) const
 464 {
 465         switch (variable) {
 466                 case 0x48: return 0; // Accepted cargo types
 467                 case 0x8A: return HVOT_WAYPOINT;
 468                 case 0xF1: return 0; // airport type
 469                 case 0xF2: return 0; // truck stop status
 470                 case 0xF3: return 0; // bus stop status
 471                 case 0xF6: return 0; // airport flags
 472                 case 0xF7: return 0; // airport flags cont.
 473         }
 474
 475         /* Handle cargo variables with parameter, 0x60 to 0x65 */
 476         if (variable >= 0x60 && variable <= 0x65) {
 477                 return 0;
 478         }
 479
 480         /* Handle cargo variables (deprecated) */
 481         if (variable >= 0x8C && variable <= 0xEC) {
 482                 switch (GB(variable - 0x8C, 0, 3)) {
 483                         case 3: return INITIAL_STATION_RATING;
 484                         case 4: return INVALID_STATION;
 485                         default: return 0;
 486                 }
 487         }
 488
 489         DEBUG(grf, 1, "Unhandled station variable 0x%X", variable);
 490
 491         *available = false;
 492         return UINT_MAX;
 493 }
 494
 495 /* virtual */ const SpriteGroup *StationResolverObject::ResolveReal(const RealSpriteGroup *group) const
 496 {
 497         if (this->station_scope.st == nullptr || this->station_scope.statspec->cls_id == STAT_CLASS_WAYP) {
 498                 return group->loading[0];
 499         }
 500
 501         uint cargo = 0;
 502         const Station *st = Station::From(this->station_scope.st);
 503
 504         switch (this->station_scope.cargo_type) {
 505                 case CT_INVALID:
 506                 case CT_DEFAULT_NA:
 507                 case CT_PURCHASE:
 508                         cargo = 0;
 509                         break;
 510
 511                 case CT_DEFAULT:
 512                         for (CargoID cargo_type = 0; cargo_type < NUM_CARGO; cargo_type++) {
 513                                 cargo += st->goods[cargo_type].cargo.TotalCount();
 514                         }
 515                         break;
 516
 517                 default:
 518                         cargo = st->goods[this->station_scope.cargo_type].cargo.TotalCount();
 519                         break;
 520         }
 521
 522         if (HasBit(this->station_scope.statspec->flags, SSF_DIV_BY_STATION_SIZE)) cargo /= (st->train_station.w + st->train_station.h);
 523         cargo = min(0xfff, cargo);
 524
 525         if (cargo > this->station_scope.statspec->cargo_threshold) {
 526                 if (group->num_loading > 0) {
 527                         uint set = ((cargo - this->station_scope.statspec->cargo_threshold) * group->num_loading) / (4096 - this->station_scope.statspec->cargo_threshold);
 528                         return group->loading[set];
 529                 }
 530         } else {
 531                 if (group->num_loaded > 0) {
 532                         uint set = (cargo * group->num_loaded) / (this->station_scope.statspec->cargo_threshold + 1);
 533                         return group->loaded[set];
 534                 }
 535         }
 536
 537         return group->loading[0];
 538 }
 539
 540 GrfSpecFeature StationResolverObject::GetFeature() const
 541 {
 542         return GSF_STATIONS;
 543 }
 544
 545 uint32 StationResolverObject::GetDebugID() const
 546 {
 547         return this->station_scope.statspec->grf_prop.local_id;
 548 }
 549
 550 /**
 551  * Resolver for stations.
 552  * @param statspec Station (type) specification.
 553  * @param st Instance of the station.
 554  * @param tile %Tile of the station.
 555  * @param callback Callback ID.
 556  * @param callback_param1 First parameter (var 10) of the callback.
 557  * @param callback_param2 Second parameter (var 18) of the callback.
 558  */
 559 StationResolverObject::StationResolverObject(const StationSpec *statspec, BaseStation *st, TileIndex tile,
 560                 CallbackID callback, uint32 callback_param1, uint32 callback_param2)
 561         : ResolverObject(statspec->grf_prop.grffile, callback, callback_param1, callback_param2),
 562         station_scope(*this, statspec, st, tile), town_scope(nullptr)
 563 {
 564         /* Invalidate all cached vars */
 565         _svc.valid = 0;
 566
 567         CargoID ctype = CT_DEFAULT_NA;
 568
 569         if (this->station_scope.st == nullptr) {
 570                 /* No station, so we are in a purchase list */
 571                 ctype = CT_PURCHASE;
 572         } else if (Station::IsExpected(this->station_scope.st)) {
 573                 const Station *st = Station::From(this->station_scope.st);
 574                 /* Pick the first cargo that we have waiting */
 575                 const CargoSpec *cs;
 576                 FOR_ALL_CARGOSPECS(cs) {
 577                         if (this->station_scope.statspec->grf_prop.spritegroup[cs->Index()] != nullptr &&
 578                                         st->goods[cs->Index()].cargo.TotalCount() > 0) {
 579                                 ctype = cs->Index();
 580                                 break;
 581                         }
 582                 }
 583         }
 584
 585         if (this->station_scope.statspec->grf_prop.spritegroup[ctype] == nullptr) {
 586                 ctype = CT_DEFAULT;
 587         }
 588
 589         /* Remember the cargo type we've picked */
 590         this->station_scope.cargo_type = ctype;
 591         this->root_spritegroup = this->station_scope.statspec->grf_prop.spritegroup[this->station_scope.cargo_type];
 592 }
 593
 594 StationResolverObject::~StationResolverObject()
 595 {
 596         delete this->town_scope;
 597 }
 598
 599 /**
 600  * Resolve sprites for drawing a station tile.
 601  * @param statspec Station spec
 602  * @param st Station (nullptr in GUI)
 603  * @param tile Station tile being drawn (INVALID_TILE in GUI)
 604  * @param var10 Value to put in variable 10; normally 0; 1 when resolving the groundsprite and SSF_SEPARATE_GROUND is set.
 605  * @return First sprite of the Action 1 spriteset to use, minus an offset of 0x42D to accommodate for weird NewGRF specs.
 606  */
 607 SpriteID GetCustomStationRelocation(const StationSpec *statspec, BaseStation *st, TileIndex tile, uint32 var10)
 608 {
 609         StationResolverObject object(statspec, st, tile, CBID_NO_CALLBACK, var10);
 610         const SpriteGroup *group = object.Resolve();
 611         if (group == nullptr || group->type != SGT_RESULT) return 0;
 612         return group->GetResult() - 0x42D;
 613 }
 614
 615 /**
 616  * Resolve the sprites for custom station foundations.
 617  * @param statspec Station spec
 618  * @param st Station
 619  * @param tile Station tile being drawn
 620  * @param layout Spritelayout as returned by previous callback
 621  * @param edge_info Information about northern tile edges; whether they need foundations or merge into adjacent tile's foundations.
 622  * @return First sprite of a set of foundation sprites for various slopes, or 0 if default foundations shall be drawn.
 623  */
 624 SpriteID GetCustomStationFoundationRelocation(const StationSpec *statspec, BaseStation *st, TileIndex tile, uint layout, uint edge_info)
 625 {
 626         /* callback_param1 == 2 means  we are resolving the foundation sprites. */
 627         StationResolverObject object(statspec, st, tile, CBID_NO_CALLBACK, 2, layout | (edge_info << 16));
 628
 629         const SpriteGroup *group = object.Resolve();
 630         if (group == nullptr || group->type != SGT_RESULT) return 0;
 631
 632         /* Note: SpriteGroup::Resolve zeroes all registers, so register 0x100 is initialised to 0. (compatibility) */
 633         return group->GetResult() + GetRegister(0x100);
 634 }
 635
 636
 637 uint16 GetStationCallback(CallbackID callback, uint32 param1, uint32 param2, const StationSpec *statspec, BaseStation *st, TileIndex tile)
 638 {
 639         StationResolverObject object(statspec, st, tile, callback, param1, param2);
 640         return object.ResolveCallback();
 641 }
 642
 643 /**
 644  * Check the slope of a tile of a new station.
 645  * @param north_tile Norther tile of the station rect.
 646  * @param cur_tile Tile to check.
 647  * @param statspec Station spec.
 648  * @param axis Axis of the new station.
 649  * @param plat_len Platform length.
 650  * @param numtracks Number of platforms.
 651  * @return Succeeded or failed command.
 652  */
 653 CommandCost PerformStationTileSlopeCheck(TileIndex north_tile, TileIndex cur_tile, const StationSpec *statspec, Axis axis, byte plat_len, byte numtracks)
 654 {
 655         TileIndexDiff diff = cur_tile - north_tile;
 656         Slope slope = GetTileSlope(cur_tile);
 657
 658         StationResolverObject object(statspec, nullptr, cur_tile, CBID_STATION_LAND_SLOPE_CHECK,
 659                         (slope << 4) | (slope ^ (axis == AXIS_Y && HasBit(slope, CORNER_W) != HasBit(slope, CORNER_E) ? SLOPE_EW : 0)),
 660                         (numtracks << 24) | (plat_len << 16) | (axis == AXIS_Y ? TileX(diff) << 8 | TileY(diff) : TileY(diff) << 8 | TileX(diff)));
 661         object.station_scope.axis = axis;
 662
 663         uint16 cb_res = object.ResolveCallback();
 664
 665         /* Failed callback means success. */
 666         if (cb_res == CALLBACK_FAILED) return CommandCost();
 667
 668         /* The meaning of bit 10 is inverted for a grf version < 8. */
 669         if (statspec->grf_prop.grffile->grf_version < 8) ToggleBit(cb_res, 10);
 670         return GetErrorMessageFromLocationCallbackResult(cb_res, statspec->grf_prop.grffile, STR_ERROR_LAND_SLOPED_IN_WRONG_DIRECTION);
 671 }
 672
 673
 674 /**
 675  * Allocate a StationSpec to a Station. This is called once per build operation.
 676  * @param statspec StationSpec to allocate.
 677  * @param st Station to allocate it to.
 678  * @param exec Whether to actually allocate the spec.
 679  * @return Index within the Station's spec list, or -1 if the allocation failed.
 680  */
 681 int AllocateSpecToStation(const StationSpec *statspec, BaseStation *st, bool exec)
 682 {
 683         uint i;
 684
 685         if (statspec == nullptr || st == nullptr) return 0;
 686
 687         for (i = 1; i < st->num_specs && i < NUM_STATIONSSPECS_PER_STATION; i++) {
 688                 if (st->speclist[i].spec == nullptr && st->speclist[i].grfid == 0) break;
 689         }
 690
 691         if (i == NUM_STATIONSSPECS_PER_STATION) {
 692                 /* As final effort when the spec list is already full...
 693                  * try to find the same spec and return that one. This might
 694                  * result in slightly "wrong" (as per specs) looking stations,
 695                  * but it's fairly unlikely that one reaches the limit anyways.
 696                  */
 697                 for (i = 1; i < st->num_specs && i < NUM_STATIONSSPECS_PER_STATION; i++) {
 698                         if (st->speclist[i].spec == statspec) return i;
 699                 }
 700
 701                 return -1;
 702         }
 703
 704         if (exec) {
 705                 if (i >= st->num_specs) {
 706                         st->num_specs = i + 1;
 707                         st->speclist = ReallocT(st->speclist, st->num_specs);
 708
 709                         if (st->num_specs == 2) {
 710                                 /* Initial allocation */
 711                                 st->speclist[0].spec     = nullptr;
 712                                 st->speclist[0].grfid    = 0;
 713                                 st->speclist[0].localidx = 0;
 714                         }
 715                 }
 716
 717                 st->speclist[i].spec     = statspec;
 718                 st->speclist[i].grfid    = statspec->grf_prop.grffile->grfid;
 719                 st->speclist[i].localidx = statspec->grf_prop.local_id;
 720
 721                 StationUpdateCachedTriggers(st);
 722         }
 723
 724         return i;
 725 }
 726
 727
 728 /**
 729  * Deallocate a StationSpec from a Station. Called when removing a single station tile.
 730  * @param st Station to work with.
 731  * @param specindex Index of the custom station within the Station's spec list.
 732  * @return Indicates whether the StationSpec was deallocated.
 733  */
 734 void DeallocateSpecFromStation(BaseStation *st, byte specindex)
 735 {
 736         /* specindex of 0 (default) is never freeable */
 737         if (specindex == 0) return;
 738
 739         ETileArea area = ETileArea(st, INVALID_TILE, TA_WHOLE);
 740         /* Check all tiles over the station to check if the specindex is still in use */
 741         TILE_AREA_LOOP(tile, area) {
 742                 if (st->TileBelongsToRailStation(tile) && GetCustomStationSpecIndex(tile) == specindex) {
 743                         return;
 744                 }
 745         }
 746
 747         /* This specindex is no longer in use, so deallocate it */
 748         st->speclist[specindex].spec     = nullptr;
 749         st->speclist[specindex].grfid    = 0;
 750         st->speclist[specindex].localidx = 0;
 751
 752         /* If this was the highest spec index, reallocate */
 753         if (specindex == st->num_specs - 1) {
 754                 for (; st->speclist[st->num_specs - 1].grfid == 0 && st->num_specs > 1; st->num_specs--) {}
 755
 756                 if (st->num_specs > 1) {
 757                         st->speclist = ReallocT(st->speclist, st->num_specs);
 758                 } else {
 759                         free(st->speclist);
 760                         st->num_specs = 0;
 761                         st->speclist  = nullptr;
 762                         st->cached_anim_triggers = 0;
 763                         st->cached_cargo_triggers = 0;
 764                         return;
 765                 }
 766         }
 767
 768         StationUpdateCachedTriggers(st);
 769 }
 770
 771 /**
 772  * Draw representation of a station tile for GUI purposes.
 773  * @param x Position x of image.
 774  * @param y Position y of image.
 775  * @param axis Axis.
 776  * @param railtype Rail type.
 777  * @param sclass, station Type of station.
 778  * @param station station ID
 779  * @return True if the tile was drawn (allows for fallback to default graphic)
 780  */
 781 bool DrawStationTile(int x, int y, RailType railtype, Axis axis, StationClassID sclass, uint station)
 782 {
 783         const DrawTileSprites *sprites = nullptr;
 784         const RailtypeInfo *rti = GetRailTypeInfo(railtype);
 785         PaletteID palette = COMPANY_SPRITE_COLOUR(_local_company);
 786         uint tile = 2;
 787
 788         const StationSpec *statspec = StationClass::Get(sclass)->GetSpec(station);
 789         if (statspec == nullptr) return false;
 790
 791         if (HasBit(statspec->callback_mask, CBM_STATION_SPRITE_LAYOUT)) {
 792                 uint16 callback = GetStationCallback(CBID_STATION_SPRITE_LAYOUT, 0x2110000, 0, statspec, nullptr, INVALID_TILE);
 793                 if (callback != CALLBACK_FAILED) tile = callback;
 794         }
 795
 796         uint32 total_offset = rti->GetRailtypeSpriteOffset();
 797         uint32 relocation = 0;
 798         uint32 ground_relocation = 0;
 799         const NewGRFSpriteLayout *layout = nullptr;
 800         DrawTileSprites tmp_rail_layout;
 801
 802         if (statspec->renderdata == nullptr) {
 803                 sprites = GetStationTileLayout(STATION_RAIL, tile + axis);
 804         } else {
 805                 layout = &statspec->renderdata[(tile < statspec->tiles) ? tile + axis : (uint)axis];
 806                 if (!layout->NeedsPreprocessing()) {
 807                         sprites = layout;
 808                         layout = nullptr;
 809                 }
 810         }
 811
 812         if (layout != nullptr) {
 813                 /* Sprite layout which needs preprocessing */
 814                 bool separate_ground = HasBit(statspec->flags, SSF_SEPARATE_GROUND);
 815                 uint32 var10_values = layout->PrepareLayout(total_offset, rti->fallback_railtype, 0, 0, separate_ground);
 816                 uint8 var10;
 817                 FOR_EACH_SET_BIT(var10, var10_values) {
 818                         uint32 var10_relocation = GetCustomStationRelocation(statspec, nullptr, INVALID_TILE, var10);
 819                         layout->ProcessRegisters(var10, var10_relocation, separate_ground);
 820                 }
 821
 822                 tmp_rail_layout.seq = layout->GetLayout(&tmp_rail_layout.ground);
 823                 sprites = &tmp_rail_layout;
 824                 total_offset = 0;
 825         } else {
 826                 /* Simple sprite layout */
 827                 ground_relocation = relocation = GetCustomStationRelocation(statspec, nullptr, INVALID_TILE, 0);
 828                 if (HasBit(sprites->ground.sprite, SPRITE_MODIFIER_CUSTOM_SPRITE)) {
 829                         ground_relocation = GetCustomStationRelocation(statspec, nullptr, INVALID_TILE, 1);
 830                 }
 831                 ground_relocation += rti->fallback_railtype;
 832         }
 833
 834         SpriteID image = sprites->ground.sprite;
 835         PaletteID pal = sprites->ground.pal;
 836         RailTrackOffset overlay_offset;
 837         if (rti->UsesOverlay() && SplitGroundSpriteForOverlay(nullptr, &image, &overlay_offset)) {
 838                 SpriteID ground = GetCustomRailSprite(rti, INVALID_TILE, RTSG_GROUND);
 839                 DrawSprite(image, PAL_NONE, x, y);
 840                 DrawSprite(ground + overlay_offset, PAL_NONE, x, y);
 841         } else {
 842                 image += HasBit(image, SPRITE_MODIFIER_CUSTOM_SPRITE) ? ground_relocation : total_offset;
 843                 if (HasBit(pal, SPRITE_MODIFIER_CUSTOM_SPRITE)) pal += ground_relocation;
 844                 DrawSprite(image, GroundSpritePaletteTransform(image, pal, palette), x, y);
 845         }
 846
 847         DrawRailTileSeqInGUI(x, y, sprites, total_offset, relocation, palette);
 848
 849         return true;
 850 }
 851
 852
 853 const StationSpec *GetStationSpec(TileIndex t)
 854 {
 855         if (!IsCustomStationSpecIndex(t)) return nullptr;
 856
 857         const BaseStation *st = BaseStation::GetByTile(t);
 858         uint specindex = GetCustomStationSpecIndex(t);
 859         return specindex < st->num_specs ? st->speclist[specindex].spec : nullptr;
 860 }
 861
 862
 863 /**
 864  * Check whether a rail station tile is NOT traversable.
 865  * @param tile %Tile to test.
 866  * @return Station tile is blocked.
 867  * @note This could be cached (during build) in the map array to save on all the dereferencing.
 868  */
 869 bool IsStationTileBlocked(TileIndex tile)
 870 {
 871         const StationSpec *statspec = GetStationSpec(tile);
 872
 873         return statspec != nullptr && HasBit(statspec->blocked, GetStationGfx(tile));
 874 }
 875
 876 /**
 877  * Check if a rail station tile shall have pylons when electrified.
 878  * @param tile %Tile to test.
 879  * @return Tile shall have pylons.
 880  * @note This could be cached (during build) in the map array to save on all the dereferencing.
 881  */
 882 bool CanStationTileHavePylons(TileIndex tile)
 883 {
 884         const StationSpec *statspec = GetStationSpec(tile);
 885         uint gfx = GetStationGfx(tile);
 886         /* Default stations do not draw pylons under roofs (gfx >= 4) */
 887         return statspec != nullptr ? HasBit(statspec->pylons, gfx) : gfx < 4;
 888 }
 889
 890 /**
 891  * Check if a rail station tile shall have wires when electrified.
 892  * @param tile %Tile to test.
 893  * @return Tile shall have wires.
 894  * @note This could be cached (during build) in the map array to save on all the dereferencing.
 895  */
 896 bool CanStationTileHaveWires(TileIndex tile)
 897 {
 898         const StationSpec *statspec = GetStationSpec(tile);
 899         return statspec == nullptr || !HasBit(statspec->wires, GetStationGfx(tile));
 900 }
 901
 902 /** Wrapper for animation control, see GetStationCallback. */
 903 uint16 GetAnimStationCallback(CallbackID callback, uint32 param1, uint32 param2, const StationSpec *statspec, BaseStation *st, TileIndex tile, int extra_data)
 904 {
 905         return GetStationCallback(callback, param1, param2, statspec, st, tile);
 906 }
 907
 908 /** Helper class for animation control. */
 909 struct StationAnimationBase : public AnimationBase<StationAnimationBase, StationSpec, BaseStation, int, GetAnimStationCallback> {
 910         static const CallbackID cb_animation_speed      = CBID_STATION_ANIMATION_SPEED;
 911         static const CallbackID cb_animation_next_frame = CBID_STATION_ANIM_NEXT_FRAME;
 912
 913         static const StationCallbackMask cbm_animation_speed      = CBM_STATION_ANIMATION_SPEED;
 914         static const StationCallbackMask cbm_animation_next_frame = CBM_STATION_ANIMATION_NEXT_FRAME;
 915 };
 916
 917 void AnimateStationTile(TileIndex tile)
 918 {
 919         const StationSpec *ss = GetStationSpec(tile);
 920         if (ss == nullptr) return;
 921
 922         StationAnimationBase::AnimateTile(ss, BaseStation::GetByTile(tile), tile, HasBit(ss->flags, SSF_CB141_RANDOM_BITS));
 923 }
 924
 925 void TriggerStationAnimation(BaseStation *st, TileIndex tile, StationAnimationTrigger trigger, CargoID cargo_type)
 926 {
 927         /* List of coverage areas for each animation trigger */
 928         static const TriggerArea tas[] = {
 929                 TA_TILE, TA_WHOLE, TA_WHOLE, TA_PLATFORM, TA_PLATFORM, TA_PLATFORM, TA_WHOLE
 930         };
 931
 932         /* Get Station if it wasn't supplied */
 933         if (st == nullptr) st = BaseStation::GetByTile(tile);
 934
 935         /* Check the cached animation trigger bitmask to see if we need
 936          * to bother with any further processing. */
 937         if (!HasBit(st->cached_anim_triggers, trigger)) return;
 938
 939         uint16 random_bits = Random();
 940         ETileArea area = ETileArea(st, tile, tas[trigger]);
 941
 942         /* Check all tiles over the station to check if the specindex is still in use */
 943         TILE_AREA_LOOP(tile, area) {
 944                 if (st->TileBelongsToRailStation(tile)) {
 945                         const StationSpec *ss = GetStationSpec(tile);
 946                         if (ss != nullptr && HasBit(ss->animation.triggers, trigger)) {
 947                                 CargoID cargo;
 948                                 if (cargo_type == CT_INVALID) {
 949                                         cargo = CT_INVALID;
 950                                 } else {
 951                                         cargo = ss->grf_prop.grffile->cargo_map[cargo_type];
 952                                 }
 953                                 StationAnimationBase::ChangeAnimationFrame(CBID_STATION_ANIM_START_STOP, ss, st, tile, (random_bits << 16) | Random(), (uint8)trigger | (cargo << 8));
 954                         }
 955                 }
 956         }
 957 }
 958
 959 /**
 960  * Trigger station randomisation
 961  * @param st station being triggered
 962  * @param tile specific tile of platform to trigger
 963  * @param trigger trigger type
 964  * @param cargo_type cargo type causing trigger
 965  */
 966 void TriggerStationRandomisation(Station *st, TileIndex tile, StationRandomTrigger trigger, CargoID cargo_type)
 967 {
 968         /* List of coverage areas for each animation trigger */
 969         static const TriggerArea tas[] = {
 970                 TA_WHOLE, TA_WHOLE, TA_PLATFORM, TA_PLATFORM, TA_PLATFORM, TA_PLATFORM
 971         };
 972
 973         /* Get Station if it wasn't supplied */
 974         if (st == nullptr) st = Station::GetByTile(tile);
 975
 976         /* Check the cached cargo trigger bitmask to see if we need
 977          * to bother with any further processing. */
 978         if (st->cached_cargo_triggers == 0) return;
 979         if (cargo_type != CT_INVALID && !HasBit(st->cached_cargo_triggers, cargo_type)) return;
 980
 981         uint32 whole_reseed = 0;
 982         ETileArea area = ETileArea(st, tile, tas[trigger]);
 983
 984         CargoTypes empty_mask = 0;
 985         if (trigger == SRT_CARGO_TAKEN) {
 986                 /* Create a bitmask of completely empty cargo types to be matched */
 987                 for (CargoID i = 0; i < NUM_CARGO; i++) {
 988                         if (st->goods[i].cargo.TotalCount() == 0) {
 989                                 SetBit(empty_mask, i);
 990                         }
 991                 }
 992         }
 993
 994         /* Store triggers now for var 5F */
 995         SetBit(st->waiting_triggers, trigger);
 996         uint32 used_triggers = 0;
 997
 998         /* Check all tiles over the station to check if the specindex is still in use */
 999         TILE_AREA_LOOP(tile, area) {
1000                 if (st->TileBelongsToRailStation(tile)) {
1001                         const StationSpec *ss = GetStationSpec(tile);
1002                         if (ss == nullptr) continue;
1003
1004                         /* Cargo taken "will only be triggered if all of those
1005                          * cargo types have no more cargo waiting." */
1006                         if (trigger == SRT_CARGO_TAKEN) {
1007                                 if ((ss->cargo_triggers & ~empty_mask) != 0) continue;
1008                         }
1009
1010                         if (cargo_type == CT_INVALID || HasBit(ss->cargo_triggers, cargo_type)) {
1011                                 StationResolverObject object(ss, st, tile, CBID_RANDOM_TRIGGER, 0);
1012                                 object.waiting_triggers = st->waiting_triggers;
1013
1014                                 const SpriteGroup *group = object.Resolve();
1015                                 if (group == nullptr) continue;
1016
1017                                 used_triggers |= object.used_triggers;
1018
1019                                 uint32 reseed = object.GetReseedSum();
1020                                 if (reseed != 0) {
1021                                         whole_reseed |= reseed;
1022                                         reseed >>= 16;
1023
1024                                         /* Set individual tile random bits */
1025                                         uint8 random_bits = GetStationTileRandomBits(tile);
1026                                         random_bits &= ~reseed;
1027                                         random_bits |= Random() & reseed;
1028                                         SetStationTileRandomBits(tile, random_bits);
1029
1030                                         MarkTileDirtyByTile(tile);
1031                                 }
1032                         }
1033                 }
1034         }
1035
1036         /* Update whole station random bits */
1037         st->waiting_triggers &= ~used_triggers;
1038         if ((whole_reseed & 0xFFFF) != 0) {
1039                 st->random_bits &= ~whole_reseed;
1040                 st->random_bits |= Random() & whole_reseed;
1041         }
1042 }
1043
1044 /**
1045  * Update the cached animation trigger bitmask for a station.
1046  * @param st Station to update.
1047  */
1048 void StationUpdateCachedTriggers(BaseStation *st)
1049 {
1050         st->cached_anim_triggers = 0;
1051         st->cached_cargo_triggers = 0;
1052
1053         /* Combine animation trigger bitmask for all station specs
1054          * of this station. */
1055         for (uint i = 0; i < st->num_specs; i++) {
1056                 const StationSpec *ss = st->speclist[i].spec;
1057                 if (ss != nullptr) {
1058                         st->cached_anim_triggers |= ss->animation.triggers;
1059                         st->cached_cargo_triggers |= ss->cargo_triggers;
1060                 }
1061         }
1062 }
1063