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 #include "timer/timer_game_calendar.h"
  27
  28 #include "safeguards.h"
  29
  30
  31 template <typename Tspec, typename Tid, Tid Tmax>
  32 /* static */ void NewGRFClass<Tspec, Tid, Tmax>::InsertDefaults()
  33 {
  34         /* Set up initial data */
  35         StationClass::Get(StationClass::Allocate('DFLT'))->name = STR_STATION_CLASS_DFLT;
  36         StationClass::Get(StationClass::Allocate('DFLT'))->Insert(nullptr);
  37         StationClass::Get(StationClass::Allocate('WAYP'))->name = STR_STATION_CLASS_WAYP;
  38         StationClass::Get(StationClass::Allocate('WAYP'))->Insert(nullptr);
  39 }
  40
  41 template <typename Tspec, typename Tid, Tid Tmax>
  42 bool NewGRFClass<Tspec, Tid, Tmax>::IsUIAvailable(uint) const
  43 {
  44         return true;
  45 }
  46
  47 INSTANTIATE_NEWGRF_CLASS_METHODS(StationClass, StationSpec, StationClassID, STAT_CLASS_MAX)
  48
  49 static const uint NUM_STATIONSSPECS_PER_STATION = 255; ///< Maximum number of parts per station.
  50
  51 enum TriggerArea {
  52         TA_TILE,
  53         TA_PLATFORM,
  54         TA_WHOLE,
  55 };
  56
  57 struct ETileArea : TileArea {
  58         ETileArea(const BaseStation *st, TileIndex tile, TriggerArea ta)
  59         {
  60                 switch (ta) {
  61                         default: NOT_REACHED();
  62
  63                         case TA_TILE:
  64                                 this->tile = tile;
  65                                 this->w    = 1;
  66                                 this->h    = 1;
  67                                 break;
  68
  69                         case TA_PLATFORM: {
  70                                 TileIndex start, end;
  71                                 Axis axis = GetRailStationAxis(tile);
  72                                 TileIndexDiff delta = TileOffsByDiagDir(AxisToDiagDir(axis));
  73
  74                                 for (end = tile; IsRailStationTile(end + delta) && IsCompatibleTrainStationTile(end + delta, tile); end += delta) { /* Nothing */ }
  75                                 for (start = tile; IsRailStationTile(start - delta) && IsCompatibleTrainStationTile(start - delta, tile); start -= delta) { /* Nothing */ }
  76
  77                                 this->tile = start;
  78                                 this->w = TileX(end) - TileX(start) + 1;
  79                                 this->h = TileY(end) - TileY(start) + 1;
  80                                 break;
  81                         }
  82
  83                         case TA_WHOLE:
  84                                 st->GetTileArea(this, Station::IsExpected(st) ? STATION_RAIL : STATION_WAYPOINT);
  85                                 break;
  86                 }
  87         }
  88 };
  89
  90
  91 /**
  92  * Evaluate a tile's position within a station, and return the result in a bit-stuffed format.
  93  * if not centered: .TNLcCpP, if centered: .TNL..CP
  94  * - T = Tile layout number (#GetStationGfx)
  95  * - N = Number of platforms
  96  * - L = Length of platforms
  97  * - C = Current platform number from start, c = from end
  98  * - P = Position along platform from start, p = from end
  99  * .
 100  * if centered, C/P start from the centre and c/p are not available.
 101  * @return Platform information in bit-stuffed format.
 102  */
 103 uint32_t GetPlatformInfo(Axis axis, byte tile, int platforms, int length, int x, int y, bool centred)
 104 {
 105         uint32_t retval = 0;
 106
 107         if (axis == AXIS_X) {
 108                 Swap(platforms, length);
 109                 Swap(x, y);
 110         }
 111
 112         if (centred) {
 113                 x -= platforms / 2;
 114                 y -= length / 2;
 115                 x = Clamp(x, -8, 7);
 116                 y = Clamp(y, -8, 7);
 117                 SB(retval,  0, 4, y & 0xF);
 118                 SB(retval,  4, 4, x & 0xF);
 119         } else {
 120                 SB(retval,  0, 4, std::min(15, y));
 121                 SB(retval,  4, 4, std::min(15, length - y - 1));
 122                 SB(retval,  8, 4, std::min(15, x));
 123                 SB(retval, 12, 4, std::min(15, platforms - x - 1));
 124         }
 125         SB(retval, 16, 4, std::min(15, length));
 126         SB(retval, 20, 4, std::min(15, platforms));
 127         SB(retval, 24, 4, tile);
 128
 129         return retval;
 130 }
 131
 132
 133 /**
 134  * Find the end of a railway station, from the \a tile, in the direction of \a delta.
 135  * @param tile Start tile.
 136  * @param delta Movement direction.
 137  * @param check_type Stop when the custom station type changes.
 138  * @param check_axis Stop when the station direction changes.
 139  * @return Found end of the railway station.
 140  */
 141 static TileIndex FindRailStationEnd(TileIndex tile, TileIndexDiff delta, bool check_type, bool check_axis)
 142 {
 143         byte orig_type = 0;
 144         Axis orig_axis = AXIS_X;
 145         StationID sid = GetStationIndex(tile);
 146
 147         if (check_type) orig_type = GetCustomStationSpecIndex(tile);
 148         if (check_axis) orig_axis = GetRailStationAxis(tile);
 149
 150         for (;;) {
 151                 TileIndex new_tile = TILE_ADD(tile, delta);
 152
 153                 if (!IsTileType(new_tile, MP_STATION) || GetStationIndex(new_tile) != sid) break;
 154                 if (!HasStationRail(new_tile)) break;
 155                 if (check_type && GetCustomStationSpecIndex(new_tile) != orig_type) break;
 156                 if (check_axis && GetRailStationAxis(new_tile) != orig_axis) break;
 157
 158                 tile = new_tile;
 159         }
 160         return tile;
 161 }
 162
 163
 164 static uint32_t GetPlatformInfoHelper(TileIndex tile, bool check_type, bool check_axis, bool centred)
 165 {
 166         int tx = TileX(tile);
 167         int ty = TileY(tile);
 168         int sx = TileX(FindRailStationEnd(tile, TileDiffXY(-1,  0), check_type, check_axis));
 169         int sy = TileY(FindRailStationEnd(tile, TileDiffXY( 0, -1), check_type, check_axis));
 170         int ex = TileX(FindRailStationEnd(tile, TileDiffXY( 1,  0), check_type, check_axis)) + 1;
 171         int ey = TileY(FindRailStationEnd(tile, TileDiffXY( 0,  1), check_type, check_axis)) + 1;
 172
 173         tx -= sx; ex -= sx;
 174         ty -= sy; ey -= sy;
 175
 176         return GetPlatformInfo(GetRailStationAxis(tile), GetStationGfx(tile), ex, ey, tx, ty, centred);
 177 }
 178
 179
 180 static uint32_t GetRailContinuationInfo(TileIndex tile)
 181 {
 182         /* Tile offsets and exit dirs for X axis */
 183         static const Direction x_dir[8] = { DIR_SW, DIR_NE, DIR_SE, DIR_NW, DIR_S, DIR_E, DIR_W, DIR_N };
 184         static const DiagDirection x_exits[8] = { DIAGDIR_SW, DIAGDIR_NE, DIAGDIR_SE, DIAGDIR_NW, DIAGDIR_SW, DIAGDIR_NE, DIAGDIR_SW, DIAGDIR_NE };
 185
 186         /* Tile offsets and exit dirs for Y axis */
 187         static const Direction y_dir[8] = { DIR_SE, DIR_NW, DIR_SW, DIR_NE, DIR_S, DIR_W, DIR_E, DIR_N };
 188         static const DiagDirection y_exits[8] = { DIAGDIR_SE, DIAGDIR_NW, DIAGDIR_SW, DIAGDIR_NE, DIAGDIR_SE, DIAGDIR_NW, DIAGDIR_SE, DIAGDIR_NW };
 189
 190         Axis axis = GetRailStationAxis(tile);
 191
 192         /* Choose appropriate lookup table to use */
 193         const Direction *dir = axis == AXIS_X ? x_dir : y_dir;
 194         const DiagDirection *diagdir = axis == AXIS_X ? x_exits : y_exits;
 195
 196         uint32_t res = 0;
 197         uint i;
 198
 199         for (i = 0; i < lengthof(x_dir); i++, dir++, diagdir++) {
 200                 TileIndex neighbour_tile = tile + TileOffsByDir(*dir);
 201                 TrackBits trackbits = TrackStatusToTrackBits(GetTileTrackStatus(neighbour_tile, TRANSPORT_RAIL, 0));
 202                 if (trackbits != TRACK_BIT_NONE) {
 203                         /* If there is any track on the tile, set the bit in the second byte */
 204                         SetBit(res, i + 8);
 205
 206                         /* With tunnels and bridges the tile has tracks, but they are not necessarily connected
 207                          * with the next tile because the ramp is not going in the right direction. */
 208                         if (IsTileType(neighbour_tile, MP_TUNNELBRIDGE) && GetTunnelBridgeDirection(neighbour_tile) != *diagdir) {
 209                                 continue;
 210                         }
 211
 212                         /* If any track reaches our exit direction, set the bit in the lower byte */
 213                         if (trackbits & DiagdirReachesTracks(*diagdir)) SetBit(res, i);
 214                 }
 215         }
 216
 217         return res;
 218 }
 219
 220
 221 /* Station Resolver Functions */
 222 /* virtual */ uint32_t StationScopeResolver::GetRandomBits() const
 223 {
 224         return (this->st == nullptr ? 0 : this->st->random_bits) | (this->tile == INVALID_TILE ? 0 : GetStationTileRandomBits(this->tile) << 16);
 225 }
 226
 227
 228 /* virtual */ uint32_t StationScopeResolver::GetTriggers() const
 229 {
 230         return this->st == nullptr ? 0 : this->st->waiting_triggers;
 231 }
 232
 233
 234 /**
 235  * Station variable cache
 236  * This caches 'expensive' station variable lookups which iterate over
 237  * several tiles that may be called multiple times per Resolve().
 238  */
 239 static struct {
 240         uint32_t v40;
 241         uint32_t v41;
 242         uint32_t v45;
 243         uint32_t v46;
 244         uint32_t v47;
 245         uint32_t v49;
 246         uint8_t valid; ///< Bits indicating what variable is valid (for each bit, \c 0 is invalid, \c 1 is valid).
 247 } _svc;
 248
 249 /**
 250  * Get the town scope associated with a station, if it exists.
 251  * On the first call, the town scope is created (if possible).
 252  * @return Town scope, if available.
 253  */
 254 TownScopeResolver *StationResolverObject::GetTown()
 255 {
 256         if (this->town_scope == nullptr) {
 257                 Town *t = nullptr;
 258                 if (this->station_scope.st != nullptr) {
 259                         t = this->station_scope.st->town;
 260                 } else if (this->station_scope.tile != INVALID_TILE) {
 261                         t = ClosestTownFromTile(this->station_scope.tile, UINT_MAX);
 262                 }
 263                 if (t == nullptr) return nullptr;
 264                 this->town_scope = new TownScopeResolver(*this, t, this->station_scope.st == nullptr);
 265         }
 266         return this->town_scope;
 267 }
 268
 269 /* virtual */ uint32_t StationScopeResolver::GetVariable(byte variable, [[maybe_unused]] uint32_t parameter, bool *available) const
 270 {
 271         if (this->st == nullptr) {
 272                 /* Station does not exist, so we're in a purchase list or the land slope check callback. */
 273                 switch (variable) {
 274                         case 0x40:
 275                         case 0x41:
 276                         case 0x46:
 277                         case 0x47:
 278                         case 0x49: return 0x2110000;        // Platforms, tracks & position
 279                         case 0x42: return 0;                // Rail type (XXX Get current type from GUI?)
 280                         case 0x43: return GetCompanyInfo(_current_company); // Station owner
 281                         case 0x44: return 2;                // PBS status
 282                         case 0x67: // Land info of nearby tile
 283                                 if (this->axis != INVALID_AXIS && this->tile != INVALID_TILE) {
 284                                         TileIndex tile = this->tile;
 285                                         if (parameter != 0) tile = GetNearbyTile(parameter, tile, true, this->axis); // only perform if it is required
 286
 287                                         Slope tileh = GetTileSlope(tile);
 288                                         bool swap = (this->axis == AXIS_Y && HasBit(tileh, CORNER_W) != HasBit(tileh, CORNER_E));
 289
 290                                         return GetNearbyTileInformation(tile, this->ro.grffile->grf_version >= 8) ^ (swap ? SLOPE_EW : 0);
 291                                 }
 292                                 break;
 293
 294                         case 0xFA: return ClampTo<uint16_t>(TimerGameCalendar::date - CalendarTime::DAYS_TILL_ORIGINAL_BASE_YEAR); // Build date, clamped to a 16 bit value
 295                 }
 296
 297                 *available = false;
 298                 return UINT_MAX;
 299         }
 300
 301         switch (variable) {
 302                 /* Calculated station variables */
 303                 case 0x40:
 304                         if (!HasBit(_svc.valid, 0)) { _svc.v40 = GetPlatformInfoHelper(this->tile, false, false, false); SetBit(_svc.valid, 0); }
 305                         return _svc.v40;
 306
 307                 case 0x41:
 308                         if (!HasBit(_svc.valid, 1)) { _svc.v41 = GetPlatformInfoHelper(this->tile, true,  false, false); SetBit(_svc.valid, 1); }
 309                         return _svc.v41;
 310
 311                 case 0x42: return GetTerrainType(this->tile) | (GetReverseRailTypeTranslation(GetRailType(this->tile), this->statspec->grf_prop.grffile) << 8);
 312                 case 0x43: return GetCompanyInfo(this->st->owner); // Station owner
 313                 case 0x44: return HasStationReservation(this->tile) ? 7 : 4; // PBS status
 314                 case 0x45:
 315                         if (!HasBit(_svc.valid, 2)) { _svc.v45 = GetRailContinuationInfo(this->tile); SetBit(_svc.valid, 2); }
 316                         return _svc.v45;
 317
 318                 case 0x46:
 319                         if (!HasBit(_svc.valid, 3)) { _svc.v46 = GetPlatformInfoHelper(this->tile, false, false, true); SetBit(_svc.valid, 3); }
 320                         return _svc.v46;
 321
 322                 case 0x47:
 323                         if (!HasBit(_svc.valid, 4)) { _svc.v47 = GetPlatformInfoHelper(this->tile, true,  false, true); SetBit(_svc.valid, 4); }
 324                         return _svc.v47;
 325
 326                 case 0x49:
 327                         if (!HasBit(_svc.valid, 5)) { _svc.v49 = GetPlatformInfoHelper(this->tile, false, true, false); SetBit(_svc.valid, 5); }
 328                         return _svc.v49;
 329
 330                 case 0x4A: // Animation frame of tile
 331                         return GetAnimationFrame(this->tile);
 332
 333                 /* Variables which use the parameter */
 334                 /* Variables 0x60 to 0x65 and 0x69 are handled separately below */
 335                 case 0x66: { // Animation frame of nearby tile
 336                         TileIndex tile = this->tile;
 337                         if (parameter != 0) tile = GetNearbyTile(parameter, tile);
 338                         return this->st->TileBelongsToRailStation(tile) ? GetAnimationFrame(tile) : UINT_MAX;
 339                 }
 340
 341                 case 0x67: { // Land info of nearby tile
 342                         Axis axis = GetRailStationAxis(this->tile);
 343                         TileIndex tile = this->tile;
 344                         if (parameter != 0) tile = GetNearbyTile(parameter, tile); // only perform if it is required
 345
 346                         Slope tileh = GetTileSlope(tile);
 347                         bool swap = (axis == AXIS_Y && HasBit(tileh, CORNER_W) != HasBit(tileh, CORNER_E));
 348
 349                         return GetNearbyTileInformation(tile, this->ro.grffile->grf_version >= 8) ^ (swap ? SLOPE_EW : 0);
 350                 }
 351
 352                 case 0x68: { // Station info of nearby tiles
 353                         TileIndex nearby_tile = GetNearbyTile(parameter, this->tile);
 354
 355                         if (!HasStationTileRail(nearby_tile)) return 0xFFFFFFFF;
 356
 357                         uint32_t grfid = this->st->speclist[GetCustomStationSpecIndex(this->tile)].grfid;
 358                         bool perpendicular = GetRailStationAxis(this->tile) != GetRailStationAxis(nearby_tile);
 359                         bool same_station = this->st->TileBelongsToRailStation(nearby_tile);
 360                         uint32_t res = GB(GetStationGfx(nearby_tile), 1, 2) << 12 | !!perpendicular << 11 | !!same_station << 10;
 361
 362                         if (IsCustomStationSpecIndex(nearby_tile)) {
 363                                 const StationSpecList ssl = BaseStation::GetByTile(nearby_tile)->speclist[GetCustomStationSpecIndex(nearby_tile)];
 364                                 res |= 1 << (ssl.grfid != grfid ? 9 : 8) | ClampTo<uint8_t>(ssl.localidx);
 365                         }
 366                         return res;
 367                 }
 368
 369                 case 0x6A: { // GRFID of nearby station tiles
 370                         TileIndex nearby_tile = GetNearbyTile(parameter, this->tile);
 371
 372                         if (!HasStationTileRail(nearby_tile)) return 0xFFFFFFFF;
 373                         if (!IsCustomStationSpecIndex(nearby_tile)) return 0;
 374
 375                         const StationSpecList ssl = BaseStation::GetByTile(nearby_tile)->speclist[GetCustomStationSpecIndex(nearby_tile)];
 376                         return ssl.grfid;
 377                 }
 378
 379                 case 0x6B: { // 16 bit Station ID of nearby tiles
 380                         TileIndex nearby_tile = GetNearbyTile(parameter, this->tile);
 381
 382                         if (!HasStationTileRail(nearby_tile)) return 0xFFFFFFFF;
 383                         if (!IsCustomStationSpecIndex(nearby_tile)) return 0xFFFE;
 384
 385                         uint32_t grfid = this->st->speclist[GetCustomStationSpecIndex(this->tile)].grfid;
 386
 387                         const StationSpecList ssl = BaseStation::GetByTile(nearby_tile)->speclist[GetCustomStationSpecIndex(nearby_tile)];
 388                         if (ssl.grfid == grfid) {
 389                                 return ssl.localidx;
 390                         }
 391
 392                         return 0xFFFE;
 393                 }
 394
 395                 /* General station variables */
 396                 case 0x82: return 50;
 397                 case 0x84: return this->st->string_id;
 398                 case 0x86: return 0;
 399                 case 0xF0: return this->st->facilities;
 400                 case 0xFA: return ClampTo<uint16_t>(this->st->build_date - CalendarTime::DAYS_TILL_ORIGINAL_BASE_YEAR);
 401         }
 402
 403         return this->st->GetNewGRFVariable(this->ro, variable, parameter, available);
 404 }
 405
 406 uint32_t Station::GetNewGRFVariable(const ResolverObject &object, byte variable, byte parameter, bool *available) const
 407 {
 408         switch (variable) {
 409                 case 0x48: { // Accepted cargo types
 410                         uint32_t value = GetAcceptanceMask(this);
 411                         return value;
 412                 }
 413
 414                 case 0x8A: return this->had_vehicle_of_type;
 415                 case 0xF1: return (this->airport.tile != INVALID_TILE) ? this->airport.GetSpec()->ttd_airport_type : ATP_TTDP_LARGE;
 416                 case 0xF2: return (this->truck_stops != nullptr) ? this->truck_stops->status : 0;
 417                 case 0xF3: return (this->bus_stops != nullptr)   ? this->bus_stops->status   : 0;
 418                 case 0xF6: return this->airport.flags;
 419                 case 0xF7: return GB(this->airport.flags, 8, 8);
 420         }
 421
 422         /* Handle cargo variables with parameter, 0x60 to 0x65 and 0x69 */
 423         if ((variable >= 0x60 && variable <= 0x65) || variable == 0x69) {
 424                 CargoID c = GetCargoTranslation(parameter, object.grffile);
 425
 426                 if (!IsValidCargoID(c)) {
 427                         switch (variable) {
 428                                 case 0x62: return 0xFFFFFFFF;
 429                                 case 0x64: return 0xFF00;
 430                                 default:   return 0;
 431                         }
 432                 }
 433                 const GoodsEntry *ge = &this->goods[c];
 434
 435                 switch (variable) {
 436                         case 0x60: return std::min(ge->cargo.TotalCount(), 4095u);
 437                         case 0x61: return ge->HasVehicleEverTriedLoading() ? ge->time_since_pickup : 0;
 438                         case 0x62: return ge->HasRating() ? ge->rating : 0xFFFFFFFF;
 439                         case 0x63: return ge->cargo.PeriodsInTransit();
 440                         case 0x64: return ge->HasVehicleEverTriedLoading() ? ge->last_speed | (ge->last_age << 8) : 0xFF00;
 441                         case 0x65: return GB(ge->status, GoodsEntry::GES_ACCEPTANCE, 1) << 3;
 442                         case 0x69: {
 443                                 static_assert((int)GoodsEntry::GES_EVER_ACCEPTED + 1 == (int)GoodsEntry::GES_LAST_MONTH);
 444                                 static_assert((int)GoodsEntry::GES_EVER_ACCEPTED + 2 == (int)GoodsEntry::GES_CURRENT_MONTH);
 445                                 static_assert((int)GoodsEntry::GES_EVER_ACCEPTED + 3 == (int)GoodsEntry::GES_ACCEPTED_BIGTICK);
 446                                 return GB(ge->status, GoodsEntry::GES_EVER_ACCEPTED, 4);
 447                         }
 448                 }
 449         }
 450
 451         /* Handle cargo variables (deprecated) */
 452         if (variable >= 0x8C && variable <= 0xEC) {
 453                 const GoodsEntry *g = &this->goods[GB(variable - 0x8C, 3, 4)];
 454                 switch (GB(variable - 0x8C, 0, 3)) {
 455                         case 0: return g->cargo.TotalCount();
 456                         case 1: return GB(std::min(g->cargo.TotalCount(), 4095u), 0, 4) | (GB(g->status, GoodsEntry::GES_ACCEPTANCE, 1) << 7);
 457                         case 2: return g->time_since_pickup;
 458                         case 3: return g->rating;
 459                         case 4: return g->cargo.GetFirstStation();
 460                         case 5: return g->cargo.PeriodsInTransit();
 461                         case 6: return g->last_speed;
 462                         case 7: return g->last_age;
 463                 }
 464         }
 465
 466         Debug(grf, 1, "Unhandled station variable 0x{:X}", variable);
 467
 468         *available = false;
 469         return UINT_MAX;
 470 }
 471
 472 uint32_t Waypoint::GetNewGRFVariable(const ResolverObject &, byte variable, [[maybe_unused]] byte parameter, bool *available) const
 473 {
 474         switch (variable) {
 475                 case 0x48: return 0; // Accepted cargo types
 476                 case 0x8A: return HVOT_WAYPOINT;
 477                 case 0xF1: return 0; // airport type
 478                 case 0xF2: return 0; // truck stop status
 479                 case 0xF3: return 0; // bus stop status
 480                 case 0xF6: return 0; // airport flags
 481                 case 0xF7: return 0; // airport flags cont.
 482         }
 483
 484         /* Handle cargo variables with parameter, 0x60 to 0x65 */
 485         if (variable >= 0x60 && variable <= 0x65) {
 486                 return 0;
 487         }
 488
 489         /* Handle cargo variables (deprecated) */
 490         if (variable >= 0x8C && variable <= 0xEC) {
 491                 switch (GB(variable - 0x8C, 0, 3)) {
 492                         case 3: return INITIAL_STATION_RATING;
 493                         case 4: return INVALID_STATION;
 494                         default: return 0;
 495                 }
 496         }
 497
 498         Debug(grf, 1, "Unhandled station variable 0x{:X}", variable);
 499
 500         *available = false;
 501         return UINT_MAX;
 502 }
 503
 504 /* virtual */ const SpriteGroup *StationResolverObject::ResolveReal(const RealSpriteGroup *group) const
 505 {
 506         if (this->station_scope.st == nullptr || this->station_scope.statspec->cls_id == STAT_CLASS_WAYP) {
 507                 return group->loading[0];
 508         }
 509
 510         uint cargo = 0;
 511         const Station *st = Station::From(this->station_scope.st);
 512
 513         switch (this->station_scope.cargo_type) {
 514                 case INVALID_CARGO:
 515                 case SpriteGroupCargo::SG_DEFAULT_NA:
 516                 case SpriteGroupCargo::SG_PURCHASE:
 517                         cargo = 0;
 518                         break;
 519
 520                 case SpriteGroupCargo::SG_DEFAULT:
 521                         for (const GoodsEntry &ge : st->goods) {
 522                                 cargo += ge.cargo.TotalCount();
 523                         }
 524                         break;
 525
 526                 default:
 527                         cargo = st->goods[this->station_scope.cargo_type].cargo.TotalCount();
 528                         break;
 529         }
 530
 531         if (HasBit(this->station_scope.statspec->flags, SSF_DIV_BY_STATION_SIZE)) cargo /= (st->train_station.w + st->train_station.h);
 532         cargo = std::min(0xfffu, cargo);
 533
 534         if (cargo > this->station_scope.statspec->cargo_threshold) {
 535                 if (!group->loading.empty()) {
 536                         uint set = ((cargo - this->station_scope.statspec->cargo_threshold) * (uint)group->loading.size()) / (4096 - this->station_scope.statspec->cargo_threshold);
 537                         return group->loading[set];
 538                 }
 539         } else {
 540                 if (!group->loaded.empty()) {
 541                         uint set = (cargo * (uint)group->loaded.size()) / (this->station_scope.statspec->cargo_threshold + 1);
 542                         return group->loaded[set];
 543                 }
 544         }
 545
 546         return group->loading[0];
 547 }
 548
 549 GrfSpecFeature StationResolverObject::GetFeature() const
 550 {
 551         return GSF_STATIONS;
 552 }
 553
 554 uint32_t StationResolverObject::GetDebugID() const
 555 {
 556         return this->station_scope.statspec->grf_prop.local_id;
 557 }
 558
 559 /**
 560  * Resolver for stations.
 561  * @param statspec Station (type) specification.
 562  * @param base_station Instance of the station.
 563  * @param tile %Tile of the station.
 564  * @param callback Callback ID.
 565  * @param callback_param1 First parameter (var 10) of the callback.
 566  * @param callback_param2 Second parameter (var 18) of the callback.
 567  */
 568 StationResolverObject::StationResolverObject(const StationSpec *statspec, BaseStation *base_station, TileIndex tile,
 569                 CallbackID callback, uint32_t callback_param1, uint32_t callback_param2)
 570         : ResolverObject(statspec->grf_prop.grffile, callback, callback_param1, callback_param2),
 571         station_scope(*this, statspec, base_station, tile), town_scope(nullptr)
 572 {
 573         /* Invalidate all cached vars */
 574         _svc.valid = 0;
 575
 576         CargoID ctype = SpriteGroupCargo::SG_DEFAULT_NA;
 577
 578         if (this->station_scope.st == nullptr) {
 579                 /* No station, so we are in a purchase list */
 580                 ctype = SpriteGroupCargo::SG_PURCHASE;
 581         } else if (Station::IsExpected(this->station_scope.st)) {
 582                 const Station *st = Station::From(this->station_scope.st);
 583                 /* Pick the first cargo that we have waiting */
 584                 for (const CargoSpec *cs : CargoSpec::Iterate()) {
 585                         if (this->station_scope.statspec->grf_prop.spritegroup[cs->Index()] != nullptr &&
 586                                         st->goods[cs->Index()].cargo.TotalCount() > 0) {
 587                                 ctype = cs->Index();
 588                                 break;
 589                         }
 590                 }
 591         }
 592
 593         if (this->station_scope.statspec->grf_prop.spritegroup[ctype] == nullptr) {
 594                 ctype = SpriteGroupCargo::SG_DEFAULT;
 595         }
 596
 597         /* Remember the cargo type we've picked */
 598         this->station_scope.cargo_type = ctype;
 599         this->root_spritegroup = this->station_scope.statspec->grf_prop.spritegroup[this->station_scope.cargo_type];
 600 }
 601
 602 StationResolverObject::~StationResolverObject()
 603 {
 604         delete this->town_scope;
 605 }
 606
 607 /**
 608  * Resolve sprites for drawing a station tile.
 609  * @param statspec Station spec
 610  * @param st Station (nullptr in GUI)
 611  * @param tile Station tile being drawn (INVALID_TILE in GUI)
 612  * @param var10 Value to put in variable 10; normally 0; 1 when resolving the groundsprite and SSF_SEPARATE_GROUND is set.
 613  * @return First sprite of the Action 1 spriteset to use, minus an offset of 0x42D to accommodate for weird NewGRF specs.
 614  */
 615 SpriteID GetCustomStationRelocation(const StationSpec *statspec, BaseStation *st, TileIndex tile, uint32_t var10)
 616 {
 617         StationResolverObject object(statspec, st, tile, CBID_NO_CALLBACK, var10);
 618         const SpriteGroup *group = object.Resolve();
 619         if (group == nullptr || group->type != SGT_RESULT) return 0;
 620         return group->GetResult() - 0x42D;
 621 }
 622
 623 /**
 624  * Resolve the sprites for custom station foundations.
 625  * @param statspec Station spec
 626  * @param st Station
 627  * @param tile Station tile being drawn
 628  * @param layout Spritelayout as returned by previous callback
 629  * @param edge_info Information about northern tile edges; whether they need foundations or merge into adjacent tile's foundations.
 630  * @return First sprite of a set of foundation sprites for various slopes, or 0 if default foundations shall be drawn.
 631  */
 632 SpriteID GetCustomStationFoundationRelocation(const StationSpec *statspec, BaseStation *st, TileIndex tile, uint layout, uint edge_info)
 633 {
 634         /* callback_param1 == 2 means  we are resolving the foundation sprites. */
 635         StationResolverObject object(statspec, st, tile, CBID_NO_CALLBACK, 2, layout | (edge_info << 16));
 636
 637         const SpriteGroup *group = object.Resolve();
 638         if (group == nullptr || group->type != SGT_RESULT) return 0;
 639
 640         /* Note: SpriteGroup::Resolve zeroes all registers, so register 0x100 is initialised to 0. (compatibility) */
 641         return group->GetResult() + GetRegister(0x100);
 642 }
 643
 644
 645 uint16_t GetStationCallback(CallbackID callback, uint32_t param1, uint32_t param2, const StationSpec *statspec, BaseStation *st, TileIndex tile)
 646 {
 647         StationResolverObject object(statspec, st, tile, callback, param1, param2);
 648         return object.ResolveCallback();
 649 }
 650
 651 /**
 652  * Check the slope of a tile of a new station.
 653  * @param north_tile Norther tile of the station rect.
 654  * @param cur_tile Tile to check.
 655  * @param statspec Station spec.
 656  * @param axis Axis of the new station.
 657  * @param plat_len Platform length.
 658  * @param numtracks Number of platforms.
 659  * @return Succeeded or failed command.
 660  */
 661 CommandCost PerformStationTileSlopeCheck(TileIndex north_tile, TileIndex cur_tile, const StationSpec *statspec, Axis axis, byte plat_len, byte numtracks)
 662 {
 663         TileIndex diff = cur_tile - north_tile;
 664         Slope slope = GetTileSlope(cur_tile);
 665
 666         StationResolverObject object(statspec, nullptr, cur_tile, CBID_STATION_LAND_SLOPE_CHECK,
 667                         (slope << 4) | (slope ^ (axis == AXIS_Y && HasBit(slope, CORNER_W) != HasBit(slope, CORNER_E) ? SLOPE_EW : 0)),
 668                         (numtracks << 24) | (plat_len << 16) | (axis == AXIS_Y ? TileX(diff) << 8 | TileY(diff) : TileY(diff) << 8 | TileX(diff)));
 669         object.station_scope.axis = axis;
 670
 671         uint16_t cb_res = object.ResolveCallback();
 672
 673         /* Failed callback means success. */
 674         if (cb_res == CALLBACK_FAILED) return CommandCost();
 675
 676         /* The meaning of bit 10 is inverted for a grf version < 8. */
 677         if (statspec->grf_prop.grffile->grf_version < 8) ToggleBit(cb_res, 10);
 678         return GetErrorMessageFromLocationCallbackResult(cb_res, statspec->grf_prop.grffile, STR_ERROR_LAND_SLOPED_IN_WRONG_DIRECTION);
 679 }
 680
 681
 682 /**
 683  * Allocate a StationSpec to a Station. This is called once per build operation.
 684  * @param statspec StationSpec to allocate.
 685  * @param st Station to allocate it to.
 686  * @param exec Whether to actually allocate the spec.
 687  * @return Index within the Station's spec list, or -1 if the allocation failed.
 688  */
 689 int AllocateSpecToStation(const StationSpec *statspec, BaseStation *st, bool exec)
 690 {
 691         uint i;
 692
 693         if (statspec == nullptr || st == nullptr) return 0;
 694
 695         for (i = 1; i < st->speclist.size() && i < NUM_STATIONSSPECS_PER_STATION; i++) {
 696                 if (st->speclist[i].spec == nullptr && st->speclist[i].grfid == 0) break;
 697         }
 698
 699         if (i == NUM_STATIONSSPECS_PER_STATION) {
 700                 /* As final effort when the spec list is already full...
 701                  * try to find the same spec and return that one. This might
 702                  * result in slightly "wrong" (as per specs) looking stations,
 703                  * but it's fairly unlikely that one reaches the limit anyways.
 704                  */
 705                 for (i = 1; i < st->speclist.size() && i < NUM_STATIONSSPECS_PER_STATION; i++) {
 706                         if (st->speclist[i].spec == statspec) return i;
 707                 }
 708
 709                 return -1;
 710         }
 711
 712         if (exec) {
 713                 if (i >= st->speclist.size()) st->speclist.resize(i + 1);
 714                 st->speclist[i].spec     = statspec;
 715                 st->speclist[i].grfid    = statspec->grf_prop.grffile->grfid;
 716                 st->speclist[i].localidx = statspec->grf_prop.local_id;
 717
 718                 StationUpdateCachedTriggers(st);
 719         }
 720
 721         return i;
 722 }
 723
 724
 725 /**
 726  * Deallocate a StationSpec from a Station. Called when removing a single station tile.
 727  * @param st Station to work with.
 728  * @param specindex Index of the custom station within the Station's spec list.
 729  * @return Indicates whether the StationSpec was deallocated.
 730  */
 731 void DeallocateSpecFromStation(BaseStation *st, byte specindex)
 732 {
 733         /* specindex of 0 (default) is never freeable */
 734         if (specindex == 0) return;
 735
 736         ETileArea area = ETileArea(st, INVALID_TILE, TA_WHOLE);
 737         /* Check all tiles over the station to check if the specindex is still in use */
 738         for (TileIndex tile : area) {
 739                 if (st->TileBelongsToRailStation(tile) && GetCustomStationSpecIndex(tile) == specindex) {
 740                         return;
 741                 }
 742         }
 743
 744         /* This specindex is no longer in use, so deallocate it */
 745         st->speclist[specindex].spec     = nullptr;
 746         st->speclist[specindex].grfid    = 0;
 747         st->speclist[specindex].localidx = 0;
 748
 749         /* If this was the highest spec index, reallocate */
 750         if (specindex == st->speclist.size() - 1) {
 751                 size_t num_specs;
 752                 for (num_specs = st->speclist.size() - 1; num_specs > 0; num_specs--) {
 753                         if (st->speclist[num_specs].grfid != 0) break;
 754                 }
 755
 756                 if (num_specs > 0) {
 757                         st->speclist.resize(num_specs + 1);
 758                 } else {
 759                         st->speclist.clear();
 760                         st->cached_anim_triggers = 0;
 761                         st->cached_cargo_triggers = 0;
 762                         return;
 763                 }
 764         }
 765
 766         StationUpdateCachedTriggers(st);
 767 }
 768
 769 /**
 770  * Draw representation of a station tile for GUI purposes.
 771  * @param x Position x of image.
 772  * @param y Position y of image.
 773  * @param axis Axis.
 774  * @param railtype Rail type.
 775  * @param sclass, station Type of station.
 776  * @param station station ID
 777  * @return True if the tile was drawn (allows for fallback to default graphic)
 778  */
 779 bool DrawStationTile(int x, int y, RailType railtype, Axis axis, StationClassID sclass, uint station)
 780 {
 781         const DrawTileSprites *sprites = nullptr;
 782         const RailTypeInfo *rti = GetRailTypeInfo(railtype);
 783         PaletteID palette = COMPANY_SPRITE_COLOUR(_local_company);
 784         uint tile = 2;
 785
 786         const StationSpec *statspec = StationClass::Get(sclass)->GetSpec(station);
 787         if (statspec == nullptr) return false;
 788
 789         if (HasBit(statspec->callback_mask, CBM_STATION_SPRITE_LAYOUT)) {
 790                 uint16_t callback = GetStationCallback(CBID_STATION_SPRITE_LAYOUT, 0, 0, statspec, nullptr, INVALID_TILE);
 791                 if (callback != CALLBACK_FAILED) tile = callback & ~1;
 792         }
 793
 794         uint32_t total_offset = rti->GetRailtypeSpriteOffset();
 795         uint32_t relocation = 0;
 796         uint32_t ground_relocation = 0;
 797         const NewGRFSpriteLayout *layout = nullptr;
 798         DrawTileSprites tmp_rail_layout;
 799
 800         if (statspec->renderdata.empty()) {
 801                 sprites = GetStationTileLayout(STATION_RAIL, tile + axis);
 802         } else {
 803                 layout = &statspec->renderdata[(tile < statspec->renderdata.size()) ? tile + axis : (uint)axis];
 804                 if (!layout->NeedsPreprocessing()) {
 805                         sprites = layout;
 806                         layout = nullptr;
 807                 }
 808         }
 809
 810         if (layout != nullptr) {
 811                 /* Sprite layout which needs preprocessing */
 812                 bool separate_ground = HasBit(statspec->flags, SSF_SEPARATE_GROUND);
 813                 uint32_t var10_values = layout->PrepareLayout(total_offset, rti->fallback_railtype, 0, 0, separate_ground);
 814                 for (uint8_t var10 : SetBitIterator(var10_values)) {
 815                         uint32_t var10_relocation = GetCustomStationRelocation(statspec, nullptr, INVALID_TILE, var10);
 816                         layout->ProcessRegisters(var10, var10_relocation, separate_ground);
 817                 }
 818
 819                 tmp_rail_layout.seq = layout->GetLayout(&tmp_rail_layout.ground);
 820                 sprites = &tmp_rail_layout;
 821                 total_offset = 0;
 822         } else {
 823                 /* Simple sprite layout */
 824                 ground_relocation = relocation = GetCustomStationRelocation(statspec, nullptr, INVALID_TILE, 0);
 825                 if (HasBit(sprites->ground.sprite, SPRITE_MODIFIER_CUSTOM_SPRITE)) {
 826                         ground_relocation = GetCustomStationRelocation(statspec, nullptr, INVALID_TILE, 1);
 827                 }
 828                 ground_relocation += rti->fallback_railtype;
 829         }
 830
 831         SpriteID image = sprites->ground.sprite;
 832         PaletteID pal = sprites->ground.pal;
 833         RailTrackOffset overlay_offset;
 834         if (rti->UsesOverlay() && SplitGroundSpriteForOverlay(nullptr, &image, &overlay_offset)) {
 835                 SpriteID ground = GetCustomRailSprite(rti, INVALID_TILE, RTSG_GROUND);
 836                 DrawSprite(image, PAL_NONE, x, y);
 837                 DrawSprite(ground + overlay_offset, PAL_NONE, x, y);
 838         } else {
 839                 image += HasBit(image, SPRITE_MODIFIER_CUSTOM_SPRITE) ? ground_relocation : total_offset;
 840                 if (HasBit(pal, SPRITE_MODIFIER_CUSTOM_SPRITE)) pal += ground_relocation;
 841                 DrawSprite(image, GroundSpritePaletteTransform(image, pal, palette), x, y);
 842         }
 843
 844         DrawRailTileSeqInGUI(x, y, sprites, total_offset, relocation, palette);
 845
 846         return true;
 847 }
 848
 849
 850 const StationSpec *GetStationSpec(TileIndex t)
 851 {
 852         if (!IsCustomStationSpecIndex(t)) return nullptr;
 853
 854         const BaseStation *st = BaseStation::GetByTile(t);
 855         uint specindex = GetCustomStationSpecIndex(t);
 856         return specindex < st->speclist.size() ? st->speclist[specindex].spec : nullptr;
 857 }
 858
 859 /** Wrapper for animation control, see GetStationCallback. */
 860 uint16_t GetAnimStationCallback(CallbackID callback, uint32_t param1, uint32_t param2, const StationSpec *statspec, BaseStation *st, TileIndex tile, int)
 861 {
 862         return GetStationCallback(callback, param1, param2, statspec, st, tile);
 863 }
 864
 865 /** Helper class for animation control. */
 866 struct StationAnimationBase : public AnimationBase<StationAnimationBase, StationSpec, BaseStation, int, GetAnimStationCallback, TileAnimationFrameAnimationHelper<BaseStation> > {
 867         static const CallbackID cb_animation_speed      = CBID_STATION_ANIMATION_SPEED;
 868         static const CallbackID cb_animation_next_frame = CBID_STATION_ANIM_NEXT_FRAME;
 869
 870         static const StationCallbackMask cbm_animation_speed      = CBM_STATION_ANIMATION_SPEED;
 871         static const StationCallbackMask cbm_animation_next_frame = CBM_STATION_ANIMATION_NEXT_FRAME;
 872 };
 873
 874 void AnimateStationTile(TileIndex tile)
 875 {
 876         const StationSpec *ss = GetStationSpec(tile);
 877         if (ss == nullptr) return;
 878
 879         StationAnimationBase::AnimateTile(ss, BaseStation::GetByTile(tile), tile, HasBit(ss->flags, SSF_CB141_RANDOM_BITS));
 880 }
 881
 882 void TriggerStationAnimation(BaseStation *st, TileIndex trigger_tile, StationAnimationTrigger trigger, CargoID cargo_type)
 883 {
 884         /* List of coverage areas for each animation trigger */
 885         static const TriggerArea tas[] = {
 886                 TA_TILE, TA_WHOLE, TA_WHOLE, TA_PLATFORM, TA_PLATFORM, TA_PLATFORM, TA_WHOLE
 887         };
 888
 889         /* Get Station if it wasn't supplied */
 890         if (st == nullptr) st = BaseStation::GetByTile(trigger_tile);
 891
 892         /* Check the cached animation trigger bitmask to see if we need
 893          * to bother with any further processing. */
 894         if (!HasBit(st->cached_anim_triggers, trigger)) return;
 895
 896         uint16_t random_bits = Random();
 897         ETileArea area = ETileArea(st, trigger_tile, tas[trigger]);
 898
 899         /* Check all tiles over the station to check if the specindex is still in use */
 900         for (TileIndex tile : area) {
 901                 if (st->TileBelongsToRailStation(tile)) {
 902                         const StationSpec *ss = GetStationSpec(tile);
 903                         if (ss != nullptr && HasBit(ss->animation.triggers, trigger)) {
 904                                 CargoID cargo;
 905                                 if (!IsValidCargoID(cargo_type)) {
 906                                         cargo = INVALID_CARGO;
 907                                 } else {
 908                                         cargo = ss->grf_prop.grffile->cargo_map[cargo_type];
 909                                 }
 910                                 StationAnimationBase::ChangeAnimationFrame(CBID_STATION_ANIM_START_STOP, ss, st, tile, (random_bits << 16) | GB(Random(), 0, 16), (uint8_t)trigger | (cargo << 8));
 911                         }
 912                 }
 913         }
 914 }
 915
 916 /**
 917  * Trigger station randomisation
 918  * @param st station being triggered
 919  * @param trigger_tile specific tile of platform to trigger
 920  * @param trigger trigger type
 921  * @param cargo_type cargo type causing trigger
 922  */
 923 void TriggerStationRandomisation(Station *st, TileIndex trigger_tile, StationRandomTrigger trigger, CargoID cargo_type)
 924 {
 925         /* List of coverage areas for each animation trigger */
 926         static const TriggerArea tas[] = {
 927                 TA_WHOLE, TA_WHOLE, TA_PLATFORM, TA_PLATFORM, TA_PLATFORM, TA_PLATFORM
 928         };
 929
 930         /* Get Station if it wasn't supplied */
 931         if (st == nullptr) st = Station::GetByTile(trigger_tile);
 932
 933         /* Check the cached cargo trigger bitmask to see if we need
 934          * to bother with any further processing. */
 935         if (st->cached_cargo_triggers == 0) return;
 936         if (IsValidCargoID(cargo_type) && !HasBit(st->cached_cargo_triggers, cargo_type)) return;
 937
 938         uint32_t whole_reseed = 0;
 939         ETileArea area = ETileArea(st, trigger_tile, tas[trigger]);
 940
 941         /* Bitmask of completely empty cargo types to be matched. */
 942         CargoTypes empty_mask = (trigger == SRT_CARGO_TAKEN) ? GetEmptyMask(st) : 0;
 943
 944         /* Store triggers now for var 5F */
 945         SetBit(st->waiting_triggers, trigger);
 946         uint32_t used_triggers = 0;
 947
 948         /* Check all tiles over the station to check if the specindex is still in use */
 949         for (TileIndex tile : area) {
 950                 if (st->TileBelongsToRailStation(tile)) {
 951                         const StationSpec *ss = GetStationSpec(tile);
 952                         if (ss == nullptr) continue;
 953
 954                         /* Cargo taken "will only be triggered if all of those
 955                          * cargo types have no more cargo waiting." */
 956                         if (trigger == SRT_CARGO_TAKEN) {
 957                                 if ((ss->cargo_triggers & ~empty_mask) != 0) continue;
 958                         }
 959
 960                         if (!IsValidCargoID(cargo_type) || HasBit(ss->cargo_triggers, cargo_type)) {
 961                                 StationResolverObject object(ss, st, tile, CBID_RANDOM_TRIGGER, 0);
 962                                 object.waiting_triggers = st->waiting_triggers;
 963
 964                                 const SpriteGroup *group = object.Resolve();
 965                                 if (group == nullptr) continue;
 966
 967                                 used_triggers |= object.used_triggers;
 968
 969                                 uint32_t reseed = object.GetReseedSum();
 970                                 if (reseed != 0) {
 971                                         whole_reseed |= reseed;
 972                                         reseed >>= 16;
 973
 974                                         /* Set individual tile random bits */
 975                                         uint8_t random_bits = GetStationTileRandomBits(tile);
 976                                         random_bits &= ~reseed;
 977                                         random_bits |= Random() & reseed;
 978                                         SetStationTileRandomBits(tile, random_bits);
 979
 980                                         MarkTileDirtyByTile(tile);
 981                                 }
 982                         }
 983                 }
 984         }
 985
 986         /* Update whole station random bits */
 987         st->waiting_triggers &= ~used_triggers;
 988         if ((whole_reseed & 0xFFFF) != 0) {
 989                 st->random_bits &= ~whole_reseed;
 990                 st->random_bits |= Random() & whole_reseed;
 991         }
 992 }
 993
 994 /**
 995  * Update the cached animation trigger bitmask for a station.
 996  * @param st Station to update.
 997  */
 998 void StationUpdateCachedTriggers(BaseStation *st)
 999 {
1000         st->cached_anim_triggers = 0;
1001         st->cached_cargo_triggers = 0;
1002
1003         /* Combine animation trigger bitmask for all station specs
1004          * of this station. */
1005         for (uint i = 0; i < st->speclist.size(); i++) {
1006                 const StationSpec *ss = st->speclist[i].spec;
1007                 if (ss != nullptr) {
1008                         st->cached_anim_triggers |= ss->animation.triggers;
1009                         st->cached_cargo_triggers |= ss->cargo_triggers;
1010                 }
1011         }
1012 }
1013