tunnelbridge_cmd.cpp

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00001 /* $Id: tunnelbridge_cmd.cpp 26277 2014-01-26 13:50:10Z frosch $ */
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 
00016 #include "stdafx.h"
00017 #include "newgrf_object.h"
00018 #include "viewport_func.h"
00019 #include "cmd_helper.h"
00020 #include "command_func.h"
00021 #include "town.h"
00022 #include "train.h"
00023 #include "ship.h"
00024 #include "roadveh.h"
00025 #include "pathfinder/yapf/yapf_cache.h"
00026 #include "newgrf_sound.h"
00027 #include "autoslope.h"
00028 #include "tunnelbridge_map.h"
00029 #include "strings_func.h"
00030 #include "date_func.h"
00031 #include "clear_func.h"
00032 #include "vehicle_func.h"
00033 #include "sound_func.h"
00034 #include "tunnelbridge.h"
00035 #include "cheat_type.h"
00036 #include "elrail_func.h"
00037 #include "pbs.h"
00038 #include "company_base.h"
00039 #include "newgrf_railtype.h"
00040 #include "object_base.h"
00041 #include "water.h"
00042 #include "company_gui.h"
00043 
00044 #include "table/strings.h"
00045 #include "table/bridge_land.h"
00046 
00047 BridgeSpec _bridge[MAX_BRIDGES]; 
00048 TileIndex _build_tunnel_endtile; 
00049 
00051 static const int BRIDGE_Z_START = 3;
00052 
00054 void ResetBridges()
00055 {
00056   /* First, free sprite table data */
00057   for (BridgeType i = 0; i < MAX_BRIDGES; i++) {
00058     if (_bridge[i].sprite_table != NULL) {
00059       for (BridgePieces j = BRIDGE_PIECE_NORTH; j < BRIDGE_PIECE_INVALID; j++) free(_bridge[i].sprite_table[j]);
00060       free(_bridge[i].sprite_table);
00061     }
00062   }
00063 
00064   /* Then, wipe out current bridges */
00065   memset(&_bridge, 0, sizeof(_bridge));
00066   /* And finally, reinstall default data */
00067   memcpy(&_bridge, &_orig_bridge, sizeof(_orig_bridge));
00068 }
00069 
00076 int CalcBridgeLenCostFactor(int length)
00077 {
00078   if (length < 2) return length;
00079 
00080   length -= 2;
00081   int sum = 2;
00082   for (int delta = 1;; delta++) {
00083     for (int count = 0; count < delta; count++) {
00084       if (length == 0) return sum;
00085       sum += delta;
00086       length--;
00087     }
00088   }
00089 }
00090 
00097 Foundation GetBridgeFoundation(Slope tileh, Axis axis)
00098 {
00099   if (tileh == SLOPE_FLAT ||
00100       ((tileh == SLOPE_NE || tileh == SLOPE_SW) && axis == AXIS_X) ||
00101       ((tileh == SLOPE_NW || tileh == SLOPE_SE) && axis == AXIS_Y)) return FOUNDATION_NONE;
00102 
00103   return (HasSlopeHighestCorner(tileh) ? InclinedFoundation(axis) : FlatteningFoundation(tileh));
00104 }
00105 
00113 bool HasBridgeFlatRamp(Slope tileh, Axis axis)
00114 {
00115   ApplyFoundationToSlope(GetBridgeFoundation(tileh, axis), &tileh);
00116   /* If the foundation slope is flat the bridge has a non-flat ramp and vice versa. */
00117   return (tileh != SLOPE_FLAT);
00118 }
00119 
00120 static inline const PalSpriteID *GetBridgeSpriteTable(int index, BridgePieces table)
00121 {
00122   const BridgeSpec *bridge = GetBridgeSpec(index);
00123   assert(table < BRIDGE_PIECE_INVALID);
00124   if (bridge->sprite_table == NULL || bridge->sprite_table[table] == NULL) {
00125     return _bridge_sprite_table[index][table];
00126   } else {
00127     return bridge->sprite_table[table];
00128   }
00129 }
00130 
00131 
00140 static CommandCost CheckBridgeSlopeNorth(Axis axis, Slope *tileh, int *z)
00141 {
00142   Foundation f = GetBridgeFoundation(*tileh, axis);
00143   *z += ApplyFoundationToSlope(f, tileh);
00144 
00145   Slope valid_inclined = (axis == AXIS_X ? SLOPE_NE : SLOPE_NW);
00146   if ((*tileh != SLOPE_FLAT) && (*tileh != valid_inclined)) return CMD_ERROR;
00147 
00148   if (f == FOUNDATION_NONE) return CommandCost();
00149 
00150   return CommandCost(EXPENSES_CONSTRUCTION, _price[PR_BUILD_FOUNDATION]);
00151 }
00152 
00161 static CommandCost CheckBridgeSlopeSouth(Axis axis, Slope *tileh, int *z)
00162 {
00163   Foundation f = GetBridgeFoundation(*tileh, axis);
00164   *z += ApplyFoundationToSlope(f, tileh);
00165 
00166   Slope valid_inclined = (axis == AXIS_X ? SLOPE_SW : SLOPE_SE);
00167   if ((*tileh != SLOPE_FLAT) && (*tileh != valid_inclined)) return CMD_ERROR;
00168 
00169   if (f == FOUNDATION_NONE) return CommandCost();
00170 
00171   return CommandCost(EXPENSES_CONSTRUCTION, _price[PR_BUILD_FOUNDATION]);
00172 }
00173 
00180 CommandCost CheckBridgeAvailability(BridgeType bridge_type, uint bridge_len, DoCommandFlag flags)
00181 {
00182   if (flags & DC_QUERY_COST) {
00183     if (bridge_len <= _settings_game.construction.max_bridge_length) return CommandCost();
00184     return_cmd_error(STR_ERROR_BRIDGE_TOO_LONG);
00185   }
00186 
00187   if (bridge_type >= MAX_BRIDGES) return CMD_ERROR;
00188 
00189   const BridgeSpec *b = GetBridgeSpec(bridge_type);
00190   if (b->avail_year > _cur_year) return CMD_ERROR;
00191 
00192   uint max = min(b->max_length, _settings_game.construction.max_bridge_length);
00193 
00194   if (b->min_length > bridge_len) return CMD_ERROR;
00195   if (bridge_len <= max) return CommandCost();
00196   return_cmd_error(STR_ERROR_BRIDGE_TOO_LONG);
00197 }
00198 
00211 CommandCost CmdBuildBridge(TileIndex end_tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
00212 {
00213   CompanyID company = _current_company;
00214 
00215   RailType railtype = INVALID_RAILTYPE;
00216   RoadTypes roadtypes = ROADTYPES_NONE;
00217 
00218   /* unpack parameters */
00219   BridgeType bridge_type = GB(p2, 0, 8);
00220 
00221   if (!IsValidTile(p1)) return_cmd_error(STR_ERROR_BRIDGE_THROUGH_MAP_BORDER);
00222 
00223   TransportType transport_type = Extract<TransportType, 15, 2>(p2);
00224 
00225   /* type of bridge */
00226   switch (transport_type) {
00227     case TRANSPORT_ROAD:
00228       roadtypes = Extract<RoadTypes, 8, 2>(p2);
00229       if (!HasExactlyOneBit(roadtypes) || !HasRoadTypesAvail(company, roadtypes)) return CMD_ERROR;
00230       break;
00231 
00232     case TRANSPORT_RAIL:
00233       railtype = Extract<RailType, 8, 4>(p2);
00234       if (!ValParamRailtype(railtype)) return CMD_ERROR;
00235       break;
00236 
00237     case TRANSPORT_WATER:
00238       break;
00239 
00240     default:
00241       /* Airports don't have bridges. */
00242       return CMD_ERROR;
00243   }
00244   TileIndex tile_start = p1;
00245   TileIndex tile_end = end_tile;
00246 
00247   if (company == OWNER_DEITY) {
00248     if (transport_type != TRANSPORT_ROAD) return CMD_ERROR;
00249     const Town *town = CalcClosestTownFromTile(tile_start);
00250 
00251     company = OWNER_TOWN;
00252 
00253     /* If we are not within a town, we are not owned by the town */
00254     if (town == NULL || DistanceSquare(tile_start, town->xy) > town->cache.squared_town_zone_radius[HZB_TOWN_EDGE]) {
00255       company = OWNER_NONE;
00256     }
00257   }
00258 
00259   if (tile_start == tile_end) {
00260     return_cmd_error(STR_ERROR_CAN_T_START_AND_END_ON);
00261   }
00262 
00263   Axis direction;
00264   if (TileX(tile_start) == TileX(tile_end)) {
00265     direction = AXIS_Y;
00266   } else if (TileY(tile_start) == TileY(tile_end)) {
00267     direction = AXIS_X;
00268   } else {
00269     return_cmd_error(STR_ERROR_START_AND_END_MUST_BE_IN);
00270   }
00271 
00272   if (tile_end < tile_start) Swap(tile_start, tile_end);
00273 
00274   uint bridge_len = GetTunnelBridgeLength(tile_start, tile_end);
00275   if (transport_type != TRANSPORT_WATER) {
00276     /* set and test bridge length, availability */
00277     CommandCost ret = CheckBridgeAvailability(bridge_type, bridge_len, flags);
00278     if (ret.Failed()) return ret;
00279   } else {
00280     if (bridge_len > _settings_game.construction.max_bridge_length) return_cmd_error(STR_ERROR_BRIDGE_TOO_LONG);
00281   }
00282 
00283   int z_start;
00284   int z_end;
00285   Slope tileh_start = GetTileSlope(tile_start, &z_start);
00286   Slope tileh_end = GetTileSlope(tile_end, &z_end);
00287   bool pbs_reservation = false;
00288 
00289   CommandCost terraform_cost_north = CheckBridgeSlopeNorth(direction, &tileh_start, &z_start);
00290   CommandCost terraform_cost_south = CheckBridgeSlopeSouth(direction, &tileh_end,   &z_end);
00291 
00292   /* Aqueducts can't be built of flat land. */
00293   if (transport_type == TRANSPORT_WATER && (tileh_start == SLOPE_FLAT || tileh_end == SLOPE_FLAT)) return_cmd_error(STR_ERROR_LAND_SLOPED_IN_WRONG_DIRECTION);
00294   if (z_start != z_end) return_cmd_error(STR_ERROR_BRIDGEHEADS_NOT_SAME_HEIGHT);
00295 
00296   CommandCost cost(EXPENSES_CONSTRUCTION);
00297   Owner owner;
00298   bool is_new_owner;
00299   if (IsBridgeTile(tile_start) && IsBridgeTile(tile_end) &&
00300       GetOtherBridgeEnd(tile_start) == tile_end &&
00301       GetTunnelBridgeTransportType(tile_start) == transport_type) {
00302     /* Replace a current bridge. */
00303 
00304     /* If this is a railway bridge, make sure the railtypes match. */
00305     if (transport_type == TRANSPORT_RAIL && GetRailType(tile_start) != railtype) {
00306       return_cmd_error(STR_ERROR_MUST_DEMOLISH_BRIDGE_FIRST);
00307     }
00308 
00309     /* Do not replace town bridges with lower speed bridges, unless in scenario editor. */
00310     if (!(flags & DC_QUERY_COST) && IsTileOwner(tile_start, OWNER_TOWN) &&
00311         GetBridgeSpec(bridge_type)->speed < GetBridgeSpec(GetBridgeType(tile_start))->speed &&
00312         _game_mode != GM_EDITOR) {
00313       Town *t = ClosestTownFromTile(tile_start, UINT_MAX);
00314 
00315       if (t == NULL) {
00316         return CMD_ERROR;
00317       } else {
00318         SetDParam(0, t->index);
00319         return_cmd_error(STR_ERROR_LOCAL_AUTHORITY_REFUSES_TO_ALLOW_THIS);
00320       }
00321     }
00322 
00323     /* Do not replace the bridge with the same bridge type. */
00324     if (!(flags & DC_QUERY_COST) && (bridge_type == GetBridgeType(tile_start)) && (transport_type != TRANSPORT_ROAD || (roadtypes & ~GetRoadTypes(tile_start)) == 0)) {
00325       return_cmd_error(STR_ERROR_ALREADY_BUILT);
00326     }
00327 
00328     /* Do not allow replacing another company's bridges. */
00329     if (!IsTileOwner(tile_start, company) && !IsTileOwner(tile_start, OWNER_TOWN) && !IsTileOwner(tile_start, OWNER_NONE)) {
00330       return_cmd_error(STR_ERROR_AREA_IS_OWNED_BY_ANOTHER);
00331     }
00332 
00333     cost.AddCost((bridge_len + 1) * _price[PR_CLEAR_BRIDGE]); // The cost of clearing the current bridge.
00334     owner = GetTileOwner(tile_start);
00335 
00336     /* If bridge belonged to bankrupt company, it has a new owner now */
00337     is_new_owner = (owner == OWNER_NONE);
00338     if (is_new_owner) owner = company;
00339 
00340     switch (transport_type) {
00341       case TRANSPORT_RAIL:
00342         /* Keep the reservation, the path stays valid. */
00343         pbs_reservation = HasTunnelBridgeReservation(tile_start);
00344         break;
00345 
00346       case TRANSPORT_ROAD:
00347         /* Do not remove road types when upgrading a bridge */
00348         roadtypes |= GetRoadTypes(tile_start);
00349         break;
00350 
00351       default: break;
00352     }
00353   } else {
00354     /* Build a new bridge. */
00355 
00356     bool allow_on_slopes = (_settings_game.construction.build_on_slopes && transport_type != TRANSPORT_WATER);
00357 
00358     /* Try and clear the start landscape */
00359     CommandCost ret = DoCommand(tile_start, 0, 0, flags, CMD_LANDSCAPE_CLEAR);
00360     if (ret.Failed()) return ret;
00361     cost = ret;
00362 
00363     if (terraform_cost_north.Failed() || (terraform_cost_north.GetCost() != 0 && !allow_on_slopes)) return_cmd_error(STR_ERROR_LAND_SLOPED_IN_WRONG_DIRECTION);
00364     cost.AddCost(terraform_cost_north);
00365 
00366     /* Try and clear the end landscape */
00367     ret = DoCommand(tile_end, 0, 0, flags, CMD_LANDSCAPE_CLEAR);
00368     if (ret.Failed()) return ret;
00369     cost.AddCost(ret);
00370 
00371     /* false - end tile slope check */
00372     if (terraform_cost_south.Failed() || (terraform_cost_south.GetCost() != 0 && !allow_on_slopes)) return_cmd_error(STR_ERROR_LAND_SLOPED_IN_WRONG_DIRECTION);
00373     cost.AddCost(terraform_cost_south);
00374 
00375     const TileIndex heads[] = {tile_start, tile_end};
00376     for (int i = 0; i < 2; i++) {
00377       if (MayHaveBridgeAbove(heads[i])) {
00378         if (IsBridgeAbove(heads[i])) {
00379           TileIndex north_head = GetNorthernBridgeEnd(heads[i]);
00380 
00381           if (direction == GetBridgeAxis(heads[i])) return_cmd_error(STR_ERROR_MUST_DEMOLISH_BRIDGE_FIRST);
00382 
00383           if (z_start + 1 == GetBridgeHeight(north_head)) {
00384             return_cmd_error(STR_ERROR_MUST_DEMOLISH_BRIDGE_FIRST);
00385           }
00386         }
00387       }
00388     }
00389 
00390     TileIndexDiff delta = (direction == AXIS_X ? TileDiffXY(1, 0) : TileDiffXY(0, 1));
00391     for (TileIndex tile = tile_start + delta; tile != tile_end; tile += delta) {
00392       if (GetTileMaxZ(tile) > z_start) return_cmd_error(STR_ERROR_BRIDGE_TOO_LOW_FOR_TERRAIN);
00393 
00394       if (MayHaveBridgeAbove(tile) && IsBridgeAbove(tile)) {
00395         /* Disallow crossing bridges for the time being */
00396         return_cmd_error(STR_ERROR_MUST_DEMOLISH_BRIDGE_FIRST);
00397       }
00398 
00399       switch (GetTileType(tile)) {
00400         case MP_WATER:
00401           if (!IsWater(tile) && !IsCoast(tile)) goto not_valid_below;
00402           break;
00403 
00404         case MP_RAILWAY:
00405           if (!IsPlainRail(tile)) goto not_valid_below;
00406           break;
00407 
00408         case MP_ROAD:
00409           if (IsRoadDepot(tile)) goto not_valid_below;
00410           break;
00411 
00412         case MP_TUNNELBRIDGE:
00413           if (IsTunnel(tile)) break;
00414           if (direction == DiagDirToAxis(GetTunnelBridgeDirection(tile))) goto not_valid_below;
00415           if (z_start < GetBridgeHeight(tile)) goto not_valid_below;
00416           break;
00417 
00418         case MP_OBJECT: {
00419           const ObjectSpec *spec = ObjectSpec::GetByTile(tile);
00420           if ((spec->flags & OBJECT_FLAG_ALLOW_UNDER_BRIDGE) == 0) goto not_valid_below;
00421           if (GetTileMaxZ(tile) + spec->height > z_start) goto not_valid_below;
00422           break;
00423         }
00424 
00425         case MP_CLEAR:
00426           break;
00427 
00428         default:
00429   not_valid_below:;
00430           /* try and clear the middle landscape */
00431           ret = DoCommand(tile, 0, 0, flags, CMD_LANDSCAPE_CLEAR);
00432           if (ret.Failed()) return ret;
00433           cost.AddCost(ret);
00434           break;
00435       }
00436 
00437       if (flags & DC_EXEC) {
00438         /* We do this here because when replacing a bridge with another
00439          * type calling SetBridgeMiddle isn't needed. After all, the
00440          * tile already has the has_bridge_above bits set. */
00441         SetBridgeMiddle(tile, direction);
00442       }
00443     }
00444 
00445     owner = company;
00446     is_new_owner = true;
00447   }
00448 
00449   /* do the drill? */
00450   if (flags & DC_EXEC) {
00451     DiagDirection dir = AxisToDiagDir(direction);
00452 
00453     Company *c = Company::GetIfValid(owner);
00454     switch (transport_type) {
00455       case TRANSPORT_RAIL:
00456         /* Add to company infrastructure count if required. */
00457         if (is_new_owner && c != NULL) c->infrastructure.rail[railtype] += (bridge_len + 2) * TUNNELBRIDGE_TRACKBIT_FACTOR;
00458         MakeRailBridgeRamp(tile_start, owner, bridge_type, dir,                 railtype);
00459         MakeRailBridgeRamp(tile_end,   owner, bridge_type, ReverseDiagDir(dir), railtype);
00460         SetTunnelBridgeReservation(tile_start, pbs_reservation);
00461         SetTunnelBridgeReservation(tile_end,   pbs_reservation);
00462         break;
00463 
00464       case TRANSPORT_ROAD: {
00465         RoadTypes prev_roadtypes = IsBridgeTile(tile_start) ? GetRoadTypes(tile_start) : ROADTYPES_NONE;
00466         if (is_new_owner) {
00467           /* Also give unowned present roadtypes to new owner */
00468           if (HasBit(prev_roadtypes, ROADTYPE_ROAD) && GetRoadOwner(tile_start, ROADTYPE_ROAD) == OWNER_NONE) ClrBit(prev_roadtypes, ROADTYPE_ROAD);
00469           if (HasBit(prev_roadtypes, ROADTYPE_TRAM) && GetRoadOwner(tile_start, ROADTYPE_TRAM) == OWNER_NONE) ClrBit(prev_roadtypes, ROADTYPE_TRAM);
00470         }
00471         if (c != NULL) {
00472           /* Add all new road types to the company infrastructure counter. */
00473           RoadType new_rt;
00474           FOR_EACH_SET_ROADTYPE(new_rt, roadtypes ^ prev_roadtypes) {
00475             /* A full diagonal road tile has two road bits. */
00476             Company::Get(owner)->infrastructure.road[new_rt] += (bridge_len + 2) * 2 * TUNNELBRIDGE_TRACKBIT_FACTOR;
00477           }
00478         }
00479         Owner owner_road = owner;
00480         Owner owner_tram = owner;
00481         if (HasBit(prev_roadtypes, ROADTYPE_ROAD)) owner_road = GetRoadOwner(tile_start, ROADTYPE_ROAD);
00482         if (HasBit(prev_roadtypes, ROADTYPE_TRAM)) owner_tram = GetRoadOwner(tile_start, ROADTYPE_TRAM);
00483         MakeRoadBridgeRamp(tile_start, owner, owner_road, owner_tram, bridge_type, dir,                 roadtypes);
00484         MakeRoadBridgeRamp(tile_end,   owner, owner_road, owner_tram, bridge_type, ReverseDiagDir(dir), roadtypes);
00485         break;
00486       }
00487 
00488       case TRANSPORT_WATER:
00489         if (is_new_owner && c != NULL) c->infrastructure.water += (bridge_len + 2) * TUNNELBRIDGE_TRACKBIT_FACTOR;
00490         MakeAqueductBridgeRamp(tile_start, owner, dir);
00491         MakeAqueductBridgeRamp(tile_end,   owner, ReverseDiagDir(dir));
00492         break;
00493 
00494       default:
00495         NOT_REACHED();
00496     }
00497 
00498     /* Mark all tiles dirty */
00499     TileIndexDiff delta = (direction == AXIS_X ? TileDiffXY(1, 0) : TileDiffXY(0, 1));
00500     for (TileIndex tile = tile_start; tile <= tile_end; tile += delta) {
00501       MarkTileDirtyByTile(tile);
00502     }
00503     DirtyCompanyInfrastructureWindows(owner);
00504   }
00505 
00506   if ((flags & DC_EXEC) && transport_type == TRANSPORT_RAIL) {
00507     Track track = AxisToTrack(direction);
00508     AddSideToSignalBuffer(tile_start, INVALID_DIAGDIR, company);
00509     YapfNotifyTrackLayoutChange(tile_start, track);
00510   }
00511 
00512   /* for human player that builds the bridge he gets a selection to choose from bridges (DC_QUERY_COST)
00513    * It's unnecessary to execute this command every time for every bridge. So it is done only
00514    * and cost is computed in "bridge_gui.c". For AI, Towns this has to be of course calculated
00515    */
00516   Company *c = Company::GetIfValid(company);
00517   if (!(flags & DC_QUERY_COST) || (c != NULL && c->is_ai)) {
00518     bridge_len += 2; // begin and end tiles/ramps
00519 
00520     switch (transport_type) {
00521       case TRANSPORT_ROAD: cost.AddCost(bridge_len * _price[PR_BUILD_ROAD] * 2 * CountBits(roadtypes)); break;
00522       case TRANSPORT_RAIL: cost.AddCost(bridge_len * RailBuildCost(railtype)); break;
00523       default: break;
00524     }
00525 
00526     if (c != NULL) bridge_len = CalcBridgeLenCostFactor(bridge_len);
00527 
00528     if (transport_type != TRANSPORT_WATER) {
00529       cost.AddCost((int64)bridge_len * _price[PR_BUILD_BRIDGE] * GetBridgeSpec(bridge_type)->price >> 8);
00530     } else {
00531       /* Aqueducts use a separate base cost. */
00532       cost.AddCost((int64)bridge_len * _price[PR_BUILD_AQUEDUCT]);
00533     }
00534 
00535   }
00536 
00537   return cost;
00538 }
00539 
00540 
00551 CommandCost CmdBuildTunnel(TileIndex start_tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
00552 {
00553   CompanyID company = _current_company;
00554 
00555   TransportType transport_type = Extract<TransportType, 8, 2>(p1);
00556 
00557   RailType railtype = INVALID_RAILTYPE;
00558   RoadTypes rts = ROADTYPES_NONE;
00559   _build_tunnel_endtile = 0;
00560   switch (transport_type) {
00561     case TRANSPORT_RAIL:
00562       railtype = Extract<RailType, 0, 4>(p1);
00563       if (!ValParamRailtype(railtype)) return CMD_ERROR;
00564       break;
00565 
00566     case TRANSPORT_ROAD:
00567       rts = Extract<RoadTypes, 0, 2>(p1);
00568       if (!HasExactlyOneBit(rts) || !HasRoadTypesAvail(company, rts)) return CMD_ERROR;
00569       break;
00570 
00571     default: return CMD_ERROR;
00572   }
00573 
00574   if (company == OWNER_DEITY) {
00575     if (transport_type != TRANSPORT_ROAD) return CMD_ERROR;
00576     const Town *town = CalcClosestTownFromTile(start_tile);
00577 
00578     company = OWNER_TOWN;
00579 
00580     /* If we are not within a town, we are not owned by the town */
00581     if (town == NULL || DistanceSquare(start_tile, town->xy) > town->cache.squared_town_zone_radius[HZB_TOWN_EDGE]) {
00582       company = OWNER_NONE;
00583     }
00584   }
00585 
00586   int start_z;
00587   int end_z;
00588   Slope start_tileh = GetTileSlope(start_tile, &start_z);
00589   DiagDirection direction = GetInclinedSlopeDirection(start_tileh);
00590   if (direction == INVALID_DIAGDIR) return_cmd_error(STR_ERROR_SITE_UNSUITABLE_FOR_TUNNEL);
00591 
00592   if (HasTileWaterGround(start_tile)) return_cmd_error(STR_ERROR_CAN_T_BUILD_ON_WATER);
00593 
00594   CommandCost ret = DoCommand(start_tile, 0, 0, flags, CMD_LANDSCAPE_CLEAR);
00595   if (ret.Failed()) return ret;
00596 
00597   /* XXX - do NOT change 'ret' in the loop, as it is used as the price
00598    * for the clearing of the entrance of the tunnel. Assigning it to
00599    * cost before the loop will yield different costs depending on start-
00600    * position, because of increased-cost-by-length: 'cost += cost >> 3' */
00601 
00602   TileIndexDiff delta = TileOffsByDiagDir(direction);
00603   DiagDirection tunnel_in_way_dir;
00604   if (DiagDirToAxis(direction) == AXIS_Y) {
00605     tunnel_in_way_dir = (TileX(start_tile) < (MapMaxX() / 2)) ? DIAGDIR_SW : DIAGDIR_NE;
00606   } else {
00607     tunnel_in_way_dir = (TileY(start_tile) < (MapMaxX() / 2)) ? DIAGDIR_SE : DIAGDIR_NW;
00608   }
00609 
00610   TileIndex end_tile = start_tile;
00611 
00612   /* Tile shift coefficient. Will decrease for very long tunnels to avoid exponential growth of price*/
00613   int tiles_coef = 3;
00614   /* Number of tiles from start of tunnel */
00615   int tiles = 0;
00616   /* Number of tiles at which the cost increase coefficient per tile is halved */
00617   int tiles_bump = 25;
00618 
00619   CommandCost cost(EXPENSES_CONSTRUCTION);
00620   Slope end_tileh;
00621   for (;;) {
00622     end_tile += delta;
00623     if (!IsValidTile(end_tile)) return_cmd_error(STR_ERROR_TUNNEL_THROUGH_MAP_BORDER);
00624     end_tileh = GetTileSlope(end_tile, &end_z);
00625 
00626     if (start_z == end_z) break;
00627 
00628     if (!_cheats.crossing_tunnels.value && IsTunnelInWayDir(end_tile, start_z, tunnel_in_way_dir)) {
00629       return_cmd_error(STR_ERROR_ANOTHER_TUNNEL_IN_THE_WAY);
00630     }
00631 
00632     tiles++;
00633     if (tiles == tiles_bump) {
00634       tiles_coef++;
00635       tiles_bump *= 2;
00636     }
00637 
00638     cost.AddCost(_price[PR_BUILD_TUNNEL]);
00639     cost.AddCost(cost.GetCost() >> tiles_coef); // add a multiplier for longer tunnels
00640   }
00641 
00642   /* Add the cost of the entrance */
00643   cost.AddCost(_price[PR_BUILD_TUNNEL]);
00644   cost.AddCost(ret);
00645 
00646   /* if the command fails from here on we want the end tile to be highlighted */
00647   _build_tunnel_endtile = end_tile;
00648 
00649   if (tiles > _settings_game.construction.max_tunnel_length) return_cmd_error(STR_ERROR_TUNNEL_TOO_LONG);
00650 
00651   if (HasTileWaterGround(end_tile)) return_cmd_error(STR_ERROR_CAN_T_BUILD_ON_WATER);
00652 
00653   /* Clear the tile in any case */
00654   ret = DoCommand(end_tile, 0, 0, flags, CMD_LANDSCAPE_CLEAR);
00655   if (ret.Failed()) return_cmd_error(STR_ERROR_UNABLE_TO_EXCAVATE_LAND);
00656   cost.AddCost(ret);
00657 
00658   /* slope of end tile must be complementary to the slope of the start tile */
00659   if (end_tileh != ComplementSlope(start_tileh)) {
00660     /* Mark the tile as already cleared for the terraform command.
00661      * Do this for all tiles (like trees), not only objects. */
00662     ClearedObjectArea *coa = FindClearedObject(end_tile);
00663     if (coa == NULL) {
00664       coa = _cleared_object_areas.Append();
00665       coa->first_tile = end_tile;
00666       coa->area = TileArea(end_tile, 1, 1);
00667     }
00668 
00669     /* Hide the tile from the terraforming command */
00670     TileIndex old_first_tile = coa->first_tile;
00671     coa->first_tile = INVALID_TILE;
00672     ret = DoCommand(end_tile, end_tileh & start_tileh, 0, flags, CMD_TERRAFORM_LAND);
00673     coa->first_tile = old_first_tile;
00674     if (ret.Failed()) return_cmd_error(STR_ERROR_UNABLE_TO_EXCAVATE_LAND);
00675     cost.AddCost(ret);
00676   }
00677   cost.AddCost(_price[PR_BUILD_TUNNEL]);
00678 
00679   /* Pay for the rail/road in the tunnel including entrances */
00680   switch (transport_type) {
00681     case TRANSPORT_ROAD: cost.AddCost((tiles + 2) * _price[PR_BUILD_ROAD] * 2); break;
00682     case TRANSPORT_RAIL: cost.AddCost((tiles + 2) * RailBuildCost(railtype)); break;
00683     default: NOT_REACHED();
00684   }
00685 
00686   if (flags & DC_EXEC) {
00687     Company *c = Company::GetIfValid(company);
00688     uint num_pieces = (tiles + 2) * TUNNELBRIDGE_TRACKBIT_FACTOR;
00689     if (transport_type == TRANSPORT_RAIL) {
00690       if (!IsTunnelTile(start_tile) && c != NULL) c->infrastructure.rail[railtype] += num_pieces;
00691       MakeRailTunnel(start_tile, company, direction,                 railtype);
00692       MakeRailTunnel(end_tile,   company, ReverseDiagDir(direction), railtype);
00693       AddSideToSignalBuffer(start_tile, INVALID_DIAGDIR, company);
00694       YapfNotifyTrackLayoutChange(start_tile, DiagDirToDiagTrack(direction));
00695     } else {
00696       if (c != NULL) {
00697         RoadType rt;
00698         FOR_EACH_SET_ROADTYPE(rt, rts ^ (IsTunnelTile(start_tile) ? GetRoadTypes(start_tile) : ROADTYPES_NONE)) {
00699           c->infrastructure.road[rt] += num_pieces * 2; // A full diagonal road has two road bits.
00700         }
00701       }
00702       MakeRoadTunnel(start_tile, company, direction,                 rts);
00703       MakeRoadTunnel(end_tile,   company, ReverseDiagDir(direction), rts);
00704     }
00705     DirtyCompanyInfrastructureWindows(company);
00706   }
00707 
00708   return cost;
00709 }
00710 
00711 
00717 static inline CommandCost CheckAllowRemoveTunnelBridge(TileIndex tile)
00718 {
00719   /* Floods can remove anything as well as the scenario editor */
00720   if (_current_company == OWNER_WATER || _game_mode == GM_EDITOR) return CommandCost();
00721 
00722   switch (GetTunnelBridgeTransportType(tile)) {
00723     case TRANSPORT_ROAD: {
00724       RoadTypes rts = GetRoadTypes(tile);
00725       Owner road_owner = _current_company;
00726       Owner tram_owner = _current_company;
00727 
00728       if (HasBit(rts, ROADTYPE_ROAD)) road_owner = GetRoadOwner(tile, ROADTYPE_ROAD);
00729       if (HasBit(rts, ROADTYPE_TRAM)) tram_owner = GetRoadOwner(tile, ROADTYPE_TRAM);
00730 
00731       /* We can remove unowned road and if the town allows it */
00732       if (road_owner == OWNER_TOWN && _current_company != OWNER_TOWN && !(_settings_game.construction.extra_dynamite || _cheats.magic_bulldozer.value)) {
00733         /* Town does not allow */
00734         return CheckTileOwnership(tile);
00735       }
00736       if (road_owner == OWNER_NONE || road_owner == OWNER_TOWN) road_owner = _current_company;
00737       if (tram_owner == OWNER_NONE) tram_owner = _current_company;
00738 
00739       CommandCost ret = CheckOwnership(road_owner, tile);
00740       if (ret.Succeeded()) ret = CheckOwnership(tram_owner, tile);
00741       return ret;
00742     }
00743 
00744     case TRANSPORT_RAIL:
00745       return CheckOwnership(GetTileOwner(tile));
00746 
00747     case TRANSPORT_WATER: {
00748       /* Always allow to remove aqueducts without owner. */
00749       Owner aqueduct_owner = GetTileOwner(tile);
00750       if (aqueduct_owner == OWNER_NONE) aqueduct_owner = _current_company;
00751       return CheckOwnership(aqueduct_owner);
00752     }
00753 
00754     default: NOT_REACHED();
00755   }
00756 }
00757 
00764 static CommandCost DoClearTunnel(TileIndex tile, DoCommandFlag flags)
00765 {
00766   CommandCost ret = CheckAllowRemoveTunnelBridge(tile);
00767   if (ret.Failed()) return ret;
00768 
00769   TileIndex endtile = GetOtherTunnelEnd(tile);
00770 
00771   ret = TunnelBridgeIsFree(tile, endtile);
00772   if (ret.Failed()) return ret;
00773 
00774   _build_tunnel_endtile = endtile;
00775 
00776   Town *t = NULL;
00777   if (IsTileOwner(tile, OWNER_TOWN) && _game_mode != GM_EDITOR) {
00778     t = ClosestTownFromTile(tile, UINT_MAX); // town penalty rating
00779 
00780     /* Check if you are allowed to remove the tunnel owned by a town
00781      * Removal depends on difficulty settings */
00782     CommandCost ret = CheckforTownRating(flags, t, TUNNELBRIDGE_REMOVE);
00783     if (ret.Failed()) return ret;
00784   }
00785 
00786   /* checks if the owner is town then decrease town rating by RATING_TUNNEL_BRIDGE_DOWN_STEP until
00787    * you have a "Poor" (0) town rating */
00788   if (IsTileOwner(tile, OWNER_TOWN) && _game_mode != GM_EDITOR) {
00789     ChangeTownRating(t, RATING_TUNNEL_BRIDGE_DOWN_STEP, RATING_TUNNEL_BRIDGE_MINIMUM, flags);
00790   }
00791 
00792   uint len = GetTunnelBridgeLength(tile, endtile) + 2; // Don't forget the end tiles.
00793 
00794   if (flags & DC_EXEC) {
00795     if (GetTunnelBridgeTransportType(tile) == TRANSPORT_RAIL) {
00796       /* We first need to request values before calling DoClearSquare */
00797       DiagDirection dir = GetTunnelBridgeDirection(tile);
00798       Track track = DiagDirToDiagTrack(dir);
00799       Owner owner = GetTileOwner(tile);
00800 
00801       Train *v = NULL;
00802       if (HasTunnelBridgeReservation(tile)) {
00803         v = GetTrainForReservation(tile, track);
00804         if (v != NULL) FreeTrainTrackReservation(v);
00805       }
00806 
00807       if (Company::IsValidID(owner)) {
00808         Company::Get(owner)->infrastructure.rail[GetRailType(tile)] -= len * TUNNELBRIDGE_TRACKBIT_FACTOR;
00809         DirtyCompanyInfrastructureWindows(owner);
00810       }
00811 
00812       DoClearSquare(tile);
00813       DoClearSquare(endtile);
00814 
00815       /* cannot use INVALID_DIAGDIR for signal update because the tunnel doesn't exist anymore */
00816       AddSideToSignalBuffer(tile,    ReverseDiagDir(dir), owner);
00817       AddSideToSignalBuffer(endtile, dir,                 owner);
00818 
00819       YapfNotifyTrackLayoutChange(tile,    track);
00820       YapfNotifyTrackLayoutChange(endtile, track);
00821 
00822       if (v != NULL) TryPathReserve(v);
00823     } else {
00824       RoadType rt;
00825       FOR_EACH_SET_ROADTYPE(rt, GetRoadTypes(tile)) {
00826         /* A full diagonal road tile has two road bits. */
00827         Company *c = Company::GetIfValid(GetRoadOwner(tile, rt));
00828         if (c != NULL) {
00829           c->infrastructure.road[rt] -= len * 2 * TUNNELBRIDGE_TRACKBIT_FACTOR;
00830           DirtyCompanyInfrastructureWindows(c->index);
00831         }
00832       }
00833 
00834       DoClearSquare(tile);
00835       DoClearSquare(endtile);
00836     }
00837   }
00838   return CommandCost(EXPENSES_CONSTRUCTION, _price[PR_CLEAR_TUNNEL] * len);
00839 }
00840 
00841 
00848 static CommandCost DoClearBridge(TileIndex tile, DoCommandFlag flags)
00849 {
00850   CommandCost ret = CheckAllowRemoveTunnelBridge(tile);
00851   if (ret.Failed()) return ret;
00852 
00853   TileIndex endtile = GetOtherBridgeEnd(tile);
00854 
00855   ret = TunnelBridgeIsFree(tile, endtile);
00856   if (ret.Failed()) return ret;
00857 
00858   DiagDirection direction = GetTunnelBridgeDirection(tile);
00859   TileIndexDiff delta = TileOffsByDiagDir(direction);
00860 
00861   Town *t = NULL;
00862   if (IsTileOwner(tile, OWNER_TOWN) && _game_mode != GM_EDITOR) {
00863     t = ClosestTownFromTile(tile, UINT_MAX); // town penalty rating
00864 
00865     /* Check if you are allowed to remove the bridge owned by a town
00866      * Removal depends on difficulty settings */
00867     CommandCost ret = CheckforTownRating(flags, t, TUNNELBRIDGE_REMOVE);
00868     if (ret.Failed()) return ret;
00869   }
00870 
00871   /* checks if the owner is town then decrease town rating by RATING_TUNNEL_BRIDGE_DOWN_STEP until
00872    * you have a "Poor" (0) town rating */
00873   if (IsTileOwner(tile, OWNER_TOWN) && _game_mode != GM_EDITOR) {
00874     ChangeTownRating(t, RATING_TUNNEL_BRIDGE_DOWN_STEP, RATING_TUNNEL_BRIDGE_MINIMUM, flags);
00875   }
00876 
00877   Money base_cost = (GetTunnelBridgeTransportType(tile) != TRANSPORT_WATER) ? _price[PR_CLEAR_BRIDGE] : _price[PR_CLEAR_AQUEDUCT];
00878   uint len = GetTunnelBridgeLength(tile, endtile) + 2; // Don't forget the end tiles.
00879 
00880   if (flags & DC_EXEC) {
00881     /* read this value before actual removal of bridge */
00882     bool rail = GetTunnelBridgeTransportType(tile) == TRANSPORT_RAIL;
00883     Owner owner = GetTileOwner(tile);
00884     int height = GetBridgeHeight(tile);
00885     Train *v = NULL;
00886 
00887     if (rail && HasTunnelBridgeReservation(tile)) {
00888       v = GetTrainForReservation(tile, DiagDirToDiagTrack(direction));
00889       if (v != NULL) FreeTrainTrackReservation(v);
00890     }
00891 
00892     /* Update company infrastructure counts. */
00893     if (rail) {
00894       if (Company::IsValidID(owner)) Company::Get(owner)->infrastructure.rail[GetRailType(tile)] -= len * TUNNELBRIDGE_TRACKBIT_FACTOR;
00895     } else if (GetTunnelBridgeTransportType(tile) == TRANSPORT_ROAD) {
00896       RoadType rt;
00897       FOR_EACH_SET_ROADTYPE(rt, GetRoadTypes(tile)) {
00898         Company *c = Company::GetIfValid(GetRoadOwner(tile, rt));
00899         if (c != NULL) {
00900           /* A full diagonal road tile has two road bits. */
00901           c->infrastructure.road[rt] -= len * 2 * TUNNELBRIDGE_TRACKBIT_FACTOR;
00902           DirtyCompanyInfrastructureWindows(c->index);
00903         }
00904       }
00905     } else { // Aqueduct
00906       if (Company::IsValidID(owner)) Company::Get(owner)->infrastructure.water -= len * TUNNELBRIDGE_TRACKBIT_FACTOR;
00907     }
00908     DirtyCompanyInfrastructureWindows(owner);
00909 
00910     DoClearSquare(tile);
00911     DoClearSquare(endtile);
00912     for (TileIndex c = tile + delta; c != endtile; c += delta) {
00913       /* do not let trees appear from 'nowhere' after removing bridge */
00914       if (IsNormalRoadTile(c) && GetRoadside(c) == ROADSIDE_TREES) {
00915         int minz = GetTileMaxZ(c) + 3;
00916         if (height < minz) SetRoadside(c, ROADSIDE_PAVED);
00917       }
00918       ClearBridgeMiddle(c);
00919       MarkTileDirtyByTile(c);
00920     }
00921 
00922     if (rail) {
00923       /* cannot use INVALID_DIAGDIR for signal update because the bridge doesn't exist anymore */
00924       AddSideToSignalBuffer(tile,    ReverseDiagDir(direction), owner);
00925       AddSideToSignalBuffer(endtile, direction,                 owner);
00926 
00927       Track track = DiagDirToDiagTrack(direction);
00928       YapfNotifyTrackLayoutChange(tile,    track);
00929       YapfNotifyTrackLayoutChange(endtile, track);
00930 
00931       if (v != NULL) TryPathReserve(v, true);
00932     }
00933   }
00934 
00935   return CommandCost(EXPENSES_CONSTRUCTION, len * base_cost);
00936 }
00937 
00944 static CommandCost ClearTile_TunnelBridge(TileIndex tile, DoCommandFlag flags)
00945 {
00946   if (IsTunnel(tile)) {
00947     if (flags & DC_AUTO) return_cmd_error(STR_ERROR_MUST_DEMOLISH_TUNNEL_FIRST);
00948     return DoClearTunnel(tile, flags);
00949   } else { // IsBridge(tile)
00950     if (flags & DC_AUTO) return_cmd_error(STR_ERROR_MUST_DEMOLISH_BRIDGE_FIRST);
00951     return DoClearBridge(tile, flags);
00952   }
00953 }
00954 
00965 static inline void DrawPillar(const PalSpriteID *psid, int x, int y, int z, int w, int h, const SubSprite *subsprite)
00966 {
00967   static const int PILLAR_Z_OFFSET = TILE_HEIGHT - BRIDGE_Z_START; 
00968   AddSortableSpriteToDraw(psid->sprite, psid->pal, x, y, w, h, BB_HEIGHT_UNDER_BRIDGE - PILLAR_Z_OFFSET, z, IsTransparencySet(TO_BRIDGES), 0, 0, -PILLAR_Z_OFFSET, subsprite);
00969 }
00970 
00982 static int DrawPillarColumn(int z_bottom, int z_top, const PalSpriteID *psid, int x, int y, int w, int h)
00983 {
00984   int cur_z;
00985   for (cur_z = z_top; cur_z >= z_bottom; cur_z -= TILE_HEIGHT) {
00986     DrawPillar(psid, x, y, cur_z, w, h, NULL);
00987   }
00988   return cur_z;
00989 }
00990 
01002 static void DrawBridgePillars(const PalSpriteID *psid, const TileInfo *ti, Axis axis, bool drawfarpillar, int x, int y, int z_bridge)
01003 {
01004   static const int bounding_box_size[2]  = {16, 2}; 
01005   static const int back_pillar_offset[2] = { 0, 9}; 
01006 
01007   static const int INF = 1000; 
01008   static const SubSprite half_pillar_sub_sprite[2][2] = {
01009     { {  -14, -INF, INF, INF }, { -INF, -INF, -15, INF } }, // X axis, north and south
01010     { { -INF, -INF,  15, INF }, {   16, -INF, INF, INF } }, // Y axis, north and south
01011   };
01012 
01013   if (psid->sprite == 0) return;
01014 
01015   /* Determine ground height under pillars */
01016   DiagDirection south_dir = AxisToDiagDir(axis);
01017   int z_front_north = ti->z;
01018   int z_back_north = ti->z;
01019   int z_front_south = ti->z;
01020   int z_back_south = ti->z;
01021   GetSlopePixelZOnEdge(ti->tileh, south_dir, &z_front_south, &z_back_south);
01022   GetSlopePixelZOnEdge(ti->tileh, ReverseDiagDir(south_dir), &z_front_north, &z_back_north);
01023 
01024   /* Shared height of pillars */
01025   int z_front = max(z_front_north, z_front_south);
01026   int z_back = max(z_back_north, z_back_south);
01027 
01028   /* x and y size of bounding-box of pillars */
01029   int w = bounding_box_size[axis];
01030   int h = bounding_box_size[OtherAxis(axis)];
01031   /* sprite position of back facing pillar */
01032   int x_back = x - back_pillar_offset[axis];
01033   int y_back = y - back_pillar_offset[OtherAxis(axis)];
01034 
01035   /* Draw front pillars */
01036   int bottom_z = DrawPillarColumn(z_front, z_bridge, psid, x, y, w, h);
01037   if (z_front_north < z_front) DrawPillar(psid, x, y, bottom_z, w, h, &half_pillar_sub_sprite[axis][0]);
01038   if (z_front_south < z_front) DrawPillar(psid, x, y, bottom_z, w, h, &half_pillar_sub_sprite[axis][1]);
01039 
01040   /* Draw back pillars, skip top two parts, which are hidden by the bridge */
01041   int z_bridge_back = z_bridge - 2 * (int)TILE_HEIGHT;
01042   if (drawfarpillar && (z_back_north <= z_bridge_back || z_back_south <= z_bridge_back)) {
01043     bottom_z = DrawPillarColumn(z_back, z_bridge_back, psid, x_back, y_back, w, h);
01044     if (z_back_north < z_back) DrawPillar(psid, x_back, y_back, bottom_z, w, h, &half_pillar_sub_sprite[axis][0]);
01045     if (z_back_south < z_back) DrawPillar(psid, x_back, y_back, bottom_z, w, h, &half_pillar_sub_sprite[axis][1]);
01046   }
01047 }
01048 
01058 static void DrawBridgeTramBits(int x, int y, int z, int offset, bool overlay, bool head)
01059 {
01060   static const SpriteID tram_offsets[2][6] = { { 107, 108, 109, 110, 111, 112 }, { 4, 5, 15, 16, 17, 18 } };
01061   static const SpriteID back_offsets[6]    =   {  95,  96,  99, 102, 100, 101 };
01062   static const SpriteID front_offsets[6]   =   {  97,  98, 103, 106, 104, 105 };
01063 
01064   static const uint size_x[6] = {  1, 16, 16,  1, 16,  1 };
01065   static const uint size_y[6] = { 16,  1,  1, 16,  1, 16 };
01066   static const uint front_bb_offset_x[6] = { 15,  0,  0, 15,  0, 15 };
01067   static const uint front_bb_offset_y[6] = {  0, 15, 15,  0, 15,  0 };
01068 
01069   /* The sprites under the vehicles are drawn as SpriteCombine. StartSpriteCombine() has already been called
01070    * The bounding boxes here are the same as for bridge front/roof */
01071   if (head || !IsInvisibilitySet(TO_BRIDGES)) {
01072     AddSortableSpriteToDraw(SPR_TRAMWAY_BASE + tram_offsets[overlay][offset], PAL_NONE,
01073       x, y, size_x[offset], size_y[offset], 0x28, z,
01074       !head && IsTransparencySet(TO_BRIDGES));
01075   }
01076 
01077   /* Do not draw catenary if it is set invisible */
01078   if (!IsInvisibilitySet(TO_CATENARY)) {
01079     AddSortableSpriteToDraw(SPR_TRAMWAY_BASE + back_offsets[offset], PAL_NONE,
01080       x, y, size_x[offset], size_y[offset], 0x28, z,
01081       IsTransparencySet(TO_CATENARY));
01082   }
01083 
01084   /* Start a new SpriteCombine for the front part */
01085   EndSpriteCombine();
01086   StartSpriteCombine();
01087 
01088   /* For sloped sprites the bounding box needs to be higher, as the pylons stop on a higher point */
01089   if (!IsInvisibilitySet(TO_CATENARY)) {
01090     AddSortableSpriteToDraw(SPR_TRAMWAY_BASE + front_offsets[offset], PAL_NONE,
01091       x, y, size_x[offset] + front_bb_offset_x[offset], size_y[offset] + front_bb_offset_y[offset], 0x28, z,
01092       IsTransparencySet(TO_CATENARY), front_bb_offset_x[offset], front_bb_offset_y[offset]);
01093   }
01094 }
01095 
01109 static void DrawTile_TunnelBridge(TileInfo *ti)
01110 {
01111   TransportType transport_type = GetTunnelBridgeTransportType(ti->tile);
01112   DiagDirection tunnelbridge_direction = GetTunnelBridgeDirection(ti->tile);
01113 
01114   if (IsTunnel(ti->tile)) {
01115     /* Front view of tunnel bounding boxes:
01116      *
01117      *   122223  <- BB_Z_SEPARATOR
01118      *   1    3
01119      *   1    3                1,3 = empty helper BB
01120      *   1    3                  2 = SpriteCombine of tunnel-roof and catenary (tram & elrail)
01121      *
01122      */
01123 
01124     static const int _tunnel_BB[4][12] = {
01125       /*  tunnnel-roof  |  Z-separator  | tram-catenary
01126        * w  h  bb_x bb_y| x   y   w   h |bb_x bb_y w h */
01127       {  1,  0, -15, -14,  0, 15, 16,  1, 0, 1, 16, 15 }, // NE
01128       {  0,  1, -14, -15, 15,  0,  1, 16, 1, 0, 15, 16 }, // SE
01129       {  1,  0, -15, -14,  0, 15, 16,  1, 0, 1, 16, 15 }, // SW
01130       {  0,  1, -14, -15, 15,  0,  1, 16, 1, 0, 15, 16 }, // NW
01131     };
01132     const int *BB_data = _tunnel_BB[tunnelbridge_direction];
01133 
01134     bool catenary = false;
01135 
01136     SpriteID image;
01137     SpriteID railtype_overlay = 0;
01138     if (transport_type == TRANSPORT_RAIL) {
01139       const RailtypeInfo *rti = GetRailTypeInfo(GetRailType(ti->tile));
01140       image = rti->base_sprites.tunnel;
01141       if (rti->UsesOverlay()) {
01142         /* Check if the railtype has custom tunnel portals. */
01143         railtype_overlay = GetCustomRailSprite(rti, ti->tile, RTSG_TUNNEL_PORTAL);
01144         if (railtype_overlay != 0) image = SPR_RAILTYPE_TUNNEL_BASE; // Draw blank grass tunnel base.
01145       }
01146     } else {
01147       image = SPR_TUNNEL_ENTRY_REAR_ROAD;
01148     }
01149 
01150     if (HasTunnelBridgeSnowOrDesert(ti->tile)) image += railtype_overlay != 0 ? 8 : 32;
01151 
01152     image += tunnelbridge_direction * 2;
01153     DrawGroundSprite(image, PAL_NONE);
01154 
01155     if (transport_type == TRANSPORT_ROAD) {
01156       RoadTypes rts = GetRoadTypes(ti->tile);
01157 
01158       if (HasBit(rts, ROADTYPE_TRAM)) {
01159         static const SpriteID tunnel_sprites[2][4] = { { 28, 78, 79, 27 }, {  5, 76, 77,  4 } };
01160 
01161         DrawGroundSprite(SPR_TRAMWAY_BASE + tunnel_sprites[rts - ROADTYPES_TRAM][tunnelbridge_direction], PAL_NONE);
01162 
01163         /* Do not draw wires if they are invisible */
01164         if (!IsInvisibilitySet(TO_CATENARY)) {
01165           catenary = true;
01166           StartSpriteCombine();
01167           AddSortableSpriteToDraw(SPR_TRAMWAY_TUNNEL_WIRES + tunnelbridge_direction, PAL_NONE, ti->x, ti->y, BB_data[10], BB_data[11], TILE_HEIGHT, ti->z, IsTransparencySet(TO_CATENARY), BB_data[8], BB_data[9], BB_Z_SEPARATOR);
01168         }
01169       }
01170     } else {
01171       const RailtypeInfo *rti = GetRailTypeInfo(GetRailType(ti->tile));
01172       if (rti->UsesOverlay()) {
01173         SpriteID surface = GetCustomRailSprite(rti, ti->tile, RTSG_TUNNEL);
01174         if (surface != 0) DrawGroundSprite(surface + tunnelbridge_direction, PAL_NONE);
01175       }
01176 
01177       /* PBS debugging, draw reserved tracks darker */
01178       if (_game_mode != GM_MENU && _settings_client.gui.show_track_reservation && HasTunnelBridgeReservation(ti->tile)) {
01179         DrawGroundSprite(DiagDirToAxis(tunnelbridge_direction) == AXIS_X ? rti->base_sprites.single_x : rti->base_sprites.single_y, PALETTE_CRASH);
01180       }
01181 
01182       if (HasCatenaryDrawn(GetRailType(ti->tile))) {
01183         /* Maybe draw pylons on the entry side */
01184         DrawCatenary(ti);
01185 
01186         catenary = true;
01187         StartSpriteCombine();
01188         /* Draw wire above the ramp */
01189         DrawCatenaryOnTunnel(ti);
01190       }
01191     }
01192 
01193     if (railtype_overlay != 0 && !catenary) StartSpriteCombine();
01194 
01195     AddSortableSpriteToDraw(image + 1, PAL_NONE, ti->x + TILE_SIZE - 1, ti->y + TILE_SIZE - 1, BB_data[0], BB_data[1], TILE_HEIGHT, ti->z, false, BB_data[2], BB_data[3], BB_Z_SEPARATOR);
01196     /* Draw railtype tunnel portal overlay if defined. */
01197     if (railtype_overlay != 0) AddSortableSpriteToDraw(railtype_overlay + tunnelbridge_direction, PAL_NONE, ti->x + TILE_SIZE - 1, ti->y + TILE_SIZE - 1, BB_data[0], BB_data[1], TILE_HEIGHT, ti->z, false, BB_data[2], BB_data[3], BB_Z_SEPARATOR);
01198 
01199     if (catenary || railtype_overlay != 0) EndSpriteCombine();
01200 
01201     /* Add helper BB for sprite sorting that separates the tunnel from things beside of it. */
01202     AddSortableSpriteToDraw(SPR_EMPTY_BOUNDING_BOX, PAL_NONE, ti->x,              ti->y,              BB_data[6], BB_data[7], TILE_HEIGHT, ti->z);
01203     AddSortableSpriteToDraw(SPR_EMPTY_BOUNDING_BOX, PAL_NONE, ti->x + BB_data[4], ti->y + BB_data[5], BB_data[6], BB_data[7], TILE_HEIGHT, ti->z);
01204 
01205     DrawBridgeMiddle(ti);
01206   } else { // IsBridge(ti->tile)
01207     const PalSpriteID *psid;
01208     int base_offset;
01209     bool ice = HasTunnelBridgeSnowOrDesert(ti->tile);
01210 
01211     if (transport_type == TRANSPORT_RAIL) {
01212       base_offset = GetRailTypeInfo(GetRailType(ti->tile))->bridge_offset;
01213       assert(base_offset != 8); // This one is used for roads
01214     } else {
01215       base_offset = 8;
01216     }
01217 
01218     /* as the lower 3 bits are used for other stuff, make sure they are clear */
01219     assert( (base_offset & 0x07) == 0x00);
01220 
01221     DrawFoundation(ti, GetBridgeFoundation(ti->tileh, DiagDirToAxis(tunnelbridge_direction)));
01222 
01223     /* HACK Wizardry to convert the bridge ramp direction into a sprite offset */
01224     base_offset += (6 - tunnelbridge_direction) % 4;
01225 
01226     /* Table number BRIDGE_PIECE_HEAD always refers to the bridge heads for any bridge type */
01227     if (transport_type != TRANSPORT_WATER) {
01228       if (ti->tileh == SLOPE_FLAT) base_offset += 4; // sloped bridge head
01229       psid = &GetBridgeSpriteTable(GetBridgeType(ti->tile), BRIDGE_PIECE_HEAD)[base_offset];
01230     } else {
01231       psid = _aqueduct_sprites + base_offset;
01232     }
01233 
01234     if (!ice) {
01235       TileIndex next = ti->tile + TileOffsByDiagDir(tunnelbridge_direction);
01236       if (ti->tileh != SLOPE_FLAT && ti->z == 0 && HasTileWaterClass(next) && GetWaterClass(next) == WATER_CLASS_SEA) {
01237         DrawShoreTile(ti->tileh);
01238       } else {
01239         DrawClearLandTile(ti, 3);
01240       }
01241     } else {
01242       DrawGroundSprite(SPR_FLAT_SNOW_DESERT_TILE + SlopeToSpriteOffset(ti->tileh), PAL_NONE);
01243     }
01244 
01245     /* draw ramp */
01246 
01247     /* Draw Trambits and PBS Reservation as SpriteCombine */
01248     if (transport_type == TRANSPORT_ROAD || transport_type == TRANSPORT_RAIL) StartSpriteCombine();
01249 
01250     /* HACK set the height of the BB of a sloped ramp to 1 so a vehicle on
01251      * it doesn't disappear behind it
01252      */
01253     /* Bridge heads are drawn solid no matter how invisibility/transparency is set */
01254     AddSortableSpriteToDraw(psid->sprite, psid->pal, ti->x, ti->y, 16, 16, ti->tileh == SLOPE_FLAT ? 0 : 8, ti->z);
01255 
01256     if (transport_type == TRANSPORT_ROAD) {
01257       RoadTypes rts = GetRoadTypes(ti->tile);
01258 
01259       if (HasBit(rts, ROADTYPE_TRAM)) {
01260         uint offset = tunnelbridge_direction;
01261         int z = ti->z;
01262         if (ti->tileh != SLOPE_FLAT) {
01263           offset = (offset + 1) & 1;
01264           z += TILE_HEIGHT;
01265         } else {
01266           offset += 2;
01267         }
01268         /* DrawBridgeTramBits() calls EndSpriteCombine() and StartSpriteCombine() */
01269         DrawBridgeTramBits(ti->x, ti->y, z, offset, HasBit(rts, ROADTYPE_ROAD), true);
01270       }
01271       EndSpriteCombine();
01272     } else if (transport_type == TRANSPORT_RAIL) {
01273       const RailtypeInfo *rti = GetRailTypeInfo(GetRailType(ti->tile));
01274       if (rti->UsesOverlay()) {
01275         SpriteID surface = GetCustomRailSprite(rti, ti->tile, RTSG_BRIDGE);
01276         if (surface != 0) {
01277           if (HasBridgeFlatRamp(ti->tileh, DiagDirToAxis(tunnelbridge_direction))) {
01278             AddSortableSpriteToDraw(surface + ((DiagDirToAxis(tunnelbridge_direction) == AXIS_X) ? RTBO_X : RTBO_Y), PAL_NONE, ti->x, ti->y, 16, 16, 0, ti->z + 8);
01279           } else {
01280             AddSortableSpriteToDraw(surface + RTBO_SLOPE + tunnelbridge_direction, PAL_NONE, ti->x, ti->y, 16, 16, 8, ti->z);
01281           }
01282         }
01283         /* Don't fallback to non-overlay sprite -- the spec states that
01284          * if an overlay is present then the bridge surface must be
01285          * present. */
01286       }
01287 
01288       /* PBS debugging, draw reserved tracks darker */
01289       if (_game_mode != GM_MENU &&_settings_client.gui.show_track_reservation && HasTunnelBridgeReservation(ti->tile)) {
01290         if (HasBridgeFlatRamp(ti->tileh, DiagDirToAxis(tunnelbridge_direction))) {
01291           AddSortableSpriteToDraw(DiagDirToAxis(tunnelbridge_direction) == AXIS_X ? rti->base_sprites.single_x : rti->base_sprites.single_y, PALETTE_CRASH, ti->x, ti->y, 16, 16, 0, ti->z + 8);
01292         } else {
01293           AddSortableSpriteToDraw(rti->base_sprites.single_sloped + tunnelbridge_direction, PALETTE_CRASH, ti->x, ti->y, 16, 16, 8, ti->z);
01294         }
01295       }
01296 
01297       EndSpriteCombine();
01298       if (HasCatenaryDrawn(GetRailType(ti->tile))) {
01299         DrawCatenary(ti);
01300       }
01301     }
01302 
01303     DrawBridgeMiddle(ti);
01304   }
01305 }
01306 
01307 
01326 static BridgePieces CalcBridgePiece(uint north, uint south)
01327 {
01328   if (north == 1) {
01329     return BRIDGE_PIECE_NORTH;
01330   } else if (south == 1) {
01331     return BRIDGE_PIECE_SOUTH;
01332   } else if (north < south) {
01333     return north & 1 ? BRIDGE_PIECE_INNER_SOUTH : BRIDGE_PIECE_INNER_NORTH;
01334   } else if (north > south) {
01335     return south & 1 ? BRIDGE_PIECE_INNER_NORTH : BRIDGE_PIECE_INNER_SOUTH;
01336   } else {
01337     return north & 1 ? BRIDGE_PIECE_MIDDLE_EVEN : BRIDGE_PIECE_MIDDLE_ODD;
01338   }
01339 }
01340 
01345 void DrawBridgeMiddle(const TileInfo *ti)
01346 {
01347   /* Sectional view of bridge bounding boxes:
01348    *
01349    *  1           2                                1,2 = SpriteCombine of Bridge front/(back&floor) and TramCatenary
01350    *  1           2                                  3 = empty helper BB
01351    *  1     7     2                                4,5 = pillars under higher bridges
01352    *  1 6 88888 6 2                                  6 = elrail-pylons
01353    *  1 6 88888 6 2                                  7 = elrail-wire
01354    *  1 6 88888 6 2  <- TILE_HEIGHT                  8 = rail-vehicle on bridge
01355    *  3333333333333  <- BB_Z_SEPARATOR
01356    *                 <- unused
01357    *    4       5    <- BB_HEIGHT_UNDER_BRIDGE
01358    *    4       5
01359    *    4       5
01360    *
01361    */
01362 
01363   if (!IsBridgeAbove(ti->tile)) return;
01364 
01365   TileIndex rampnorth = GetNorthernBridgeEnd(ti->tile);
01366   TileIndex rampsouth = GetSouthernBridgeEnd(ti->tile);
01367   TransportType transport_type = GetTunnelBridgeTransportType(rampsouth);
01368 
01369   Axis axis = GetBridgeAxis(ti->tile);
01370   BridgePieces piece = CalcBridgePiece(
01371     GetTunnelBridgeLength(ti->tile, rampnorth) + 1,
01372     GetTunnelBridgeLength(ti->tile, rampsouth) + 1
01373   );
01374 
01375   const PalSpriteID *psid;
01376   bool drawfarpillar;
01377   if (transport_type != TRANSPORT_WATER) {
01378     BridgeType type =  GetBridgeType(rampsouth);
01379     drawfarpillar = !HasBit(GetBridgeSpec(type)->flags, 0);
01380 
01381     uint base_offset;
01382     if (transport_type == TRANSPORT_RAIL) {
01383       base_offset = GetRailTypeInfo(GetRailType(rampsouth))->bridge_offset;
01384     } else {
01385       base_offset = 8;
01386     }
01387 
01388     psid = base_offset + GetBridgeSpriteTable(type, piece);
01389   } else {
01390     drawfarpillar = true;
01391     psid = _aqueduct_sprites;
01392   }
01393 
01394   if (axis != AXIS_X) psid += 4;
01395 
01396   int x = ti->x;
01397   int y = ti->y;
01398   uint bridge_z = GetBridgePixelHeight(rampsouth);
01399   int z = bridge_z - BRIDGE_Z_START;
01400 
01401   /* Add a bounding box that separates the bridge from things below it. */
01402   AddSortableSpriteToDraw(SPR_EMPTY_BOUNDING_BOX, PAL_NONE, x, y, 16, 16, 1, bridge_z - TILE_HEIGHT + BB_Z_SEPARATOR);
01403 
01404   /* Draw Trambits as SpriteCombine */
01405   if (transport_type == TRANSPORT_ROAD || transport_type == TRANSPORT_RAIL) StartSpriteCombine();
01406 
01407   /* Draw floor and far part of bridge*/
01408   if (!IsInvisibilitySet(TO_BRIDGES)) {
01409     if (axis == AXIS_X) {
01410       AddSortableSpriteToDraw(psid->sprite, psid->pal, x, y, 16, 1, 0x28, z, IsTransparencySet(TO_BRIDGES), 0, 0, BRIDGE_Z_START);
01411     } else {
01412       AddSortableSpriteToDraw(psid->sprite, psid->pal, x, y, 1, 16, 0x28, z, IsTransparencySet(TO_BRIDGES), 0, 0, BRIDGE_Z_START);
01413     }
01414   }
01415 
01416   psid++;
01417 
01418   if (transport_type == TRANSPORT_ROAD) {
01419     RoadTypes rts = GetRoadTypes(rampsouth);
01420 
01421     if (HasBit(rts, ROADTYPE_TRAM)) {
01422       /* DrawBridgeTramBits() calls EndSpriteCombine() and StartSpriteCombine() */
01423       DrawBridgeTramBits(x, y, bridge_z, axis ^ 1, HasBit(rts, ROADTYPE_ROAD), false);
01424     } else {
01425       EndSpriteCombine();
01426       StartSpriteCombine();
01427     }
01428   } else if (transport_type == TRANSPORT_RAIL) {
01429     const RailtypeInfo *rti = GetRailTypeInfo(GetRailType(rampsouth));
01430     if (rti->UsesOverlay() && !IsInvisibilitySet(TO_BRIDGES)) {
01431       SpriteID surface = GetCustomRailSprite(rti, rampsouth, RTSG_BRIDGE, TCX_ON_BRIDGE);
01432       if (surface != 0) {
01433         AddSortableSpriteToDraw(surface + axis, PAL_NONE, x, y, 16, 16, 0, bridge_z, IsTransparencySet(TO_BRIDGES));
01434       }
01435     }
01436     EndSpriteCombine();
01437 
01438     if (HasCatenaryDrawn(GetRailType(rampsouth))) {
01439       DrawCatenaryOnBridge(ti);
01440     }
01441   }
01442 
01443   /* draw roof, the component of the bridge which is logically between the vehicle and the camera */
01444   if (!IsInvisibilitySet(TO_BRIDGES)) {
01445     if (axis == AXIS_X) {
01446       y += 12;
01447       if (psid->sprite & SPRITE_MASK) AddSortableSpriteToDraw(psid->sprite, psid->pal, x, y, 16, 4, 0x28, z, IsTransparencySet(TO_BRIDGES), 0, 3, BRIDGE_Z_START);
01448     } else {
01449       x += 12;
01450       if (psid->sprite & SPRITE_MASK) AddSortableSpriteToDraw(psid->sprite, psid->pal, x, y, 4, 16, 0x28, z, IsTransparencySet(TO_BRIDGES), 3, 0, BRIDGE_Z_START);
01451     }
01452   }
01453 
01454   /* Draw TramFront as SpriteCombine */
01455   if (transport_type == TRANSPORT_ROAD) EndSpriteCombine();
01456 
01457   /* Do not draw anything more if bridges are invisible */
01458   if (IsInvisibilitySet(TO_BRIDGES)) return;
01459 
01460   psid++;
01461   if (ti->z + 5 == z) {
01462     /* draw poles below for small bridges */
01463     if (psid->sprite != 0) {
01464       SpriteID image = psid->sprite;
01465       SpriteID pal   = psid->pal;
01466       if (IsTransparencySet(TO_BRIDGES)) {
01467         SetBit(image, PALETTE_MODIFIER_TRANSPARENT);
01468         pal = PALETTE_TO_TRANSPARENT;
01469       }
01470 
01471       DrawGroundSpriteAt(image, pal, x - ti->x, y - ti->y, z - ti->z);
01472     }
01473   } else {
01474     /* draw pillars below for high bridges */
01475     DrawBridgePillars(psid, ti, axis, drawfarpillar, x, y, z);
01476   }
01477 }
01478 
01479 
01480 static int GetSlopePixelZ_TunnelBridge(TileIndex tile, uint x, uint y)
01481 {
01482   int z;
01483   Slope tileh = GetTilePixelSlope(tile, &z);
01484 
01485   x &= 0xF;
01486   y &= 0xF;
01487 
01488   if (IsTunnel(tile)) {
01489     uint pos = (DiagDirToAxis(GetTunnelBridgeDirection(tile)) == AXIS_X ? y : x);
01490 
01491     /* In the tunnel entrance? */
01492     if (5 <= pos && pos <= 10) return z;
01493   } else { // IsBridge(tile)
01494     DiagDirection dir = GetTunnelBridgeDirection(tile);
01495     uint pos = (DiagDirToAxis(dir) == AXIS_X ? y : x);
01496 
01497     z += ApplyPixelFoundationToSlope(GetBridgeFoundation(tileh, DiagDirToAxis(dir)), &tileh);
01498 
01499     /* On the bridge ramp? */
01500     if (5 <= pos && pos <= 10) {
01501       int delta;
01502 
01503       if (tileh != SLOPE_FLAT) return z + TILE_HEIGHT;
01504 
01505       switch (dir) {
01506         default: NOT_REACHED();
01507         case DIAGDIR_NE: delta = (TILE_SIZE - 1 - x) / 2; break;
01508         case DIAGDIR_SE: delta = y / 2; break;
01509         case DIAGDIR_SW: delta = x / 2; break;
01510         case DIAGDIR_NW: delta = (TILE_SIZE - 1 - y) / 2; break;
01511       }
01512       return z + 1 + delta;
01513     }
01514   }
01515 
01516   return z + GetPartialPixelZ(x, y, tileh);
01517 }
01518 
01519 static Foundation GetFoundation_TunnelBridge(TileIndex tile, Slope tileh)
01520 {
01521   return IsTunnel(tile) ? FOUNDATION_NONE : GetBridgeFoundation(tileh, DiagDirToAxis(GetTunnelBridgeDirection(tile)));
01522 }
01523 
01524 static void GetTileDesc_TunnelBridge(TileIndex tile, TileDesc *td)
01525 {
01526   TransportType tt = GetTunnelBridgeTransportType(tile);
01527 
01528   if (IsTunnel(tile)) {
01529     td->str = (tt == TRANSPORT_RAIL) ? STR_LAI_TUNNEL_DESCRIPTION_RAILROAD : STR_LAI_TUNNEL_DESCRIPTION_ROAD;
01530   } else { // IsBridge(tile)
01531     td->str = (tt == TRANSPORT_WATER) ? STR_LAI_BRIDGE_DESCRIPTION_AQUEDUCT : GetBridgeSpec(GetBridgeType(tile))->transport_name[tt];
01532   }
01533   td->owner[0] = GetTileOwner(tile);
01534 
01535   Owner road_owner = INVALID_OWNER;
01536   Owner tram_owner = INVALID_OWNER;
01537   RoadTypes rts = GetRoadTypes(tile);
01538   if (HasBit(rts, ROADTYPE_ROAD)) road_owner = GetRoadOwner(tile, ROADTYPE_ROAD);
01539   if (HasBit(rts, ROADTYPE_TRAM)) tram_owner = GetRoadOwner(tile, ROADTYPE_TRAM);
01540 
01541   /* Is there a mix of owners? */
01542   if ((tram_owner != INVALID_OWNER && tram_owner != td->owner[0]) ||
01543       (road_owner != INVALID_OWNER && road_owner != td->owner[0])) {
01544     uint i = 1;
01545     if (road_owner != INVALID_OWNER) {
01546       td->owner_type[i] = STR_LAND_AREA_INFORMATION_ROAD_OWNER;
01547       td->owner[i] = road_owner;
01548       i++;
01549     }
01550     if (tram_owner != INVALID_OWNER) {
01551       td->owner_type[i] = STR_LAND_AREA_INFORMATION_TRAM_OWNER;
01552       td->owner[i] = tram_owner;
01553     }
01554   }
01555 
01556   if (tt == TRANSPORT_RAIL) {
01557     const RailtypeInfo *rti = GetRailTypeInfo(GetRailType(tile));
01558     td->rail_speed = rti->max_speed;
01559 
01560     if (!IsTunnel(tile)) {
01561       uint16 spd = GetBridgeSpec(GetBridgeType(tile))->speed;
01562       if (td->rail_speed == 0 || spd < td->rail_speed) {
01563         td->rail_speed = spd;
01564       }
01565     }
01566   } else if (tt == TRANSPORT_ROAD && !IsTunnel(tile)) {
01567     td->road_speed = GetBridgeSpec(GetBridgeType(tile))->speed;
01568   }
01569 }
01570 
01571 
01572 static void TileLoop_TunnelBridge(TileIndex tile)
01573 {
01574   bool snow_or_desert = HasTunnelBridgeSnowOrDesert(tile);
01575   switch (_settings_game.game_creation.landscape) {
01576     case LT_ARCTIC: {
01577       /* As long as we do not have a snow density, we want to use the density
01578        * from the entry edge. For tunnels this is the lowest point for bridges the highest point.
01579        * (Independent of foundations) */
01580       int z = IsBridge(tile) ? GetTileMaxZ(tile) : GetTileZ(tile);
01581       if (snow_or_desert != (z > GetSnowLine())) {
01582         SetTunnelBridgeSnowOrDesert(tile, !snow_or_desert);
01583         MarkTileDirtyByTile(tile);
01584       }
01585       break;
01586     }
01587 
01588     case LT_TROPIC:
01589       if (GetTropicZone(tile) == TROPICZONE_DESERT && !snow_or_desert) {
01590         SetTunnelBridgeSnowOrDesert(tile, true);
01591         MarkTileDirtyByTile(tile);
01592       }
01593       break;
01594 
01595     default:
01596       break;
01597   }
01598 }
01599 
01600 static TrackStatus GetTileTrackStatus_TunnelBridge(TileIndex tile, TransportType mode, uint sub_mode, DiagDirection side)
01601 {
01602   TransportType transport_type = GetTunnelBridgeTransportType(tile);
01603   if (transport_type != mode || (transport_type == TRANSPORT_ROAD && (GetRoadTypes(tile) & sub_mode) == 0)) return 0;
01604 
01605   DiagDirection dir = GetTunnelBridgeDirection(tile);
01606   if (side != INVALID_DIAGDIR && side != ReverseDiagDir(dir)) return 0;
01607   return CombineTrackStatus(TrackBitsToTrackdirBits(DiagDirToDiagTrackBits(dir)), TRACKDIR_BIT_NONE);
01608 }
01609 
01610 static void ChangeTileOwner_TunnelBridge(TileIndex tile, Owner old_owner, Owner new_owner)
01611 {
01612   TileIndex other_end = GetOtherTunnelBridgeEnd(tile);
01613   /* Set number of pieces to zero if it's the southern tile as we
01614    * don't want to update the infrastructure counts twice. */
01615   uint num_pieces = tile < other_end ? (GetTunnelBridgeLength(tile, other_end) + 2) * TUNNELBRIDGE_TRACKBIT_FACTOR : 0;
01616 
01617   for (RoadType rt = ROADTYPE_ROAD; rt < ROADTYPE_END; rt++) {
01618     /* Update all roadtypes, no matter if they are present */
01619     if (GetRoadOwner(tile, rt) == old_owner) {
01620       if (HasBit(GetRoadTypes(tile), rt)) {
01621         /* Update company infrastructure counts. A full diagonal road tile has two road bits.
01622          * No need to dirty windows here, we'll redraw the whole screen anyway. */
01623         Company::Get(old_owner)->infrastructure.road[rt] -= num_pieces * 2;
01624         if (new_owner != INVALID_OWNER) Company::Get(new_owner)->infrastructure.road[rt] += num_pieces * 2;
01625       }
01626 
01627       SetRoadOwner(tile, rt, new_owner == INVALID_OWNER ? OWNER_NONE : new_owner);
01628     }
01629   }
01630 
01631   if (!IsTileOwner(tile, old_owner)) return;
01632 
01633   /* Update company infrastructure counts for rail and water as well.
01634    * No need to dirty windows here, we'll redraw the whole screen anyway. */
01635   TransportType tt = GetTunnelBridgeTransportType(tile);
01636   Company *old = Company::Get(old_owner);
01637   if (tt == TRANSPORT_RAIL) {
01638     old->infrastructure.rail[GetRailType(tile)] -= num_pieces;
01639     if (new_owner != INVALID_OWNER) Company::Get(new_owner)->infrastructure.rail[GetRailType(tile)] += num_pieces;
01640   } else if (tt == TRANSPORT_WATER) {
01641     old->infrastructure.water -= num_pieces;
01642     if (new_owner != INVALID_OWNER) Company::Get(new_owner)->infrastructure.water += num_pieces;
01643   }
01644 
01645   if (new_owner != INVALID_OWNER) {
01646     SetTileOwner(tile, new_owner);
01647   } else {
01648     if (tt == TRANSPORT_RAIL) {
01649       /* Since all of our vehicles have been removed, it is safe to remove the rail
01650        * bridge / tunnel. */
01651       CommandCost ret = DoCommand(tile, 0, 0, DC_EXEC | DC_BANKRUPT, CMD_LANDSCAPE_CLEAR);
01652       assert(ret.Succeeded());
01653     } else {
01654       /* In any other case, we can safely reassign the ownership to OWNER_NONE. */
01655       SetTileOwner(tile, OWNER_NONE);
01656     }
01657   }
01658 }
01659 
01665 static const byte TUNNEL_SOUND_FRAME = 1;
01666 
01675 extern const byte _tunnel_visibility_frame[DIAGDIR_END] = {12, 8, 8, 12};
01676 
01677 static VehicleEnterTileStatus VehicleEnter_TunnelBridge(Vehicle *v, TileIndex tile, int x, int y)
01678 {
01679   int z = GetSlopePixelZ(x, y) - v->z_pos;
01680 
01681   if (abs(z) > 2) return VETSB_CANNOT_ENTER;
01682   /* Direction into the wormhole */
01683   const DiagDirection dir = GetTunnelBridgeDirection(tile);
01684   /* Direction of the vehicle */
01685   const DiagDirection vdir = DirToDiagDir(v->direction);
01686   /* New position of the vehicle on the tile */
01687   byte pos = (DiagDirToAxis(vdir) == AXIS_X ? x : y) & TILE_UNIT_MASK;
01688   /* Number of units moved by the vehicle since entering the tile */
01689   byte frame = (vdir == DIAGDIR_NE || vdir == DIAGDIR_NW) ? TILE_SIZE - 1 - pos : pos;
01690 
01691   if (IsTunnel(tile)) {
01692     if (v->type == VEH_TRAIN) {
01693       Train *t = Train::From(v);
01694 
01695       if (t->track != TRACK_BIT_WORMHOLE && dir == vdir) {
01696         if (t->IsFrontEngine() && frame == TUNNEL_SOUND_FRAME) {
01697           if (!PlayVehicleSound(t, VSE_TUNNEL) && RailVehInfo(t->engine_type)->engclass == 0) {
01698             SndPlayVehicleFx(SND_05_TRAIN_THROUGH_TUNNEL, v);
01699           }
01700           return VETSB_CONTINUE;
01701         }
01702         if (frame == _tunnel_visibility_frame[dir]) {
01703           t->tile = tile;
01704           t->track = TRACK_BIT_WORMHOLE;
01705           t->vehstatus |= VS_HIDDEN;
01706           return VETSB_ENTERED_WORMHOLE;
01707         }
01708       }
01709 
01710       if (dir == ReverseDiagDir(vdir) && frame == TILE_SIZE - _tunnel_visibility_frame[dir] && z == 0) {
01711         /* We're at the tunnel exit ?? */
01712         t->tile = tile;
01713         t->track = DiagDirToDiagTrackBits(vdir);
01714         assert(t->track);
01715         t->vehstatus &= ~VS_HIDDEN;
01716         return VETSB_ENTERED_WORMHOLE;
01717       }
01718     } else if (v->type == VEH_ROAD) {
01719       RoadVehicle *rv = RoadVehicle::From(v);
01720 
01721       /* Enter tunnel? */
01722       if (rv->state != RVSB_WORMHOLE && dir == vdir) {
01723         if (frame == _tunnel_visibility_frame[dir]) {
01724           /* Frame should be equal to the next frame number in the RV's movement */
01725           assert(frame == rv->frame + 1);
01726           rv->tile = tile;
01727           rv->state = RVSB_WORMHOLE;
01728           rv->vehstatus |= VS_HIDDEN;
01729           return VETSB_ENTERED_WORMHOLE;
01730         } else {
01731           return VETSB_CONTINUE;
01732         }
01733       }
01734 
01735       /* We're at the tunnel exit ?? */
01736       if (dir == ReverseDiagDir(vdir) && frame == TILE_SIZE - _tunnel_visibility_frame[dir] && z == 0) {
01737         rv->tile = tile;
01738         rv->state = DiagDirToDiagTrackdir(vdir);
01739         rv->frame = frame;
01740         rv->vehstatus &= ~VS_HIDDEN;
01741         return VETSB_ENTERED_WORMHOLE;
01742       }
01743     }
01744   } else { // IsBridge(tile)
01745     if (v->type != VEH_SHIP) {
01746       /* modify speed of vehicle */
01747       uint16 spd = GetBridgeSpec(GetBridgeType(tile))->speed;
01748 
01749       if (v->type == VEH_ROAD) spd *= 2;
01750       Vehicle *first = v->First();
01751       first->cur_speed = min(first->cur_speed, spd);
01752     }
01753 
01754     if (vdir == dir) {
01755       /* Vehicle enters bridge at the last frame inside this tile. */
01756       if (frame != TILE_SIZE - 1) return VETSB_CONTINUE;
01757       switch (v->type) {
01758         case VEH_TRAIN: {
01759           Train *t = Train::From(v);
01760           t->track = TRACK_BIT_WORMHOLE;
01761           ClrBit(t->gv_flags, GVF_GOINGUP_BIT);
01762           ClrBit(t->gv_flags, GVF_GOINGDOWN_BIT);
01763           break;
01764         }
01765 
01766         case VEH_ROAD: {
01767           RoadVehicle *rv = RoadVehicle::From(v);
01768           rv->state = RVSB_WORMHOLE;
01769           /* There are no slopes inside bridges / tunnels. */
01770           ClrBit(rv->gv_flags, GVF_GOINGUP_BIT);
01771           ClrBit(rv->gv_flags, GVF_GOINGDOWN_BIT);
01772           break;
01773         }
01774 
01775         case VEH_SHIP:
01776           Ship::From(v)->state = TRACK_BIT_WORMHOLE;
01777           break;
01778 
01779         default: NOT_REACHED();
01780       }
01781       return VETSB_ENTERED_WORMHOLE;
01782     } else if (vdir == ReverseDiagDir(dir)) {
01783       v->tile = tile;
01784       switch (v->type) {
01785         case VEH_TRAIN: {
01786           Train *t = Train::From(v);
01787           if (t->track == TRACK_BIT_WORMHOLE) {
01788             t->track = DiagDirToDiagTrackBits(vdir);
01789             return VETSB_ENTERED_WORMHOLE;
01790           }
01791           break;
01792         }
01793 
01794         case VEH_ROAD: {
01795           RoadVehicle *rv = RoadVehicle::From(v);
01796           if (rv->state == RVSB_WORMHOLE) {
01797             rv->state = DiagDirToDiagTrackdir(vdir);
01798             rv->frame = 0;
01799             return VETSB_ENTERED_WORMHOLE;
01800           }
01801           break;
01802         }
01803 
01804         case VEH_SHIP: {
01805           Ship *ship = Ship::From(v);
01806           if (ship->state == TRACK_BIT_WORMHOLE) {
01807             ship->state = DiagDirToDiagTrackBits(vdir);
01808             return VETSB_ENTERED_WORMHOLE;
01809           }
01810           break;
01811         }
01812 
01813         default: NOT_REACHED();
01814       }
01815     }
01816   }
01817   return VETSB_CONTINUE;
01818 }
01819 
01820 static CommandCost TerraformTile_TunnelBridge(TileIndex tile, DoCommandFlag flags, int z_new, Slope tileh_new)
01821 {
01822   if (_settings_game.construction.build_on_slopes && AutoslopeEnabled() && IsBridge(tile) && GetTunnelBridgeTransportType(tile) != TRANSPORT_WATER) {
01823     DiagDirection direction = GetTunnelBridgeDirection(tile);
01824     Axis axis = DiagDirToAxis(direction);
01825     CommandCost res;
01826     int z_old;
01827     Slope tileh_old = GetTileSlope(tile, &z_old);
01828 
01829     /* Check if new slope is valid for bridges in general (so we can safely call GetBridgeFoundation()) */
01830     if ((direction == DIAGDIR_NW) || (direction == DIAGDIR_NE)) {
01831       CheckBridgeSlopeSouth(axis, &tileh_old, &z_old);
01832       res = CheckBridgeSlopeSouth(axis, &tileh_new, &z_new);
01833     } else {
01834       CheckBridgeSlopeNorth(axis, &tileh_old, &z_old);
01835       res = CheckBridgeSlopeNorth(axis, &tileh_new, &z_new);
01836     }
01837 
01838     /* Surface slope is valid and remains unchanged? */
01839     if (res.Succeeded() && (z_old == z_new) && (tileh_old == tileh_new)) return CommandCost(EXPENSES_CONSTRUCTION, _price[PR_BUILD_FOUNDATION]);
01840   }
01841 
01842   return DoCommand(tile, 0, 0, flags, CMD_LANDSCAPE_CLEAR);
01843 }
01844 
01845 extern const TileTypeProcs _tile_type_tunnelbridge_procs = {
01846   DrawTile_TunnelBridge,           // draw_tile_proc
01847   GetSlopePixelZ_TunnelBridge,     // get_slope_z_proc
01848   ClearTile_TunnelBridge,          // clear_tile_proc
01849   NULL,                            // add_accepted_cargo_proc
01850   GetTileDesc_TunnelBridge,        // get_tile_desc_proc
01851   GetTileTrackStatus_TunnelBridge, // get_tile_track_status_proc
01852   NULL,                            // click_tile_proc
01853   NULL,                            // animate_tile_proc
01854   TileLoop_TunnelBridge,           // tile_loop_proc
01855   ChangeTileOwner_TunnelBridge,    // change_tile_owner_proc
01856   NULL,                            // add_produced_cargo_proc
01857   VehicleEnter_TunnelBridge,       // vehicle_enter_tile_proc
01858   GetFoundation_TunnelBridge,      // get_foundation_proc
01859   TerraformTile_TunnelBridge,      // terraform_tile_proc
01860 };