# ai_rail.cpp

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    00001 /* $Id: ai_rail.cpp 18987 2010-02-02 22:27:03Z terkhen $ */
    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 "ai_rail.hpp"
    00013 #include "ai_map.hpp"
    00014 #include "ai_station.hpp"
    00015 #include "../../command_type.h"
    00016 #include "../../debug.h"
    00017 #include "../../station_base.h"
    00018 #include "../../company_func.h"
    00019 #include "../../newgrf.h"
    00020 #include "../../newgrf_generic.h"
    00021 #include "../../newgrf_station.h"
    00022 #include "../../economy_func.h"
    00023
    00024 /* static */ bool AIRail::IsRailTile(TileIndex tile)
    00025 {
    00026   if (!::IsValidTile(tile)) return false;
    00027
    00028   return (::IsTileType(tile, MP_RAILWAY) && !::IsRailDepot(tile)) ||
    00029       (::HasStationTileRail(tile) && !::IsStationTileBlocked(tile)) || ::IsLevelCrossingTile(tile);
    00030 }
    00031
    00032 /* static */ bool AIRail::IsLevelCrossingTile(TileIndex tile)
    00033 {
    00034   if (!::IsValidTile(tile)) return false;
    00035
    00036   return ::IsLevelCrossingTile(tile);
    00037 }
    00038
    00039 /* static */ bool AIRail::IsRailDepotTile(TileIndex tile)
    00040 {
    00041   if (!::IsValidTile(tile)) return false;
    00042
    00043   return ::IsRailDepotTile(tile);
    00044 }
    00045
    00046 /* static */ bool AIRail::IsRailStationTile(TileIndex tile)
    00047 {
    00048   if (!::IsValidTile(tile)) return false;
    00049
    00050   return ::IsRailStationTile(tile);
    00051 }
    00052
    00053 /* static */ bool AIRail::IsRailWaypointTile(TileIndex tile)
    00054 {
    00055   if (!::IsValidTile(tile)) return false;
    00056
    00057   return ::IsRailWaypointTile(tile);
    00058 }
    00059
    00060 /* static */ bool AIRail::IsRailTypeAvailable(RailType rail_type)
    00061 {
    00062   if ((::RailType)rail_type < RAILTYPE_BEGIN || (::RailType)rail_type >= RAILTYPE_END) return false;
    00063
    00064   return ::HasRailtypeAvail(_current_company, (::RailType)rail_type);
    00065 }
    00066
    00067 /* static */ AIRail::RailType AIRail::GetCurrentRailType()
    00068 {
    00069   return (RailType)AIObject::GetRailType();
    00070 }
    00071
    00072 /* static */ void AIRail::SetCurrentRailType(RailType rail_type)
    00073 {
    00074   if (!IsRailTypeAvailable(rail_type)) return;
    00075
    00076   AIObject::SetRailType((::RailType)rail_type);
    00077 }
    00078
    00079 /* static */ bool AIRail::TrainCanRunOnRail(AIRail::RailType engine_rail_type, AIRail::RailType track_rail_type)
    00080 {
    00081   if (!AIRail::IsRailTypeAvailable(engine_rail_type)) return false;
    00082   if (!AIRail::IsRailTypeAvailable(track_rail_type)) return false;
    00083
    00084   return ::IsCompatibleRail((::RailType)engine_rail_type, (::RailType)track_rail_type);
    00085 }
    00086
    00087 /* static */ bool AIRail::TrainHasPowerOnRail(AIRail::RailType engine_rail_type, AIRail::RailType track_rail_type)
    00088 {\
    00089   if (!AIRail::IsRailTypeAvailable(engine_rail_type)) return false;
    00090   if (!AIRail::IsRailTypeAvailable(track_rail_type)) return false;
    00091
    00092   return ::HasPowerOnRail((::RailType)engine_rail_type, (::RailType)track_rail_type);
    00093 }
    00094
    00095 /* static */ AIRail::RailType AIRail::GetRailType(TileIndex tile)
    00096 {
    00097   if (!AITile::HasTransportType(tile, AITile::TRANSPORT_RAIL)) return RAILTYPE_INVALID;
    00098
    00099   return (RailType)::GetRailType(tile);
    00100 }
    00101
    00102 /* static */ bool AIRail::ConvertRailType(TileIndex start_tile, TileIndex end_tile, AIRail::RailType convert_to)
    00103 {
    00104   EnforcePrecondition(false, ::IsValidTile(start_tile));
    00105   EnforcePrecondition(false, ::IsValidTile(end_tile));
    00106   EnforcePrecondition(false, IsRailTypeAvailable(convert_to));
    00107
    00108   return AIObject::DoCommand(start_tile, end_tile, convert_to, CMD_CONVERT_RAIL);
    00109 }
    00110
    00111 /* static */ TileIndex AIRail::GetRailDepotFrontTile(TileIndex depot)
    00112 {
    00113   if (!IsRailDepotTile(depot)) return INVALID_TILE;
    00114
    00115   return depot + ::TileOffsByDiagDir(::GetRailDepotDirection(depot));
    00116 }
    00117
    00118 /* static */ AIRail::RailTrack AIRail::GetRailStationDirection(TileIndex tile)
    00119 {
    00120   if (!IsRailStationTile(tile)) return RAILTRACK_INVALID;
    00121
    00122   return (RailTrack)::GetRailStationTrackBits(tile);
    00123 }
    00124
    00125 /* static */ bool AIRail::BuildRailDepot(TileIndex tile, TileIndex front)
    00126 {
    00127   EnforcePrecondition(false, tile != front);
    00128   EnforcePrecondition(false, ::IsValidTile(tile));
    00129   EnforcePrecondition(false, ::IsValidTile(front));
    00130   EnforcePrecondition(false, ::TileX(tile) == ::TileX(front) || ::TileY(tile) == ::TileY(front));
    00131   EnforcePrecondition(false, IsRailTypeAvailable(GetCurrentRailType()));
    00132
    00133   uint entrance_dir = (::TileX(tile) == ::TileX(front)) ? (::TileY(tile) < ::TileY(front) ? 1 : 3) : (::TileX(tile) < ::TileX(front) ? 2 : 0);
    00134
    00135   return AIObject::DoCommand(tile, AIObject::GetRailType(), entrance_dir, CMD_BUILD_TRAIN_DEPOT);
    00136 }
    00137
    00138 /* static */ bool AIRail::BuildRailStation(TileIndex tile, RailTrack direction, uint num_platforms, uint platform_length, StationID station_id)
    00139 {
    00140   EnforcePrecondition(false, ::IsValidTile(tile));
    00141   EnforcePrecondition(false, direction == RAILTRACK_NW_SE || direction == RAILTRACK_NE_SW);
    00142   EnforcePrecondition(false, num_platforms > 0 && num_platforms <= 0xFF);
    00143   EnforcePrecondition(false, platform_length > 0 && platform_length <= 0xFF);
    00144   EnforcePrecondition(false, IsRailTypeAvailable(GetCurrentRailType()));
    00145   EnforcePrecondition(false, station_id == AIStation::STATION_NEW || station_id == AIStation::STATION_JOIN_ADJACENT || AIStation::IsValidStation(station_id));
    00146
    00147   uint32 p1 = GetCurrentRailType() | (platform_length << 16) | (num_platforms << 8);
    00148   if (direction == RAILTRACK_NW_SE) p1 |= (1 << 4);
    00149   if (station_id != AIStation::STATION_JOIN_ADJACENT) p1 |= (1 << 24);
    00150   return AIObject::DoCommand(tile, p1, (AIStation::IsValidStation(station_id) ? station_id : INVALID_STATION) << 16, CMD_BUILD_RAIL_STATION);
    00151 }
    00152
    00153 /* static */ bool AIRail::BuildNewGRFRailStation(TileIndex tile, RailTrack direction, uint num_platforms, uint platform_length, StationID station_id, CargoID cargo_id, IndustryType source_industry, IndustryType goal_industry, int distance, bool source_station)
    00154 {
    00155   EnforcePrecondition(false, ::IsValidTile(tile));
    00156   EnforcePrecondition(false, direction == RAILTRACK_NW_SE || direction == RAILTRACK_NE_SW);
    00157   EnforcePrecondition(false, num_platforms > 0 && num_platforms <= 0xFF);
    00158   EnforcePrecondition(false, platform_length > 0 && platform_length <= 0xFF);
    00159   EnforcePrecondition(false, IsRailTypeAvailable(GetCurrentRailType()));
    00160   EnforcePrecondition(false, station_id == AIStation::STATION_NEW || station_id == AIStation::STATION_JOIN_ADJACENT || AIStation::IsValidStation(station_id));
    00161
    00162   uint32 p1 = GetCurrentRailType() | (platform_length << 16) | (num_platforms << 8);
    00163   if (direction == RAILTRACK_NW_SE) p1 |= 1 << 4;
    00164   if (station_id != AIStation::STATION_JOIN_ADJACENT) p1 |= (1 << 24);
    00165
    00166   const GRFFile *file;
    00167   uint16 res = GetAiPurchaseCallbackResult(GSF_STATION, cargo_id, 0, source_industry, goal_industry, min(255, distance / 2), AICE_STATION_GET_STATION_ID, source_station ? 0 : 1, min(15, num_platforms) << 4 | min(15, platform_length), &file);
    00168   uint32 p2 = (AIStation::IsValidStation(station_id) ? station_id : INVALID_STATION) << 16;
    00169   if (res != CALLBACK_FAILED) {
    00170     int index = 0;
    00171     const StationSpec *spec = GetCustomStationSpecByGrf(file->grfid, res, &index);
    00172     if (spec == NULL) {
    00173       DEBUG(grf, 1, "%s returned an invalid station ID for 'AI construction/purchase selection (18)' callback", file->filename);
    00174     } else {
    00175       p2 |= spec->sclass | index << 8;
    00176     }
    00177
    00178   }
    00179   return AIObject::DoCommand(tile, p1, p2, CMD_BUILD_RAIL_STATION);
    00180 }
    00181
    00182 /* static */ bool AIRail::BuildRailWaypoint(TileIndex tile)
    00183 {
    00184   EnforcePrecondition(false, ::IsValidTile(tile));
    00185   EnforcePrecondition(false, IsRailTile(tile));
    00186   EnforcePrecondition(false, GetRailTracks(tile) == RAILTRACK_NE_SW || GetRailTracks(tile) == RAILTRACK_NW_SE);
    00187   EnforcePrecondition(false, IsRailTypeAvailable(GetCurrentRailType()));
    00188
    00189   return AIObject::DoCommand(tile, GetCurrentRailType() | (GetRailTracks(tile) == RAILTRACK_NE_SW ? AXIS_X : AXIS_Y) << 4 | 1 << 8 | 1 << 16, STAT_CLASS_WAYP | INVALID_STATION << 16, CMD_BUILD_RAIL_WAYPOINT);
    00190 }
    00191
    00192 /* static */ bool AIRail::RemoveRailWaypointTileRectangle(TileIndex tile, TileIndex tile2, bool keep_rail)
    00193 {
    00194   EnforcePrecondition(false, ::IsValidTile(tile));
    00195   EnforcePrecondition(false, ::IsValidTile(tile2));
    00196
    00197   return AIObject::DoCommand(tile, tile2, keep_rail ? 1 : 0, CMD_REMOVE_FROM_RAIL_WAYPOINT);
    00198 }
    00199
    00200 /* static */ bool AIRail::RemoveRailStationTileRectangle(TileIndex tile, TileIndex tile2, bool keep_rail)
    00201 {
    00202   EnforcePrecondition(false, ::IsValidTile(tile));
    00203   EnforcePrecondition(false, ::IsValidTile(tile2));
    00204
    00205   return AIObject::DoCommand(tile, tile2, keep_rail ? 1 : 0, CMD_REMOVE_FROM_RAIL_STATION);
    00206 }
    00207
    00208 /* static */ uint AIRail::GetRailTracks(TileIndex tile)
    00209 {
    00210   if (!IsRailTile(tile)) return RAILTRACK_INVALID;
    00211
    00212   if (IsRailStationTile(tile) || IsRailWaypointTile(tile)) return ::TrackToTrackBits(::GetRailStationTrack(tile));
    00213   if (IsLevelCrossingTile(tile)) return ::GetCrossingRailBits(tile);
    00214   if (IsRailDepotTile(tile)) return ::TRACK_BIT_NONE;
    00215   return ::GetTrackBits(tile);
    00216 }
    00217
    00218 /* static */ bool AIRail::BuildRailTrack(TileIndex tile, RailTrack rail_track)
    00219 {
    00220   EnforcePrecondition(false, ::IsValidTile(tile));
    00221   EnforcePrecondition(false, rail_track != 0);
    00222   EnforcePrecondition(false, (rail_track & ~::TRACK_BIT_ALL) == 0);
    00223   EnforcePrecondition(false, KillFirstBit((uint)rail_track) == 0);
    00224   EnforcePrecondition(false, IsRailTypeAvailable(GetCurrentRailType()));
    00225
    00226   return AIObject::DoCommand(tile, tile, GetCurrentRailType() | (FindFirstTrack((::TrackBits)rail_track) << 4), CMD_BUILD_RAILROAD_TRACK);
    00227 }
    00228
    00229 /* static */ bool AIRail::RemoveRailTrack(TileIndex tile, RailTrack rail_track)
    00230 {
    00231   EnforcePrecondition(false, ::IsValidTile(tile));
    00232   EnforcePrecondition(false, ::IsPlainRailTile(tile) || ::IsLevelCrossingTile(tile));
    00233   EnforcePrecondition(false, GetRailTracks(tile) & rail_track);
    00234   EnforcePrecondition(false, KillFirstBit((uint)rail_track) == 0);
    00235
    00236   return AIObject::DoCommand(tile, tile, GetCurrentRailType() | (FindFirstTrack((::TrackBits)rail_track) << 4), CMD_REMOVE_RAILROAD_TRACK);
    00237 }
    00238
    00239 /* static */ bool AIRail::AreTilesConnected(TileIndex from, TileIndex tile, TileIndex to)
    00240 {
    00241   if (!IsRailTile(tile)) return false;
    00242   if (from == to || AIMap::DistanceManhattan(from, tile) != 1 || AIMap::DistanceManhattan(tile, to) != 1) return false;
    00243
    00244   if (to < from) ::Swap(from, to);
    00245
    00246   if (tile - from == 1) {
    00247     if (to - tile == 1) return (GetRailTracks(tile) & RAILTRACK_NE_SW) != 0;
    00248     if (to - tile == ::MapSizeX()) return (GetRailTracks(tile) & RAILTRACK_NE_SE) != 0;
    00249   } else if (tile - from == ::MapSizeX()) {
    00250     if (tile - to == 1) return (GetRailTracks(tile) & RAILTRACK_NW_NE) != 0;
    00251     if (to - tile == 1) return (GetRailTracks(tile) & RAILTRACK_NW_SW) != 0;
    00252     if (to - tile == ::MapSizeX()) return (GetRailTracks(tile) & RAILTRACK_NW_SE) != 0;
    00253   } else {
    00254     return (GetRailTracks(tile) & RAILTRACK_SW_SE) != 0;
    00255   }
    00256
    00257   NOT_REACHED();
    00258 }
    00259
    00264 static uint32 SimulateDrag(TileIndex from, TileIndex tile, TileIndex *to)
    00265 {
    00266   int diag_offset = abs(abs((int)::TileX(*to) - (int)::TileX(tile)) - abs((int)::TileY(*to) - (int)::TileY(tile)));
    00267   uint32 p2 = AIRail::GetCurrentRailType();
    00268   if (::TileY(from) == ::TileY(*to)) {
    00269     p2 |= (TRACK_X << 4);
    00270     *to -= Clamp((int)::TileX(*to) - (int)::TileX(tile), -1, 1);
    00271   } else if (::TileX(from) == ::TileX(*to)) {
    00272     p2 |= (TRACK_Y << 4);
    00273     *to -= ::MapSizeX() * Clamp((int)::TileY(*to) - (int)::TileY(tile), -1, 1);
    00274   } else if (::TileY(from) < ::TileY(tile)) {
    00275     if (::TileX(*to) < ::TileX(tile)) {
    00276       p2 |= (TRACK_UPPER << 4);
    00277     } else {
    00278       p2 |= (TRACK_LEFT << 4);
    00279     }
    00280     if (diag_offset) {
    00281       *to -= Clamp((int)::TileX(*to) - (int)::TileX(tile), -1, 1);
    00282     } else {
    00283       *to -= ::MapSizeX() * Clamp((int)::TileY(*to) - (int)::TileY(tile), -1, 1);
    00284     }
    00285   } else if (::TileY(from) > ::TileY(tile)) {
    00286     if (::TileX(*to) < ::TileX(tile)) {
    00287       p2 |= (TRACK_RIGHT << 4);
    00288     } else {
    00289       p2 |= (TRACK_LOWER << 4);
    00290     }
    00291     if (diag_offset) {
    00292       *to -= Clamp((int)::TileX(*to) - (int)::TileX(tile), -1, 1);
    00293     } else {
    00294       *to -= ::MapSizeX() * Clamp((int)::TileY(*to) - (int)::TileY(tile), -1, 1);
    00295     }
    00296   } else if (::TileX(from) < ::TileX(tile)) {
    00297     if (::TileY(*to) < ::TileY(tile)) {
    00298       p2 |= (TRACK_UPPER << 4);
    00299     } else {
    00300       p2 |= (TRACK_RIGHT << 4);
    00301     }
    00302     if (!diag_offset) {
    00303       *to -= Clamp((int)::TileX(*to) - (int)::TileX(tile), -1, 1);
    00304     } else {
    00305       *to -= ::MapSizeX() * Clamp((int)::TileY(*to) - (int)::TileY(tile), -1, 1);
    00306     }
    00307   } else if (::TileX(from) > ::TileX(tile)) {
    00308     if (::TileY(*to) < ::TileY(tile)) {
    00309       p2 |= (TRACK_LEFT << 4);
    00310     } else {
    00311       p2 |= (TRACK_LOWER << 4);
    00312     }
    00313     if (!diag_offset) {
    00314       *to -= Clamp((int)::TileX(*to) - (int)::TileX(tile), -1, 1);
    00315     } else {
    00316       *to -= ::MapSizeX() * Clamp((int)::TileY(*to) - (int)::TileY(tile), -1, 1);
    00317     }
    00318   }
    00319   return p2;
    00320 }
    00321
    00322 /* static */ bool AIRail::BuildRail(TileIndex from, TileIndex tile, TileIndex to)
    00323 {
    00324   EnforcePrecondition(false, ::IsValidTile(from));
    00325   EnforcePrecondition(false, ::IsValidTile(tile));
    00326   EnforcePrecondition(false, ::IsValidTile(to));
    00327   EnforcePrecondition(false, ::DistanceManhattan(from, tile) == 1);
    00328   EnforcePrecondition(false, ::DistanceManhattan(tile, to) >= 1);
    00329   EnforcePrecondition(false, IsRailTypeAvailable(GetCurrentRailType()));
    00330   int diag_offset = abs(abs((int)::TileX(to) - (int)::TileX(tile)) - abs((int)::TileY(to) - (int)::TileY(tile)));
    00331   EnforcePrecondition(false, diag_offset <= 1 ||
    00332       (::TileX(from) == ::TileX(tile) && ::TileX(tile) == ::TileX(to)) ||
    00333       (::TileY(from) == ::TileY(tile) && ::TileY(tile) == ::TileY(to)));
    00334
    00335   uint32 p2 = SimulateDrag(from, tile, &to) | 1 << 8;
    00336   return AIObject::DoCommand(tile, to, p2, CMD_BUILD_RAILROAD_TRACK);
    00337 }
    00338
    00339 /* static */ bool AIRail::RemoveRail(TileIndex from, TileIndex tile, TileIndex to)
    00340 {
    00341   EnforcePrecondition(false, ::IsValidTile(from));
    00342   EnforcePrecondition(false, ::IsValidTile(tile));
    00343   EnforcePrecondition(false, ::IsValidTile(to));
    00344   EnforcePrecondition(false, ::DistanceManhattan(from, tile) == 1);
    00345   EnforcePrecondition(false, ::DistanceManhattan(tile, to) >= 1);
    00346   int diag_offset = abs(abs((int)::TileX(to) - (int)::TileX(tile)) - abs((int)::TileY(to) - (int)::TileY(tile)));
    00347   EnforcePrecondition(false, diag_offset <= 1 ||
    00348       (::TileX(from) == ::TileX(tile) && ::TileX(tile) == ::TileX(to)) ||
    00349       (::TileY(from) == ::TileY(tile) && ::TileY(tile) == ::TileY(to)));
    00350
    00351   if (!IsRailTypeAvailable(GetCurrentRailType())) SetCurrentRailType(GetRailType(tile));
    00352   uint32 p2 = SimulateDrag(from, tile, &to);
    00353   return AIObject::DoCommand(tile, to, p2, CMD_REMOVE_RAILROAD_TRACK);
    00354 }
    00355
    00360 struct AIRailSignalData {
    00361   Track track;
    00362   Trackdir trackdir;
    00363   uint signal_cycles;
    00364 };
    00365
    00366 static const int NUM_TRACK_DIRECTIONS = 3;
    00367
    00374 static const AIRailSignalData _possible_trackdirs[5][NUM_TRACK_DIRECTIONS] = {
    00375   {{TRACK_UPPER,   TRACKDIR_UPPER_E, 0}, {TRACK_Y,       TRACKDIR_Y_SE,    0}, {TRACK_LEFT,    TRACKDIR_LEFT_S,  1}},
    00376   {{TRACK_RIGHT,   TRACKDIR_RIGHT_S, 1}, {TRACK_X,       TRACKDIR_X_SW,    1}, {TRACK_UPPER,   TRACKDIR_UPPER_W, 1}},
    00377   {{INVALID_TRACK, INVALID_TRACKDIR, 0}, {INVALID_TRACK, INVALID_TRACKDIR, 0}, {INVALID_TRACK, INVALID_TRACKDIR, 0}},
    00378   {{TRACK_LOWER,   TRACKDIR_LOWER_E, 0}, {TRACK_X,       TRACKDIR_X_NE,    0}, {TRACK_LEFT,    TRACKDIR_LEFT_N,  0}},
    00379   {{TRACK_RIGHT,   TRACKDIR_RIGHT_N, 0}, {TRACK_Y,       TRACKDIR_Y_NW,    1}, {TRACK_LOWER,   TRACKDIR_LOWER_W, 1}}
    00380 };
    00381
    00382 /* static */ AIRail::SignalType AIRail::GetSignalType(TileIndex tile, TileIndex front)
    00383 {
    00384   if (AIMap::DistanceManhattan(tile, front) != 1) return SIGNALTYPE_NONE;
    00385   if (!::IsTileType(tile, MP_RAILWAY) || !::HasSignals(tile)) return SIGNALTYPE_NONE;
    00386
    00387   int data_index = 2 + (::TileX(front) - ::TileX(tile)) + 2 * (::TileY(front) - ::TileY(tile));
    00388
    00389   for (int i = 0; i < NUM_TRACK_DIRECTIONS; i++) {
    00390     const Track &track = _possible_trackdirs[data_index][i].track;
    00391     if (!(::TrackToTrackBits(track) & GetRailTracks(tile))) continue;
    00392     if (!HasSignalOnTrack(tile, track)) continue;
    00393     if (!HasSignalOnTrackdir(tile, _possible_trackdirs[data_index][i].trackdir)) continue;
    00394     SignalType st = (SignalType)::GetSignalType(tile, track);
    00395     if (HasSignalOnTrackdir(tile, ::ReverseTrackdir(_possible_trackdirs[data_index][i].trackdir))) st = (SignalType)(st | SIGNALTYPE_TWOWAY);
    00396     return st;
    00397   }
    00398
    00399   return SIGNALTYPE_NONE;
    00400 }
    00401
    00405 static bool IsValidSignalType(int signal_type)
    00406 {
    00407   if (signal_type < AIRail::SIGNALTYPE_NORMAL || signal_type > AIRail::SIGNALTYPE_COMBO_TWOWAY) return false;
    00408   if (signal_type > AIRail::SIGNALTYPE_PBS_ONEWAY && signal_type < AIRail::SIGNALTYPE_NORMAL_TWOWAY) return false;
    00409   return true;
    00410 }
    00411
    00412 /* static */ bool AIRail::BuildSignal(TileIndex tile, TileIndex front, SignalType signal)
    00413 {
    00414   EnforcePrecondition(false, AIMap::DistanceManhattan(tile, front) == 1)
    00415   EnforcePrecondition(false, ::IsPlainRailTile(tile));
    00416   EnforcePrecondition(false, ::IsValidSignalType(signal));
    00417
    00418   Track track = INVALID_TRACK;
    00419   uint signal_cycles;
    00420
    00421   int data_index = 2 + (::TileX(front) - ::TileX(tile)) + 2 * (::TileY(front) - ::TileY(tile));
    00422   for (int i = 0; i < NUM_TRACK_DIRECTIONS; i++) {
    00423     const Track &t = _possible_trackdirs[data_index][i].track;
    00424     if (!(::TrackToTrackBits(t) & GetRailTracks(tile))) continue;
    00425     track = t;
    00426     signal_cycles = _possible_trackdirs[data_index][i].signal_cycles;
    00427     break;
    00428   }
    00429   EnforcePrecondition(false, track != INVALID_TRACK);
    00430
    00431   uint p1 = track;
    00432   if (signal < SIGNALTYPE_TWOWAY) {
    00433     if (signal != SIGNALTYPE_PBS && signal != SIGNALTYPE_PBS_ONEWAY) signal_cycles++;
    00434     p1 |= (signal_cycles << 15);
    00435   }
    00436   p1 |= ((signal >= SIGNALTYPE_TWOWAY ? signal ^ SIGNALTYPE_TWOWAY : signal) << 5);
    00437
    00438   return AIObject::DoCommand(tile, p1, 0, CMD_BUILD_SIGNALS);
    00439 }
    00440
    00441 /* static */ bool AIRail::RemoveSignal(TileIndex tile, TileIndex front)
    00442 {
    00443   EnforcePrecondition(false, AIMap::DistanceManhattan(tile, front) == 1)
    00444   EnforcePrecondition(false, GetSignalType(tile, front) != SIGNALTYPE_NONE);
    00445
    00446   Track track = INVALID_TRACK;
    00447   int data_index = 2 + (::TileX(front) - ::TileX(tile)) + 2 * (::TileY(front) - ::TileY(tile));
    00448   for (int i = 0; i < NUM_TRACK_DIRECTIONS; i++) {
    00449     const Track &t = _possible_trackdirs[data_index][i].track;
    00450     if (!(::TrackToTrackBits(t) & GetRailTracks(tile))) continue;
    00451     track = t;
    00452     break;
    00453   }
    00454   EnforcePrecondition(false, track != INVALID_TRACK);
    00455
    00456   return AIObject::DoCommand(tile, track, 0, CMD_REMOVE_SIGNALS);
    00457 }
    00458
    00459 /* static */ Money AIRail::GetBuildCost(RailType railtype, BuildType build_type)
    00460 {
    00461   if (!AIRail::IsRailTypeAvailable(railtype)) return -1;
    00462
    00463   switch (build_type) {
    00464     case BT_TRACK:    return ::RailBuildCost((::RailType)railtype);
    00465     case BT_SIGNAL:   return ::GetPrice(PR_BUILD_SIGNALS, 1, NULL);
    00466     case BT_DEPOT:    return ::GetPrice(PR_BUILD_DEPOT_TRAIN, 1, NULL);
    00467     case BT_STATION:  return ::GetPrice(PR_BUILD_STATION_RAIL, 1, NULL) + ::GetPrice(PR_BUILD_STATION_RAIL_LENGTH, 1, NULL);
    00468     case BT_WAYPOINT: return ::GetPrice(PR_BUILD_WAYPOINT_RAIL, 1, NULL);
    00469     default: return -1;
    00470   }
    00471 }