rail_cmd.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 "cmd_helper.h"
00014 #include "viewport_func.h"
00015 #include "command_func.h"
00016 #include "depot_base.h"
00017 #include "pathfinder/yapf/yapf_cache.h"
00018 #include "newgrf_debug.h"
00019 #include "newgrf_railtype.h"
00020 #include "train.h"
00021 #include "autoslope.h"
00022 #include "water.h"
00023 #include "tunnelbridge_map.h"
00024 #include "vehicle_func.h"
00025 #include "sound_func.h"
00026 #include "tunnelbridge.h"
00027 #include "elrail_func.h"
00028 #include "town.h"
00029 #include "pbs.h"
00030 #include "company_base.h"
00031 #include "core/backup_type.hpp"
00032 #include "date_func.h"
00033 #include "strings_func.h"
00034 #include "company_gui.h"
00035 
00036 #include "table/strings.h"
00037 #include "table/railtypes.h"
00038 #include "table/track_land.h"
00039 
00041 typedef SmallVector<Train *, 16> TrainList;
00042 
00043 RailtypeInfo _railtypes[RAILTYPE_END];
00044 
00045 assert_compile(sizeof(_original_railtypes) <= sizeof(_railtypes));
00046 
00048 enum SignalOffsets {
00049   SIGNAL_TO_SOUTHWEST,
00050   SIGNAL_TO_NORTHEAST,
00051   SIGNAL_TO_SOUTHEAST,
00052   SIGNAL_TO_NORTHWEST,
00053   SIGNAL_TO_EAST,
00054   SIGNAL_TO_WEST,
00055   SIGNAL_TO_SOUTH,
00056   SIGNAL_TO_NORTH,
00057 };
00058 
00062 void ResetRailTypes()
00063 {
00064   memset(_railtypes, 0, sizeof(_railtypes));
00065   memcpy(_railtypes, _original_railtypes, sizeof(_original_railtypes));
00066 }
00067 
00068 void ResolveRailTypeGUISprites(RailtypeInfo *rti)
00069 {
00070   SpriteID cursors_base = GetCustomRailSprite(rti, INVALID_TILE, RTSG_CURSORS);
00071   if (cursors_base != 0) {
00072     rti->gui_sprites.build_ns_rail = cursors_base +  0;
00073     rti->gui_sprites.build_x_rail  = cursors_base +  1;
00074     rti->gui_sprites.build_ew_rail = cursors_base +  2;
00075     rti->gui_sprites.build_y_rail  = cursors_base +  3;
00076     rti->gui_sprites.auto_rail     = cursors_base +  4;
00077     rti->gui_sprites.build_depot   = cursors_base +  5;
00078     rti->gui_sprites.build_tunnel  = cursors_base +  6;
00079     rti->gui_sprites.convert_rail  = cursors_base +  7;
00080     rti->cursor.rail_ns   = cursors_base +  8;
00081     rti->cursor.rail_swne = cursors_base +  9;
00082     rti->cursor.rail_ew   = cursors_base + 10;
00083     rti->cursor.rail_nwse = cursors_base + 11;
00084     rti->cursor.autorail  = cursors_base + 12;
00085     rti->cursor.depot     = cursors_base + 13;
00086     rti->cursor.tunnel    = cursors_base + 14;
00087     rti->cursor.convert   = cursors_base + 15;
00088   }
00089 
00090   /* Array of default GUI signal sprite numbers. */
00091   const SpriteID _signal_lookup[2][SIGTYPE_END] = {
00092     {SPR_IMG_SIGNAL_ELECTRIC_NORM,  SPR_IMG_SIGNAL_ELECTRIC_ENTRY, SPR_IMG_SIGNAL_ELECTRIC_EXIT,
00093      SPR_IMG_SIGNAL_ELECTRIC_COMBO, SPR_IMG_SIGNAL_ELECTRIC_PBS,   SPR_IMG_SIGNAL_ELECTRIC_PBS_OWAY},
00094 
00095     {SPR_IMG_SIGNAL_SEMAPHORE_NORM,  SPR_IMG_SIGNAL_SEMAPHORE_ENTRY, SPR_IMG_SIGNAL_SEMAPHORE_EXIT,
00096      SPR_IMG_SIGNAL_SEMAPHORE_COMBO, SPR_IMG_SIGNAL_SEMAPHORE_PBS,   SPR_IMG_SIGNAL_SEMAPHORE_PBS_OWAY},
00097   };
00098 
00099   for (SignalType type = SIGTYPE_NORMAL; type < SIGTYPE_END; type = (SignalType)(type + 1)) {
00100     for (SignalVariant var = SIG_ELECTRIC; var <= SIG_SEMAPHORE; var = (SignalVariant)(var + 1)) {
00101       SpriteID red   = GetCustomSignalSprite(rti, INVALID_TILE, type, var, SIGNAL_STATE_RED, true);
00102       SpriteID green = GetCustomSignalSprite(rti, INVALID_TILE, type, var, SIGNAL_STATE_GREEN, true);
00103       rti->gui_sprites.signals[type][var][0] = (red != 0)   ? red + SIGNAL_TO_SOUTH   : _signal_lookup[var][type];
00104       rti->gui_sprites.signals[type][var][1] = (green != 0) ? green + SIGNAL_TO_SOUTH : _signal_lookup[var][type] + 1;
00105     }
00106   }
00107 }
00108 
00112 void InitRailTypes()
00113 {
00114   for (RailType rt = RAILTYPE_BEGIN; rt != RAILTYPE_END; rt++) {
00115     RailtypeInfo *rti = &_railtypes[rt];
00116     ResolveRailTypeGUISprites(rti);
00117   }
00118 }
00119 
00123 RailType AllocateRailType(RailTypeLabel label)
00124 {
00125   for (RailType rt = RAILTYPE_BEGIN; rt != RAILTYPE_END; rt++) {
00126     RailtypeInfo *rti = &_railtypes[rt];
00127 
00128     if (rti->label == 0) {
00129       /* Set up new rail type */
00130       memcpy(rti, &_railtypes[RAILTYPE_RAIL], sizeof(*rti));
00131       rti->label = label;
00132       /* Clear alternate label list. Can't use Reset() here as that would free
00133        * the data pointer of RAILTYPE_RAIL and not our new rail type. */
00134       new (&rti->alternate_labels) RailTypeLabelList;
00135 
00136       /* Make us compatible with ourself. */
00137       rti->powered_railtypes    = (RailTypes)(1 << rt);
00138       rti->compatible_railtypes = (RailTypes)(1 << rt);
00139 
00140       /* We also introduce ourself. */
00141       rti->introduces_railtypes = (RailTypes)(1 << rt);
00142 
00143       /* Default sort order; order of allocation, but with some
00144        * offsets so it's easier for NewGRF to pick a spot without
00145        * changing the order of other (original) rail types.
00146        * The << is so you can place other railtypes in between the
00147        * other railtypes, the 7 is to be able to place something
00148        * before the first (default) rail type. */
00149       rti->sorting_order = rt << 4 | 7;
00150       return rt;
00151     }
00152   }
00153 
00154   return INVALID_RAILTYPE;
00155 }
00156 
00157 static const byte _track_sloped_sprites[14] = {
00158   14, 15, 22, 13,
00159    0, 21, 17, 12,
00160   23,  0, 18, 20,
00161   19, 16
00162 };
00163 
00164 
00165 /*         4
00166  *     ---------
00167  *    |\       /|
00168  *    | \    1/ |
00169  *    |  \   /  |
00170  *    |   \ /   |
00171  *  16|    \    |32
00172  *    |   / \2  |
00173  *    |  /   \  |
00174  *    | /     \ |
00175  *    |/       \|
00176  *     ---------
00177  *         8
00178  */
00179 
00180 
00181 
00182 /* MAP2 byte:    abcd???? => Signal On? Same coding as map3lo
00183  * MAP3LO byte:  abcd???? => Signal Exists?
00184  *               a and b are for diagonals, upper and left,
00185  *               one for each direction. (ie a == NE->SW, b ==
00186  *               SW->NE, or v.v., I don't know. b and c are
00187  *               similar for lower and right.
00188  * MAP2 byte:    ????abcd => Type of ground.
00189  * MAP3LO byte:  ????abcd => Type of rail.
00190  * MAP5:         00abcdef => rail
00191  *               01abcdef => rail w/ signals
00192  *               10uuuuuu => unused
00193  *               11uuuudd => rail depot
00194  */
00195 
00204 static CommandCost EnsureNoTrainOnTrack(TileIndex tile, Track track)
00205 {
00206   TrackBits rail_bits = TrackToTrackBits(track);
00207   return EnsureNoTrainOnTrackBits(tile, rail_bits);
00208 }
00209 
00217 static CommandCost CheckTrackCombination(TileIndex tile, TrackBits to_build, uint flags)
00218 {
00219   if (!IsPlainRail(tile)) return_cmd_error(STR_ERROR_IMPOSSIBLE_TRACK_COMBINATION);
00220 
00221   /* So, we have a tile with tracks on it (and possibly signals). Let's see
00222    * what tracks first */
00223   TrackBits current = GetTrackBits(tile); // The current track layout.
00224   TrackBits future = current | to_build;  // The track layout we want to build.
00225 
00226   /* Are we really building something new? */
00227   if (current == future) {
00228     /* Nothing new is being built */
00229     return_cmd_error(STR_ERROR_ALREADY_BUILT);
00230   }
00231 
00232   /* Let's see if we may build this */
00233   if ((flags & DC_NO_RAIL_OVERLAP) || HasSignals(tile)) {
00234     /* If we are not allowed to overlap (flag is on for ai companies or we have
00235      * signals on the tile), check that */
00236     if (future != TRACK_BIT_HORZ && future != TRACK_BIT_VERT) {
00237       return_cmd_error((flags & DC_NO_RAIL_OVERLAP) ? STR_ERROR_IMPOSSIBLE_TRACK_COMBINATION : STR_ERROR_MUST_REMOVE_SIGNALS_FIRST);
00238     }
00239   }
00240   /* Normally, we may overlap and any combination is valid */
00241   return CommandCost();
00242 }
00243 
00244 
00246 static const TrackBits _valid_tracks_without_foundation[15] = {
00247   TRACK_BIT_ALL,
00248   TRACK_BIT_RIGHT,
00249   TRACK_BIT_UPPER,
00250   TRACK_BIT_X,
00251 
00252   TRACK_BIT_LEFT,
00253   TRACK_BIT_NONE,
00254   TRACK_BIT_Y,
00255   TRACK_BIT_LOWER,
00256 
00257   TRACK_BIT_LOWER,
00258   TRACK_BIT_Y,
00259   TRACK_BIT_NONE,
00260   TRACK_BIT_LEFT,
00261 
00262   TRACK_BIT_X,
00263   TRACK_BIT_UPPER,
00264   TRACK_BIT_RIGHT,
00265 };
00266 
00268 static const TrackBits _valid_tracks_on_leveled_foundation[15] = {
00269   TRACK_BIT_NONE,
00270   TRACK_BIT_LEFT,
00271   TRACK_BIT_LOWER,
00272   TRACK_BIT_Y | TRACK_BIT_LOWER | TRACK_BIT_LEFT,
00273 
00274   TRACK_BIT_RIGHT,
00275   TRACK_BIT_ALL,
00276   TRACK_BIT_X | TRACK_BIT_LOWER | TRACK_BIT_RIGHT,
00277   TRACK_BIT_ALL,
00278 
00279   TRACK_BIT_UPPER,
00280   TRACK_BIT_X | TRACK_BIT_UPPER | TRACK_BIT_LEFT,
00281   TRACK_BIT_ALL,
00282   TRACK_BIT_ALL,
00283 
00284   TRACK_BIT_Y | TRACK_BIT_UPPER | TRACK_BIT_RIGHT,
00285   TRACK_BIT_ALL,
00286   TRACK_BIT_ALL
00287 };
00288 
00296 Foundation GetRailFoundation(Slope tileh, TrackBits bits)
00297 {
00298   if (bits == TRACK_BIT_NONE) return FOUNDATION_NONE;
00299 
00300   if (IsSteepSlope(tileh)) {
00301     /* Test for inclined foundations */
00302     if (bits == TRACK_BIT_X) return FOUNDATION_INCLINED_X;
00303     if (bits == TRACK_BIT_Y) return FOUNDATION_INCLINED_Y;
00304 
00305     /* Get higher track */
00306     Corner highest_corner = GetHighestSlopeCorner(tileh);
00307     TrackBits higher_track = CornerToTrackBits(highest_corner);
00308 
00309     /* Only higher track? */
00310     if (bits == higher_track) return HalftileFoundation(highest_corner);
00311 
00312     /* Overlap with higher track? */
00313     if (TracksOverlap(bits | higher_track)) return FOUNDATION_INVALID;
00314 
00315     /* either lower track or both higher and lower track */
00316     return ((bits & higher_track) != 0 ? FOUNDATION_STEEP_BOTH : FOUNDATION_STEEP_LOWER);
00317   } else {
00318     if ((~_valid_tracks_without_foundation[tileh] & bits) == 0) return FOUNDATION_NONE;
00319 
00320     bool valid_on_leveled = ((~_valid_tracks_on_leveled_foundation[tileh] & bits) == 0);
00321 
00322     Corner track_corner;
00323     switch (bits) {
00324       case TRACK_BIT_LEFT:  track_corner = CORNER_W; break;
00325       case TRACK_BIT_LOWER: track_corner = CORNER_S; break;
00326       case TRACK_BIT_RIGHT: track_corner = CORNER_E; break;
00327       case TRACK_BIT_UPPER: track_corner = CORNER_N; break;
00328 
00329       case TRACK_BIT_HORZ:
00330         if (tileh == SLOPE_N) return HalftileFoundation(CORNER_N);
00331         if (tileh == SLOPE_S) return HalftileFoundation(CORNER_S);
00332         return (valid_on_leveled ? FOUNDATION_LEVELED : FOUNDATION_INVALID);
00333 
00334       case TRACK_BIT_VERT:
00335         if (tileh == SLOPE_W) return HalftileFoundation(CORNER_W);
00336         if (tileh == SLOPE_E) return HalftileFoundation(CORNER_E);
00337         return (valid_on_leveled ? FOUNDATION_LEVELED : FOUNDATION_INVALID);
00338 
00339       case TRACK_BIT_X:
00340         if (IsSlopeWithOneCornerRaised(tileh)) return FOUNDATION_INCLINED_X;
00341         return (valid_on_leveled ? FOUNDATION_LEVELED : FOUNDATION_INVALID);
00342 
00343       case TRACK_BIT_Y:
00344         if (IsSlopeWithOneCornerRaised(tileh)) return FOUNDATION_INCLINED_Y;
00345         return (valid_on_leveled ? FOUNDATION_LEVELED : FOUNDATION_INVALID);
00346 
00347       default:
00348         return (valid_on_leveled ? FOUNDATION_LEVELED : FOUNDATION_INVALID);
00349     }
00350     /* Single diagonal track */
00351 
00352     /* Track must be at least valid on leveled foundation */
00353     if (!valid_on_leveled) return FOUNDATION_INVALID;
00354 
00355     /* If slope has three raised corners, build leveled foundation */
00356     if (IsSlopeWithThreeCornersRaised(tileh)) return FOUNDATION_LEVELED;
00357 
00358     /* If neighboured corners of track_corner are lowered, build halftile foundation */
00359     if ((tileh & SlopeWithThreeCornersRaised(OppositeCorner(track_corner))) == SlopeWithOneCornerRaised(track_corner)) return HalftileFoundation(track_corner);
00360 
00361     /* else special anti-zig-zag foundation */
00362     return SpecialRailFoundation(track_corner);
00363   }
00364 }
00365 
00366 
00376 static CommandCost CheckRailSlope(Slope tileh, TrackBits rail_bits, TrackBits existing, TileIndex tile)
00377 {
00378   /* don't allow building on the lower side of a coast */
00379   if (GetFloodingBehaviour(tile) != FLOOD_NONE) {
00380     if (!IsSteepSlope(tileh) && ((~_valid_tracks_on_leveled_foundation[tileh] & (rail_bits | existing)) != 0)) return_cmd_error(STR_ERROR_CAN_T_BUILD_ON_WATER);
00381   }
00382 
00383   Foundation f_new = GetRailFoundation(tileh, rail_bits | existing);
00384 
00385   /* check track/slope combination */
00386   if ((f_new == FOUNDATION_INVALID) ||
00387       ((f_new != FOUNDATION_NONE) && (!_settings_game.construction.build_on_slopes))) {
00388     return_cmd_error(STR_ERROR_LAND_SLOPED_IN_WRONG_DIRECTION);
00389   }
00390 
00391   Foundation f_old = GetRailFoundation(tileh, existing);
00392   return CommandCost(EXPENSES_CONSTRUCTION, f_new != f_old ? _price[PR_BUILD_FOUNDATION] : (Money)0);
00393 }
00394 
00395 /* Validate functions for rail building */
00396 static inline bool ValParamTrackOrientation(Track track)
00397 {
00398   return IsValidTrack(track);
00399 }
00400 
00410 CommandCost CmdBuildSingleRail(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
00411 {
00412   RailType railtype = Extract<RailType, 0, 4>(p1);
00413   Track track = Extract<Track, 0, 3>(p2);
00414   CommandCost cost(EXPENSES_CONSTRUCTION);
00415 
00416   if (!ValParamRailtype(railtype) || !ValParamTrackOrientation(track)) return CMD_ERROR;
00417 
00418   Slope tileh = GetTileSlope(tile);
00419   TrackBits trackbit = TrackToTrackBits(track);
00420 
00421   switch (GetTileType(tile)) {
00422     case MP_RAILWAY: {
00423       CommandCost ret = CheckTileOwnership(tile);
00424       if (ret.Failed()) return ret;
00425 
00426       if (!IsPlainRail(tile)) return CMD_ERROR;
00427 
00428       if (!IsCompatibleRail(GetRailType(tile), railtype)) return_cmd_error(STR_ERROR_IMPOSSIBLE_TRACK_COMBINATION);
00429 
00430       ret = CheckTrackCombination(tile, trackbit, flags);
00431       if (ret.Succeeded()) ret = EnsureNoTrainOnTrack(tile, track);
00432       if (ret.Failed()) return ret;
00433 
00434       ret = CheckRailSlope(tileh, trackbit, GetTrackBits(tile), tile);
00435       if (ret.Failed()) return ret;
00436       cost.AddCost(ret);
00437 
00438       /* If the rail types don't match, try to convert only if engines of
00439        * the new rail type are not powered on the present rail type and engines of
00440        * the present rail type are powered on the new rail type. */
00441       if (GetRailType(tile) != railtype && !HasPowerOnRail(railtype, GetRailType(tile))) {
00442         if (HasPowerOnRail(GetRailType(tile), railtype)) {
00443           ret = DoCommand(tile, tile, railtype, flags, CMD_CONVERT_RAIL);
00444           if (ret.Failed()) return ret;
00445           cost.AddCost(ret);
00446         } else {
00447           return CMD_ERROR;
00448         }
00449       }
00450 
00451       if (flags & DC_EXEC) {
00452         SetRailGroundType(tile, RAIL_GROUND_BARREN);
00453         TrackBits bits = GetTrackBits(tile);
00454         SetTrackBits(tile, bits | trackbit);
00455         /* Subtract old infrastructure count. */
00456         uint pieces = CountBits(bits);
00457         if (TracksOverlap(bits)) pieces *= pieces;
00458         Company::Get(GetTileOwner(tile))->infrastructure.rail[GetRailType(tile)] -= pieces;
00459         /* Add new infrastructure count. */
00460         pieces = CountBits(bits | trackbit);
00461         if (TracksOverlap(bits | trackbit)) pieces *= pieces;
00462         Company::Get(GetTileOwner(tile))->infrastructure.rail[GetRailType(tile)] += pieces;
00463         DirtyCompanyInfrastructureWindows(GetTileOwner(tile));
00464       }
00465       break;
00466     }
00467 
00468     case MP_ROAD: {
00469       /* Level crossings may only be built on these slopes */
00470       if (!HasBit(VALID_LEVEL_CROSSING_SLOPES, tileh)) return_cmd_error(STR_ERROR_LAND_SLOPED_IN_WRONG_DIRECTION);
00471 
00472       CommandCost ret = EnsureNoVehicleOnGround(tile);
00473       if (ret.Failed()) return ret;
00474 
00475       if (IsNormalRoad(tile)) {
00476         if (HasRoadWorks(tile)) return_cmd_error(STR_ERROR_ROAD_WORKS_IN_PROGRESS);
00477 
00478         if (GetDisallowedRoadDirections(tile) != DRD_NONE) return_cmd_error(STR_ERROR_CROSSING_ON_ONEWAY_ROAD);
00479 
00480         if (RailNoLevelCrossings(railtype)) return_cmd_error(STR_ERROR_CROSSING_DISALLOWED);
00481 
00482         RoadTypes roadtypes = GetRoadTypes(tile);
00483         RoadBits road = GetRoadBits(tile, ROADTYPE_ROAD);
00484         RoadBits tram = GetRoadBits(tile, ROADTYPE_TRAM);
00485         switch (roadtypes) {
00486           default: break;
00487           case ROADTYPES_TRAM:
00488             /* Tram crossings must always have road. */
00489             if (flags & DC_EXEC) {
00490               SetRoadOwner(tile, ROADTYPE_ROAD, _current_company);
00491               Company *c = Company::GetIfValid(_current_company);
00492               if (c != NULL) {
00493                 /* A full diagonal tile has two road bits. */
00494                 c->infrastructure.road[ROADTYPE_ROAD] += 2;
00495                 DirtyCompanyInfrastructureWindows(c->index);
00496               }
00497             }
00498             roadtypes |= ROADTYPES_ROAD;
00499             break;
00500 
00501           case ROADTYPES_ALL:
00502             if (road != tram) return CMD_ERROR;
00503             break;
00504         }
00505 
00506         road |= tram;
00507 
00508         if ((track == TRACK_X && road == ROAD_Y) ||
00509             (track == TRACK_Y && road == ROAD_X)) {
00510           if (flags & DC_EXEC) {
00511             MakeRoadCrossing(tile, GetRoadOwner(tile, ROADTYPE_ROAD), GetRoadOwner(tile, ROADTYPE_TRAM), _current_company, (track == TRACK_X ? AXIS_Y : AXIS_X), railtype, roadtypes, GetTownIndex(tile));
00512             UpdateLevelCrossing(tile, false);
00513             Company::Get(_current_company)->infrastructure.rail[railtype] += LEVELCROSSING_TRACKBIT_FACTOR;
00514             DirtyCompanyInfrastructureWindows(_current_company);
00515           }
00516           break;
00517         }
00518       }
00519 
00520       if (IsLevelCrossing(tile) && GetCrossingRailBits(tile) == trackbit) {
00521         return_cmd_error(STR_ERROR_ALREADY_BUILT);
00522       }
00523       /* FALL THROUGH */
00524     }
00525 
00526     default: {
00527       /* Will there be flat water on the lower halftile? */
00528       bool water_ground = IsTileType(tile, MP_WATER) && IsSlopeWithOneCornerRaised(tileh);
00529 
00530       CommandCost ret = CheckRailSlope(tileh, trackbit, TRACK_BIT_NONE, tile);
00531       if (ret.Failed()) return ret;
00532       cost.AddCost(ret);
00533 
00534       ret = DoCommand(tile, 0, 0, flags, CMD_LANDSCAPE_CLEAR);
00535       if (ret.Failed()) return ret;
00536       cost.AddCost(ret);
00537 
00538       if (water_ground) {
00539         cost.AddCost(-_price[PR_CLEAR_WATER]);
00540         cost.AddCost(_price[PR_CLEAR_ROUGH]);
00541       }
00542 
00543       if (flags & DC_EXEC) {
00544         MakeRailNormal(tile, _current_company, trackbit, railtype);
00545         if (water_ground) SetRailGroundType(tile, RAIL_GROUND_WATER);
00546         Company::Get(_current_company)->infrastructure.rail[railtype]++;
00547         DirtyCompanyInfrastructureWindows(_current_company);
00548       }
00549       break;
00550     }
00551   }
00552 
00553   if (flags & DC_EXEC) {
00554     MarkTileDirtyByTile(tile);
00555     AddTrackToSignalBuffer(tile, track, _current_company);
00556     YapfNotifyTrackLayoutChange(tile, track);
00557   }
00558 
00559   cost.AddCost(RailBuildCost(railtype));
00560   return cost;
00561 }
00562 
00572 CommandCost CmdRemoveSingleRail(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
00573 {
00574   Track track = Extract<Track, 0, 3>(p2);
00575   CommandCost cost(EXPENSES_CONSTRUCTION);
00576   bool crossing = false;
00577 
00578   if (!ValParamTrackOrientation(track)) return CMD_ERROR;
00579   TrackBits trackbit = TrackToTrackBits(track);
00580 
00581   /* Need to read tile owner now because it may change when the rail is removed
00582    * Also, in case of floods, _current_company != owner
00583    * There may be invalid tiletype even in exec run (when removing long track),
00584    * so do not call GetTileOwner(tile) in any case here */
00585   Owner owner = INVALID_OWNER;
00586 
00587   Train *v = NULL;
00588 
00589   switch (GetTileType(tile)) {
00590     case MP_ROAD: {
00591       if (!IsLevelCrossing(tile) || GetCrossingRailBits(tile) != trackbit) return_cmd_error(STR_ERROR_THERE_IS_NO_RAILROAD_TRACK);
00592 
00593       if (_current_company != OWNER_WATER) {
00594         CommandCost ret = CheckTileOwnership(tile);
00595         if (ret.Failed()) return ret;
00596       }
00597 
00598       if (!(flags & DC_BANKRUPT)) {
00599         CommandCost ret = EnsureNoVehicleOnGround(tile);
00600         if (ret.Failed()) return ret;
00601       }
00602 
00603       cost.AddCost(RailClearCost(GetRailType(tile)));
00604 
00605       if (flags & DC_EXEC) {
00606         if (HasReservedTracks(tile, trackbit)) {
00607           v = GetTrainForReservation(tile, track);
00608           if (v != NULL) FreeTrainTrackReservation(v);
00609         }
00610         owner = GetTileOwner(tile);
00611         Company::Get(owner)->infrastructure.rail[GetRailType(tile)] -= LEVELCROSSING_TRACKBIT_FACTOR;
00612         DirtyCompanyInfrastructureWindows(owner);
00613         MakeRoadNormal(tile, GetCrossingRoadBits(tile), GetRoadTypes(tile), GetTownIndex(tile), GetRoadOwner(tile, ROADTYPE_ROAD), GetRoadOwner(tile, ROADTYPE_TRAM));
00614         DeleteNewGRFInspectWindow(GSF_RAILTYPES, tile);
00615       }
00616       break;
00617     }
00618 
00619     case MP_RAILWAY: {
00620       TrackBits present;
00621       /* There are no rails present at depots. */
00622       if (!IsPlainRail(tile)) return_cmd_error(STR_ERROR_THERE_IS_NO_RAILROAD_TRACK);
00623 
00624       if (_current_company != OWNER_WATER) {
00625         CommandCost ret = CheckTileOwnership(tile);
00626         if (ret.Failed()) return ret;
00627       }
00628 
00629       CommandCost ret = EnsureNoTrainOnTrack(tile, track);
00630       if (ret.Failed()) return ret;
00631 
00632       present = GetTrackBits(tile);
00633       if ((present & trackbit) == 0) return_cmd_error(STR_ERROR_THERE_IS_NO_RAILROAD_TRACK);
00634       if (present == (TRACK_BIT_X | TRACK_BIT_Y)) crossing = true;
00635 
00636       cost.AddCost(RailClearCost(GetRailType(tile)));
00637 
00638       /* Charge extra to remove signals on the track, if they are there */
00639       if (HasSignalOnTrack(tile, track)) {
00640         cost.AddCost(DoCommand(tile, track, 0, flags, CMD_REMOVE_SIGNALS));
00641       }
00642 
00643       if (flags & DC_EXEC) {
00644         if (HasReservedTracks(tile, trackbit)) {
00645           v = GetTrainForReservation(tile, track);
00646           if (v != NULL) FreeTrainTrackReservation(v);
00647         }
00648 
00649         owner = GetTileOwner(tile);
00650 
00651         /* Subtract old infrastructure count. */
00652         uint pieces = CountBits(present);
00653         if (TracksOverlap(present)) pieces *= pieces;
00654         Company::Get(owner)->infrastructure.rail[GetRailType(tile)] -= pieces;
00655         /* Add new infrastructure count. */
00656         present ^= trackbit;
00657         pieces = CountBits(present);
00658         if (TracksOverlap(present)) pieces *= pieces;
00659         Company::Get(owner)->infrastructure.rail[GetRailType(tile)] += pieces;
00660         DirtyCompanyInfrastructureWindows(owner);
00661 
00662         if (present == 0) {
00663           Slope tileh = GetTileSlope(tile);
00664           /* If there is flat water on the lower halftile, convert the tile to shore so the water remains */
00665           if (GetRailGroundType(tile) == RAIL_GROUND_WATER && IsSlopeWithOneCornerRaised(tileh)) {
00666             MakeShore(tile);
00667           } else {
00668             DoClearSquare(tile);
00669           }
00670           DeleteNewGRFInspectWindow(GSF_RAILTYPES, tile);
00671         } else {
00672           SetTrackBits(tile, present);
00673           SetTrackReservation(tile, GetRailReservationTrackBits(tile) & present);
00674         }
00675       }
00676       break;
00677     }
00678 
00679     default: return_cmd_error(STR_ERROR_THERE_IS_NO_RAILROAD_TRACK);
00680   }
00681 
00682   if (flags & DC_EXEC) {
00683     /* if we got that far, 'owner' variable is set correctly */
00684     assert(Company::IsValidID(owner));
00685 
00686     MarkTileDirtyByTile(tile);
00687     if (crossing) {
00688       /* crossing is set when only TRACK_BIT_X and TRACK_BIT_Y are set. As we
00689        * are removing one of these pieces, we'll need to update signals for
00690        * both directions explicitly, as after the track is removed it won't
00691        * 'connect' with the other piece. */
00692       AddTrackToSignalBuffer(tile, TRACK_X, owner);
00693       AddTrackToSignalBuffer(tile, TRACK_Y, owner);
00694       YapfNotifyTrackLayoutChange(tile, TRACK_X);
00695       YapfNotifyTrackLayoutChange(tile, TRACK_Y);
00696     } else {
00697       AddTrackToSignalBuffer(tile, track, owner);
00698       YapfNotifyTrackLayoutChange(tile, track);
00699     }
00700 
00701     if (v != NULL) TryPathReserve(v, true);
00702   }
00703 
00704   return cost;
00705 }
00706 
00707 
00715 bool FloodHalftile(TileIndex t)
00716 {
00717   assert(IsPlainRailTile(t));
00718 
00719   bool flooded = false;
00720   if (GetRailGroundType(t) == RAIL_GROUND_WATER) return flooded;
00721 
00722   Slope tileh = GetTileSlope(t);
00723   TrackBits rail_bits = GetTrackBits(t);
00724 
00725   if (IsSlopeWithOneCornerRaised(tileh)) {
00726     TrackBits lower_track = CornerToTrackBits(OppositeCorner(GetHighestSlopeCorner(tileh)));
00727 
00728     TrackBits to_remove = lower_track & rail_bits;
00729     if (to_remove != 0) {
00730       Backup<CompanyByte> cur_company(_current_company, OWNER_WATER, FILE_LINE);
00731       flooded = DoCommand(t, 0, FIND_FIRST_BIT(to_remove), DC_EXEC, CMD_REMOVE_SINGLE_RAIL).Succeeded();
00732       cur_company.Restore();
00733       if (!flooded) return flooded; // not yet floodable
00734       rail_bits = rail_bits & ~to_remove;
00735       if (rail_bits == 0) {
00736         MakeShore(t);
00737         MarkTileDirtyByTile(t);
00738         return flooded;
00739       }
00740     }
00741 
00742     if (IsNonContinuousFoundation(GetRailFoundation(tileh, rail_bits))) {
00743       flooded = true;
00744       SetRailGroundType(t, RAIL_GROUND_WATER);
00745       MarkTileDirtyByTile(t);
00746     }
00747   } else {
00748     /* Make shore on steep slopes and 'three-corners-raised'-slopes. */
00749     if (ApplyFoundationToSlope(GetRailFoundation(tileh, rail_bits), &tileh) == 0) {
00750       if (IsSteepSlope(tileh) || IsSlopeWithThreeCornersRaised(tileh)) {
00751         flooded = true;
00752         SetRailGroundType(t, RAIL_GROUND_WATER);
00753         MarkTileDirtyByTile(t);
00754       }
00755     }
00756   }
00757   return flooded;
00758 }
00759 
00760 static const TileIndexDiffC _trackdelta[] = {
00761   { -1,  0 }, {  0,  1 }, { -1,  0 }, {  0,  1 }, {  1,  0 }, {  0,  1 },
00762   {  0,  0 },
00763   {  0,  0 },
00764   {  1,  0 }, {  0, -1 }, {  0, -1 }, {  1,  0 }, {  0, -1 }, { -1,  0 },
00765   {  0,  0 },
00766   {  0,  0 }
00767 };
00768 
00769 
00770 static CommandCost ValidateAutoDrag(Trackdir *trackdir, TileIndex start, TileIndex end)
00771 {
00772   int x = TileX(start);
00773   int y = TileY(start);
00774   int ex = TileX(end);
00775   int ey = TileY(end);
00776 
00777   if (!ValParamTrackOrientation(TrackdirToTrack(*trackdir))) return CMD_ERROR;
00778 
00779   /* calculate delta x,y from start to end tile */
00780   int dx = ex - x;
00781   int dy = ey - y;
00782 
00783   /* calculate delta x,y for the first direction */
00784   int trdx = _trackdelta[*trackdir].x;
00785   int trdy = _trackdelta[*trackdir].y;
00786 
00787   if (!IsDiagonalTrackdir(*trackdir)) {
00788     trdx += _trackdelta[*trackdir ^ 1].x;
00789     trdy += _trackdelta[*trackdir ^ 1].y;
00790   }
00791 
00792   /* validate the direction */
00793   while ((trdx <= 0 && dx > 0) ||
00794       (trdx >= 0 && dx < 0) ||
00795       (trdy <= 0 && dy > 0) ||
00796       (trdy >= 0 && dy < 0)) {
00797     if (!HasBit(*trackdir, 3)) { // first direction is invalid, try the other
00798       SetBit(*trackdir, 3); // reverse the direction
00799       trdx = -trdx;
00800       trdy = -trdy;
00801     } else { // other direction is invalid too, invalid drag
00802       return CMD_ERROR;
00803     }
00804   }
00805 
00806   /* (for diagonal tracks, this is already made sure of by above test), but:
00807    * for non-diagonal tracks, check if the start and end tile are on 1 line */
00808   if (!IsDiagonalTrackdir(*trackdir)) {
00809     trdx = _trackdelta[*trackdir].x;
00810     trdy = _trackdelta[*trackdir].y;
00811     if (abs(dx) != abs(dy) && abs(dx) + abs(trdy) != abs(dy) + abs(trdx)) return CMD_ERROR;
00812   }
00813 
00814   return CommandCost();
00815 }
00816 
00830 static CommandCost CmdRailTrackHelper(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
00831 {
00832   CommandCost total_cost(EXPENSES_CONSTRUCTION);
00833   Track track = Extract<Track, 4, 3>(p2);
00834   bool remove = HasBit(p2, 7);
00835   RailType railtype = Extract<RailType, 0, 4>(p2);
00836 
00837   if (!ValParamRailtype(railtype) || !ValParamTrackOrientation(track)) return CMD_ERROR;
00838   if (p1 >= MapSize()) return CMD_ERROR;
00839   TileIndex end_tile = p1;
00840   Trackdir trackdir = TrackToTrackdir(track);
00841 
00842   CommandCost ret = ValidateAutoDrag(&trackdir, tile, end_tile);
00843   if (ret.Failed()) return ret;
00844 
00845   if ((flags & DC_EXEC) && _settings_client.sound.confirm) SndPlayTileFx(SND_20_SPLAT_2, tile);
00846 
00847   bool had_success = false;
00848   CommandCost last_error = CMD_ERROR;
00849   for (;;) {
00850     CommandCost ret = DoCommand(tile, railtype, TrackdirToTrack(trackdir), flags, remove ? CMD_REMOVE_SINGLE_RAIL : CMD_BUILD_SINGLE_RAIL);
00851 
00852     if (ret.Failed()) {
00853       last_error = ret;
00854       if (last_error.GetErrorMessage() != STR_ERROR_ALREADY_BUILT && !remove) {
00855         if (HasBit(p2, 8)) return last_error;
00856         break;
00857       }
00858 
00859       /* Ownership errors are more important. */
00860       if (last_error.GetErrorMessage() == STR_ERROR_OWNED_BY && remove) break;
00861     } else {
00862       had_success = true;
00863       total_cost.AddCost(ret);
00864     }
00865 
00866     if (tile == end_tile) break;
00867 
00868     tile += ToTileIndexDiff(_trackdelta[trackdir]);
00869 
00870     /* toggle railbit for the non-diagonal tracks */
00871     if (!IsDiagonalTrackdir(trackdir)) ToggleBit(trackdir, 0);
00872   }
00873 
00874   if (had_success) return total_cost;
00875   return last_error;
00876 }
00877 
00892 CommandCost CmdBuildRailroadTrack(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
00893 {
00894   return CmdRailTrackHelper(tile, flags, p1, ClrBit(p2, 7), text);
00895 }
00896 
00911 CommandCost CmdRemoveRailroadTrack(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
00912 {
00913   return CmdRailTrackHelper(tile, flags, p1, SetBit(p2, 7), text);
00914 }
00915 
00928 CommandCost CmdBuildTrainDepot(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
00929 {
00930   /* check railtype and valid direction for depot (0 through 3), 4 in total */
00931   RailType railtype = Extract<RailType, 0, 4>(p1);
00932   if (!ValParamRailtype(railtype)) return CMD_ERROR;
00933 
00934   Slope tileh = GetTileSlope(tile);
00935 
00936   DiagDirection dir = Extract<DiagDirection, 0, 2>(p2);
00937 
00938   /* Prohibit construction if
00939    * The tile is non-flat AND
00940    * 1) build-on-slopes is disabled
00941    * 2) the tile is steep i.e. spans two height levels
00942    * 3) the exit points in the wrong direction
00943    */
00944 
00945   if (tileh != SLOPE_FLAT && (
00946         !_settings_game.construction.build_on_slopes ||
00947         !CanBuildDepotByTileh(dir, tileh)
00948       )) {
00949     return_cmd_error(STR_ERROR_FLAT_LAND_REQUIRED);
00950   }
00951 
00952   CommandCost cost = DoCommand(tile, 0, 0, flags, CMD_LANDSCAPE_CLEAR);
00953   if (cost.Failed()) return cost;
00954 
00955   if (MayHaveBridgeAbove(tile) && IsBridgeAbove(tile)) return_cmd_error(STR_ERROR_MUST_DEMOLISH_BRIDGE_FIRST);
00956 
00957   if (!Depot::CanAllocateItem()) return CMD_ERROR;
00958 
00959   if (flags & DC_EXEC) {
00960     Depot *d = new Depot(tile);
00961     d->build_date = _date;
00962 
00963     MakeRailDepot(tile, _current_company, d->index, dir, railtype);
00964     MarkTileDirtyByTile(tile);
00965     MakeDefaultName(d);
00966 
00967     Company::Get(_current_company)->infrastructure.rail[railtype]++;
00968     DirtyCompanyInfrastructureWindows(_current_company);
00969 
00970     AddSideToSignalBuffer(tile, INVALID_DIAGDIR, _current_company);
00971     YapfNotifyTrackLayoutChange(tile, DiagDirToDiagTrack(dir));
00972   }
00973 
00974   cost.AddCost(_price[PR_BUILD_DEPOT_TRAIN]);
00975   cost.AddCost(RailBuildCost(railtype));
00976   return cost;
00977 }
00978 
01000 CommandCost CmdBuildSingleSignal(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
01001 {
01002   Track track = Extract<Track, 0, 3>(p1);
01003   bool ctrl_pressed = HasBit(p1, 3); // was the CTRL button pressed
01004   SignalVariant sigvar = (ctrl_pressed ^ HasBit(p1, 4)) ? SIG_SEMAPHORE : SIG_ELECTRIC; // the signal variant of the new signal
01005   SignalType sigtype = Extract<SignalType, 5, 3>(p1); // the signal type of the new signal
01006   bool convert_signal = HasBit(p1, 8); // convert button pressed
01007   SignalType cycle_start = Extract<SignalType, 9, 3>(p1);
01008   SignalType cycle_stop = Extract<SignalType, 12, 3>(p1);
01009   uint num_dir_cycle = GB(p1, 15, 2);
01010 
01011   if (sigtype > SIGTYPE_LAST) return CMD_ERROR;
01012   if (cycle_start > cycle_stop || cycle_stop > SIGTYPE_LAST) return CMD_ERROR;
01013 
01014   /* You can only build signals on plain rail tiles, and the selected track must exist */
01015   if (!ValParamTrackOrientation(track) || !IsPlainRailTile(tile) ||
01016       !HasTrack(tile, track)) {
01017     return_cmd_error(STR_ERROR_THERE_IS_NO_RAILROAD_TRACK);
01018   }
01019   /* Protect against invalid signal copying */
01020   if (p2 != 0 && (p2 & SignalOnTrack(track)) == 0) return CMD_ERROR;
01021 
01022   CommandCost ret = CheckTileOwnership(tile);
01023   if (ret.Failed()) return ret;
01024 
01025   /* See if this is a valid track combination for signals (no overlap) */
01026   if (TracksOverlap(GetTrackBits(tile))) return_cmd_error(STR_ERROR_NO_SUITABLE_RAILROAD_TRACK);
01027 
01028   /* In case we don't want to change an existing signal, return without error. */
01029   if (HasBit(p1, 17) && HasSignalOnTrack(tile, track)) return CommandCost();
01030 
01031   /* you can not convert a signal if no signal is on track */
01032   if (convert_signal && !HasSignalOnTrack(tile, track)) return_cmd_error(STR_ERROR_THERE_ARE_NO_SIGNALS);
01033 
01034   CommandCost cost;
01035   if (!HasSignalOnTrack(tile, track)) {
01036     /* build new signals */
01037     cost = CommandCost(EXPENSES_CONSTRUCTION, _price[PR_BUILD_SIGNALS]);
01038   } else {
01039     if (p2 != 0 && sigvar != GetSignalVariant(tile, track)) {
01040       /* convert signals <-> semaphores */
01041       cost = CommandCost(EXPENSES_CONSTRUCTION, _price[PR_BUILD_SIGNALS] + _price[PR_CLEAR_SIGNALS]);
01042 
01043     } else if (convert_signal) {
01044       /* convert button pressed */
01045       if (ctrl_pressed || GetSignalVariant(tile, track) != sigvar) {
01046         /* convert electric <-> semaphore */
01047         cost = CommandCost(EXPENSES_CONSTRUCTION, _price[PR_BUILD_SIGNALS] + _price[PR_CLEAR_SIGNALS]);
01048       } else {
01049         /* it is free to change signal type: normal-pre-exit-combo */
01050         cost = CommandCost();
01051       }
01052 
01053     } else {
01054       /* it is free to change orientation/pre-exit-combo signals */
01055       cost = CommandCost();
01056     }
01057   }
01058 
01059   if (flags & DC_EXEC) {
01060     Train *v = NULL;
01061     /* The new/changed signal could block our path. As this can lead to
01062      * stale reservations, we clear the path reservation here and try
01063      * to redo it later on. */
01064     if (HasReservedTracks(tile, TrackToTrackBits(track))) {
01065       v = GetTrainForReservation(tile, track);
01066       if (v != NULL) FreeTrainTrackReservation(v);
01067     }
01068 
01069     if (!HasSignals(tile)) {
01070       /* there are no signals at all on this tile yet */
01071       SetHasSignals(tile, true);
01072       SetSignalStates(tile, 0xF); // all signals are on
01073       SetPresentSignals(tile, 0); // no signals built by default
01074       SetSignalType(tile, track, sigtype);
01075       SetSignalVariant(tile, track, sigvar);
01076     }
01077 
01078     /* Subtract old signal infrastructure count. */
01079     Company::Get(GetTileOwner(tile))->infrastructure.signal -= CountBits(GetPresentSignals(tile));
01080 
01081     if (p2 == 0) {
01082       if (!HasSignalOnTrack(tile, track)) {
01083         /* build new signals */
01084         SetPresentSignals(tile, GetPresentSignals(tile) | (IsPbsSignal(sigtype) ? KillFirstBit(SignalOnTrack(track)) : SignalOnTrack(track)));
01085         SetSignalType(tile, track, sigtype);
01086         SetSignalVariant(tile, track, sigvar);
01087         while (num_dir_cycle-- > 0) CycleSignalSide(tile, track);
01088       } else {
01089         if (convert_signal) {
01090           /* convert signal button pressed */
01091           if (ctrl_pressed) {
01092             /* toggle the present signal variant: SIG_ELECTRIC <-> SIG_SEMAPHORE */
01093             SetSignalVariant(tile, track, (GetSignalVariant(tile, track) == SIG_ELECTRIC) ? SIG_SEMAPHORE : SIG_ELECTRIC);
01094             /* Query current signal type so the check for PBS signals below works. */
01095             sigtype = GetSignalType(tile, track);
01096           } else {
01097             /* convert the present signal to the chosen type and variant */
01098             SetSignalType(tile, track, sigtype);
01099             SetSignalVariant(tile, track, sigvar);
01100             if (IsPbsSignal(sigtype) && (GetPresentSignals(tile) & SignalOnTrack(track)) == SignalOnTrack(track)) {
01101               SetPresentSignals(tile, (GetPresentSignals(tile) & ~SignalOnTrack(track)) | KillFirstBit(SignalOnTrack(track)));
01102             }
01103           }
01104 
01105         } else if (ctrl_pressed) {
01106           /* cycle between cycle_start and cycle_end */
01107           sigtype = (SignalType)(GetSignalType(tile, track) + 1);
01108 
01109           if (sigtype < cycle_start || sigtype > cycle_stop) sigtype = cycle_start;
01110 
01111           SetSignalType(tile, track, sigtype);
01112           if (IsPbsSignal(sigtype) && (GetPresentSignals(tile) & SignalOnTrack(track)) == SignalOnTrack(track)) {
01113             SetPresentSignals(tile, (GetPresentSignals(tile) & ~SignalOnTrack(track)) | KillFirstBit(SignalOnTrack(track)));
01114           }
01115         } else {
01116           /* cycle the signal side: both -> left -> right -> both -> ... */
01117           CycleSignalSide(tile, track);
01118           /* Query current signal type so the check for PBS signals below works. */
01119           sigtype = GetSignalType(tile, track);
01120         }
01121       }
01122     } else {
01123       /* If CmdBuildManySignals is called with copying signals, just copy the
01124        * direction of the first signal given as parameter by CmdBuildManySignals */
01125       SetPresentSignals(tile, (GetPresentSignals(tile) & ~SignalOnTrack(track)) | (p2 & SignalOnTrack(track)));
01126       SetSignalVariant(tile, track, sigvar);
01127       SetSignalType(tile, track, sigtype);
01128     }
01129 
01130     /* Add new signal infrastructure count. */
01131     Company::Get(GetTileOwner(tile))->infrastructure.signal += CountBits(GetPresentSignals(tile));
01132     DirtyCompanyInfrastructureWindows(GetTileOwner(tile));
01133 
01134     if (IsPbsSignal(sigtype)) {
01135       /* PBS signals should show red unless they are on reserved tiles without a train. */
01136       uint mask = GetPresentSignals(tile) & SignalOnTrack(track);
01137       SetSignalStates(tile, (GetSignalStates(tile) & ~mask) | ((HasBit(GetRailReservationTrackBits(tile), track) && EnsureNoVehicleOnGround(tile).Succeeded() ? UINT_MAX : 0) & mask));
01138     }
01139     MarkTileDirtyByTile(tile);
01140     AddTrackToSignalBuffer(tile, track, _current_company);
01141     YapfNotifyTrackLayoutChange(tile, track);
01142     if (v != NULL) {
01143       /* Extend the train's path if it's not stopped or loading, or not at a safe position. */
01144       if (!(((v->vehstatus & VS_STOPPED) && v->cur_speed == 0) || v->current_order.IsType(OT_LOADING)) ||
01145           !IsSafeWaitingPosition(v, v->tile, v->GetVehicleTrackdir(), true, _settings_game.pf.forbid_90_deg)) {
01146         TryPathReserve(v, true);
01147       }
01148     }
01149   }
01150 
01151   return cost;
01152 }
01153 
01154 static bool CheckSignalAutoFill(TileIndex &tile, Trackdir &trackdir, int &signal_ctr, bool remove)
01155 {
01156   tile = AddTileIndexDiffCWrap(tile, _trackdelta[trackdir]);
01157   if (tile == INVALID_TILE) return false;
01158 
01159   /* Check for track bits on the new tile */
01160   TrackdirBits trackdirbits = TrackStatusToTrackdirBits(GetTileTrackStatus(tile, TRANSPORT_RAIL, 0));
01161 
01162   if (TracksOverlap(TrackdirBitsToTrackBits(trackdirbits))) return false;
01163   trackdirbits &= TrackdirReachesTrackdirs(trackdir);
01164 
01165   /* No track bits, must stop */
01166   if (trackdirbits == TRACKDIR_BIT_NONE) return false;
01167 
01168   /* Get the first track dir */
01169   trackdir = RemoveFirstTrackdir(&trackdirbits);
01170 
01171   /* Any left? It's a junction so we stop */
01172   if (trackdirbits != TRACKDIR_BIT_NONE) return false;
01173 
01174   switch (GetTileType(tile)) {
01175     case MP_RAILWAY:
01176       if (IsRailDepot(tile)) return false;
01177       if (!remove && HasSignalOnTrack(tile, TrackdirToTrack(trackdir))) return false;
01178       signal_ctr++;
01179       if (IsDiagonalTrackdir(trackdir)) {
01180         signal_ctr++;
01181         /* Ensure signal_ctr even so X and Y pieces get signals */
01182         ClrBit(signal_ctr, 0);
01183       }
01184       return true;
01185 
01186     case MP_ROAD:
01187       if (!IsLevelCrossing(tile)) return false;
01188       signal_ctr += 2;
01189       return true;
01190 
01191     case MP_TUNNELBRIDGE: {
01192       TileIndex orig_tile = tile; // backup old value
01193 
01194       if (GetTunnelBridgeTransportType(tile) != TRANSPORT_RAIL) return false;
01195       if (GetTunnelBridgeDirection(tile) != TrackdirToExitdir(trackdir)) return false;
01196 
01197       /* Skip to end of tunnel or bridge
01198        * note that tile is a parameter by reference, so it must be updated */
01199       tile = GetOtherTunnelBridgeEnd(tile);
01200 
01201       signal_ctr += (GetTunnelBridgeLength(orig_tile, tile) + 2) * 2;
01202       return true;
01203     }
01204 
01205     default: return false;
01206   }
01207 }
01208 
01226 static CommandCost CmdSignalTrackHelper(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
01227 {
01228   CommandCost total_cost(EXPENSES_CONSTRUCTION);
01229   TileIndex start_tile = tile;
01230 
01231   Track track = Extract<Track, 0, 3>(p2);
01232   bool mode = HasBit(p2, 3);
01233   bool semaphores = HasBit(p2, 4);
01234   bool remove = HasBit(p2, 5);
01235   bool autofill = HasBit(p2, 6);
01236   bool minimise_gaps = HasBit(p2, 10);
01237   byte signal_density = GB(p2, 24, 8);
01238 
01239   if (p1 >= MapSize() || !ValParamTrackOrientation(track)) return CMD_ERROR;
01240   TileIndex end_tile = p1;
01241   if (signal_density == 0 || signal_density > 20) return CMD_ERROR;
01242 
01243   if (!IsPlainRailTile(tile)) return_cmd_error(STR_ERROR_THERE_IS_NO_RAILROAD_TRACK);
01244 
01245   /* for vertical/horizontal tracks, double the given signals density
01246    * since the original amount will be too dense (shorter tracks) */
01247   signal_density *= 2;
01248 
01249   Trackdir trackdir = TrackToTrackdir(track);
01250   CommandCost ret = ValidateAutoDrag(&trackdir, tile, end_tile);
01251   if (ret.Failed()) return ret;
01252 
01253   track = TrackdirToTrack(trackdir); // trackdir might have changed, keep track in sync
01254   Trackdir start_trackdir = trackdir;
01255 
01256   /* Must start on a valid track to be able to avoid loops */
01257   if (!HasTrack(tile, track)) return CMD_ERROR;
01258 
01259   SignalType sigtype = (SignalType)GB(p2, 7, 3);
01260   if (sigtype > SIGTYPE_LAST) return CMD_ERROR;
01261 
01262   byte signals;
01263   /* copy the signal-style of the first rail-piece if existing */
01264   if (HasSignalOnTrack(tile, track)) {
01265     signals = GetPresentSignals(tile) & SignalOnTrack(track);
01266     assert(signals != 0);
01267 
01268     /* copy signal/semaphores style (independent of CTRL) */
01269     semaphores = GetSignalVariant(tile, track) != SIG_ELECTRIC;
01270 
01271     sigtype = GetSignalType(tile, track);
01272     /* Don't but copy entry or exit-signal type */
01273     if (sigtype == SIGTYPE_ENTRY || sigtype == SIGTYPE_EXIT) sigtype = SIGTYPE_NORMAL;
01274   } else { // no signals exist, drag a two-way signal stretch
01275     signals = IsPbsSignal(sigtype) ? SignalAlongTrackdir(trackdir) : SignalOnTrack(track);
01276   }
01277 
01278   byte signal_dir = 0;
01279   if (signals & SignalAlongTrackdir(trackdir))   SetBit(signal_dir, 0);
01280   if (signals & SignalAgainstTrackdir(trackdir)) SetBit(signal_dir, 1);
01281 
01282   /* signal_ctr         - amount of tiles already processed
01283    * last_used_ctr      - amount of tiles before previously placed signal
01284    * signals_density    - setting to put signal on every Nth tile (double space on |, -- tracks)
01285    * last_suitable_ctr  - amount of tiles before last possible signal place
01286    * last_suitable_tile - last tile where it is possible to place a signal
01287    * last_suitable_trackdir - trackdir of the last tile
01288    **********
01289    * trackdir   - trackdir to build with autorail
01290    * semaphores - semaphores or signals
01291    * signals    - is there a signal/semaphore on the first tile, copy its style (two-way/single-way)
01292    *              and convert all others to semaphore/signal
01293    * remove     - 1 remove signals, 0 build signals */
01294   int signal_ctr = 0;
01295   int last_used_ctr = INT_MIN; // initially INT_MIN to force building/removing at the first tile
01296   int last_suitable_ctr = 0;
01297   TileIndex last_suitable_tile = INVALID_TILE;
01298   Trackdir last_suitable_trackdir = INVALID_TRACKDIR;
01299   CommandCost last_error = CMD_ERROR;
01300   bool had_success = false;
01301   for (;;) {
01302     /* only build/remove signals with the specified density */
01303     if (remove || minimise_gaps || signal_ctr % signal_density == 0) {
01304       uint32 p1 = GB(TrackdirToTrack(trackdir), 0, 3);
01305       SB(p1, 3, 1, mode);
01306       SB(p1, 4, 1, semaphores);
01307       SB(p1, 5, 3, sigtype);
01308       if (!remove && signal_ctr == 0) SetBit(p1, 17);
01309 
01310       /* Pick the correct orientation for the track direction */
01311       signals = 0;
01312       if (HasBit(signal_dir, 0)) signals |= SignalAlongTrackdir(trackdir);
01313       if (HasBit(signal_dir, 1)) signals |= SignalAgainstTrackdir(trackdir);
01314 
01315       /* Test tiles in between for suitability as well if minimising gaps. */
01316       bool test_only = !remove && minimise_gaps && signal_ctr < (last_used_ctr + signal_density);
01317       CommandCost ret = DoCommand(tile, p1, signals, test_only ? flags & ~DC_EXEC : flags, remove ? CMD_REMOVE_SIGNALS : CMD_BUILD_SIGNALS);
01318 
01319       if (ret.Succeeded()) {
01320         /* Remember last track piece where we can place a signal. */
01321         last_suitable_ctr = signal_ctr;
01322         last_suitable_tile = tile;
01323         last_suitable_trackdir = trackdir;
01324       } else if (!test_only && last_suitable_tile != INVALID_TILE) {
01325         /* If a signal can't be placed, place it at the last possible position. */
01326         SB(p1, 0, 3, TrackdirToTrack(last_suitable_trackdir));
01327         ClrBit(p1, 17);
01328 
01329         /* Pick the correct orientation for the track direction. */
01330         signals = 0;
01331         if (HasBit(signal_dir, 0)) signals |= SignalAlongTrackdir(last_suitable_trackdir);
01332         if (HasBit(signal_dir, 1)) signals |= SignalAgainstTrackdir(last_suitable_trackdir);
01333 
01334         ret = DoCommand(last_suitable_tile, p1, signals, flags, remove ? CMD_REMOVE_SIGNALS : CMD_BUILD_SIGNALS);
01335       }
01336 
01337       /* Collect cost. */
01338       if (!test_only) {
01339         /* Be user-friendly and try placing signals as much as possible */
01340         if (ret.Succeeded()) {
01341           had_success = true;
01342           total_cost.AddCost(ret);
01343           last_used_ctr = last_suitable_ctr;
01344           last_suitable_tile = INVALID_TILE;
01345         } else {
01346           /* The "No railway" error is the least important one. */
01347           if (ret.GetErrorMessage() != STR_ERROR_THERE_IS_NO_RAILROAD_TRACK ||
01348               last_error.GetErrorMessage() == INVALID_STRING_ID) {
01349             last_error = ret;
01350           }
01351         }
01352       }
01353     }
01354 
01355     if (autofill) {
01356       if (!CheckSignalAutoFill(tile, trackdir, signal_ctr, remove)) break;
01357 
01358       /* Prevent possible loops */
01359       if (tile == start_tile && trackdir == start_trackdir) break;
01360     } else {
01361       if (tile == end_tile) break;
01362 
01363       tile += ToTileIndexDiff(_trackdelta[trackdir]);
01364       signal_ctr++;
01365 
01366       /* toggle railbit for the non-diagonal tracks (|, -- tracks) */
01367       if (IsDiagonalTrackdir(trackdir)) {
01368         signal_ctr++;
01369       } else {
01370         ToggleBit(trackdir, 0);
01371       }
01372     }
01373   }
01374 
01375   return had_success ? total_cost : last_error;
01376 }
01377 
01396 CommandCost CmdBuildSignalTrack(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
01397 {
01398   return CmdSignalTrackHelper(tile, flags, p1, p2, text);
01399 }
01400 
01413 CommandCost CmdRemoveSingleSignal(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
01414 {
01415   Track track = Extract<Track, 0, 3>(p1);
01416 
01417   if (!ValParamTrackOrientation(track) || !IsPlainRailTile(tile) || !HasTrack(tile, track)) {
01418     return_cmd_error(STR_ERROR_THERE_IS_NO_RAILROAD_TRACK);
01419   }
01420   if (!HasSignalOnTrack(tile, track)) {
01421     return_cmd_error(STR_ERROR_THERE_ARE_NO_SIGNALS);
01422   }
01423 
01424   /* Only water can remove signals from anyone */
01425   if (_current_company != OWNER_WATER) {
01426     CommandCost ret = CheckTileOwnership(tile);
01427     if (ret.Failed()) return ret;
01428   }
01429 
01430   /* Do it? */
01431   if (flags & DC_EXEC) {
01432     Train *v = NULL;
01433     if (HasReservedTracks(tile, TrackToTrackBits(track))) {
01434       v = GetTrainForReservation(tile, track);
01435     } else if (IsPbsSignal(GetSignalType(tile, track))) {
01436       /* PBS signal, might be the end of a path reservation. */
01437       Trackdir td = TrackToTrackdir(track);
01438       for (int i = 0; v == NULL && i < 2; i++, td = ReverseTrackdir(td)) {
01439         /* Only test the active signal side. */
01440         if (!HasSignalOnTrackdir(tile, ReverseTrackdir(td))) continue;
01441         TileIndex next = TileAddByDiagDir(tile, TrackdirToExitdir(td));
01442         TrackBits tracks = TrackdirBitsToTrackBits(TrackdirReachesTrackdirs(td));
01443         if (HasReservedTracks(next, tracks)) {
01444           v = GetTrainForReservation(next, TrackBitsToTrack(GetReservedTrackbits(next) & tracks));
01445         }
01446       }
01447     }
01448     Company::Get(GetTileOwner(tile))->infrastructure.signal -= CountBits(GetPresentSignals(tile));
01449     SetPresentSignals(tile, GetPresentSignals(tile) & ~SignalOnTrack(track));
01450     Company::Get(GetTileOwner(tile))->infrastructure.signal += CountBits(GetPresentSignals(tile));
01451     DirtyCompanyInfrastructureWindows(GetTileOwner(tile));
01452 
01453     /* removed last signal from tile? */
01454     if (GetPresentSignals(tile) == 0) {
01455       SetSignalStates(tile, 0);
01456       SetHasSignals(tile, false);
01457       SetSignalVariant(tile, INVALID_TRACK, SIG_ELECTRIC); // remove any possible semaphores
01458     }
01459 
01460     AddTrackToSignalBuffer(tile, track, GetTileOwner(tile));
01461     YapfNotifyTrackLayoutChange(tile, track);
01462     if (v != NULL) TryPathReserve(v, false);
01463 
01464     MarkTileDirtyByTile(tile);
01465   }
01466 
01467   return CommandCost(EXPENSES_CONSTRUCTION, _price[PR_CLEAR_SIGNALS]);
01468 }
01469 
01488 CommandCost CmdRemoveSignalTrack(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
01489 {
01490   return CmdSignalTrackHelper(tile, flags, p1, SetBit(p2, 5), text); // bit 5 is remove bit
01491 }
01492 
01494 static Vehicle *UpdateTrainPowerProc(Vehicle *v, void *data)
01495 {
01496   if (v->type != VEH_TRAIN) return NULL;
01497 
01498   TrainList *affected_trains = static_cast<TrainList*>(data);
01499   affected_trains->Include(Train::From(v)->First());
01500 
01501   return NULL;
01502 }
01503 
01516 CommandCost CmdConvertRail(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
01517 {
01518   RailType totype = Extract<RailType, 0, 4>(p2);
01519 
01520   if (!ValParamRailtype(totype)) return CMD_ERROR;
01521   if (p1 >= MapSize()) return CMD_ERROR;
01522 
01523   TrainList affected_trains;
01524 
01525   CommandCost cost(EXPENSES_CONSTRUCTION);
01526   CommandCost error = CommandCost(STR_ERROR_NO_SUITABLE_RAILROAD_TRACK); // by default, there is no track to convert.
01527   TileArea ta(tile, p1);
01528   TileIterator *iter = HasBit(p2, 4) ? (TileIterator *)new DiagonalTileIterator(tile, p1) : new OrthogonalTileIterator(ta);
01529   for (; (tile = *iter) != INVALID_TILE; ++(*iter)) {
01530     TileType tt = GetTileType(tile);
01531 
01532     /* Check if there is any track on tile */
01533     switch (tt) {
01534       case MP_RAILWAY:
01535         break;
01536       case MP_STATION:
01537         if (!HasStationRail(tile)) continue;
01538         break;
01539       case MP_ROAD:
01540         if (!IsLevelCrossing(tile)) continue;
01541         if (RailNoLevelCrossings(totype)) {
01542           error.MakeError(STR_ERROR_CROSSING_DISALLOWED);
01543           continue;
01544         }
01545         break;
01546       case MP_TUNNELBRIDGE:
01547         if (GetTunnelBridgeTransportType(tile) != TRANSPORT_RAIL) continue;
01548         break;
01549       default: continue;
01550     }
01551 
01552     /* Original railtype we are converting from */
01553     RailType type = GetRailType(tile);
01554 
01555     /* Converting to the same type or converting 'hidden' elrail -> rail */
01556     if (type == totype || (_settings_game.vehicle.disable_elrails && totype == RAILTYPE_RAIL && type == RAILTYPE_ELECTRIC)) continue;
01557 
01558     /* Trying to convert other's rail */
01559     CommandCost ret = CheckTileOwnership(tile);
01560     if (ret.Failed()) {
01561       error = ret;
01562       continue;
01563     }
01564 
01565     SmallVector<Train *, 2> vehicles_affected;
01566 
01567     /* Vehicle on the tile when not converting Rail <-> ElRail
01568      * Tunnels and bridges have special check later */
01569     if (tt != MP_TUNNELBRIDGE) {
01570       if (!IsCompatibleRail(type, totype)) {
01571         CommandCost ret = EnsureNoVehicleOnGround(tile);
01572         if (ret.Failed()) {
01573           error = ret;
01574           continue;
01575         }
01576       }
01577       if (flags & DC_EXEC) { // we can safely convert, too
01578         TrackBits reserved = GetReservedTrackbits(tile);
01579         Track     track;
01580         while ((track = RemoveFirstTrack(&reserved)) != INVALID_TRACK) {
01581           Train *v = GetTrainForReservation(tile, track);
01582           if (v != NULL && !HasPowerOnRail(v->railtype, totype)) {
01583             /* No power on new rail type, reroute. */
01584             FreeTrainTrackReservation(v);
01585             *vehicles_affected.Append() = v;
01586           }
01587         }
01588 
01589         /* Update the company infrastructure counters. */
01590         if (!IsRailStationTile(tile) || !IsStationTileBlocked(tile)) {
01591           Company *c = Company::Get(GetTileOwner(tile));
01592           uint num_pieces = IsLevelCrossingTile(tile) ? LEVELCROSSING_TRACKBIT_FACTOR : 1;
01593           if (IsPlainRailTile(tile)) {
01594             TrackBits bits = GetTrackBits(tile);
01595             num_pieces = CountBits(bits);
01596             if (TracksOverlap(bits)) num_pieces *= num_pieces;
01597           }
01598           c->infrastructure.rail[type] -= num_pieces;
01599           c->infrastructure.rail[totype] += num_pieces;
01600           DirtyCompanyInfrastructureWindows(c->index);
01601         }
01602 
01603         SetRailType(tile, totype);
01604         MarkTileDirtyByTile(tile);
01605         /* update power of train on this tile */
01606         FindVehicleOnPos(tile, &affected_trains, &UpdateTrainPowerProc);
01607       }
01608     }
01609 
01610     switch (tt) {
01611       case MP_RAILWAY:
01612         switch (GetRailTileType(tile)) {
01613           case RAIL_TILE_DEPOT:
01614             if (flags & DC_EXEC) {
01615               /* notify YAPF about the track layout change */
01616               YapfNotifyTrackLayoutChange(tile, GetRailDepotTrack(tile));
01617 
01618               /* Update build vehicle window related to this depot */
01619               InvalidateWindowData(WC_VEHICLE_DEPOT, tile);
01620               InvalidateWindowData(WC_BUILD_VEHICLE, tile);
01621             }
01622             cost.AddCost(RailConvertCost(type, totype));
01623             break;
01624 
01625           default: // RAIL_TILE_NORMAL, RAIL_TILE_SIGNALS
01626             if (flags & DC_EXEC) {
01627               /* notify YAPF about the track layout change */
01628               TrackBits tracks = GetTrackBits(tile);
01629               while (tracks != TRACK_BIT_NONE) {
01630                 YapfNotifyTrackLayoutChange(tile, RemoveFirstTrack(&tracks));
01631               }
01632             }
01633             cost.AddCost(RailConvertCost(type, totype) * CountBits(GetTrackBits(tile)));
01634             break;
01635         }
01636         break;
01637 
01638       case MP_TUNNELBRIDGE: {
01639         TileIndex endtile = GetOtherTunnelBridgeEnd(tile);
01640 
01641         /* If both ends of tunnel/bridge are in the range, do not try to convert twice -
01642          * it would cause assert because of different test and exec runs */
01643         if (endtile < tile && TileX(endtile) >= TileX(ta.tile) && TileX(endtile) < TileX(ta.tile) + ta.w &&
01644             TileY(endtile) >= TileY(ta.tile) && TileY(endtile) < TileY(ta.tile) + ta.h) continue;
01645 
01646         /* When not converting rail <-> el. rail, any vehicle cannot be in tunnel/bridge */
01647         if (!IsCompatibleRail(GetRailType(tile), totype)) {
01648           CommandCost ret = TunnelBridgeIsFree(tile, endtile);
01649           if (ret.Failed()) {
01650             error = ret;
01651             continue;
01652           }
01653         }
01654 
01655         if (flags & DC_EXEC) {
01656           Track track = DiagDirToDiagTrack(GetTunnelBridgeDirection(tile));
01657           if (HasTunnelBridgeReservation(tile)) {
01658             Train *v = GetTrainForReservation(tile, track);
01659             if (v != NULL && !HasPowerOnRail(v->railtype, totype)) {
01660               /* No power on new rail type, reroute. */
01661               FreeTrainTrackReservation(v);
01662               *vehicles_affected.Append() = v;
01663             }
01664           }
01665 
01666           /* Update the company infrastructure counters. */
01667           uint num_pieces = (GetTunnelBridgeLength(tile, endtile) + 2) * TUNNELBRIDGE_TRACKBIT_FACTOR;
01668           Company *c = Company::Get(GetTileOwner(tile));
01669           c->infrastructure.rail[GetRailType(tile)] -= num_pieces;
01670           c->infrastructure.rail[totype] += num_pieces;
01671           DirtyCompanyInfrastructureWindows(c->index);
01672 
01673           SetRailType(tile, totype);
01674           SetRailType(endtile, totype);
01675 
01676           FindVehicleOnPos(tile, &affected_trains, &UpdateTrainPowerProc);
01677           FindVehicleOnPos(endtile, &affected_trains, &UpdateTrainPowerProc);
01678 
01679           YapfNotifyTrackLayoutChange(tile, track);
01680           YapfNotifyTrackLayoutChange(endtile, track);
01681 
01682           MarkTileDirtyByTile(tile);
01683           MarkTileDirtyByTile(endtile);
01684 
01685           if (IsBridge(tile)) {
01686             TileIndexDiff delta = TileOffsByDiagDir(GetTunnelBridgeDirection(tile));
01687             TileIndex t = tile + delta;
01688             for (; t != endtile; t += delta) MarkTileDirtyByTile(t); // TODO encapsulate this into a function
01689           }
01690         }
01691 
01692         cost.AddCost((GetTunnelBridgeLength(tile, endtile) + 2) * RailConvertCost(type, totype));
01693         break;
01694       }
01695 
01696       default: // MP_STATION, MP_ROAD
01697         if (flags & DC_EXEC) {
01698           Track track = ((tt == MP_STATION) ? GetRailStationTrack(tile) : GetCrossingRailTrack(tile));
01699           YapfNotifyTrackLayoutChange(tile, track);
01700         }
01701 
01702         cost.AddCost(RailConvertCost(type, totype));
01703         break;
01704     }
01705 
01706     for (uint i = 0; i < vehicles_affected.Length(); ++i) {
01707       TryPathReserve(vehicles_affected[i], true);
01708     }
01709   }
01710 
01711   if (flags & DC_EXEC) {
01712     /* Railtype changed, update trains as when entering different track */
01713     for (Train **v = affected_trains.Begin(); v != affected_trains.End(); v++) {
01714       (*v)->ConsistChanged(true);
01715     }
01716   }
01717 
01718   delete iter;
01719   return (cost.GetCost() == 0) ? error : cost;
01720 }
01721 
01722 static CommandCost RemoveTrainDepot(TileIndex tile, DoCommandFlag flags)
01723 {
01724   if (_current_company != OWNER_WATER) {
01725     CommandCost ret = CheckTileOwnership(tile);
01726     if (ret.Failed()) return ret;
01727   }
01728 
01729   CommandCost ret = EnsureNoVehicleOnGround(tile);
01730   if (ret.Failed()) return ret;
01731 
01732   if (flags & DC_EXEC) {
01733     /* read variables before the depot is removed */
01734     DiagDirection dir = GetRailDepotDirection(tile);
01735     Owner owner = GetTileOwner(tile);
01736     Train *v = NULL;
01737 
01738     if (HasDepotReservation(tile)) {
01739       v = GetTrainForReservation(tile, DiagDirToDiagTrack(dir));
01740       if (v != NULL) FreeTrainTrackReservation(v);
01741     }
01742 
01743     Company::Get(owner)->infrastructure.rail[GetRailType(tile)]--;
01744     DirtyCompanyInfrastructureWindows(owner);
01745 
01746     delete Depot::GetByTile(tile);
01747     DoClearSquare(tile);
01748     AddSideToSignalBuffer(tile, dir, owner);
01749     YapfNotifyTrackLayoutChange(tile, DiagDirToDiagTrack(dir));
01750     if (v != NULL) TryPathReserve(v, true);
01751   }
01752 
01753   return CommandCost(EXPENSES_CONSTRUCTION, _price[PR_CLEAR_DEPOT_TRAIN]);
01754 }
01755 
01756 static CommandCost ClearTile_Track(TileIndex tile, DoCommandFlag flags)
01757 {
01758   CommandCost cost(EXPENSES_CONSTRUCTION);
01759 
01760   if (flags & DC_AUTO) {
01761     if (!IsTileOwner(tile, _current_company)) {
01762       return_cmd_error(STR_ERROR_AREA_IS_OWNED_BY_ANOTHER);
01763     }
01764 
01765     if (IsPlainRail(tile)) {
01766       return_cmd_error(STR_ERROR_MUST_REMOVE_RAILROAD_TRACK);
01767     } else {
01768       return_cmd_error(STR_ERROR_BUILDING_MUST_BE_DEMOLISHED);
01769     }
01770   }
01771 
01772   switch (GetRailTileType(tile)) {
01773     case RAIL_TILE_SIGNALS:
01774     case RAIL_TILE_NORMAL: {
01775       Slope tileh = GetTileSlope(tile);
01776       /* Is there flat water on the lower halftile that gets cleared expensively? */
01777       bool water_ground = (GetRailGroundType(tile) == RAIL_GROUND_WATER && IsSlopeWithOneCornerRaised(tileh));
01778 
01779       TrackBits tracks = GetTrackBits(tile);
01780       while (tracks != TRACK_BIT_NONE) {
01781         Track track = RemoveFirstTrack(&tracks);
01782         CommandCost ret = DoCommand(tile, 0, track, flags, CMD_REMOVE_SINGLE_RAIL);
01783         if (ret.Failed()) return ret;
01784         cost.AddCost(ret);
01785       }
01786 
01787       /* When bankrupting, don't make water dirty, there could be a ship on lower halftile.
01788        * Same holds for non-companies clearing the tile, e.g. disasters. */
01789       if (water_ground && !(flags & DC_BANKRUPT) && Company::IsValidID(_current_company)) {
01790         CommandCost ret = EnsureNoVehicleOnGround(tile);
01791         if (ret.Failed()) return ret;
01792 
01793         /* The track was removed, and left a coast tile. Now also clear the water. */
01794         if (flags & DC_EXEC) DoClearSquare(tile);
01795         cost.AddCost(_price[PR_CLEAR_WATER]);
01796       }
01797 
01798       return cost;
01799     }
01800 
01801     case RAIL_TILE_DEPOT:
01802       return RemoveTrainDepot(tile, flags);
01803 
01804     default:
01805       return CMD_ERROR;
01806   }
01807 }
01808 
01813 static uint GetSaveSlopeZ(uint x, uint y, Track track)
01814 {
01815   switch (track) {
01816     case TRACK_UPPER: x &= ~0xF; y &= ~0xF; break;
01817     case TRACK_LOWER: x |=  0xF; y |=  0xF; break;
01818     case TRACK_LEFT:  x |=  0xF; y &= ~0xF; break;
01819     case TRACK_RIGHT: x &= ~0xF; y |=  0xF; break;
01820     default: break;
01821   }
01822   return GetSlopePixelZ(x, y);
01823 }
01824 
01825 static void DrawSingleSignal(TileIndex tile, const RailtypeInfo *rti, Track track, SignalState condition, SignalOffsets image, uint pos)
01826 {
01827   bool side;
01828   switch (_settings_game.construction.train_signal_side) {
01829     case 0:  side = false;                                 break; // left
01830     case 2:  side = true;                                  break; // right
01831     default: side = _settings_game.vehicle.road_side != 0; break; // driving side
01832   }
01833   static const Point SignalPositions[2][12] = {
01834     { // Signals on the left side
01835     /*  LEFT      LEFT      RIGHT     RIGHT     UPPER     UPPER */
01836       { 8,  5}, {14,  1}, { 1, 14}, { 9, 11}, { 1,  0}, { 3, 10},
01837     /*  LOWER     LOWER     X         X         Y         Y     */
01838       {11,  4}, {14, 14}, {11,  3}, { 4, 13}, { 3,  4}, {11, 13}
01839     }, { // Signals on the right side
01840     /*  LEFT      LEFT      RIGHT     RIGHT     UPPER     UPPER */
01841       {14,  1}, {12, 10}, { 4,  6}, { 1, 14}, {10,  4}, { 0,  1},
01842     /*  LOWER     LOWER     X         X         Y         Y     */
01843       {14, 14}, { 5, 12}, {11, 13}, { 4,  3}, {13,  4}, { 3, 11}
01844     }
01845   };
01846 
01847   uint x = TileX(tile) * TILE_SIZE + SignalPositions[side][pos].x;
01848   uint y = TileY(tile) * TILE_SIZE + SignalPositions[side][pos].y;
01849 
01850   SignalType type       = GetSignalType(tile, track);
01851   SignalVariant variant = GetSignalVariant(tile, track);
01852 
01853   SpriteID sprite = GetCustomSignalSprite(rti, tile, type, variant, condition);
01854   if (sprite != 0) {
01855     sprite += image;
01856   } else {
01857     /* Normal electric signals are stored in a different sprite block than all other signals. */
01858     sprite = (type == SIGTYPE_NORMAL && variant == SIG_ELECTRIC) ? SPR_ORIGINAL_SIGNALS_BASE : SPR_SIGNALS_BASE - 16;
01859     sprite += type * 16 + variant * 64 + image * 2 + condition + (type > SIGTYPE_LAST_NOPBS ? 64 : 0);
01860   }
01861 
01862   AddSortableSpriteToDraw(sprite, PAL_NONE, x, y, 1, 1, BB_HEIGHT_UNDER_BRIDGE, GetSaveSlopeZ(x, y, track));
01863 }
01864 
01865 static uint32 _drawtile_track_palette;
01866 
01867 
01868 static void DrawTrackFence_NW(const TileInfo *ti, SpriteID base_image)
01869 {
01870   RailFenceOffset rfo = RFO_FLAT_X;
01871   if (ti->tileh & SLOPE_NW) rfo = (ti->tileh & SLOPE_W) ? RFO_SLOPE_SW : RFO_SLOPE_NE;
01872   AddSortableSpriteToDraw(base_image + rfo, _drawtile_track_palette,
01873     ti->x, ti->y + 1, 16, 1, 4, ti->z);
01874 }
01875 
01876 static void DrawTrackFence_SE(const TileInfo *ti, SpriteID base_image)
01877 {
01878   RailFenceOffset rfo = RFO_FLAT_X;
01879   if (ti->tileh & SLOPE_SE) rfo = (ti->tileh & SLOPE_S) ? RFO_SLOPE_SW : RFO_SLOPE_NE;
01880   AddSortableSpriteToDraw(base_image + rfo, _drawtile_track_palette,
01881     ti->x, ti->y + TILE_SIZE - 1, 16, 1, 4, ti->z);
01882 }
01883 
01884 static void DrawTrackFence_NW_SE(const TileInfo *ti, SpriteID base_image)
01885 {
01886   DrawTrackFence_NW(ti, base_image);
01887   DrawTrackFence_SE(ti, base_image);
01888 }
01889 
01890 static void DrawTrackFence_NE(const TileInfo *ti, SpriteID base_image)
01891 {
01892   RailFenceOffset rfo = RFO_FLAT_Y;
01893   if (ti->tileh & SLOPE_NE) rfo = (ti->tileh & SLOPE_E) ? RFO_SLOPE_SE : RFO_SLOPE_NW;
01894   AddSortableSpriteToDraw(base_image + rfo, _drawtile_track_palette,
01895     ti->x + 1, ti->y, 1, 16, 4, ti->z);
01896 }
01897 
01898 static void DrawTrackFence_SW(const TileInfo *ti, SpriteID base_image)
01899 {
01900   RailFenceOffset rfo = RFO_FLAT_Y;
01901   if (ti->tileh & SLOPE_SW) rfo = (ti->tileh & SLOPE_S) ? RFO_SLOPE_SE : RFO_SLOPE_NW;
01902   AddSortableSpriteToDraw(base_image + rfo, _drawtile_track_palette,
01903     ti->x + TILE_SIZE - 1, ti->y, 1, 16, 4, ti->z);
01904 }
01905 
01906 static void DrawTrackFence_NE_SW(const TileInfo *ti, SpriteID base_image)
01907 {
01908   DrawTrackFence_NE(ti, base_image);
01909   DrawTrackFence_SW(ti, base_image);
01910 }
01911 
01915 static void DrawTrackFence_NS_1(const TileInfo *ti, SpriteID base_image)
01916 {
01917   int z = ti->z + GetSlopePixelZInCorner(RemoveHalftileSlope(ti->tileh), CORNER_W);
01918   AddSortableSpriteToDraw(base_image + RFO_FLAT_VERT, _drawtile_track_palette,
01919     ti->x + TILE_SIZE / 2, ti->y + TILE_SIZE / 2, 1, 1, 4, z);
01920 }
01921 
01925 static void DrawTrackFence_NS_2(const TileInfo *ti, SpriteID base_image)
01926 {
01927   int z = ti->z + GetSlopePixelZInCorner(RemoveHalftileSlope(ti->tileh), CORNER_E);
01928   AddSortableSpriteToDraw(base_image + RFO_FLAT_VERT, _drawtile_track_palette,
01929     ti->x + TILE_SIZE / 2, ti->y + TILE_SIZE / 2, 1, 1, 4, z);
01930 }
01931 
01935 static void DrawTrackFence_WE_1(const TileInfo *ti, SpriteID base_image)
01936 {
01937   int z = ti->z + GetSlopePixelZInCorner(RemoveHalftileSlope(ti->tileh), CORNER_N);
01938   AddSortableSpriteToDraw(base_image + RFO_FLAT_HORZ, _drawtile_track_palette,
01939     ti->x + TILE_SIZE / 2, ti->y + TILE_SIZE / 2, 1, 1, 4, z);
01940 }
01941 
01945 static void DrawTrackFence_WE_2(const TileInfo *ti, SpriteID base_image)
01946 {
01947   int z = ti->z + GetSlopePixelZInCorner(RemoveHalftileSlope(ti->tileh), CORNER_S);
01948   AddSortableSpriteToDraw(base_image + RFO_FLAT_HORZ, _drawtile_track_palette,
01949     ti->x + TILE_SIZE / 2, ti->y + TILE_SIZE / 2, 1, 1, 4, z);
01950 }
01951 
01952 
01953 static void DrawTrackDetails(const TileInfo *ti, const RailtypeInfo *rti)
01954 {
01955   /* Base sprite for track fences.
01956    * Note: Halftile slopes only have fences on the upper part. */
01957   SpriteID base_image = GetCustomRailSprite(rti, ti->tile, RTSG_FENCES, IsHalftileSlope(ti->tileh) ? TCX_UPPER_HALFTILE : TCX_NORMAL);
01958   if (base_image == 0) base_image = SPR_TRACK_FENCE_FLAT_X;
01959 
01960   switch (GetRailGroundType(ti->tile)) {
01961     case RAIL_GROUND_FENCE_NW:     DrawTrackFence_NW(ti, base_image);    break;
01962     case RAIL_GROUND_FENCE_SE:     DrawTrackFence_SE(ti, base_image);    break;
01963     case RAIL_GROUND_FENCE_SENW:   DrawTrackFence_NW_SE(ti, base_image); break;
01964     case RAIL_GROUND_FENCE_NE:     DrawTrackFence_NE(ti, base_image);    break;
01965     case RAIL_GROUND_FENCE_SW:     DrawTrackFence_SW(ti, base_image);    break;
01966     case RAIL_GROUND_FENCE_NESW:   DrawTrackFence_NE_SW(ti, base_image); break;
01967     case RAIL_GROUND_FENCE_VERT1:  DrawTrackFence_NS_1(ti, base_image);  break;
01968     case RAIL_GROUND_FENCE_VERT2:  DrawTrackFence_NS_2(ti, base_image);  break;
01969     case RAIL_GROUND_FENCE_HORIZ1: DrawTrackFence_WE_1(ti, base_image);  break;
01970     case RAIL_GROUND_FENCE_HORIZ2: DrawTrackFence_WE_2(ti, base_image);  break;
01971     case RAIL_GROUND_WATER: {
01972       Corner track_corner;
01973       if (IsHalftileSlope(ti->tileh)) {
01974         /* Steep slope or one-corner-raised slope with halftile foundation */
01975         track_corner = GetHalftileSlopeCorner(ti->tileh);
01976       } else {
01977         /* Three-corner-raised slope */
01978         track_corner = OppositeCorner(GetHighestSlopeCorner(ComplementSlope(ti->tileh)));
01979       }
01980       switch (track_corner) {
01981         case CORNER_W: DrawTrackFence_NS_1(ti, base_image); break;
01982         case CORNER_S: DrawTrackFence_WE_2(ti, base_image); break;
01983         case CORNER_E: DrawTrackFence_NS_2(ti, base_image); break;
01984         case CORNER_N: DrawTrackFence_WE_1(ti, base_image); break;
01985         default: NOT_REACHED();
01986       }
01987       break;
01988     }
01989     default: break;
01990   }
01991 }
01992 
01993 /* SubSprite for drawing the track halftile of 'three-corners-raised'-sloped rail sprites. */
01994 static const int INF = 1000; // big number compared to tilesprite size
01995 static const SubSprite _halftile_sub_sprite[4] = {
01996   { -INF    , -INF  , 32 - 33, INF     }, // CORNER_W, clip 33 pixels from right
01997   { -INF    ,  0 + 7, INF    , INF     }, // CORNER_S, clip 7 pixels from top
01998   { -31 + 33, -INF  , INF    , INF     }, // CORNER_E, clip 33 pixels from left
01999   { -INF    , -INF  , INF    , 30 - 23 }  // CORNER_N, clip 23 pixels from bottom
02000 };
02001 
02002 static inline void DrawTrackSprite(SpriteID sprite, PaletteID pal, const TileInfo *ti, Slope s)
02003 {
02004   DrawGroundSprite(sprite, pal, NULL, 0, (ti->tileh & s) ? -8 : 0);
02005 }
02006 
02007 static void DrawTrackBitsOverlay(TileInfo *ti, TrackBits track, const RailtypeInfo *rti)
02008 {
02009   RailGroundType rgt = GetRailGroundType(ti->tile);
02010   Foundation f = GetRailFoundation(ti->tileh, track);
02011   Corner halftile_corner = CORNER_INVALID;
02012 
02013   if (IsNonContinuousFoundation(f)) {
02014     /* Save halftile corner */
02015     halftile_corner = (f == FOUNDATION_STEEP_BOTH ? GetHighestSlopeCorner(ti->tileh) : GetHalftileFoundationCorner(f));
02016     /* Draw lower part first */
02017     track &= ~CornerToTrackBits(halftile_corner);
02018     f = (f == FOUNDATION_STEEP_BOTH ? FOUNDATION_STEEP_LOWER : FOUNDATION_NONE);
02019   }
02020 
02021   DrawFoundation(ti, f);
02022   /* DrawFoundation modifies ti */
02023 
02024   /* Draw ground */
02025   if (rgt == RAIL_GROUND_WATER) {
02026     if (track != TRACK_BIT_NONE || IsSteepSlope(ti->tileh)) {
02027       /* three-corner-raised slope or steep slope with track on upper part */
02028       DrawShoreTile(ti->tileh);
02029     } else {
02030       /* single-corner-raised slope with track on upper part */
02031       DrawGroundSprite(SPR_FLAT_WATER_TILE, PAL_NONE);
02032     }
02033   } else {
02034     SpriteID image;
02035 
02036     switch (rgt) {
02037       case RAIL_GROUND_BARREN:     image = SPR_FLAT_BARE_LAND;  break;
02038       case RAIL_GROUND_ICE_DESERT: image = SPR_FLAT_SNOW_DESERT_TILE; break;
02039       default:                     image = SPR_FLAT_GRASS_TILE; break;
02040     }
02041 
02042     image += SlopeToSpriteOffset(ti->tileh);
02043 
02044     DrawGroundSprite(image, PAL_NONE);
02045   }
02046 
02047   SpriteID overlay = GetCustomRailSprite(rti, ti->tile, RTSG_OVERLAY);
02048   SpriteID ground = GetCustomRailSprite(rti, ti->tile, RTSG_GROUND);
02049   TrackBits pbs = _settings_client.gui.show_track_reservation ? GetRailReservationTrackBits(ti->tile) : TRACK_BIT_NONE;
02050 
02051   if (track == TRACK_BIT_NONE) {
02052     /* Half-tile foundation, no track here? */
02053   } else if (ti->tileh == SLOPE_NW && track == TRACK_BIT_Y) {
02054     DrawGroundSprite(ground + RTO_SLOPE_NW, PAL_NONE);
02055     if (pbs != TRACK_BIT_NONE) DrawGroundSprite(overlay + 9, PALETTE_CRASH);
02056   } else if (ti->tileh == SLOPE_NE && track == TRACK_BIT_X) {
02057     DrawGroundSprite(ground + RTO_SLOPE_NE, PAL_NONE);
02058     if (pbs != TRACK_BIT_NONE) DrawGroundSprite(overlay + 6, PALETTE_CRASH);
02059   } else if (ti->tileh == SLOPE_SE && track == TRACK_BIT_Y) {
02060     DrawGroundSprite(ground + RTO_SLOPE_SE, PAL_NONE);
02061     if (pbs != TRACK_BIT_NONE) DrawGroundSprite(overlay + 7, PALETTE_CRASH);
02062   } else if (ti->tileh == SLOPE_SW && track == TRACK_BIT_X) {
02063     DrawGroundSprite(ground + RTO_SLOPE_SW, PAL_NONE);
02064     if (pbs != TRACK_BIT_NONE) DrawGroundSprite(overlay + 8, PALETTE_CRASH);
02065   } else {
02066     switch (track) {
02067       /* Draw single ground sprite when not overlapping. No track overlay
02068        * is necessary for these sprites. */
02069       case TRACK_BIT_X:     DrawGroundSprite(ground + RTO_X, PAL_NONE); break;
02070       case TRACK_BIT_Y:     DrawGroundSprite(ground + RTO_Y, PAL_NONE); break;
02071       case TRACK_BIT_UPPER: DrawTrackSprite(ground + RTO_N, PAL_NONE, ti, SLOPE_N); break;
02072       case TRACK_BIT_LOWER: DrawTrackSprite(ground + RTO_S, PAL_NONE, ti, SLOPE_S); break;
02073       case TRACK_BIT_RIGHT: DrawTrackSprite(ground + RTO_E, PAL_NONE, ti, SLOPE_E); break;
02074       case TRACK_BIT_LEFT:  DrawTrackSprite(ground + RTO_W, PAL_NONE, ti, SLOPE_W); break;
02075       case TRACK_BIT_CROSS: DrawGroundSprite(ground + RTO_CROSSING_XY, PAL_NONE); break;
02076       case TRACK_BIT_HORZ:  DrawTrackSprite(ground + RTO_N, PAL_NONE, ti, SLOPE_N);
02077                             DrawTrackSprite(ground + RTO_S, PAL_NONE, ti, SLOPE_S); break;
02078       case TRACK_BIT_VERT:  DrawTrackSprite(ground + RTO_E, PAL_NONE, ti, SLOPE_E);
02079                             DrawTrackSprite(ground + RTO_W, PAL_NONE, ti, SLOPE_W); break;
02080 
02081       default:
02082         /* We're drawing a junction tile */
02083         if ((track & TRACK_BIT_3WAY_NE) == 0) {
02084           DrawGroundSprite(ground + RTO_JUNCTION_SW, PAL_NONE);
02085         } else if ((track & TRACK_BIT_3WAY_SW) == 0) {
02086           DrawGroundSprite(ground + RTO_JUNCTION_NE, PAL_NONE);
02087         } else if ((track & TRACK_BIT_3WAY_NW) == 0) {
02088           DrawGroundSprite(ground + RTO_JUNCTION_SE, PAL_NONE);
02089         } else if ((track & TRACK_BIT_3WAY_SE) == 0) {
02090           DrawGroundSprite(ground + RTO_JUNCTION_NW, PAL_NONE);
02091         } else {
02092           DrawGroundSprite(ground + RTO_JUNCTION_NSEW, PAL_NONE);
02093         }
02094 
02095         /* Mask out PBS bits as we shall draw them afterwards anyway. */
02096         track &= ~pbs;
02097 
02098         /* Draw regular track bits */
02099         if (track & TRACK_BIT_X)     DrawGroundSprite(overlay + RTO_X, PAL_NONE);
02100         if (track & TRACK_BIT_Y)     DrawGroundSprite(overlay + RTO_Y, PAL_NONE);
02101         if (track & TRACK_BIT_UPPER) DrawGroundSprite(overlay + RTO_N, PAL_NONE);
02102         if (track & TRACK_BIT_LOWER) DrawGroundSprite(overlay + RTO_S, PAL_NONE);
02103         if (track & TRACK_BIT_RIGHT) DrawGroundSprite(overlay + RTO_E, PAL_NONE);
02104         if (track & TRACK_BIT_LEFT)  DrawGroundSprite(overlay + RTO_W, PAL_NONE);
02105     }
02106 
02107     /* Draw reserved track bits */
02108     if (pbs & TRACK_BIT_X)     DrawGroundSprite(overlay + RTO_X, PALETTE_CRASH);
02109     if (pbs & TRACK_BIT_Y)     DrawGroundSprite(overlay + RTO_Y, PALETTE_CRASH);
02110     if (pbs & TRACK_BIT_UPPER) DrawTrackSprite(overlay + RTO_N, PALETTE_CRASH, ti, SLOPE_N);
02111     if (pbs & TRACK_BIT_LOWER) DrawTrackSprite(overlay + RTO_S, PALETTE_CRASH, ti, SLOPE_S);
02112     if (pbs & TRACK_BIT_RIGHT) DrawTrackSprite(overlay + RTO_E, PALETTE_CRASH, ti, SLOPE_E);
02113     if (pbs & TRACK_BIT_LEFT)  DrawTrackSprite(overlay + RTO_W, PALETTE_CRASH, ti, SLOPE_W);
02114   }
02115 
02116   if (IsValidCorner(halftile_corner)) {
02117     DrawFoundation(ti, HalftileFoundation(halftile_corner));
02118     overlay = GetCustomRailSprite(rti, ti->tile, RTSG_OVERLAY, TCX_UPPER_HALFTILE);
02119     ground = GetCustomRailSprite(rti, ti->tile, RTSG_GROUND, TCX_UPPER_HALFTILE);
02120 
02121     /* Draw higher halftile-overlay: Use the sloped sprites with three corners raised. They probably best fit the lightning. */
02122     Slope fake_slope = SlopeWithThreeCornersRaised(OppositeCorner(halftile_corner));
02123 
02124     SpriteID image;
02125     switch (rgt) {
02126       case RAIL_GROUND_BARREN:     image = SPR_FLAT_BARE_LAND;  break;
02127       case RAIL_GROUND_ICE_DESERT:
02128       case RAIL_GROUND_HALF_SNOW:  image = SPR_FLAT_SNOW_DESERT_TILE; break;
02129       default:                     image = SPR_FLAT_GRASS_TILE; break;
02130     }
02131 
02132     image += SlopeToSpriteOffset(fake_slope);
02133 
02134     DrawGroundSprite(image, PAL_NONE, &(_halftile_sub_sprite[halftile_corner]));
02135 
02136     track = CornerToTrackBits(halftile_corner);
02137 
02138     int offset;
02139     switch (track) {
02140       default: NOT_REACHED();
02141       case TRACK_BIT_UPPER: offset = RTO_N; break;
02142       case TRACK_BIT_LOWER: offset = RTO_S; break;
02143       case TRACK_BIT_RIGHT: offset = RTO_E; break;
02144       case TRACK_BIT_LEFT:  offset = RTO_W; break;
02145     }
02146 
02147     DrawTrackSprite(ground + offset, PAL_NONE, ti, fake_slope);
02148     if (_settings_client.gui.show_track_reservation && HasReservedTracks(ti->tile, track)) {
02149       DrawTrackSprite(overlay + offset, PALETTE_CRASH, ti, fake_slope);
02150     }
02151   }
02152 }
02153 
02159 static void DrawTrackBits(TileInfo *ti, TrackBits track)
02160 {
02161   const RailtypeInfo *rti = GetRailTypeInfo(GetRailType(ti->tile));
02162 
02163   if (rti->UsesOverlay()) {
02164     DrawTrackBitsOverlay(ti, track, rti);
02165     return;
02166   }
02167 
02168   RailGroundType rgt = GetRailGroundType(ti->tile);
02169   Foundation f = GetRailFoundation(ti->tileh, track);
02170   Corner halftile_corner = CORNER_INVALID;
02171 
02172   if (IsNonContinuousFoundation(f)) {
02173     /* Save halftile corner */
02174     halftile_corner = (f == FOUNDATION_STEEP_BOTH ? GetHighestSlopeCorner(ti->tileh) : GetHalftileFoundationCorner(f));
02175     /* Draw lower part first */
02176     track &= ~CornerToTrackBits(halftile_corner);
02177     f = (f == FOUNDATION_STEEP_BOTH ? FOUNDATION_STEEP_LOWER : FOUNDATION_NONE);
02178   }
02179 
02180   DrawFoundation(ti, f);
02181   /* DrawFoundation modifies ti */
02182 
02183   SpriteID image;
02184   PaletteID pal = PAL_NONE;
02185   const SubSprite *sub = NULL;
02186   bool junction = false;
02187 
02188   /* Select the sprite to use. */
02189   if (track == 0) {
02190     /* Clear ground (only track on halftile foundation) */
02191     if (rgt == RAIL_GROUND_WATER) {
02192       if (IsSteepSlope(ti->tileh)) {
02193         DrawShoreTile(ti->tileh);
02194         image = 0;
02195       } else {
02196         image = SPR_FLAT_WATER_TILE;
02197       }
02198     } else {
02199       switch (rgt) {
02200         case RAIL_GROUND_BARREN:     image = SPR_FLAT_BARE_LAND;  break;
02201         case RAIL_GROUND_ICE_DESERT: image = SPR_FLAT_SNOW_DESERT_TILE; break;
02202         default:                     image = SPR_FLAT_GRASS_TILE; break;
02203       }
02204       image += SlopeToSpriteOffset(ti->tileh);
02205     }
02206   } else {
02207     if (ti->tileh != SLOPE_FLAT) {
02208       /* track on non-flat ground */
02209       image = _track_sloped_sprites[ti->tileh - 1] + rti->base_sprites.track_y;
02210     } else {
02211       /* track on flat ground */
02212       (image = rti->base_sprites.track_y, track == TRACK_BIT_Y) ||
02213       (image++,                           track == TRACK_BIT_X) ||
02214       (image++,                           track == TRACK_BIT_UPPER) ||
02215       (image++,                           track == TRACK_BIT_LOWER) ||
02216       (image++,                           track == TRACK_BIT_RIGHT) ||
02217       (image++,                           track == TRACK_BIT_LEFT) ||
02218       (image++,                           track == TRACK_BIT_CROSS) ||
02219 
02220       (image = rti->base_sprites.track_ns, track == TRACK_BIT_HORZ) ||
02221       (image++,                            track == TRACK_BIT_VERT) ||
02222 
02223       (junction = true, false) ||
02224       (image = rti->base_sprites.ground, (track & TRACK_BIT_3WAY_NE) == 0) ||
02225       (image++,                          (track & TRACK_BIT_3WAY_SW) == 0) ||
02226       (image++,                          (track & TRACK_BIT_3WAY_NW) == 0) ||
02227       (image++,                          (track & TRACK_BIT_3WAY_SE) == 0) ||
02228       (image++, true);
02229     }
02230 
02231     switch (rgt) {
02232       case RAIL_GROUND_BARREN:     pal = PALETTE_TO_BARE_LAND; break;
02233       case RAIL_GROUND_ICE_DESERT: image += rti->snow_offset;  break;
02234       case RAIL_GROUND_WATER: {
02235         /* three-corner-raised slope */
02236         DrawShoreTile(ti->tileh);
02237         Corner track_corner = OppositeCorner(GetHighestSlopeCorner(ComplementSlope(ti->tileh)));
02238         sub = &(_halftile_sub_sprite[track_corner]);
02239         break;
02240       }
02241       default: break;
02242     }
02243   }
02244 
02245   if (image != 0) DrawGroundSprite(image, pal, sub);
02246 
02247   /* Draw track pieces individually for junction tiles */
02248   if (junction) {
02249     if (track & TRACK_BIT_X)     DrawGroundSprite(rti->base_sprites.single_x, PAL_NONE);
02250     if (track & TRACK_BIT_Y)     DrawGroundSprite(rti->base_sprites.single_y, PAL_NONE);
02251     if (track & TRACK_BIT_UPPER) DrawGroundSprite(rti->base_sprites.single_n, PAL_NONE);
02252     if (track & TRACK_BIT_LOWER) DrawGroundSprite(rti->base_sprites.single_s, PAL_NONE);
02253     if (track & TRACK_BIT_LEFT)  DrawGroundSprite(rti->base_sprites.single_w, PAL_NONE);
02254     if (track & TRACK_BIT_RIGHT) DrawGroundSprite(rti->base_sprites.single_e, PAL_NONE);
02255   }
02256 
02257   /* PBS debugging, draw reserved tracks darker */
02258   if (_game_mode != GM_MENU && _settings_client.gui.show_track_reservation) {
02259     /* Get reservation, but mask track on halftile slope */
02260     TrackBits pbs = GetRailReservationTrackBits(ti->tile) & track;
02261     if (pbs & TRACK_BIT_X) {
02262       if (ti->tileh == SLOPE_FLAT || ti->tileh == SLOPE_ELEVATED) {
02263         DrawGroundSprite(rti->base_sprites.single_x, PALETTE_CRASH);
02264       } else {
02265         DrawGroundSprite(_track_sloped_sprites[ti->tileh - 1] + rti->base_sprites.single_sloped - 20, PALETTE_CRASH);
02266       }
02267     }
02268     if (pbs & TRACK_BIT_Y) {
02269       if (ti->tileh == SLOPE_FLAT || ti->tileh == SLOPE_ELEVATED) {
02270         DrawGroundSprite(rti->base_sprites.single_y, PALETTE_CRASH);
02271       } else {
02272         DrawGroundSprite(_track_sloped_sprites[ti->tileh - 1] + rti->base_sprites.single_sloped - 20, PALETTE_CRASH);
02273       }
02274     }
02275     if (pbs & TRACK_BIT_UPPER) DrawGroundSprite(rti->base_sprites.single_n, PALETTE_CRASH, NULL, 0, ti->tileh & SLOPE_N ? -(int)TILE_HEIGHT : 0);
02276     if (pbs & TRACK_BIT_LOWER) DrawGroundSprite(rti->base_sprites.single_s, PALETTE_CRASH, NULL, 0, ti->tileh & SLOPE_S ? -(int)TILE_HEIGHT : 0);
02277     if (pbs & TRACK_BIT_LEFT)  DrawGroundSprite(rti->base_sprites.single_w, PALETTE_CRASH, NULL, 0, ti->tileh & SLOPE_W ? -(int)TILE_HEIGHT : 0);
02278     if (pbs & TRACK_BIT_RIGHT) DrawGroundSprite(rti->base_sprites.single_e, PALETTE_CRASH, NULL, 0, ti->tileh & SLOPE_E ? -(int)TILE_HEIGHT : 0);
02279   }
02280 
02281   if (IsValidCorner(halftile_corner)) {
02282     DrawFoundation(ti, HalftileFoundation(halftile_corner));
02283 
02284     /* Draw higher halftile-overlay: Use the sloped sprites with three corners raised. They probably best fit the lightning. */
02285     Slope fake_slope = SlopeWithThreeCornersRaised(OppositeCorner(halftile_corner));
02286     image = _track_sloped_sprites[fake_slope - 1] + rti->base_sprites.track_y;
02287     pal = PAL_NONE;
02288     switch (rgt) {
02289       case RAIL_GROUND_BARREN:     pal = PALETTE_TO_BARE_LAND; break;
02290       case RAIL_GROUND_ICE_DESERT:
02291       case RAIL_GROUND_HALF_SNOW:  image += rti->snow_offset;  break; // higher part has snow in this case too
02292       default: break;
02293     }
02294     DrawGroundSprite(image, pal, &(_halftile_sub_sprite[halftile_corner]));
02295 
02296     if (_game_mode != GM_MENU && _settings_client.gui.show_track_reservation && HasReservedTracks(ti->tile, CornerToTrackBits(halftile_corner))) {
02297       static const byte _corner_to_track_sprite[] = {3, 1, 2, 0};
02298       DrawGroundSprite(_corner_to_track_sprite[halftile_corner] + rti->base_sprites.single_n, PALETTE_CRASH, NULL, 0, -(int)TILE_HEIGHT);
02299     }
02300   }
02301 }
02302 
02303 static void DrawSignals(TileIndex tile, TrackBits rails, const RailtypeInfo *rti)
02304 {
02305 #define MAYBE_DRAW_SIGNAL(x, y, z, t) if (IsSignalPresent(tile, x)) DrawSingleSignal(tile, rti, t, GetSingleSignalState(tile, x), y, z)
02306 
02307   if (!(rails & TRACK_BIT_Y)) {
02308     if (!(rails & TRACK_BIT_X)) {
02309       if (rails & TRACK_BIT_LEFT) {
02310         MAYBE_DRAW_SIGNAL(2, SIGNAL_TO_NORTH, 0, TRACK_LEFT);
02311         MAYBE_DRAW_SIGNAL(3, SIGNAL_TO_SOUTH, 1, TRACK_LEFT);
02312       }
02313       if (rails & TRACK_BIT_RIGHT) {
02314         MAYBE_DRAW_SIGNAL(0, SIGNAL_TO_NORTH, 2, TRACK_RIGHT);
02315         MAYBE_DRAW_SIGNAL(1, SIGNAL_TO_SOUTH, 3, TRACK_RIGHT);
02316       }
02317       if (rails & TRACK_BIT_UPPER) {
02318         MAYBE_DRAW_SIGNAL(3, SIGNAL_TO_WEST, 4, TRACK_UPPER);
02319         MAYBE_DRAW_SIGNAL(2, SIGNAL_TO_EAST, 5, TRACK_UPPER);
02320       }
02321       if (rails & TRACK_BIT_LOWER) {
02322         MAYBE_DRAW_SIGNAL(1, SIGNAL_TO_WEST, 6, TRACK_LOWER);
02323         MAYBE_DRAW_SIGNAL(0, SIGNAL_TO_EAST, 7, TRACK_LOWER);
02324       }
02325     } else {
02326       MAYBE_DRAW_SIGNAL(3, SIGNAL_TO_SOUTHWEST, 8, TRACK_X);
02327       MAYBE_DRAW_SIGNAL(2, SIGNAL_TO_NORTHEAST, 9, TRACK_X);
02328     }
02329   } else {
02330     MAYBE_DRAW_SIGNAL(3, SIGNAL_TO_SOUTHEAST, 10, TRACK_Y);
02331     MAYBE_DRAW_SIGNAL(2, SIGNAL_TO_NORTHWEST, 11, TRACK_Y);
02332   }
02333 }
02334 
02335 static void DrawTile_Track(TileInfo *ti)
02336 {
02337   const RailtypeInfo *rti = GetRailTypeInfo(GetRailType(ti->tile));
02338 
02339   _drawtile_track_palette = COMPANY_SPRITE_COLOUR(GetTileOwner(ti->tile));
02340 
02341   if (IsPlainRail(ti->tile)) {
02342     TrackBits rails = GetTrackBits(ti->tile);
02343 
02344     DrawTrackBits(ti, rails);
02345 
02346     if (HasBit(_display_opt, DO_FULL_DETAIL)) DrawTrackDetails(ti, rti);
02347 
02348     if (HasCatenaryDrawn(GetRailType(ti->tile))) DrawCatenary(ti);
02349 
02350     if (HasSignals(ti->tile)) DrawSignals(ti->tile, rails, rti);
02351   } else {
02352     /* draw depot */
02353     const DrawTileSprites *dts;
02354     PaletteID pal = PAL_NONE;
02355     SpriteID relocation;
02356 
02357     if (ti->tileh != SLOPE_FLAT) DrawFoundation(ti, FOUNDATION_LEVELED);
02358 
02359     if (IsInvisibilitySet(TO_BUILDINGS)) {
02360       /* Draw rail instead of depot */
02361       dts = &_depot_invisible_gfx_table[GetRailDepotDirection(ti->tile)];
02362     } else {
02363       dts = &_depot_gfx_table[GetRailDepotDirection(ti->tile)];
02364     }
02365 
02366     SpriteID image;
02367     if (rti->UsesOverlay()) {
02368       image = SPR_FLAT_GRASS_TILE;
02369     } else {
02370       image = dts->ground.sprite;
02371       if (image != SPR_FLAT_GRASS_TILE) image += rti->GetRailtypeSpriteOffset();
02372     }
02373 
02374     /* adjust ground tile for desert
02375      * don't adjust for snow, because snow in depots looks weird */
02376     if (IsSnowRailGround(ti->tile) && _settings_game.game_creation.landscape == LT_TROPIC) {
02377       if (image != SPR_FLAT_GRASS_TILE) {
02378         image += rti->snow_offset; // tile with tracks
02379       } else {
02380         image = SPR_FLAT_SNOW_DESERT_TILE; // flat ground
02381       }
02382     }
02383 
02384     DrawGroundSprite(image, GroundSpritePaletteTransform(image, pal, _drawtile_track_palette));
02385 
02386     if (rti->UsesOverlay()) {
02387       SpriteID ground = GetCustomRailSprite(rti, ti->tile, RTSG_GROUND);
02388 
02389       switch (GetRailDepotDirection(ti->tile)) {
02390         case DIAGDIR_NE: if (!IsInvisibilitySet(TO_BUILDINGS)) break; // else FALL THROUGH
02391         case DIAGDIR_SW: DrawGroundSprite(ground + RTO_X, PAL_NONE); break;
02392         case DIAGDIR_NW: if (!IsInvisibilitySet(TO_BUILDINGS)) break; // else FALL THROUGH
02393         case DIAGDIR_SE: DrawGroundSprite(ground + RTO_Y, PAL_NONE); break;
02394         default: break;
02395       }
02396 
02397       if (_settings_client.gui.show_track_reservation && HasDepotReservation(ti->tile)) {
02398         SpriteID overlay = GetCustomRailSprite(rti, ti->tile, RTSG_OVERLAY);
02399 
02400         switch (GetRailDepotDirection(ti->tile)) {
02401           case DIAGDIR_NE: if (!IsInvisibilitySet(TO_BUILDINGS)) break; // else FALL THROUGH
02402           case DIAGDIR_SW: DrawGroundSprite(overlay + RTO_X, PALETTE_CRASH); break;
02403           case DIAGDIR_NW: if (!IsInvisibilitySet(TO_BUILDINGS)) break; // else FALL THROUGH
02404           case DIAGDIR_SE: DrawGroundSprite(overlay + RTO_Y, PALETTE_CRASH); break;
02405           default: break;
02406         }
02407       }
02408     } else {
02409       /* PBS debugging, draw reserved tracks darker */
02410       if (_game_mode != GM_MENU && _settings_client.gui.show_track_reservation && HasDepotReservation(ti->tile)) {
02411         switch (GetRailDepotDirection(ti->tile)) {
02412           case DIAGDIR_NE: if (!IsInvisibilitySet(TO_BUILDINGS)) break; // else FALL THROUGH
02413           case DIAGDIR_SW: DrawGroundSprite(rti->base_sprites.single_x, PALETTE_CRASH); break;
02414           case DIAGDIR_NW: if (!IsInvisibilitySet(TO_BUILDINGS)) break; // else FALL THROUGH
02415           case DIAGDIR_SE: DrawGroundSprite(rti->base_sprites.single_y, PALETTE_CRASH); break;
02416           default: break;
02417         }
02418       }
02419     }
02420     int depot_sprite = GetCustomRailSprite(rti, ti->tile, RTSG_DEPOT);
02421     relocation = depot_sprite != 0 ? depot_sprite - SPR_RAIL_DEPOT_SE_1 : rti->GetRailtypeSpriteOffset();
02422 
02423     if (HasCatenaryDrawn(GetRailType(ti->tile))) DrawCatenary(ti);
02424 
02425     DrawRailTileSeq(ti, dts, TO_BUILDINGS, relocation, 0, _drawtile_track_palette);
02426   }
02427   DrawBridgeMiddle(ti);
02428 }
02429 
02430 void DrawTrainDepotSprite(int x, int y, int dir, RailType railtype)
02431 {
02432   const DrawTileSprites *dts = &_depot_gfx_table[dir];
02433   const RailtypeInfo *rti = GetRailTypeInfo(railtype);
02434   SpriteID image = rti->UsesOverlay() ? SPR_FLAT_GRASS_TILE : dts->ground.sprite;
02435   uint32 offset = rti->GetRailtypeSpriteOffset();
02436 
02437   x += 33;
02438   y += 17;
02439 
02440   if (image != SPR_FLAT_GRASS_TILE) image += offset;
02441   PaletteID palette = COMPANY_SPRITE_COLOUR(_local_company);
02442 
02443   DrawSprite(image, PAL_NONE, x, y);
02444 
02445   if (rti->UsesOverlay()) {
02446     SpriteID ground = GetCustomRailSprite(rti, INVALID_TILE, RTSG_GROUND);
02447 
02448     switch (dir) {
02449       case DIAGDIR_SW: DrawSprite(ground + RTO_X, PAL_NONE, x, y); break;
02450       case DIAGDIR_SE: DrawSprite(ground + RTO_Y, PAL_NONE, x, y); break;
02451       default: break;
02452     }
02453   }
02454   int depot_sprite = GetCustomRailSprite(rti, INVALID_TILE, RTSG_DEPOT);
02455   if (depot_sprite != 0) offset = depot_sprite - SPR_RAIL_DEPOT_SE_1;
02456 
02457   DrawRailTileSeqInGUI(x, y, dts, offset, 0, palette);
02458 }
02459 
02460 static int GetSlopePixelZ_Track(TileIndex tile, uint x, uint y)
02461 {
02462   if (IsPlainRail(tile)) {
02463     int z;
02464     Slope tileh = GetTilePixelSlope(tile, &z);
02465     if (tileh == SLOPE_FLAT) return z;
02466 
02467     z += ApplyPixelFoundationToSlope(GetRailFoundation(tileh, GetTrackBits(tile)), &tileh);
02468     return z + GetPartialPixelZ(x & 0xF, y & 0xF, tileh);
02469   } else {
02470     return GetTileMaxPixelZ(tile);
02471   }
02472 }
02473 
02474 static Foundation GetFoundation_Track(TileIndex tile, Slope tileh)
02475 {
02476   return IsPlainRail(tile) ? GetRailFoundation(tileh, GetTrackBits(tile)) : FlatteningFoundation(tileh);
02477 }
02478 
02479 static void TileLoop_Track(TileIndex tile)
02480 {
02481   RailGroundType old_ground = GetRailGroundType(tile);
02482   RailGroundType new_ground;
02483 
02484   if (old_ground == RAIL_GROUND_WATER) {
02485     TileLoop_Water(tile);
02486     return;
02487   }
02488 
02489   switch (_settings_game.game_creation.landscape) {
02490     case LT_ARCTIC: {
02491       int z;
02492       Slope slope = GetTileSlope(tile, &z);
02493       bool half = false;
02494 
02495       /* for non-flat track, use lower part of track
02496        * in other cases, use the highest part with track */
02497       if (IsPlainRail(tile)) {
02498         TrackBits track = GetTrackBits(tile);
02499         Foundation f = GetRailFoundation(slope, track);
02500 
02501         switch (f) {
02502           case FOUNDATION_NONE:
02503             /* no foundation - is the track on the upper side of three corners raised tile? */
02504             if (IsSlopeWithThreeCornersRaised(slope)) z++;
02505             break;
02506 
02507           case FOUNDATION_INCLINED_X:
02508           case FOUNDATION_INCLINED_Y:
02509             /* sloped track - is it on a steep slope? */
02510             if (IsSteepSlope(slope)) z++;
02511             break;
02512 
02513           case FOUNDATION_STEEP_LOWER:
02514             /* only lower part of steep slope */
02515             z++;
02516             break;
02517 
02518           default:
02519             /* if it is a steep slope, then there is a track on higher part */
02520             if (IsSteepSlope(slope)) z++;
02521             z++;
02522             break;
02523         }
02524 
02525         half = IsInsideMM(f, FOUNDATION_STEEP_BOTH, FOUNDATION_HALFTILE_N + 1);
02526       } else {
02527         /* is the depot on a non-flat tile? */
02528         if (slope != SLOPE_FLAT) z++;
02529       }
02530 
02531       /* 'z' is now the lowest part of the highest track bit -
02532        * for sloped track, it is 'z' of lower part
02533        * for two track bits, it is 'z' of higher track bit
02534        * For non-continuous foundations (and STEEP_BOTH), 'half' is set */
02535       if (z > GetSnowLine()) {
02536         if (half && z - GetSnowLine() == 1) {
02537           /* track on non-continuous foundation, lower part is not under snow */
02538           new_ground = RAIL_GROUND_HALF_SNOW;
02539         } else {
02540           new_ground = RAIL_GROUND_ICE_DESERT;
02541         }
02542         goto set_ground;
02543       }
02544       break;
02545       }
02546 
02547     case LT_TROPIC:
02548       if (GetTropicZone(tile) == TROPICZONE_DESERT) {
02549         new_ground = RAIL_GROUND_ICE_DESERT;
02550         goto set_ground;
02551       }
02552       break;
02553   }
02554 
02555   new_ground = RAIL_GROUND_GRASS;
02556 
02557   if (IsPlainRail(tile) && old_ground != RAIL_GROUND_BARREN) { // wait until bottom is green
02558     /* determine direction of fence */
02559     TrackBits rail = GetTrackBits(tile);
02560 
02561     Owner owner = GetTileOwner(tile);
02562     byte fences = 0;
02563 
02564     for (DiagDirection d = DIAGDIR_BEGIN; d < DIAGDIR_END; d++) {
02565       static const TrackBits dir_to_trackbits[DIAGDIR_END] = {TRACK_BIT_3WAY_NE, TRACK_BIT_3WAY_SE, TRACK_BIT_3WAY_SW, TRACK_BIT_3WAY_NW};
02566 
02567       /* Track bit on this edge => no fence. */
02568       if ((rail & dir_to_trackbits[d]) != TRACK_BIT_NONE) continue;
02569 
02570       TileIndex tile2 = tile + TileOffsByDiagDir(d);
02571 
02572       /* Show fences if it's a house, industry, road, tunnelbridge or not owned by us. */
02573       if (!IsValidTile(tile2) || IsTileType(tile2, MP_HOUSE) || IsTileType(tile2, MP_INDUSTRY) ||
02574           IsTileType(tile2, MP_ROAD) || IsTileType(tile2, MP_TUNNELBRIDGE) || !IsTileOwner(tile2, owner)) {
02575         fences |= 1 << d;
02576       }
02577     }
02578 
02579     switch (fences) {
02580       case 0: break;
02581       case (1 << DIAGDIR_NE): new_ground = RAIL_GROUND_FENCE_NE; break;
02582       case (1 << DIAGDIR_SE): new_ground = RAIL_GROUND_FENCE_SE; break;
02583       case (1 << DIAGDIR_SW): new_ground = RAIL_GROUND_FENCE_SW; break;
02584       case (1 << DIAGDIR_NW): new_ground = RAIL_GROUND_FENCE_NW; break;
02585       case (1 << DIAGDIR_NE) | (1 << DIAGDIR_SW): new_ground = RAIL_GROUND_FENCE_NESW; break;
02586       case (1 << DIAGDIR_SE) | (1 << DIAGDIR_NW): new_ground = RAIL_GROUND_FENCE_SENW; break;
02587       case (1 << DIAGDIR_NE) | (1 << DIAGDIR_SE): new_ground = RAIL_GROUND_FENCE_VERT1; break;
02588       case (1 << DIAGDIR_NE) | (1 << DIAGDIR_NW): new_ground = RAIL_GROUND_FENCE_HORIZ2; break;
02589       case (1 << DIAGDIR_SE) | (1 << DIAGDIR_SW): new_ground = RAIL_GROUND_FENCE_HORIZ1; break;
02590       case (1 << DIAGDIR_SW) | (1 << DIAGDIR_NW): new_ground = RAIL_GROUND_FENCE_VERT2; break;
02591       default: NOT_REACHED();
02592     }
02593   }
02594 
02595 set_ground:
02596   if (old_ground != new_ground) {
02597     SetRailGroundType(tile, new_ground);
02598     MarkTileDirtyByTile(tile);
02599   }
02600 }
02601 
02602 
02603 static TrackStatus GetTileTrackStatus_Track(TileIndex tile, TransportType mode, uint sub_mode, DiagDirection side)
02604 {
02605   /* Case of half tile slope with water. */
02606   if (mode == TRANSPORT_WATER && IsPlainRail(tile) && GetRailGroundType(tile) == RAIL_GROUND_WATER && IsSlopeWithOneCornerRaised(GetTileSlope(tile))) {
02607     TrackBits tb = GetTrackBits(tile);
02608     switch (tb) {
02609       default: NOT_REACHED();
02610       case TRACK_BIT_UPPER: tb = TRACK_BIT_LOWER; break;
02611       case TRACK_BIT_LOWER: tb = TRACK_BIT_UPPER; break;
02612       case TRACK_BIT_LEFT:  tb = TRACK_BIT_RIGHT; break;
02613       case TRACK_BIT_RIGHT: tb = TRACK_BIT_LEFT;  break;
02614     }
02615     return CombineTrackStatus(TrackBitsToTrackdirBits(tb), TRACKDIR_BIT_NONE);
02616   }
02617 
02618   if (mode != TRANSPORT_RAIL) return 0;
02619 
02620   TrackBits trackbits = TRACK_BIT_NONE;
02621   TrackdirBits red_signals = TRACKDIR_BIT_NONE;
02622 
02623   switch (GetRailTileType(tile)) {
02624     default: NOT_REACHED();
02625     case RAIL_TILE_NORMAL:
02626       trackbits = GetTrackBits(tile);
02627       break;
02628 
02629     case RAIL_TILE_SIGNALS: {
02630       trackbits = GetTrackBits(tile);
02631       byte a = GetPresentSignals(tile);
02632       uint b = GetSignalStates(tile);
02633 
02634       b &= a;
02635 
02636       /* When signals are not present (in neither direction),
02637        * we pretend them to be green. Otherwise, it depends on
02638        * the signal type. For signals that are only active from
02639        * one side, we set the missing signals explicitly to
02640        * `green'. Otherwise, they implicitly become `red'. */
02641       if (!IsOnewaySignal(tile, TRACK_UPPER) || (a & SignalOnTrack(TRACK_UPPER)) == 0) b |= ~a & SignalOnTrack(TRACK_UPPER);
02642       if (!IsOnewaySignal(tile, TRACK_LOWER) || (a & SignalOnTrack(TRACK_LOWER)) == 0) b |= ~a & SignalOnTrack(TRACK_LOWER);
02643 
02644       if ((b & 0x8) == 0) red_signals |= (TRACKDIR_BIT_LEFT_N | TRACKDIR_BIT_X_NE | TRACKDIR_BIT_Y_SE | TRACKDIR_BIT_UPPER_E);
02645       if ((b & 0x4) == 0) red_signals |= (TRACKDIR_BIT_LEFT_S | TRACKDIR_BIT_X_SW | TRACKDIR_BIT_Y_NW | TRACKDIR_BIT_UPPER_W);
02646       if ((b & 0x2) == 0) red_signals |= (TRACKDIR_BIT_RIGHT_N | TRACKDIR_BIT_LOWER_E);
02647       if ((b & 0x1) == 0) red_signals |= (TRACKDIR_BIT_RIGHT_S | TRACKDIR_BIT_LOWER_W);
02648 
02649       break;
02650     }
02651 
02652     case RAIL_TILE_DEPOT: {
02653       DiagDirection dir = GetRailDepotDirection(tile);
02654 
02655       if (side != INVALID_DIAGDIR && side != dir) break;
02656 
02657       trackbits = DiagDirToDiagTrackBits(dir);
02658       break;
02659     }
02660   }
02661 
02662   return CombineTrackStatus(TrackBitsToTrackdirBits(trackbits), red_signals);
02663 }
02664 
02665 static bool ClickTile_Track(TileIndex tile)
02666 {
02667   if (!IsRailDepot(tile)) return false;
02668 
02669   ShowDepotWindow(tile, VEH_TRAIN);
02670   return true;
02671 }
02672 
02673 static void GetTileDesc_Track(TileIndex tile, TileDesc *td)
02674 {
02675   const RailtypeInfo *rti = GetRailTypeInfo(GetRailType(tile));
02676   td->rail_speed = rti->max_speed;
02677   td->owner[0] = GetTileOwner(tile);
02678   SetDParamX(td->dparam, 0, rti->strings.name);
02679   switch (GetRailTileType(tile)) {
02680     case RAIL_TILE_NORMAL:
02681       td->str = STR_LAI_RAIL_DESCRIPTION_TRACK;
02682       break;
02683 
02684     case RAIL_TILE_SIGNALS: {
02685       static const StringID signal_type[6][6] = {
02686         {
02687           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_NORMAL_SIGNALS,
02688           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_NORMAL_PRESIGNALS,
02689           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_NORMAL_EXITSIGNALS,
02690           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_NORMAL_COMBOSIGNALS,
02691           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_NORMAL_PBSSIGNALS,
02692           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_NORMAL_NOENTRYSIGNALS
02693         },
02694         {
02695           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_NORMAL_PRESIGNALS,
02696           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_PRESIGNALS,
02697           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_PRE_EXITSIGNALS,
02698           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_PRE_COMBOSIGNALS,
02699           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_PRE_PBSSIGNALS,
02700           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_PRE_NOENTRYSIGNALS
02701         },
02702         {
02703           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_NORMAL_EXITSIGNALS,
02704           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_PRE_EXITSIGNALS,
02705           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_EXITSIGNALS,
02706           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_EXIT_COMBOSIGNALS,
02707           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_EXIT_PBSSIGNALS,
02708           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_EXIT_NOENTRYSIGNALS
02709         },
02710         {
02711           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_NORMAL_COMBOSIGNALS,
02712           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_PRE_COMBOSIGNALS,
02713           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_EXIT_COMBOSIGNALS,
02714           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_COMBOSIGNALS,
02715           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_COMBO_PBSSIGNALS,
02716           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_COMBO_NOENTRYSIGNALS
02717         },
02718         {
02719           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_NORMAL_PBSSIGNALS,
02720           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_PRE_PBSSIGNALS,
02721           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_EXIT_PBSSIGNALS,
02722           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_COMBO_PBSSIGNALS,
02723           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_PBSSIGNALS,
02724           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_PBS_NOENTRYSIGNALS
02725         },
02726         {
02727           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_NORMAL_NOENTRYSIGNALS,
02728           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_PRE_NOENTRYSIGNALS,
02729           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_EXIT_NOENTRYSIGNALS,
02730           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_COMBO_NOENTRYSIGNALS,
02731           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_PBS_NOENTRYSIGNALS,
02732           STR_LAI_RAIL_DESCRIPTION_TRACK_WITH_NOENTRYSIGNALS
02733         }
02734       };
02735 
02736       SignalType primary_signal;
02737       SignalType secondary_signal;
02738       if (HasSignalOnTrack(tile, TRACK_UPPER)) {
02739         primary_signal = GetSignalType(tile, TRACK_UPPER);
02740         secondary_signal = HasSignalOnTrack(tile, TRACK_LOWER) ? GetSignalType(tile, TRACK_LOWER) : primary_signal;
02741       } else {
02742         secondary_signal = primary_signal = GetSignalType(tile, TRACK_LOWER);
02743       }
02744 
02745       td->str = signal_type[secondary_signal][primary_signal];
02746       break;
02747     }
02748 
02749     case RAIL_TILE_DEPOT:
02750       td->str = STR_LAI_RAIL_DESCRIPTION_TRAIN_DEPOT;
02751       if (_settings_game.vehicle.train_acceleration_model != AM_ORIGINAL) {
02752         if (td->rail_speed > 0) {
02753           td->rail_speed = min(td->rail_speed, 61);
02754         } else {
02755           td->rail_speed = 61;
02756         }
02757       }
02758       td->build_date = Depot::GetByTile(tile)->build_date;
02759       break;
02760 
02761     default:
02762       NOT_REACHED();
02763   }
02764 }
02765 
02766 static void ChangeTileOwner_Track(TileIndex tile, Owner old_owner, Owner new_owner)
02767 {
02768   if (!IsTileOwner(tile, old_owner)) return;
02769 
02770   if (new_owner != INVALID_OWNER) {
02771     /* Update company infrastructure counts. No need to dirty windows here, we'll redraw the whole screen anyway. */
02772     uint num_pieces = 1;
02773     if (IsPlainRail(tile)) {
02774       TrackBits bits = GetTrackBits(tile);
02775       num_pieces = CountBits(bits);
02776       if (TracksOverlap(bits)) num_pieces *= num_pieces;
02777     }
02778     RailType rt = GetRailType(tile);
02779     Company::Get(old_owner)->infrastructure.rail[rt] -= num_pieces;
02780     Company::Get(new_owner)->infrastructure.rail[rt] += num_pieces;
02781 
02782     if (HasSignals(tile)) {
02783       uint num_sigs = CountBits(GetPresentSignals(tile));
02784       Company::Get(old_owner)->infrastructure.signal -= num_sigs;
02785       Company::Get(new_owner)->infrastructure.signal += num_sigs;
02786     }
02787 
02788     SetTileOwner(tile, new_owner);
02789   } else {
02790     DoCommand(tile, 0, 0, DC_EXEC | DC_BANKRUPT, CMD_LANDSCAPE_CLEAR);
02791   }
02792 }
02793 
02794 static const byte _fractcoords_behind[4] = { 0x8F, 0x8, 0x80, 0xF8 };
02795 static const byte _fractcoords_enter[4] = { 0x8A, 0x48, 0x84, 0xA8 };
02796 static const int8 _deltacoord_leaveoffset[8] = {
02797   -1,  0,  1,  0, /* x */
02798    0,  1,  0, -1  /* y */
02799 };
02800 
02801 
02808 int TicksToLeaveDepot(const Train *v)
02809 {
02810   DiagDirection dir = GetRailDepotDirection(v->tile);
02811   int length = v->CalcNextVehicleOffset();
02812 
02813   switch (dir) {
02814     case DIAGDIR_NE: return  ((int)(v->x_pos & 0x0F) - ((_fractcoords_enter[dir] & 0x0F) - (length + 1)));
02815     case DIAGDIR_SE: return -((int)(v->y_pos & 0x0F) - ((_fractcoords_enter[dir] >> 4)   + (length + 1)));
02816     case DIAGDIR_SW: return -((int)(v->x_pos & 0x0F) - ((_fractcoords_enter[dir] & 0x0F) + (length + 1)));
02817     default:
02818     case DIAGDIR_NW: return  ((int)(v->y_pos & 0x0F) - ((_fractcoords_enter[dir] >> 4)   - (length + 1)));
02819   }
02820 
02821   return 0; // make compilers happy
02822 }
02823 
02828 static VehicleEnterTileStatus VehicleEnter_Track(Vehicle *u, TileIndex tile, int x, int y)
02829 {
02830   /* this routine applies only to trains in depot tiles */
02831   if (u->type != VEH_TRAIN || !IsRailDepotTile(tile)) return VETSB_CONTINUE;
02832 
02833   Train *v = Train::From(u);
02834 
02835   /* depot direction */
02836   DiagDirection dir = GetRailDepotDirection(tile);
02837 
02838   /* Calculate the point where the following wagon should be activated. */
02839   int length = v->CalcNextVehicleOffset();
02840 
02841   byte fract_coord_leave =
02842     ((_fractcoords_enter[dir] & 0x0F) + // x
02843       (length + 1) * _deltacoord_leaveoffset[dir]) +
02844     (((_fractcoords_enter[dir] >> 4) +  // y
02845       ((length + 1) * _deltacoord_leaveoffset[dir + 4])) << 4);
02846 
02847   byte fract_coord = (x & 0xF) + ((y & 0xF) << 4);
02848 
02849   if (_fractcoords_behind[dir] == fract_coord) {
02850     /* make sure a train is not entering the tile from behind */
02851     return VETSB_CANNOT_ENTER;
02852   } else if (_fractcoords_enter[dir] == fract_coord) {
02853     if (DiagDirToDir(ReverseDiagDir(dir)) == v->direction) {
02854       /* enter the depot */
02855       v->track = TRACK_BIT_DEPOT,
02856       v->vehstatus |= VS_HIDDEN; // hide it
02857       v->direction = ReverseDir(v->direction);
02858       if (v->Next() == NULL) VehicleEnterDepot(v->First());
02859       v->tile = tile;
02860 
02861       InvalidateWindowData(WC_VEHICLE_DEPOT, v->tile);
02862       return VETSB_ENTERED_WORMHOLE;
02863     }
02864   } else if (fract_coord_leave == fract_coord) {
02865     if (DiagDirToDir(dir) == v->direction) {
02866       /* leave the depot? */
02867       if ((v = v->Next()) != NULL) {
02868         v->vehstatus &= ~VS_HIDDEN;
02869         v->track = (DiagDirToAxis(dir) == AXIS_X ? TRACK_BIT_X : TRACK_BIT_Y);
02870       }
02871     }
02872   }
02873 
02874   return VETSB_CONTINUE;
02875 }
02876 
02888 static CommandCost TestAutoslopeOnRailTile(TileIndex tile, uint flags, int z_old, Slope tileh_old, int z_new, Slope tileh_new, TrackBits rail_bits)
02889 {
02890   if (!_settings_game.construction.build_on_slopes || !AutoslopeEnabled()) return_cmd_error(STR_ERROR_MUST_REMOVE_RAILROAD_TRACK);
02891 
02892   /* Is the slope-rail_bits combination valid in general? I.e. is it safe to call GetRailFoundation() ? */
02893   if (CheckRailSlope(tileh_new, rail_bits, TRACK_BIT_NONE, tile).Failed()) return_cmd_error(STR_ERROR_MUST_REMOVE_RAILROAD_TRACK);
02894 
02895   /* Get the slopes on top of the foundations */
02896   z_old += ApplyFoundationToSlope(GetRailFoundation(tileh_old, rail_bits), &tileh_old);
02897   z_new += ApplyFoundationToSlope(GetRailFoundation(tileh_new, rail_bits), &tileh_new);
02898 
02899   Corner track_corner;
02900   switch (rail_bits) {
02901     case TRACK_BIT_LEFT:  track_corner = CORNER_W; break;
02902     case TRACK_BIT_LOWER: track_corner = CORNER_S; break;
02903     case TRACK_BIT_RIGHT: track_corner = CORNER_E; break;
02904     case TRACK_BIT_UPPER: track_corner = CORNER_N; break;
02905 
02906     /* Surface slope must not be changed */
02907     default:
02908       if (z_old != z_new || tileh_old != tileh_new) return_cmd_error(STR_ERROR_MUST_REMOVE_RAILROAD_TRACK);
02909       return CommandCost(EXPENSES_CONSTRUCTION, _price[PR_BUILD_FOUNDATION]);
02910   }
02911 
02912   /* The height of the track_corner must not be changed. The rest ensures GetRailFoundation() already. */
02913   z_old += GetSlopeZInCorner(RemoveHalftileSlope(tileh_old), track_corner);
02914   z_new += GetSlopeZInCorner(RemoveHalftileSlope(tileh_new), track_corner);
02915   if (z_old != z_new) return_cmd_error(STR_ERROR_MUST_REMOVE_RAILROAD_TRACK);
02916 
02917   CommandCost cost = CommandCost(EXPENSES_CONSTRUCTION, _price[PR_BUILD_FOUNDATION]);
02918   /* Make the ground dirty, if surface slope has changed */
02919   if (tileh_old != tileh_new) {
02920     /* If there is flat water on the lower halftile add the cost for clearing it */
02921     if (GetRailGroundType(tile) == RAIL_GROUND_WATER && IsSlopeWithOneCornerRaised(tileh_old)) cost.AddCost(_price[PR_CLEAR_WATER]);
02922     if ((flags & DC_EXEC) != 0) SetRailGroundType(tile, RAIL_GROUND_BARREN);
02923   }
02924   return  cost;
02925 }
02926 
02930 static Vehicle *EnsureNoShipProc(Vehicle *v, void *data)
02931 {
02932   return v->type == VEH_SHIP ? v : NULL;
02933 }
02934 
02935 static CommandCost TerraformTile_Track(TileIndex tile, DoCommandFlag flags, int z_new, Slope tileh_new)
02936 {
02937   int z_old;
02938   Slope tileh_old = GetTileSlope(tile, &z_old);
02939   if (IsPlainRail(tile)) {
02940     TrackBits rail_bits = GetTrackBits(tile);
02941     /* Is there flat water on the lower halftile that must be cleared expensively? */
02942     bool was_water = (GetRailGroundType(tile) == RAIL_GROUND_WATER && IsSlopeWithOneCornerRaised(tileh_old));
02943 
02944     /* Allow clearing the water only if there is no ship */
02945     if (was_water && HasVehicleOnPos(tile, NULL, &EnsureNoShipProc)) return_cmd_error(STR_ERROR_SHIP_IN_THE_WAY);
02946 
02947     /* First test autoslope. However if it succeeds we still have to test the rest, because non-autoslope terraforming is cheaper. */
02948     CommandCost autoslope_result = TestAutoslopeOnRailTile(tile, flags, z_old, tileh_old, z_new, tileh_new, rail_bits);
02949 
02950     /* When there is only a single horizontal/vertical track, one corner can be terraformed. */
02951     Corner allowed_corner;
02952     switch (rail_bits) {
02953       case TRACK_BIT_RIGHT: allowed_corner = CORNER_W; break;
02954       case TRACK_BIT_UPPER: allowed_corner = CORNER_S; break;
02955       case TRACK_BIT_LEFT:  allowed_corner = CORNER_E; break;
02956       case TRACK_BIT_LOWER: allowed_corner = CORNER_N; break;
02957       default: return autoslope_result;
02958     }
02959 
02960     Foundation f_old = GetRailFoundation(tileh_old, rail_bits);
02961 
02962     /* Do not allow terraforming if allowed_corner is part of anti-zig-zag foundations */
02963     if (tileh_old != SLOPE_NS && tileh_old != SLOPE_EW && IsSpecialRailFoundation(f_old)) return autoslope_result;
02964 
02965     /* Everything is valid, which only changes allowed_corner */
02966     for (Corner corner = (Corner)0; corner < CORNER_END; corner = (Corner)(corner + 1)) {
02967       if (allowed_corner == corner) continue;
02968       if (z_old + GetSlopeZInCorner(tileh_old, corner) != z_new + GetSlopeZInCorner(tileh_new, corner)) return autoslope_result;
02969     }
02970 
02971     /* Make the ground dirty */
02972     if ((flags & DC_EXEC) != 0) SetRailGroundType(tile, RAIL_GROUND_BARREN);
02973 
02974     /* allow terraforming */
02975     return CommandCost(EXPENSES_CONSTRUCTION, was_water ? _price[PR_CLEAR_WATER] : (Money)0);
02976   } else if (_settings_game.construction.build_on_slopes && AutoslopeEnabled() &&
02977       AutoslopeCheckForEntranceEdge(tile, z_new, tileh_new, GetRailDepotDirection(tile))) {
02978     return CommandCost(EXPENSES_CONSTRUCTION, _price[PR_BUILD_FOUNDATION]);
02979   }
02980   return DoCommand(tile, 0, 0, flags, CMD_LANDSCAPE_CLEAR);
02981 }
02982 
02983 
02984 extern const TileTypeProcs _tile_type_rail_procs = {
02985   DrawTile_Track,           // draw_tile_proc
02986   GetSlopePixelZ_Track,     // get_slope_z_proc
02987   ClearTile_Track,          // clear_tile_proc
02988   NULL,                     // add_accepted_cargo_proc
02989   GetTileDesc_Track,        // get_tile_desc_proc
02990   GetTileTrackStatus_Track, // get_tile_track_status_proc
02991   ClickTile_Track,          // click_tile_proc
02992   NULL,                     // animate_tile_proc
02993   TileLoop_Track,           // tile_loop_proc
02994   ChangeTileOwner_Track,    // change_tile_owner_proc
02995   NULL,                     // add_produced_cargo_proc
02996   VehicleEnter_Track,       // vehicle_enter_tile_proc
02997   GetFoundation_Track,      // get_foundation_proc
02998   TerraformTile_Track,      // terraform_tile_proc
02999 };