src/script/api/script_rail.cpp

   1 /*
   2  * This file is part of OpenTTD.
   3  * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
   4  * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
   5  * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
   6  */
   7
   8 /** @file script_rail.cpp Implementation of ScriptRail. */
   9
  10 #include "../../stdafx.h"
  11 #include "script_rail.hpp"
  12 #include "script_map.hpp"
  13 #include "script_station.hpp"
  14 #include "script_industrytype.hpp"
  15 #include "script_cargo.hpp"
  16 #include "../../debug.h"
  17 #include "../../station_base.h"
  18 #include "../../newgrf_generic.h"
  19 #include "../../newgrf_station.h"
  20 #include "../../strings_func.h"
  21 #include "../../rail_cmd.h"
  22 #include "../../station_cmd.h"
  23 #include "../../waypoint_cmd.h"
  24
  25 #include "../../safeguards.h"
  26
  27 /* static */ std::optional<std::string> ScriptRail::GetName(RailType rail_type)
  28 {
  29         if (!IsRailTypeAvailable(rail_type)) return std::nullopt;
  30
  31         return GetString(GetRailTypeInfo((::RailType)rail_type)->strings.menu_text);
  32 }
  33
  34 /* static */ bool ScriptRail::IsRailTile(TileIndex tile)
  35 {
  36         if (!::IsValidTile(tile)) return false;
  37
  38         return (::IsTileType(tile, MP_RAILWAY) && !::IsRailDepot(tile)) ||
  39                         (::HasStationTileRail(tile) && !::IsStationTileBlocked(tile)) || ::IsLevelCrossingTile(tile);
  40 }
  41
  42 /* static */ bool ScriptRail::IsLevelCrossingTile(TileIndex tile)
  43 {
  44         if (!::IsValidTile(tile)) return false;
  45
  46         return ::IsLevelCrossingTile(tile);
  47 }
  48
  49 /* static */ bool ScriptRail::IsRailDepotTile(TileIndex tile)
  50 {
  51         if (!::IsValidTile(tile)) return false;
  52
  53         return ::IsRailDepotTile(tile);
  54 }
  55
  56 /* static */ bool ScriptRail::IsRailStationTile(TileIndex tile)
  57 {
  58         if (!::IsValidTile(tile)) return false;
  59
  60         return ::IsRailStationTile(tile);
  61 }
  62
  63 /* static */ bool ScriptRail::IsRailWaypointTile(TileIndex tile)
  64 {
  65         if (!::IsValidTile(tile)) return false;
  66
  67         return ::IsRailWaypointTile(tile);
  68 }
  69
  70 /* static */ bool ScriptRail::IsRailTypeAvailable(RailType rail_type)
  71 {
  72         EnforceDeityOrCompanyModeValid(false);
  73         if ((::RailType)rail_type >= RAILTYPE_END) return false;
  74
  75         return ScriptCompanyMode::IsDeity() || ::HasRailTypeAvail(ScriptObject::GetCompany(), (::RailType)rail_type);
  76 }
  77
  78 /* static */ ScriptRail::RailType ScriptRail::GetCurrentRailType()
  79 {
  80         return (RailType)ScriptObject::GetRailType();
  81 }
  82
  83 /* static */ void ScriptRail::SetCurrentRailType(RailType rail_type)
  84 {
  85         if (!IsRailTypeAvailable(rail_type)) return;
  86
  87         ScriptObject::SetRailType((::RailType)rail_type);
  88 }
  89
  90 /* static */ bool ScriptRail::TrainCanRunOnRail(ScriptRail::RailType engine_rail_type, ScriptRail::RailType track_rail_type)
  91 {
  92         if (!ScriptRail::IsRailTypeAvailable(engine_rail_type)) return false;
  93         if (!ScriptRail::IsRailTypeAvailable(track_rail_type)) return false;
  94
  95         return ::IsCompatibleRail((::RailType)engine_rail_type, (::RailType)track_rail_type);
  96 }
  97
  98 /* static */ bool ScriptRail::TrainHasPowerOnRail(ScriptRail::RailType engine_rail_type, ScriptRail::RailType track_rail_type)
  99 {\
 100         if (!ScriptRail::IsRailTypeAvailable(engine_rail_type)) return false;
 101         if (!ScriptRail::IsRailTypeAvailable(track_rail_type)) return false;
 102
 103         return ::HasPowerOnRail((::RailType)engine_rail_type, (::RailType)track_rail_type);
 104 }
 105
 106 /* static */ ScriptRail::RailType ScriptRail::GetRailType(TileIndex tile)
 107 {
 108         if (!ScriptTile::HasTransportType(tile, ScriptTile::TRANSPORT_RAIL)) return RAILTYPE_INVALID;
 109
 110         return (RailType)::GetRailType(tile);
 111 }
 112
 113 /* static */ bool ScriptRail::ConvertRailType(TileIndex start_tile, TileIndex end_tile, ScriptRail::RailType convert_to)
 114 {
 115         EnforceCompanyModeValid(false);
 116         EnforcePrecondition(false, ::IsValidTile(start_tile));
 117         EnforcePrecondition(false, ::IsValidTile(end_tile));
 118         EnforcePrecondition(false, IsRailTypeAvailable(convert_to));
 119
 120         return ScriptObject::Command<CMD_CONVERT_RAIL>::Do(start_tile, end_tile, (::RailType)convert_to, false);
 121 }
 122
 123 /* static */ TileIndex ScriptRail::GetRailDepotFrontTile(TileIndex depot)
 124 {
 125         if (!IsRailDepotTile(depot)) return INVALID_TILE;
 126
 127         return depot + ::TileOffsByDiagDir(::GetRailDepotDirection(depot));
 128 }
 129
 130 /* static */ ScriptRail::RailTrack ScriptRail::GetRailStationDirection(TileIndex tile)
 131 {
 132         if (!IsRailStationTile(tile)) return RAILTRACK_INVALID;
 133
 134         return (RailTrack)::GetRailStationTrackBits(tile);
 135 }
 136
 137 /* static */ bool ScriptRail::BuildRailDepot(TileIndex tile, TileIndex front)
 138 {
 139         EnforceCompanyModeValid(false);
 140         EnforcePrecondition(false, tile != front);
 141         EnforcePrecondition(false, ::IsValidTile(tile));
 142         EnforcePrecondition(false, ::IsValidTile(front));
 143         EnforcePrecondition(false, ::TileX(tile) == ::TileX(front) || ::TileY(tile) == ::TileY(front));
 144         EnforcePrecondition(false, IsRailTypeAvailable(GetCurrentRailType()));
 145
 146         DiagDirection entrance_dir = (::TileX(tile) == ::TileX(front)) ? (::TileY(tile) < ::TileY(front) ? DIAGDIR_SE : DIAGDIR_NW) : (::TileX(tile) < ::TileX(front) ? DIAGDIR_SW : DIAGDIR_NE);
 147
 148         return ScriptObject::Command<CMD_BUILD_TRAIN_DEPOT>::Do(tile, (::RailType)ScriptObject::GetRailType(), entrance_dir);
 149 }
 150
 151 /* static */ bool ScriptRail::BuildRailStation(TileIndex tile, RailTrack direction, SQInteger num_platforms, SQInteger platform_length, StationID station_id)
 152 {
 153         EnforceCompanyModeValid(false);
 154         EnforcePrecondition(false, ::IsValidTile(tile));
 155         EnforcePrecondition(false, direction == RAILTRACK_NW_SE || direction == RAILTRACK_NE_SW);
 156         EnforcePrecondition(false, num_platforms > 0 && num_platforms <= 0xFF);
 157         EnforcePrecondition(false, platform_length > 0 && platform_length <= 0xFF);
 158         EnforcePrecondition(false, IsRailTypeAvailable(GetCurrentRailType()));
 159         EnforcePrecondition(false, station_id == ScriptStation::STATION_NEW || station_id == ScriptStation::STATION_JOIN_ADJACENT || ScriptStation::IsValidStation(station_id));
 160
 161         bool adjacent = station_id != ScriptStation::STATION_JOIN_ADJACENT;
 162         return ScriptObject::Command<CMD_BUILD_RAIL_STATION>::Do(tile, (::RailType)GetCurrentRailType(), direction == RAILTRACK_NW_SE ? AXIS_Y : AXIS_X, num_platforms, platform_length, STAT_CLASS_DFLT, 0, ScriptStation::IsValidStation(station_id) ? station_id : INVALID_STATION, adjacent);
 163 }
 164
 165 /* static */ bool ScriptRail::BuildNewGRFRailStation(TileIndex tile, RailTrack direction, SQInteger num_platforms, SQInteger platform_length, StationID station_id, CargoID cargo_id, IndustryType source_industry, IndustryType goal_industry, SQInteger distance, bool source_station)
 166 {
 167         EnforceCompanyModeValid(false);
 168         EnforcePrecondition(false, ::IsValidTile(tile));
 169         EnforcePrecondition(false, direction == RAILTRACK_NW_SE || direction == RAILTRACK_NE_SW);
 170         EnforcePrecondition(false, num_platforms > 0 && num_platforms <= 0xFF);
 171         EnforcePrecondition(false, platform_length > 0 && platform_length <= 0xFF);
 172         EnforcePrecondition(false, IsRailTypeAvailable(GetCurrentRailType()));
 173         EnforcePrecondition(false, station_id == ScriptStation::STATION_NEW || station_id == ScriptStation::STATION_JOIN_ADJACENT || ScriptStation::IsValidStation(station_id));
 174         EnforcePrecondition(false, ScriptCargo::IsValidCargo(cargo_id));
 175         EnforcePrecondition(false, source_industry == ScriptIndustryType::INDUSTRYTYPE_UNKNOWN || source_industry == ScriptIndustryType::INDUSTRYTYPE_TOWN || ScriptIndustryType::IsValidIndustryType(source_industry));
 176         EnforcePrecondition(false, goal_industry   == ScriptIndustryType::INDUSTRYTYPE_UNKNOWN || goal_industry   == ScriptIndustryType::INDUSTRYTYPE_TOWN || ScriptIndustryType::IsValidIndustryType(goal_industry));
 177
 178         const GRFFile *file;
 179         uint16_t res = GetAiPurchaseCallbackResult(
 180                 GSF_STATIONS,
 181                 cargo_id,
 182                 0,
 183                 source_industry,
 184                 goal_industry,
 185                 ClampTo<uint8_t>(distance / 2),
 186                 AICE_STATION_GET_STATION_ID,
 187                 source_station ? 0 : 1,
 188                 std::min<SQInteger>(15u, num_platforms) << 4 | std::min<SQInteger>(15u, platform_length),
 189                 &file
 190         );
 191
 192         Axis axis = direction == RAILTRACK_NW_SE ? AXIS_Y : AXIS_X;
 193         bool adjacent = station_id != ScriptStation::STATION_JOIN_ADJACENT;
 194         StationID to_join = ScriptStation::IsValidStation(station_id) ? station_id : INVALID_STATION;
 195         if (res != CALLBACK_FAILED) {
 196                 const StationSpec *spec = StationClass::GetByGrf(file->grfid, res);
 197                 if (spec == nullptr) {
 198                         Debug(grf, 1, "{} returned an invalid station ID for 'AI construction/purchase selection (18)' callback", file->filename);
 199                 } else {
 200                         /* We might have gotten an usable station spec. Try to build it, but if it fails we'll fall back to the original station. */
 201                         if (ScriptObject::Command<CMD_BUILD_RAIL_STATION>::Do(tile, (::RailType)GetCurrentRailType(), axis, num_platforms, platform_length, spec->class_index, spec->index, to_join, adjacent)) return true;
 202                 }
 203         }
 204
 205         return ScriptObject::Command<CMD_BUILD_RAIL_STATION>::Do(tile, (::RailType)GetCurrentRailType(), axis, num_platforms, platform_length, STAT_CLASS_DFLT, 0, to_join, adjacent);
 206 }
 207
 208 /* static */ bool ScriptRail::BuildRailWaypoint(TileIndex tile)
 209 {
 210         EnforceCompanyModeValid(false);
 211         EnforcePrecondition(false, ::IsValidTile(tile));
 212         EnforcePrecondition(false, IsRailTile(tile));
 213         EnforcePrecondition(false, GetRailTracks(tile) == RAILTRACK_NE_SW || GetRailTracks(tile) == RAILTRACK_NW_SE);
 214         EnforcePrecondition(false, IsRailTypeAvailable(GetCurrentRailType()));
 215
 216         return ScriptObject::Command<CMD_BUILD_RAIL_WAYPOINT>::Do(tile, GetRailTracks(tile) == RAILTRACK_NE_SW ? AXIS_X : AXIS_Y, 1, 1, STAT_CLASS_WAYP, 0, INVALID_STATION, false);
 217 }
 218
 219 /* static */ bool ScriptRail::RemoveRailWaypointTileRectangle(TileIndex tile, TileIndex tile2, bool keep_rail)
 220 {
 221         EnforceCompanyModeValid(false);
 222         EnforcePrecondition(false, ::IsValidTile(tile));
 223         EnforcePrecondition(false, ::IsValidTile(tile2));
 224
 225         return ScriptObject::Command<CMD_REMOVE_FROM_RAIL_WAYPOINT>::Do(tile, tile2, keep_rail);
 226 }
 227
 228 /* static */ bool ScriptRail::RemoveRailStationTileRectangle(TileIndex tile, TileIndex tile2, bool keep_rail)
 229 {
 230         EnforceCompanyModeValid(false);
 231         EnforcePrecondition(false, ::IsValidTile(tile));
 232         EnforcePrecondition(false, ::IsValidTile(tile2));
 233
 234         return ScriptObject::Command<CMD_REMOVE_FROM_RAIL_STATION>::Do(tile, tile2, keep_rail);
 235 }
 236
 237 /* static */ uint ScriptRail::GetRailTracks(TileIndex tile)
 238 {
 239         if (!IsRailTile(tile)) return RAILTRACK_INVALID;
 240
 241         if (IsRailStationTile(tile) || IsRailWaypointTile(tile)) return ::TrackToTrackBits(::GetRailStationTrack(tile));
 242         if (IsLevelCrossingTile(tile)) return ::GetCrossingRailBits(tile);
 243         if (IsRailDepotTile(tile)) return ::TRACK_BIT_NONE;
 244         return ::GetTrackBits(tile);
 245 }
 246
 247 /* static */ bool ScriptRail::BuildRailTrack(TileIndex tile, RailTrack rail_track)
 248 {
 249         EnforceCompanyModeValid(false);
 250         EnforcePrecondition(false, ::IsValidTile(tile));
 251         EnforcePrecondition(false, rail_track != 0);
 252         EnforcePrecondition(false, (static_cast<uint>(rail_track) & ~static_cast<uint>(::TRACK_BIT_ALL)) == 0);
 253         EnforcePrecondition(false, KillFirstBit((uint)rail_track) == 0);
 254         EnforcePrecondition(false, IsRailTypeAvailable(GetCurrentRailType()));
 255
 256         return ScriptObject::Command<CMD_BUILD_RAILROAD_TRACK>::Do(tile, tile, (::RailType)GetCurrentRailType(), FindFirstTrack((::TrackBits)rail_track), false, false);
 257 }
 258
 259 /* static */ bool ScriptRail::RemoveRailTrack(TileIndex tile, RailTrack rail_track)
 260 {
 261         EnforceCompanyModeValid(false);
 262         EnforcePrecondition(false, ::IsValidTile(tile));
 263         EnforcePrecondition(false, ::IsPlainRailTile(tile) || ::IsLevelCrossingTile(tile));
 264         EnforcePrecondition(false, GetRailTracks(tile) & rail_track);
 265         EnforcePrecondition(false, KillFirstBit((uint)rail_track) == 0);
 266
 267         return ScriptObject::Command<CMD_REMOVE_RAILROAD_TRACK>::Do(tile, tile, FindFirstTrack((::TrackBits)rail_track));
 268 }
 269
 270 /* static */ bool ScriptRail::AreTilesConnected(TileIndex from, TileIndex tile, TileIndex to)
 271 {
 272         if (!IsRailTile(tile)) return false;
 273         if (from == to || ScriptMap::DistanceManhattan(from, tile) != 1 || ScriptMap::DistanceManhattan(tile, to) != 1) return false;
 274
 275         if (to < from) ::Swap(from, to);
 276
 277         if (tile - from == 1) {
 278                 if (to - tile == 1) return (GetRailTracks(tile) & RAILTRACK_NE_SW) != 0;
 279                 if (to - tile == (int)ScriptMap::GetMapSizeX()) return (GetRailTracks(tile) & RAILTRACK_NE_SE) != 0;
 280         } else if (tile - from == (int)ScriptMap::GetMapSizeX()) {
 281                 if (tile - to == 1) return (GetRailTracks(tile) & RAILTRACK_NW_NE) != 0;
 282                 if (to - tile == 1) return (GetRailTracks(tile) & RAILTRACK_NW_SW) != 0;
 283                 if (to - tile == (int)ScriptMap::GetMapSizeX()) return (GetRailTracks(tile) & RAILTRACK_NW_SE) != 0;
 284         } else {
 285                 return (GetRailTracks(tile) & RAILTRACK_SW_SE) != 0;
 286         }
 287
 288         NOT_REACHED();
 289 }
 290
 291 /**
 292  * Prepare the second parameter for CmdBuildRailroadTrack and CmdRemoveRailroadTrack. The direction
 293  * depends on all three tiles. Sometimes the third tile needs to be adjusted.
 294  */
 295 static Track SimulateDrag(TileIndex from, TileIndex tile, TileIndex *to)
 296 {
 297         int diag_offset = abs(abs((int)::TileX(*to) - (int)::TileX(tile)) - abs((int)::TileY(*to) - (int)::TileY(tile)));
 298         Track track = TRACK_BEGIN;
 299         if (::TileY(from) == ::TileY(*to)) {
 300                 track = TRACK_X;
 301                 *to -= Clamp((int)::TileX(*to) - (int)::TileX(tile), -1, 1);
 302         } else if (::TileX(from) == ::TileX(*to)) {
 303                 track = TRACK_Y;
 304                 *to -= ScriptMap::GetMapSizeX() * Clamp((int)::TileY(*to) - (int)::TileY(tile), -1, 1);
 305         } else if (::TileY(from) < ::TileY(tile)) {
 306                 if (::TileX(*to) < ::TileX(tile)) {
 307                         track = TRACK_UPPER;
 308                 } else {
 309                         track = TRACK_LEFT;
 310                 }
 311                 if (diag_offset != 0) {
 312                         *to -= Clamp((int)::TileX(*to) - (int)::TileX(tile), -1, 1);
 313                 } else {
 314                         *to -= ScriptMap::GetMapSizeX() * Clamp((int)::TileY(*to) - (int)::TileY(tile), -1, 1);
 315                 }
 316         } else if (::TileY(from) > ::TileY(tile)) {
 317                 if (::TileX(*to) < ::TileX(tile)) {
 318                         track = TRACK_RIGHT;
 319                 } else {
 320                         track = TRACK_LOWER;
 321                 }
 322                 if (diag_offset != 0) {
 323                         *to -= Clamp((int)::TileX(*to) - (int)::TileX(tile), -1, 1);
 324                 } else {
 325                         *to -= ScriptMap::GetMapSizeX() * Clamp((int)::TileY(*to) - (int)::TileY(tile), -1, 1);
 326                 }
 327         } else if (::TileX(from) < ::TileX(tile)) {
 328                 if (::TileY(*to) < ::TileY(tile)) {
 329                         track = TRACK_UPPER;
 330                 } else {
 331                         track = TRACK_RIGHT;
 332                 }
 333                 if (diag_offset == 0) {
 334                         *to -= Clamp((int)::TileX(*to) - (int)::TileX(tile), -1, 1);
 335                 } else {
 336                         *to -= ScriptMap::GetMapSizeX() * Clamp((int)::TileY(*to) - (int)::TileY(tile), -1, 1);
 337                 }
 338         } else if (::TileX(from) > ::TileX(tile)) {
 339                 if (::TileY(*to) < ::TileY(tile)) {
 340                         track = TRACK_LEFT;
 341                 } else {
 342                         track = TRACK_LOWER;
 343                 }
 344                 if (diag_offset == 0) {
 345                         *to -= Clamp((int)::TileX(*to) - (int)::TileX(tile), -1, 1);
 346                 } else {
 347                         *to -= ScriptMap::GetMapSizeX() * Clamp((int)::TileY(*to) - (int)::TileY(tile), -1, 1);
 348                 }
 349         }
 350         return track;
 351 }
 352
 353 /* static */ bool ScriptRail::BuildRail(TileIndex from, TileIndex tile, TileIndex to)
 354 {
 355         EnforceCompanyModeValid(false);
 356         EnforcePrecondition(false, ::IsValidTile(from));
 357         EnforcePrecondition(false, ::IsValidTile(tile));
 358         EnforcePrecondition(false, ::IsValidTile(to));
 359         EnforcePrecondition(false, ::DistanceManhattan(from, tile) == 1);
 360         EnforcePrecondition(false, ::DistanceManhattan(tile, to) >= 1);
 361         EnforcePrecondition(false, IsRailTypeAvailable(GetCurrentRailType()));
 362         int diag_offset = abs(abs((int)::TileX(to) - (int)::TileX(tile)) - abs((int)::TileY(to) - (int)::TileY(tile)));
 363         EnforcePrecondition(false, diag_offset <= 1 ||
 364                         (::TileX(from) == ::TileX(tile) && ::TileX(tile) == ::TileX(to)) ||
 365                         (::TileY(from) == ::TileY(tile) && ::TileY(tile) == ::TileY(to)));
 366
 367         Track track = SimulateDrag(from, tile, &to);
 368         return ScriptObject::Command<CMD_BUILD_RAILROAD_TRACK>::Do(to, tile, (::RailType)ScriptRail::GetCurrentRailType(), track, false, true);
 369 }
 370
 371 /* static */ bool ScriptRail::RemoveRail(TileIndex from, TileIndex tile, TileIndex to)
 372 {
 373         EnforceCompanyModeValid(false);
 374         EnforcePrecondition(false, ::IsValidTile(from));
 375         EnforcePrecondition(false, ::IsValidTile(tile));
 376         EnforcePrecondition(false, ::IsValidTile(to));
 377         EnforcePrecondition(false, ::DistanceManhattan(from, tile) == 1);
 378         EnforcePrecondition(false, ::DistanceManhattan(tile, to) >= 1);
 379         int diag_offset = abs(abs((int)::TileX(to) - (int)::TileX(tile)) - abs((int)::TileY(to) - (int)::TileY(tile)));
 380         EnforcePrecondition(false, diag_offset <= 1 ||
 381                         (::TileX(from) == ::TileX(tile) && ::TileX(tile) == ::TileX(to)) ||
 382                         (::TileY(from) == ::TileY(tile) && ::TileY(tile) == ::TileY(to)));
 383
 384         Track track = SimulateDrag(from, tile, &to);
 385         return ScriptObject::Command<CMD_REMOVE_RAILROAD_TRACK>::Do(to, tile, track);
 386 }
 387
 388 /**
 389  * Contains information about the trackdir that belongs to a track when entering
 390  *   from a specific direction.
 391  */
 392 struct ScriptRailSignalData {
 393         Track track;        ///< The track that will be taken to travel.
 394         Trackdir trackdir;  ///< The Trackdir belonging to that track.
 395         uint signal_cycles; ///< How many times the signal should be cycled in order to build it in the correct direction.
 396 };
 397
 398 static const int NUM_TRACK_DIRECTIONS = 3; ///< The number of directions you can go when entering a tile.
 399
 400 /**
 401  * List information about the trackdir and number of needed cycles for building signals when
 402  *   entering a track from a specific direction. The first index is the difference between the
 403  *   TileIndex of the previous and current tile, where (-)MapSizeX is replaced with -2 / 2 and
 404  *   2 it added.
 405  */
 406 static const ScriptRailSignalData _possible_trackdirs[5][NUM_TRACK_DIRECTIONS] = {
 407         {{TRACK_UPPER,   TRACKDIR_UPPER_E, 0}, {TRACK_Y,       TRACKDIR_Y_SE,    0}, {TRACK_LEFT,    TRACKDIR_LEFT_S,  1}},
 408         {{TRACK_RIGHT,   TRACKDIR_RIGHT_S, 1}, {TRACK_X,       TRACKDIR_X_SW,    1}, {TRACK_UPPER,   TRACKDIR_UPPER_W, 1}},
 409         {{INVALID_TRACK, INVALID_TRACKDIR, 0}, {INVALID_TRACK, INVALID_TRACKDIR, 0}, {INVALID_TRACK, INVALID_TRACKDIR, 0}},
 410         {{TRACK_LOWER,   TRACKDIR_LOWER_E, 0}, {TRACK_X,       TRACKDIR_X_NE,    0}, {TRACK_LEFT,    TRACKDIR_LEFT_N,  0}},
 411         {{TRACK_RIGHT,   TRACKDIR_RIGHT_N, 0}, {TRACK_Y,       TRACKDIR_Y_NW,    1}, {TRACK_LOWER,   TRACKDIR_LOWER_W, 1}}
 412 };
 413
 414 /* static */ ScriptRail::SignalType ScriptRail::GetSignalType(TileIndex tile, TileIndex front)
 415 {
 416         if (ScriptMap::DistanceManhattan(tile, front) != 1) return SIGNALTYPE_NONE;
 417         if (!::IsTileType(tile, MP_RAILWAY) || !::HasSignals(tile)) return SIGNALTYPE_NONE;
 418
 419         int data_index = 2 + (::TileX(front) - ::TileX(tile)) + 2 * (::TileY(front) - ::TileY(tile));
 420
 421         for (int i = 0; i < NUM_TRACK_DIRECTIONS; i++) {
 422                 const Track &track = _possible_trackdirs[data_index][i].track;
 423                 if (!(::TrackToTrackBits(track) & GetRailTracks(tile))) continue;
 424                 if (!HasSignalOnTrack(tile, track)) continue;
 425                 if (!HasSignalOnTrackdir(tile, _possible_trackdirs[data_index][i].trackdir)) continue;
 426                 SignalType st = (SignalType)::GetSignalType(tile, track);
 427                 if (HasSignalOnTrackdir(tile, ::ReverseTrackdir(_possible_trackdirs[data_index][i].trackdir))) st = (SignalType)(st | SIGNALTYPE_TWOWAY);
 428                 return st;
 429         }
 430
 431         return SIGNALTYPE_NONE;
 432 }
 433
 434 /**
 435  * Check if signal_type is a valid SignalType.
 436  */
 437 static bool IsValidSignalType(int signal_type)
 438 {
 439         if (signal_type < ScriptRail::SIGNALTYPE_NORMAL || signal_type > ScriptRail::SIGNALTYPE_COMBO_TWOWAY) return false;
 440         if (signal_type > ScriptRail::SIGNALTYPE_PBS_ONEWAY && signal_type < ScriptRail::SIGNALTYPE_NORMAL_TWOWAY) return false;
 441         return true;
 442 }
 443
 444 /* static */ bool ScriptRail::BuildSignal(TileIndex tile, TileIndex front, SignalType signal)
 445 {
 446         EnforceCompanyModeValid(false);
 447         EnforcePrecondition(false, ScriptMap::DistanceManhattan(tile, front) == 1)
 448         EnforcePrecondition(false, ::IsPlainRailTile(tile));
 449         EnforcePrecondition(false, ::IsValidSignalType(signal));
 450
 451         Track track = INVALID_TRACK;
 452         uint signal_cycles = 0;
 453
 454         int data_index = 2 + (::TileX(front) - ::TileX(tile)) + 2 * (::TileY(front) - ::TileY(tile));
 455         for (int i = 0; i < NUM_TRACK_DIRECTIONS; i++) {
 456                 const Track &t = _possible_trackdirs[data_index][i].track;
 457                 if (!(::TrackToTrackBits(t) & GetRailTracks(tile))) continue;
 458                 track = t;
 459                 signal_cycles = _possible_trackdirs[data_index][i].signal_cycles;
 460                 break;
 461         }
 462         EnforcePrecondition(false, track != INVALID_TRACK);
 463
 464         if (signal < SIGNALTYPE_TWOWAY) {
 465                 if (signal != SIGNALTYPE_PBS && signal != SIGNALTYPE_PBS_ONEWAY) signal_cycles++;
 466         } else {
 467                 signal_cycles = 0;
 468         }
 469         ::SignalType sig_type = (::SignalType)(signal >= SIGNALTYPE_TWOWAY ? signal ^ SIGNALTYPE_TWOWAY : signal);
 470
 471         return ScriptObject::Command<CMD_BUILD_SINGLE_SIGNAL>::Do(tile, track, sig_type, ::SIG_ELECTRIC, false, false, false, ::SIGTYPE_BLOCK, ::SIGTYPE_BLOCK, signal_cycles, 0);
 472 }
 473
 474 /* static */ bool ScriptRail::RemoveSignal(TileIndex tile, TileIndex front)
 475 {
 476         EnforceCompanyModeValid(false);
 477         EnforcePrecondition(false, ScriptMap::DistanceManhattan(tile, front) == 1)
 478         EnforcePrecondition(false, GetSignalType(tile, front) != SIGNALTYPE_NONE);
 479
 480         Track track = INVALID_TRACK;
 481         int data_index = 2 + (::TileX(front) - ::TileX(tile)) + 2 * (::TileY(front) - ::TileY(tile));
 482         for (int i = 0; i < NUM_TRACK_DIRECTIONS; i++) {
 483                 const Track &t = _possible_trackdirs[data_index][i].track;
 484                 if (!(::TrackToTrackBits(t) & GetRailTracks(tile))) continue;
 485                 track = t;
 486                 break;
 487         }
 488         EnforcePrecondition(false, track != INVALID_TRACK);
 489
 490         return ScriptObject::Command<CMD_REMOVE_SINGLE_SIGNAL>::Do(tile, track);
 491 }
 492
 493 /* static */ Money ScriptRail::GetBuildCost(RailType railtype, BuildType build_type)
 494 {
 495         if (!ScriptRail::IsRailTypeAvailable(railtype)) return -1;
 496
 497         switch (build_type) {
 498                 case BT_TRACK:    return ::RailBuildCost((::RailType)railtype);
 499                 case BT_SIGNAL:   return ::GetPrice(PR_BUILD_SIGNALS, 1, nullptr);
 500                 case BT_DEPOT:    return ::GetPrice(PR_BUILD_DEPOT_TRAIN, 1, nullptr);
 501                 case BT_STATION:  return ::GetPrice(PR_BUILD_STATION_RAIL, 1, nullptr) + ::GetPrice(PR_BUILD_STATION_RAIL_LENGTH, 1, nullptr);
 502                 case BT_WAYPOINT: return ::GetPrice(PR_BUILD_WAYPOINT_RAIL, 1, nullptr);
 503                 default: return -1;
 504         }
 505 }
 506
 507 /* static */ SQInteger ScriptRail::GetMaxSpeed(RailType railtype)
 508 {
 509         if (!ScriptRail::IsRailTypeAvailable(railtype)) return -1;
 510
 511         return ::GetRailTypeInfo((::RailType)railtype)->max_speed;
 512 }
 513
 514 /* static */ SQInteger ScriptRail::GetMaintenanceCostFactor(RailType railtype)
 515 {
 516         if (!ScriptRail::IsRailTypeAvailable(railtype)) return 0;
 517
 518         return ::GetRailTypeInfo((::RailType)railtype)->maintenance_multiplier;
 519 }