# newgrf_house.cpp

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    00001 /* $Id$ */
    00002
    00003 /*
    00004  * This file is part of OpenTTD.
    00005  * 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.
    00006  * 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.
    00007  * 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/>.
    00008  */
    00009
    00012 #include "stdafx.h"
    00013 #include "openttd.h"
    00014 #include "variables.h"
    00015 #include "debug.h"
    00016 #include "viewport_func.h"
    00017 #include "landscape.h"
    00018 #include "sprite.h"
    00019 #include "newgrf.h"
    00020 #include "newgrf_house.h"
    00021 #include "newgrf_spritegroup.h"
    00022 #include "newgrf_town.h"
    00023 #include "newgrf_sound.h"
    00024 #include "newgrf_commons.h"
    00025 #include "transparency.h"
    00026 #include "functions.h"
    00027 #include "company_func.h"
    00028 #include "animated_tile_func.h"
    00029 #include "company_base.h"
    00030 #include "town.h"
    00031
    00032 static BuildingCounts<uint32> _building_counts;
    00033 static HouseClassMapping _class_mapping[HOUSE_CLASS_MAX];
    00034
    00035 HouseOverrideManager _house_mngr(NEW_HOUSE_OFFSET, HOUSE_MAX, INVALID_HOUSE_ID);
    00036
    00037 HouseClassID AllocateHouseClassID(byte grf_class_id, uint32 grfid)
    00038 {
    00039   /* Start from 1 because 0 means that no class has been assigned. */
    00040   for (int i = 1; i != lengthof(_class_mapping); i++) {
    00041     HouseClassMapping *map = &_class_mapping[i];
    00042
    00043     if (map->class_id == grf_class_id && map->grfid == grfid) return (HouseClassID)i;
    00044
    00045     if (map->class_id == 0 && map->grfid == 0) {
    00046       map->class_id = grf_class_id;
    00047       map->grfid    = grfid;
    00048       return (HouseClassID)i;
    00049     }
    00050   }
    00051   return HOUSE_NO_CLASS;
    00052 }
    00053
    00054 void InitializeBuildingCounts()
    00055 {
    00056   memset(&_building_counts, 0, sizeof(_building_counts));
    00057 }
    00058
    00065 void IncreaseBuildingCount(Town *t, HouseID house_id)
    00066 {
    00067   HouseClassID class_id = HouseSpec::Get(house_id)->class_id;
    00068
    00069   if (!_loaded_newgrf_features.has_newhouses) return;
    00070
    00071   t->building_counts.id_count[house_id]++;
    00072   _building_counts.id_count[house_id]++;
    00073
    00074   if (class_id == HOUSE_NO_CLASS) return;
    00075
    00076   t->building_counts.class_count[class_id]++;
    00077   _building_counts.class_count[class_id]++;
    00078 }
    00079
    00086 void DecreaseBuildingCount(Town *t, HouseID house_id)
    00087 {
    00088   HouseClassID class_id = HouseSpec::Get(house_id)->class_id;
    00089
    00090   if (!_loaded_newgrf_features.has_newhouses) return;
    00091
    00092   if (t->building_counts.id_count[house_id] > 0) t->building_counts.id_count[house_id]--;
    00093   if (_building_counts.id_count[house_id] > 0)   _building_counts.id_count[house_id]--;
    00094
    00095   if (class_id == HOUSE_NO_CLASS) return;
    00096
    00097   if (t->building_counts.class_count[class_id] > 0) t->building_counts.class_count[class_id]--;
    00098   if (_building_counts.class_count[class_id] > 0)   _building_counts.class_count[class_id]--;
    00099 }
    00100
    00101 static uint32 HouseGetRandomBits(const ResolverObject *object)
    00102 {
    00103   const TileIndex tile = object->u.house.tile;
    00104   return (tile == INVALID_TILE || !IsTileType(tile, MP_HOUSE)) ? 0 : GetHouseRandomBits(tile);
    00105 }
    00106
    00107 static uint32 HouseGetTriggers(const ResolverObject *object)
    00108 {
    00109   const TileIndex tile = object->u.house.tile;
    00110   return (tile == INVALID_TILE || !IsTileType(tile, MP_HOUSE)) ? 0 : GetHouseTriggers(tile);
    00111 }
    00112
    00113 static void HouseSetTriggers(const ResolverObject *object, int triggers)
    00114 {
    00115   const TileIndex tile = object->u.house.tile;
    00116   if (IsTileType(tile, MP_HOUSE)) SetHouseTriggers(tile, triggers);
    00117 }
    00118
    00119 static uint32 GetNumHouses(HouseID house_id, const Town *town)
    00120 {
    00121   uint8 map_id_count, town_id_count, map_class_count, town_class_count;
    00122   HouseClassID class_id = HouseSpec::Get(house_id)->class_id;
    00123
    00124   map_id_count     = ClampU(_building_counts.id_count[house_id], 0, 255);
    00125   map_class_count  = ClampU(_building_counts.class_count[class_id], 0, 255);
    00126   town_id_count    = ClampU(town->building_counts.id_count[house_id], 0, 255);
    00127   town_class_count = ClampU(town->building_counts.class_count[class_id], 0, 255);
    00128
    00129   return map_class_count << 24 | town_class_count << 16 | map_id_count << 8 | town_id_count;
    00130 }
    00131
    00132 uint32 GetNearbyTileInformation(byte parameter, TileIndex tile)
    00133 {
    00134   tile = GetNearbyTile(parameter, tile);
    00135   return GetNearbyTileInformation(tile);
    00136 }
    00137
    00139 typedef struct {
    00140   const HouseSpec *hs;
    00141   TileIndex north_tile;
    00142 } SearchNearbyHouseData;
    00143
    00149 static bool SearchNearbyHouseID(TileIndex tile, void *user_data)
    00150 {
    00151   if (IsTileType(tile, MP_HOUSE)) {
    00152     HouseID house = GetHouseType(tile); // tile been examined
    00153     const HouseSpec *hs = HouseSpec::Get(house);
    00154     if (hs->grffile != NULL) { // must be one from a grf file
    00155       SearchNearbyHouseData *nbhd = (SearchNearbyHouseData *)user_data;
    00156
    00157       TileIndex north_tile = tile + GetHouseNorthPart(house); // modifies 'house'!
    00158       if (north_tile == nbhd->north_tile) return false; // Always ignore origin house
    00159
    00160       return hs->local_id == nbhd->hs->local_id &&  // same local id as the one requested
    00161         hs->grffile->grfid == nbhd->hs->grffile->grfid;  // from the same grf
    00162     }
    00163   }
    00164   return false;
    00165 }
    00166
    00172 static bool SearchNearbyHouseClass(TileIndex tile, void *user_data)
    00173 {
    00174   if (IsTileType(tile, MP_HOUSE)) {
    00175     HouseID house = GetHouseType(tile); // tile been examined
    00176     const HouseSpec *hs = HouseSpec::Get(house);
    00177     if (hs->grffile != NULL) { // must be one from a grf file
    00178       SearchNearbyHouseData *nbhd = (SearchNearbyHouseData *)user_data;
    00179
    00180       TileIndex north_tile = tile + GetHouseNorthPart(house); // modifies 'house'!
    00181       if (north_tile == nbhd->north_tile) return false; // Always ignore origin house
    00182
    00183       return hs->class_id == nbhd->hs->class_id &&  // same classid as the one requested
    00184         hs->grffile->grfid == nbhd->hs->grffile->grfid;  // from the same grf
    00185     }
    00186   }
    00187   return false;
    00188 }
    00189
    00195 static bool SearchNearbyHouseGRFID(TileIndex tile, void *user_data)
    00196 {
    00197   if (IsTileType(tile, MP_HOUSE)) {
    00198     HouseID house = GetHouseType(tile); // tile been examined
    00199     const HouseSpec *hs = HouseSpec::Get(house);
    00200     if (hs->grffile != NULL) { // must be one from a grf file
    00201       SearchNearbyHouseData *nbhd = (SearchNearbyHouseData *)user_data;
    00202
    00203       TileIndex north_tile = tile + GetHouseNorthPart(house); // modifies 'house'!
    00204       if (north_tile == nbhd->north_tile) return false; // Always ignore origin house
    00205
    00206       return hs->grffile->grfid == nbhd->hs->grffile->grfid;  // from the same grf
    00207     }
    00208   }
    00209   return false;
    00210 }
    00211
    00221 static uint32 GetDistanceFromNearbyHouse(uint8 parameter, TileIndex tile, HouseID house)
    00222 {
    00223   static TestTileOnSearchProc * const search_procs[3] = {
    00224     SearchNearbyHouseID,
    00225     SearchNearbyHouseClass,
    00226     SearchNearbyHouseGRFID,
    00227   };
    00228   TileIndex found_tile = tile;
    00229   uint8 searchtype = GB(parameter, 6, 2);
    00230   uint8 searchradius = GB(parameter, 0, 6);
    00231   if (searchtype >= lengthof(search_procs)) return 0;  // do not run on ill-defined code
    00232   if (searchradius < 1) return 0; // do not use a too low radius
    00233
    00234   SearchNearbyHouseData nbhd;
    00235   nbhd.hs = HouseSpec::Get(house);
    00236   nbhd.north_tile = tile + GetHouseNorthPart(house); // modifies 'house'!
    00237
    00238   /* Use a pointer for the tile to start the search. Will be required for calculating the distance*/
    00239   if (CircularTileSearch(&found_tile, 2 * searchradius + 1, search_procs[searchtype], &nbhd)) {
    00240     return DistanceManhattan(found_tile, tile);
    00241   }
    00242   return 0;
    00243 }
    00244
    00250 static uint32 HouseGetVariable(const ResolverObject *object, byte variable, byte parameter, bool *available)
    00251 {
    00252   const Town *town = object->u.house.town;
    00253   TileIndex tile   = object->u.house.tile;
    00254   HouseID house_id = object->u.house.house_id;
    00255
    00256   if (object->scope == VSG_SCOPE_PARENT) {
    00257     return TownGetVariable(variable, parameter, available, town);
    00258   }
    00259
    00260   switch (variable) {
    00261     /* Construction stage. */
    00262     case 0x40: return (IsTileType(tile, MP_HOUSE) ? GetHouseBuildingStage(tile) : 0) | TileHash2Bit(TileX(tile), TileY(tile)) << 2;
    00263
    00264     /* Building age. */
    00265     case 0x41: return IsTileType(tile, MP_HOUSE) ? GetHouseAge(tile) : 0;
    00266
    00267     /* Town zone */
    00268     case 0x42: return GetTownRadiusGroup(town, tile);
    00269
    00270     /* Terrain type */
    00271     case 0x43: return GetTerrainType(tile);
    00272
    00273     /* Number of this type of building on the map. */
    00274     case 0x44: return GetNumHouses(house_id, town);
    00275
    00276     /* Whether the town is being created or just expanded. */
    00277     case 0x45: return _generating_world ? 1 : 0;
    00278
    00279     /* Current animation frame. */
    00280     case 0x46: return IsTileType(tile, MP_HOUSE) ? GetHouseAnimationFrame(tile) : 0;
    00281
    00282     /* Position of the house */
    00283     case 0x47: return TileY(tile) << 16 | TileX(tile);
    00284
    00285     /* Building counts for old houses with id = parameter. */
    00286     case 0x60: return GetNumHouses(parameter, town);
    00287
    00288     /* Building counts for new houses with id = parameter. */
    00289     case 0x61: {
    00290       const HouseSpec *hs = HouseSpec::Get(house_id);
    00291       if (hs->grffile == NULL) return 0;
    00292
    00293       HouseID new_house = _house_mngr.GetID(parameter, hs->grffile->grfid);
    00294       return new_house == INVALID_HOUSE_ID ? 0 : GetNumHouses(new_house, town);
    00295     }
    00296
    00297     /* Land info for nearby tiles. */
    00298     case 0x62: return GetNearbyTileInformation(parameter, tile);
    00299
    00300     /* Current animation frame of nearby house tiles */
    00301     case 0x63: {
    00302       TileIndex testtile = GetNearbyTile(parameter, tile);
    00303       return IsTileType(testtile, MP_HOUSE) ? GetHouseAnimationFrame(testtile) : 0;
    00304     }
    00305
    00306     /* Cargo acceptance history of nearby stations */
    00307     /*case 0x64: not implemented yet */
    00308
    00309     /* Distance test for some house types */
    00310     case 0x65: return GetDistanceFromNearbyHouse(parameter, tile, object->u.house.house_id);
    00311   }
    00312
    00313   DEBUG(grf, 1, "Unhandled house property 0x%X", variable);
    00314
    00315   *available = false;
    00316   return UINT_MAX;
    00317 }
    00318
    00319 static const SpriteGroup *HouseResolveReal(const ResolverObject *object, const RealSpriteGroup *group)
    00320 {
    00321   /* Houses do not have 'real' groups */
    00322   return NULL;
    00323 }
    00324
    00330 static void NewHouseResolver(ResolverObject *res, HouseID house_id, TileIndex tile, Town *town)
    00331 {
    00332   res->GetRandomBits = HouseGetRandomBits;
    00333   res->GetTriggers   = HouseGetTriggers;
    00334   res->SetTriggers   = HouseSetTriggers;
    00335   res->GetVariable   = HouseGetVariable;
    00336   res->ResolveReal   = HouseResolveReal;
    00337
    00338   res->u.house.tile     = tile;
    00339   res->u.house.town     = town;
    00340   res->u.house.house_id = house_id;
    00341
    00342   res->callback        = CBID_NO_CALLBACK;
    00343   res->callback_param1 = 0;
    00344   res->callback_param2 = 0;
    00345   res->last_value      = 0;
    00346   res->trigger         = 0;
    00347   res->reseed          = 0;
    00348   res->count           = 0;
    00349
    00350   const HouseSpec *hs = HouseSpec::Get(house_id);
    00351   res->grffile         = (hs != NULL ? hs->grffile : NULL);
    00352 }
    00353
    00354 uint16 GetHouseCallback(CallbackID callback, uint32 param1, uint32 param2, HouseID house_id, Town *town, TileIndex tile)
    00355 {
    00356   ResolverObject object;
    00357   const SpriteGroup *group;
    00358
    00359   NewHouseResolver(&object, house_id, tile, town);
    00360   object.callback = callback;
    00361   object.callback_param1 = param1;
    00362   object.callback_param2 = param2;
    00363
    00364   group = SpriteGroup::Resolve(HouseSpec::Get(house_id)->spritegroup, &object);
    00365   if (group == NULL) return CALLBACK_FAILED;
    00366
    00367   return group->GetCallbackResult();
    00368 }
    00369
    00370 static void DrawTileLayout(const TileInfo *ti, const TileLayoutSpriteGroup *group, byte stage, HouseID house_id)
    00371 {
    00372   const DrawTileSprites *dts = group->dts;
    00373   const DrawTileSeqStruct *dtss;
    00374
    00375   const HouseSpec *hs = HouseSpec::Get(house_id);
    00376   SpriteID palette = hs->random_colour[TileHash2Bit(ti->x, ti->y)] + PALETTE_RECOLOUR_START;
    00377   if (HasBit(hs->callback_mask, CBM_HOUSE_COLOUR)) {
    00378     uint16 callback = GetHouseCallback(CBID_HOUSE_COLOUR, 0, 0, house_id, Town::GetByTile(ti->tile), ti->tile);
    00379     if (callback != CALLBACK_FAILED) {
    00380       /* If bit 14 is set, we should use a 2cc colour map, else use the callback value. */
    00381       palette = HasBit(callback, 14) ? GB(callback, 0, 8) + SPR_2CCMAP_BASE : callback;
    00382     }
    00383   }
    00384
    00385   SpriteID image = dts->ground.sprite;
    00386   SpriteID pal   = dts->ground.pal;
    00387
    00388   if (IS_CUSTOM_SPRITE(image)) image += stage;
    00389
    00390   if (GB(image, 0, SPRITE_WIDTH) != 0) {
    00391     DrawGroundSprite(image, GroundSpritePaletteTransform(image, pal, palette));
    00392   }
    00393
    00394   foreach_draw_tile_seq(dtss, dts->seq) {
    00395     if (GB(dtss->image.sprite, 0, SPRITE_WIDTH) == 0) continue;
    00396
    00397     image = dtss->image.sprite;
    00398     pal   = dtss->image.pal;
    00399
    00400     /* Stop drawing sprite sequence once we meet a sprite that doesn't have to be opaque */
    00401     if (IsInvisibilitySet(TO_HOUSES) && !HasBit(image, SPRITE_MODIFIER_OPAQUE)) return;
    00402
    00403     if (IS_CUSTOM_SPRITE(image)) image += stage;
    00404
    00405     pal = SpriteLayoutPaletteTransform(image, pal, palette);
    00406
    00407     if ((byte)dtss->delta_z != 0x80) {
    00408       AddSortableSpriteToDraw(
    00409         image, pal,
    00410         ti->x + dtss->delta_x, ti->y + dtss->delta_y,
    00411         dtss->size_x, dtss->size_y,
    00412         dtss->size_z, ti->z + dtss->delta_z,
    00413         !HasBit(image, SPRITE_MODIFIER_OPAQUE) && IsTransparencySet(TO_HOUSES)
    00414       );
    00415     } else {
    00416       /* For industries and houses delta_x and delta_y are unsigned */
    00417       AddChildSpriteScreen(image, pal, (byte)dtss->delta_x, (byte)dtss->delta_y, !HasBit(image, SPRITE_MODIFIER_OPAQUE) && IsTransparencySet(TO_HOUSES));
    00418     }
    00419   }
    00420 }
    00421
    00422 void DrawNewHouseTile(TileInfo *ti, HouseID house_id)
    00423 {
    00424   const HouseSpec *hs = HouseSpec::Get(house_id);
    00425   const SpriteGroup *group;
    00426   ResolverObject object;
    00427
    00428   if (ti->tileh != SLOPE_FLAT) {
    00429     bool draw_old_one = true;
    00430     if (HasBit(hs->callback_mask, CBM_HOUSE_DRAW_FOUNDATIONS)) {
    00431       /* Called to determine the type (if any) of foundation to draw for the house tile */
    00432       uint32 callback_res = GetHouseCallback(CBID_HOUSE_DRAW_FOUNDATIONS, 0, 0, house_id, Town::GetByTile(ti->tile), ti->tile);
    00433       draw_old_one = (callback_res != 0);
    00434     }
    00435
    00436     if (draw_old_one) DrawFoundation(ti, FOUNDATION_LEVELED);
    00437   }
    00438
    00439   NewHouseResolver(&object, house_id, ti->tile, Town::GetByTile(ti->tile));
    00440
    00441   group = SpriteGroup::Resolve(hs->spritegroup, &object);
    00442   const TileLayoutSpriteGroup *tlgroup = (const TileLayoutSpriteGroup *)group;
    00443   if (group == NULL || group->type != SGT_TILELAYOUT || tlgroup->num_building_stages == 0) {
    00444     return;
    00445   } else {
    00446     /* Limit the building stage to the number of stages supplied. */
    00447     byte stage = GetHouseBuildingStage(ti->tile);
    00448     stage = Clamp(stage - 4 + tlgroup->num_building_stages, 0, tlgroup->num_building_stages - 1);
    00449     DrawTileLayout(ti, tlgroup, stage, house_id);
    00450   }
    00451 }
    00452
    00453 void AnimateNewHouseTile(TileIndex tile)
    00454 {
    00455   const HouseSpec *hs = HouseSpec::Get(GetHouseType(tile));
    00456   byte animation_speed = hs->animation_speed;
    00457   bool frame_set_by_callback = false;
    00458
    00459   if (HasBit(hs->callback_mask, CBM_HOUSE_ANIMATION_SPEED)) {
    00460     uint16 callback_res = GetHouseCallback(CBID_HOUSE_ANIMATION_SPEED, 0, 0, GetHouseType(tile), Town::GetByTile(tile), tile);
    00461     if (callback_res != CALLBACK_FAILED) animation_speed = Clamp(callback_res & 0xFF, 2, 16);
    00462   }
    00463
    00464   /* An animation speed of 2 means the animation frame changes 4 ticks, and
    00465    * increasing this value by one doubles the wait. 2 is the minimum value
    00466    * allowed for animation_speed, which corresponds to 120ms, and 16 is the
    00467    * maximum, corresponding to around 33 minutes. */
    00468   if (_tick_counter % (1 << animation_speed) != 0) return;
    00469
    00470   byte frame      = GetHouseAnimationFrame(tile);
    00471   byte num_frames = GB(hs->animation_frames, 0, 7);
    00472
    00473   if (HasBit(hs->callback_mask, CBM_HOUSE_ANIMATION_NEXT_FRAME)) {
    00474     uint32 param = (hs->extra_flags & CALLBACK_1A_RANDOM_BITS) ? Random() : 0;
    00475     uint16 callback_res = GetHouseCallback(CBID_HOUSE_ANIMATION_NEXT_FRAME, param, 0, GetHouseType(tile), Town::GetByTile(tile), tile);
    00476
    00477     if (callback_res != CALLBACK_FAILED) {
    00478       frame_set_by_callback = true;
    00479
    00480       switch (callback_res & 0xFF) {
    00481         case 0xFF:
    00482           DeleteAnimatedTile(tile);
    00483           break;
    00484         case 0xFE:
    00485           /* Carry on as normal. */
    00486           frame_set_by_callback = false;
    00487           break;
    00488         default:
    00489           frame = callback_res & 0xFF;
    00490           break;
    00491       }
    00492
    00493       /* If the lower 7 bits of the upper byte of the callback
    00494        * result are not empty, it is a sound effect. */
    00495       if (GB(callback_res, 8, 7) != 0) PlayTileSound(hs->grffile, GB(callback_res, 8, 7), tile);
    00496     }
    00497   }
    00498
    00499   if (!frame_set_by_callback) {
    00500     if (frame < num_frames) {
    00501       frame++;
    00502     } else if (frame == num_frames && HasBit(hs->animation_frames, 7)) {
    00503       /* This animation loops, so start again from the beginning */
    00504       frame = 0;
    00505     } else {
    00506       /* This animation doesn't loop, so stay here */
    00507       DeleteAnimatedTile(tile);
    00508     }
    00509   }
    00510
    00511   SetHouseAnimationFrame(tile, frame);
    00512   MarkTileDirtyByTile(tile);
    00513 }
    00514
    00515 void ChangeHouseAnimationFrame(const GRFFile *file, TileIndex tile, uint16 callback_result)
    00516 {
    00517   switch (callback_result & 0xFF) {
    00518     case 0xFD: /* Do nothing. */         break;
    00519     case 0xFE: AddAnimatedTile(tile);    break;
    00520     case 0xFF: DeleteAnimatedTile(tile); break;
    00521     default:
    00522       SetHouseAnimationFrame(tile, callback_result & 0xFF);
    00523       AddAnimatedTile(tile);
    00524       break;
    00525   }
    00526   /* If the lower 7 bits of the upper byte of the callback
    00527    * result are not empty, it is a sound effect. */
    00528   if (GB(callback_result, 8, 7) != 0) PlayTileSound(file, GB(callback_result, 8, 7), tile);
    00529 }
    00530
    00531 bool CanDeleteHouse(TileIndex tile)
    00532 {
    00533   const HouseSpec *hs = HouseSpec::Get(GetHouseType(tile));
    00534
    00535   /* Humans are always allowed to remove buildings, as is water and
    00536    * anyone using the scenario editor. */
    00537   if (Company::IsValidHumanID(_current_company) || _current_company == OWNER_WATER || _current_company == OWNER_NONE) {
    00538     return true;
    00539   }
    00540
    00541   if (HasBit(hs->callback_mask, CBM_HOUSE_DENY_DESTRUCTION)) {
    00542     uint16 callback_res = GetHouseCallback(CBID_HOUSE_DENY_DESTRUCTION, 0, 0, GetHouseType(tile), Town::GetByTile(tile), tile);
    00543     return (callback_res == CALLBACK_FAILED || callback_res == 0);
    00544   } else {
    00545     return !(hs->extra_flags & BUILDING_IS_PROTECTED);
    00546   }
    00547 }
    00548
    00549 static void AnimationControl(TileIndex tile, uint16 random_bits)
    00550 {
    00551   const HouseSpec *hs = HouseSpec::Get(GetHouseType(tile));
    00552
    00553   if (HasBit(hs->callback_mask, CBM_HOUSE_ANIMATION_START_STOP)) {
    00554     uint32 param = (hs->extra_flags & SYNCHRONISED_CALLBACK_1B) ? (GB(Random(), 0, 16) | random_bits << 16) : Random();
    00555     uint16 callback_res = GetHouseCallback(CBID_HOUSE_ANIMATION_START_STOP, param, 0, GetHouseType(tile), Town::GetByTile(tile), tile);
    00556
    00557     if (callback_res != CALLBACK_FAILED) ChangeHouseAnimationFrame(hs->grffile, tile, callback_res);
    00558   }
    00559 }
    00560
    00561 bool NewHouseTileLoop(TileIndex tile)
    00562 {
    00563   const HouseSpec *hs = HouseSpec::Get(GetHouseType(tile));
    00564
    00565   if (GetHouseProcessingTime(tile) > 0) {
    00566     DecHouseProcessingTime(tile);
    00567     return true;
    00568   }
    00569
    00570   TriggerHouse(tile, HOUSE_TRIGGER_TILE_LOOP);
    00571   if (hs->building_flags & BUILDING_HAS_1_TILE) TriggerHouse(tile, HOUSE_TRIGGER_TILE_LOOP_TOP);
    00572
    00573   if (HasBit(hs->callback_mask, CBM_HOUSE_ANIMATION_START_STOP)) {
    00574     /* If this house is marked as having a synchronised callback, all the
    00575      * tiles will have the callback called at once, rather than when the
    00576      * tile loop reaches them. This should only be enabled for the northern
    00577      * tile, or strange things will happen (here, and in TTDPatch). */
    00578     if (hs->extra_flags & SYNCHRONISED_CALLBACK_1B) {
    00579       uint16 random = GB(Random(), 0, 16);
    00580
    00581       if (hs->building_flags & BUILDING_HAS_1_TILE)  AnimationControl(tile, random);
    00582       if (hs->building_flags & BUILDING_2_TILES_Y)   AnimationControl(TILE_ADDXY(tile, 0, 1), random);
    00583       if (hs->building_flags & BUILDING_2_TILES_X)   AnimationControl(TILE_ADDXY(tile, 1, 0), random);
    00584       if (hs->building_flags & BUILDING_HAS_4_TILES) AnimationControl(TILE_ADDXY(tile, 1, 1), random);
    00585     } else {
    00586       AnimationControl(tile, 0);
    00587     }
    00588   }
    00589
    00590   /* Check callback 21, which determines if a house should be destroyed. */
    00591   if (HasBit(hs->callback_mask, CBM_HOUSE_DESTRUCTION)) {
    00592     uint16 callback_res = GetHouseCallback(CBID_HOUSE_DESTRUCTION, 0, 0, GetHouseType(tile), Town::GetByTile(tile), tile);
    00593     if (callback_res != CALLBACK_FAILED && GB(callback_res, 0, 8) > 0) {
    00594       ClearTownHouse(Town::GetByTile(tile), tile);
    00595       return false;
    00596     }
    00597   }
    00598
    00599   SetHouseProcessingTime(tile, hs->processing_time);
    00600   MarkTileDirtyByTile(tile);
    00601   return true;
    00602 }
    00603
    00604 static void DoTriggerHouse(TileIndex tile, HouseTrigger trigger, byte base_random, bool first)
    00605 {
    00606   ResolverObject object;
    00607
    00608   /* We can't trigger a non-existent building... */
    00609   assert(IsTileType(tile, MP_HOUSE));
    00610
    00611   HouseID hid = GetHouseType(tile);
    00612   HouseSpec *hs = HouseSpec::Get(hid);
    00613
    00614   if (hs->spritegroup == NULL) return;
    00615
    00616   NewHouseResolver(&object, hid, tile, Town::GetByTile(tile));
    00617
    00618   object.callback = CBID_RANDOM_TRIGGER;
    00619   object.trigger = trigger;
    00620
    00621   const SpriteGroup *group = SpriteGroup::Resolve(hs->spritegroup, &object);
    00622   if (group == NULL) return;
    00623
    00624   byte new_random_bits = Random();
    00625   byte random_bits = GetHouseRandomBits(tile);
    00626   random_bits &= ~object.reseed;
    00627   random_bits |= (first ? new_random_bits : base_random) & object.reseed;
    00628   SetHouseRandomBits(tile, random_bits);
    00629
    00630   switch (trigger) {
    00631     case HOUSE_TRIGGER_TILE_LOOP:
    00632       /* Random value already set. */
    00633       break;
    00634
    00635     case HOUSE_TRIGGER_TILE_LOOP_TOP:
    00636       if (!first) {
    00637         /* The top tile is marked dirty by the usual TileLoop */
    00638         MarkTileDirtyByTile(tile);
    00639         break;
    00640       }
    00641       /* Random value of first tile already set. */
    00642       if (hs->building_flags & BUILDING_2_TILES_Y)   DoTriggerHouse(TILE_ADDXY(tile, 0, 1), trigger, random_bits, false);
    00643       if (hs->building_flags & BUILDING_2_TILES_X)   DoTriggerHouse(TILE_ADDXY(tile, 1, 0), trigger, random_bits, false);
    00644       if (hs->building_flags & BUILDING_HAS_4_TILES) DoTriggerHouse(TILE_ADDXY(tile, 1, 1), trigger, random_bits, false);
    00645       break;
    00646   }
    00647 }
    00648
    00649 void TriggerHouse(TileIndex t, HouseTrigger trigger)
    00650 {
    00651   DoTriggerHouse(t, trigger, 0, true);
    00652 }