# train_cmd.cpp

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    00001 /* $Id: train_cmd.cpp 26130 2013-11-26 16:08:58Z rubidium $ */
    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 "error.h"
    00014 #include "articulated_vehicles.h"
    00015 #include "command_func.h"
    00016 #include "pathfinder/npf/npf_func.h"
    00017 #include "pathfinder/yapf/yapf.hpp"
    00018 #include "news_func.h"
    00019 #include "company_func.h"
    00020 #include "newgrf_sound.h"
    00021 #include "newgrf_text.h"
    00022 #include "strings_func.h"
    00023 #include "viewport_func.h"
    00024 #include "vehicle_func.h"
    00025 #include "sound_func.h"
    00026 #include "ai/ai.hpp"
    00027 #include "game/game.hpp"
    00028 #include "newgrf_station.h"
    00029 #include "effectvehicle_func.h"
    00030 #include "network/network.h"
    00031 #include "spritecache.h"
    00032 #include "core/random_func.hpp"
    00033 #include "company_base.h"
    00034 #include "newgrf.h"
    00035 #include "order_backup.h"
    00036 #include "zoom_func.h"
    00037 #include "newgrf_debug.h"
    00038
    00039 #include "table/strings.h"
    00040 #include "table/train_cmd.h"
    00041
    00042 static Track ChooseTrainTrack(Train *v, TileIndex tile, DiagDirection enterdir, TrackBits tracks, bool force_res, bool *got_reservation, bool mark_stuck);
    00043 static bool TrainCheckIfLineEnds(Train *v, bool reverse = true);
    00044 bool TrainController(Train *v, Vehicle *nomove, bool reverse = true); // Also used in vehicle_sl.cpp.
    00045 static TileIndex TrainApproachingCrossingTile(const Train *v);
    00046 static void CheckIfTrainNeedsService(Train *v);
    00047 static void CheckNextTrainTile(Train *v);
    00048
    00049 static const byte _vehicle_initial_x_fract[4] = {10, 8, 4,  8};
    00050 static const byte _vehicle_initial_y_fract[4] = { 8, 4, 8, 10};
    00051
    00052 template <>
    00053 bool IsValidImageIndex<VEH_TRAIN>(uint8 image_index)
    00054 {
    00055   return image_index < lengthof(_engine_sprite_base);
    00056 }
    00057
    00065 static inline DiagDirection TrainExitDir(Direction direction, TrackBits track)
    00066 {
    00067   static const TrackBits state_dir_table[DIAGDIR_END] = { TRACK_BIT_RIGHT, TRACK_BIT_LOWER, TRACK_BIT_LEFT, TRACK_BIT_UPPER };
    00068
    00069   DiagDirection diagdir = DirToDiagDir(direction);
    00070
    00071   /* Determine the diagonal direction in which we will exit this tile */
    00072   if (!HasBit(direction, 0) && track != state_dir_table[diagdir]) {
    00073     diagdir = ChangeDiagDir(diagdir, DIAGDIRDIFF_90LEFT);
    00074   }
    00075
    00076   return diagdir;
    00077 }
    00078
    00079
    00085 byte FreightWagonMult(CargoID cargo)
    00086 {
    00087   if (!CargoSpec::Get(cargo)->is_freight) return 1;
    00088   return _settings_game.vehicle.freight_trains;
    00089 }
    00090
    00092 void CheckTrainsLengths()
    00093 {
    00094   const Train *v;
    00095   bool first = true;
    00096
    00097   FOR_ALL_TRAINS(v) {
    00098     if (v->First() == v && !(v->vehstatus & VS_CRASHED)) {
    00099       for (const Train *u = v, *w = v->Next(); w != NULL; u = w, w = w->Next()) {
    00100         if (u->track != TRACK_BIT_DEPOT) {
    00101           if ((w->track != TRACK_BIT_DEPOT &&
    00102               max(abs(u->x_pos - w->x_pos), abs(u->y_pos - w->y_pos)) != u->CalcNextVehicleOffset()) ||
    00103               (w->track == TRACK_BIT_DEPOT && TicksToLeaveDepot(u) <= 0)) {
    00104             SetDParam(0, v->index);
    00105             SetDParam(1, v->owner);
    00106             ShowErrorMessage(STR_BROKEN_VEHICLE_LENGTH, INVALID_STRING_ID, WL_CRITICAL);
    00107
    00108             if (!_networking && first) {
    00109               first = false;
    00110               DoCommandP(0, PM_PAUSED_ERROR, 1, CMD_PAUSE);
    00111             }
    00112             /* Break so we warn only once for each train. */
    00113             break;
    00114           }
    00115         }
    00116       }
    00117     }
    00118   }
    00119 }
    00120
    00127 void Train::ConsistChanged(bool same_length)
    00128 {
    00129   uint16 max_speed = UINT16_MAX;
    00130
    00131   assert(this->IsFrontEngine() || this->IsFreeWagon());
    00132
    00133   const RailVehicleInfo *rvi_v = RailVehInfo(this->engine_type);
    00134   EngineID first_engine = this->IsFrontEngine() ? this->engine_type : INVALID_ENGINE;
    00135   this->gcache.cached_total_length = 0;
    00136   this->compatible_railtypes = RAILTYPES_NONE;
    00137
    00138   bool train_can_tilt = true;
    00139
    00140   for (Train *u = this; u != NULL; u = u->Next()) {
    00141     const RailVehicleInfo *rvi_u = RailVehInfo(u->engine_type);
    00142
    00143     /* Check the this->first cache. */
    00144     assert(u->First() == this);
    00145
    00146     /* update the 'first engine' */
    00147     u->gcache.first_engine = this == u ? INVALID_ENGINE : first_engine;
    00148     u->railtype = rvi_u->railtype;
    00149
    00150     if (u->IsEngine()) first_engine = u->engine_type;
    00151
    00152     /* Set user defined data to its default value */
    00153     u->tcache.user_def_data = rvi_u->user_def_data;
    00154     this->InvalidateNewGRFCache();
    00155     u->InvalidateNewGRFCache();
    00156   }
    00157
    00158   for (Train *u = this; u != NULL; u = u->Next()) {
    00159     /* Update user defined data (must be done before other properties) */
    00160     u->tcache.user_def_data = GetVehicleProperty(u, PROP_TRAIN_USER_DATA, u->tcache.user_def_data);
    00161     this->InvalidateNewGRFCache();
    00162     u->InvalidateNewGRFCache();
    00163   }
    00164
    00165   for (Train *u = this; u != NULL; u = u->Next()) {
    00166     const Engine *e_u = u->GetEngine();
    00167     const RailVehicleInfo *rvi_u = &e_u->u.rail;
    00168
    00169     if (!HasBit(e_u->info.misc_flags, EF_RAIL_TILTS)) train_can_tilt = false;
    00170
    00171     /* Cache wagon override sprite group. NULL is returned if there is none */
    00172     u->tcache.cached_override = GetWagonOverrideSpriteSet(u->engine_type, u->cargo_type, u->gcache.first_engine);
    00173
    00174     /* Reset colour map */
    00175     u->colourmap = PAL_NONE;
    00176
    00177     /* Update powered-wagon-status and visual effect */
    00178     u->UpdateVisualEffect(true);
    00179
    00180     if (rvi_v->pow_wag_power != 0 && rvi_u->railveh_type == RAILVEH_WAGON &&
    00181         UsesWagonOverride(u) && !HasBit(u->vcache.cached_vis_effect, VE_DISABLE_WAGON_POWER)) {
    00182       /* wagon is powered */
    00183       SetBit(u->flags, VRF_POWEREDWAGON); // cache 'powered' status
    00184     } else {
    00185       ClrBit(u->flags, VRF_POWEREDWAGON);
    00186     }
    00187
    00188     if (!u->IsArticulatedPart()) {
    00189       /* Do not count powered wagons for the compatible railtypes, as wagons always
    00190          have railtype normal */
    00191       if (rvi_u->power > 0) {
    00192         this->compatible_railtypes |= GetRailTypeInfo(u->railtype)->powered_railtypes;
    00193       }
    00194
    00195       /* Some electric engines can be allowed to run on normal rail. It happens to all
    00196        * existing electric engines when elrails are disabled and then re-enabled */
    00197       if (HasBit(u->flags, VRF_EL_ENGINE_ALLOWED_NORMAL_RAIL)) {
    00198         u->railtype = RAILTYPE_RAIL;
    00199         u->compatible_railtypes |= RAILTYPES_RAIL;
    00200       }
    00201
    00202       /* max speed is the minimum of the speed limits of all vehicles in the consist */
    00203       if ((rvi_u->railveh_type != RAILVEH_WAGON || _settings_game.vehicle.wagon_speed_limits) && !UsesWagonOverride(u)) {
    00204         uint16 speed = GetVehicleProperty(u, PROP_TRAIN_SPEED, rvi_u->max_speed);
    00205         if (speed != 0) max_speed = min(speed, max_speed);
    00206       }
    00207     }
    00208
    00209     uint16 new_cap = e_u->DetermineCapacity(u);
    00210     u->refit_cap = min(new_cap, u->refit_cap);
    00211     u->cargo_cap = new_cap;
    00212     u->vcache.cached_cargo_age_period = GetVehicleProperty(u, PROP_TRAIN_CARGO_AGE_PERIOD, e_u->info.cargo_age_period);
    00213
    00214     /* check the vehicle length (callback) */
    00215     uint16 veh_len = CALLBACK_FAILED;
    00216     if (e_u->GetGRF() != NULL && e_u->GetGRF()->grf_version >= 8) {
    00217       /* Use callback 36 */
    00218       veh_len = GetVehicleProperty(u, PROP_TRAIN_SHORTEN_FACTOR, CALLBACK_FAILED);
    00219
    00220       if (veh_len != CALLBACK_FAILED && veh_len >= VEHICLE_LENGTH) {
    00221         ErrorUnknownCallbackResult(e_u->GetGRFID(), CBID_VEHICLE_LENGTH, veh_len);
    00222       }
    00223     } else if (HasBit(e_u->info.callback_mask, CBM_VEHICLE_LENGTH)) {
    00224       /* Use callback 11 */
    00225       veh_len = GetVehicleCallback(CBID_VEHICLE_LENGTH, 0, 0, u->engine_type, u);
    00226     }
    00227     if (veh_len == CALLBACK_FAILED) veh_len = rvi_u->shorten_factor;
    00228     veh_len = VEHICLE_LENGTH - Clamp(veh_len, 0, VEHICLE_LENGTH - 1);
    00229
    00230     /* verify length hasn't changed */
    00231     if (same_length && veh_len != u->gcache.cached_veh_length) VehicleLengthChanged(u);
    00232
    00233     /* update vehicle length? */
    00234     if (!same_length) u->gcache.cached_veh_length = veh_len;
    00235
    00236     this->gcache.cached_total_length += u->gcache.cached_veh_length;
    00237     this->InvalidateNewGRFCache();
    00238     u->InvalidateNewGRFCache();
    00239   }
    00240
    00241   /* store consist weight/max speed in cache */
    00242   this->vcache.cached_max_speed = max_speed;
    00243   this->tcache.cached_tilt = train_can_tilt;
    00244   this->tcache.cached_max_curve_speed = this->GetCurveSpeedLimit();
    00245
    00246   /* recalculate cached weights and power too (we do this *after* the rest, so it is known which wagons are powered and need extra weight added) */
    00247   this->CargoChanged();
    00248
    00249   if (this->IsFrontEngine()) {
    00250     this->UpdateAcceleration();
    00251     SetWindowDirty(WC_VEHICLE_DETAILS, this->index);
    00252     InvalidateWindowData(WC_VEHICLE_REFIT, this->index, VIWD_CONSIST_CHANGED);
    00253     InvalidateWindowData(WC_VEHICLE_ORDERS, this->index, VIWD_CONSIST_CHANGED);
    00254     InvalidateNewGRFInspectWindow(GSF_TRAINS, this->index);
    00255   }
    00256 }
    00257
    00268 int GetTrainStopLocation(StationID station_id, TileIndex tile, const Train *v, int *station_ahead, int *station_length)
    00269 {
    00270   const Station *st = Station::Get(station_id);
    00271   *station_ahead  = st->GetPlatformLength(tile, DirToDiagDir(v->direction)) * TILE_SIZE;
    00272   *station_length = st->GetPlatformLength(tile) * TILE_SIZE;
    00273
    00274   /* Default to the middle of the station for stations stops that are not in
    00275    * the order list like intermediate stations when non-stop is disabled */
    00276   OrderStopLocation osl = OSL_PLATFORM_MIDDLE;
    00277   if (v->gcache.cached_total_length >= *station_length) {
    00278     /* The train is longer than the station, make it stop at the far end of the platform */
    00279     osl = OSL_PLATFORM_FAR_END;
    00280   } else if (v->current_order.IsType(OT_GOTO_STATION) && v->current_order.GetDestination() == station_id) {
    00281     osl = v->current_order.GetStopLocation();
    00282   }
    00283
    00284   /* The stop location of the FRONT! of the train */
    00285   int stop;
    00286   switch (osl) {
    00287     default: NOT_REACHED();
    00288
    00289     case OSL_PLATFORM_NEAR_END:
    00290       stop = v->gcache.cached_total_length;
    00291       break;
    00292
    00293     case OSL_PLATFORM_MIDDLE:
    00294       stop = *station_length - (*station_length - v->gcache.cached_total_length) / 2;
    00295       break;
    00296
    00297     case OSL_PLATFORM_FAR_END:
    00298       stop = *station_length;
    00299       break;
    00300   }
    00301
    00302   /* Subtract half the front vehicle length of the train so we get the real
    00303    * stop location of the train. */
    00304   return stop - (v->gcache.cached_veh_length + 1) / 2;
    00305 }
    00306
    00307
    00312 int Train::GetCurveSpeedLimit() const
    00313 {
    00314   assert(this->First() == this);
    00315
    00316   static const int absolute_max_speed = UINT16_MAX;
    00317   int max_speed = absolute_max_speed;
    00318
    00319   if (_settings_game.vehicle.train_acceleration_model == AM_ORIGINAL) return max_speed;
    00320
    00321   int curvecount[2] = {0, 0};
    00322
    00323   /* first find the curve speed limit */
    00324   int numcurve = 0;
    00325   int sum = 0;
    00326   int pos = 0;
    00327   int lastpos = -1;
    00328   for (const Vehicle *u = this; u->Next() != NULL; u = u->Next(), pos++) {
    00329     Direction this_dir = u->direction;
    00330     Direction next_dir = u->Next()->direction;
    00331
    00332     DirDiff dirdiff = DirDifference(this_dir, next_dir);
    00333     if (dirdiff == DIRDIFF_SAME) continue;
    00334
    00335     if (dirdiff == DIRDIFF_45LEFT) curvecount[0]++;
    00336     if (dirdiff == DIRDIFF_45RIGHT) curvecount[1]++;
    00337     if (dirdiff == DIRDIFF_45LEFT || dirdiff == DIRDIFF_45RIGHT) {
    00338       if (lastpos != -1) {
    00339         numcurve++;
    00340         sum += pos - lastpos;
    00341         if (pos - lastpos == 1 && max_speed > 88) {
    00342           max_speed = 88;
    00343         }
    00344       }
    00345       lastpos = pos;
    00346     }
    00347
    00348     /* if we have a 90 degree turn, fix the speed limit to 60 */
    00349     if (dirdiff == DIRDIFF_90LEFT || dirdiff == DIRDIFF_90RIGHT) {
    00350       max_speed = 61;
    00351     }
    00352   }
    00353
    00354   if (numcurve > 0 && max_speed > 88) {
    00355     if (curvecount[0] == 1 && curvecount[1] == 1) {
    00356       max_speed = absolute_max_speed;
    00357     } else {
    00358       sum /= numcurve;
    00359       max_speed = 232 - (13 - Clamp(sum, 1, 12)) * (13 - Clamp(sum, 1, 12));
    00360     }
    00361   }
    00362
    00363   if (max_speed != absolute_max_speed) {
    00364     /* Apply the engine's rail type curve speed advantage, if it slowed by curves */
    00365     const RailtypeInfo *rti = GetRailTypeInfo(this->railtype);
    00366     max_speed += (max_speed / 2) * rti->curve_speed;
    00367
    00368     if (this->tcache.cached_tilt) {
    00369       /* Apply max_speed bonus of 20% for a tilting train */
    00370       max_speed += max_speed / 5;
    00371     }
    00372   }
    00373
    00374   return max_speed;
    00375 }
    00376
    00381 int Train::GetCurrentMaxSpeed() const
    00382 {
    00383   int max_speed = _settings_game.vehicle.train_acceleration_model == AM_ORIGINAL ?
    00384       this->gcache.cached_max_track_speed :
    00385       this->tcache.cached_max_curve_speed;
    00386
    00387   if (_settings_game.vehicle.train_acceleration_model == AM_REALISTIC && IsRailStationTile(this->tile)) {
    00388     StationID sid = GetStationIndex(this->tile);
    00389     if (this->current_order.ShouldStopAtStation(this, sid)) {
    00390       int station_ahead;
    00391       int station_length;
    00392       int stop_at = GetTrainStopLocation(sid, this->tile, this, &station_ahead, &station_length);
    00393
    00394       /* The distance to go is whatever is still ahead of the train minus the
    00395        * distance from the train's stop location to the end of the platform */
    00396       int distance_to_go = station_ahead / TILE_SIZE - (station_length - stop_at) / TILE_SIZE;
    00397
    00398       if (distance_to_go > 0) {
    00399         int st_max_speed = 120;
    00400
    00401         int delta_v = this->cur_speed / (distance_to_go + 1);
    00402         if (max_speed > (this->cur_speed - delta_v)) {
    00403           st_max_speed = this->cur_speed - (delta_v / 10);
    00404         }
    00405
    00406         st_max_speed = max(st_max_speed, 25 * distance_to_go);
    00407         max_speed = min(max_speed, st_max_speed);
    00408       }
    00409     }
    00410   }
    00411
    00412   for (const Train *u = this; u != NULL; u = u->Next()) {
    00413     if (_settings_game.vehicle.train_acceleration_model == AM_REALISTIC && u->track == TRACK_BIT_DEPOT) {
    00414       max_speed = min(max_speed, 61);
    00415       break;
    00416     }
    00417
    00418     /* Vehicle is on the middle part of a bridge. */
    00419     if (u->track == TRACK_BIT_WORMHOLE && !(u->vehstatus & VS_HIDDEN)) {
    00420       max_speed = min(max_speed, GetBridgeSpec(GetBridgeType(u->tile))->speed);
    00421     }
    00422   }
    00423
    00424   max_speed = min(max_speed, this->current_order.max_speed);
    00425   return min(max_speed, this->gcache.cached_max_track_speed);
    00426 }
    00427
    00429 void Train::UpdateAcceleration()
    00430 {
    00431   assert(this->IsFrontEngine() || this->IsFreeWagon());
    00432
    00433   uint power = this->gcache.cached_power;
    00434   uint weight = this->gcache.cached_weight;
    00435   assert(weight != 0);
    00436   this->acceleration = Clamp(power / weight * 4, 1, 255);
    00437 }
    00438
    00444 int Train::GetDisplayImageWidth(Point *offset) const
    00445 {
    00446   int reference_width = TRAININFO_DEFAULT_VEHICLE_WIDTH;
    00447   int vehicle_pitch = 0;
    00448
    00449   const Engine *e = this->GetEngine();
    00450   if (e->GetGRF() != NULL && is_custom_sprite(e->u.rail.image_index)) {
    00451     reference_width = e->GetGRF()->traininfo_vehicle_width;
    00452     vehicle_pitch = e->GetGRF()->traininfo_vehicle_pitch;
    00453   }
    00454
    00455   if (offset != NULL) {
    00456     offset->x = reference_width / 2;
    00457     offset->y = vehicle_pitch;
    00458   }
    00459   return this->gcache.cached_veh_length * reference_width / VEHICLE_LENGTH;
    00460 }
    00461
    00462 static SpriteID GetDefaultTrainSprite(uint8 spritenum, Direction direction)
    00463 {
    00464   assert(IsValidImageIndex<VEH_TRAIN>(spritenum));
    00465   return ((direction + _engine_sprite_add[spritenum]) & _engine_sprite_and[spritenum]) + _engine_sprite_base[spritenum];
    00466 }
    00467
    00474 SpriteID Train::GetImage(Direction direction, EngineImageType image_type) const
    00475 {
    00476   uint8 spritenum = this->spritenum;
    00477   SpriteID sprite;
    00478
    00479   if (HasBit(this->flags, VRF_REVERSE_DIRECTION)) direction = ReverseDir(direction);
    00480
    00481   if (is_custom_sprite(spritenum)) {
    00482     sprite = GetCustomVehicleSprite(this, (Direction)(direction + 4 * IS_CUSTOM_SECONDHEAD_SPRITE(spritenum)), image_type);
    00483     if (sprite != 0) return sprite;
    00484
    00485     spritenum = this->GetEngine()->original_image_index;
    00486   }
    00487
    00488   assert(IsValidImageIndex<VEH_TRAIN>(spritenum));
    00489   sprite = GetDefaultTrainSprite(spritenum, direction);
    00490
    00491   if (this->cargo.StoredCount() >= this->cargo_cap / 2U) sprite += _wagon_full_adder[spritenum];
    00492
    00493   return sprite;
    00494 }
    00495
    00496 static SpriteID GetRailIcon(EngineID engine, bool rear_head, int &y, EngineImageType image_type)
    00497 {
    00498   const Engine *e = Engine::Get(engine);
    00499   Direction dir = rear_head ? DIR_E : DIR_W;
    00500   uint8 spritenum = e->u.rail.image_index;
    00501
    00502   if (is_custom_sprite(spritenum)) {
    00503     SpriteID sprite = GetCustomVehicleIcon(engine, dir, image_type);
    00504     if (sprite != 0) {
    00505       if (e->GetGRF() != NULL) {
    00506         y += e->GetGRF()->traininfo_vehicle_pitch;
    00507       }
    00508       return sprite;
    00509     }
    00510
    00511     spritenum = Engine::Get(engine)->original_image_index;
    00512   }
    00513
    00514   if (rear_head) spritenum++;
    00515
    00516   return GetDefaultTrainSprite(spritenum, DIR_W);
    00517 }
    00518
    00519 void DrawTrainEngine(int left, int right, int preferred_x, int y, EngineID engine, PaletteID pal, EngineImageType image_type)
    00520 {
    00521   if (RailVehInfo(engine)->railveh_type == RAILVEH_MULTIHEAD) {
    00522     int yf = y;
    00523     int yr = y;
    00524
    00525     SpriteID spritef = GetRailIcon(engine, false, yf, image_type);
    00526     SpriteID spriter = GetRailIcon(engine, true, yr, image_type);
    00527     const Sprite *real_spritef = GetSprite(spritef, ST_NORMAL);
    00528     const Sprite *real_spriter = GetSprite(spriter, ST_NORMAL);
    00529
    00530     preferred_x = Clamp(preferred_x, left - UnScaleByZoom(real_spritef->x_offs, ZOOM_LVL_GUI) + 14, right - UnScaleByZoom(real_spriter->width, ZOOM_LVL_GUI) - UnScaleByZoom(real_spriter->x_offs, ZOOM_LVL_GUI) - 15);
    00531
    00532     DrawSprite(spritef, pal, preferred_x - 14, yf);
    00533     DrawSprite(spriter, pal, preferred_x + 15, yr);
    00534   } else {
    00535     SpriteID sprite = GetRailIcon(engine, false, y, image_type);
    00536     const Sprite *real_sprite = GetSprite(sprite, ST_NORMAL);
    00537     preferred_x = Clamp(preferred_x, left - UnScaleByZoom(real_sprite->x_offs, ZOOM_LVL_GUI), right - UnScaleByZoom(real_sprite->width, ZOOM_LVL_GUI) - UnScaleByZoom(real_sprite->x_offs, ZOOM_LVL_GUI));
    00538     DrawSprite(sprite, pal, preferred_x, y);
    00539   }
    00540 }
    00541
    00551 void GetTrainSpriteSize(EngineID engine, uint &width, uint &height, int &xoffs, int &yoffs, EngineImageType image_type)
    00552 {
    00553   int y = 0;
    00554
    00555   SpriteID sprite = GetRailIcon(engine, false, y, image_type);
    00556   const Sprite *real_sprite = GetSprite(sprite, ST_NORMAL);
    00557
    00558   width  = UnScaleByZoom(real_sprite->width, ZOOM_LVL_GUI);
    00559   height = UnScaleByZoom(real_sprite->height, ZOOM_LVL_GUI);
    00560   xoffs  = UnScaleByZoom(real_sprite->x_offs, ZOOM_LVL_GUI);
    00561   yoffs  = UnScaleByZoom(real_sprite->y_offs, ZOOM_LVL_GUI);
    00562
    00563   if (RailVehInfo(engine)->railveh_type == RAILVEH_MULTIHEAD) {
    00564     sprite = GetRailIcon(engine, true, y, image_type);
    00565     real_sprite = GetSprite(sprite, ST_NORMAL);
    00566
    00567     /* Calculate values relative to an imaginary center between the two sprites. */
    00568     width = TRAININFO_DEFAULT_VEHICLE_WIDTH + UnScaleByZoom(real_sprite->width, ZOOM_LVL_GUI) + UnScaleByZoom(real_sprite->x_offs, ZOOM_LVL_GUI) - xoffs;
    00569     height = max<uint>(height, UnScaleByZoom(real_sprite->height, ZOOM_LVL_GUI));
    00570     xoffs  = xoffs - TRAININFO_DEFAULT_VEHICLE_WIDTH / 2;
    00571     yoffs  = min(yoffs, UnScaleByZoom(real_sprite->y_offs, ZOOM_LVL_GUI));
    00572   }
    00573 }
    00574
    00583 static CommandCost CmdBuildRailWagon(TileIndex tile, DoCommandFlag flags, const Engine *e, Vehicle **ret)
    00584 {
    00585   const RailVehicleInfo *rvi = &e->u.rail;
    00586
    00587   /* Check that the wagon can drive on the track in question */
    00588   if (!IsCompatibleRail(rvi->railtype, GetRailType(tile))) return CMD_ERROR;
    00589
    00590   if (flags & DC_EXEC) {
    00591     Train *v = new Train();
    00592     *ret = v;
    00593     v->spritenum = rvi->image_index;
    00594
    00595     v->engine_type = e->index;
    00596     v->gcache.first_engine = INVALID_ENGINE; // needs to be set before first callback
    00597
    00598     DiagDirection dir = GetRailDepotDirection(tile);
    00599
    00600     v->direction = DiagDirToDir(dir);
    00601     v->tile = tile;
    00602
    00603     int x = TileX(tile) * TILE_SIZE | _vehicle_initial_x_fract[dir];
    00604     int y = TileY(tile) * TILE_SIZE | _vehicle_initial_y_fract[dir];
    00605
    00606     v->x_pos = x;
    00607     v->y_pos = y;
    00608     v->z_pos = GetSlopePixelZ(x, y);
    00609     v->owner = _current_company;
    00610     v->track = TRACK_BIT_DEPOT;
    00611     v->vehstatus = VS_HIDDEN | VS_DEFPAL;
    00612
    00613     v->SetWagon();
    00614
    00615     v->SetFreeWagon();
    00616     InvalidateWindowData(WC_VEHICLE_DEPOT, v->tile);
    00617
    00618     v->cargo_type = e->GetDefaultCargoType();
    00619     v->cargo_cap = rvi->capacity;
    00620     v->refit_cap = 0;
    00621
    00622     v->railtype = rvi->railtype;
    00623
    00624     v->build_year = _cur_year;
    00625     v->cur_image = SPR_IMG_QUERY;
    00626     v->random_bits = VehicleRandomBits();
    00627
    00628     v->group_id = DEFAULT_GROUP;
    00629
    00630     AddArticulatedParts(v);
    00631
    00632     _new_vehicle_id = v->index;
    00633
    00634     VehicleUpdatePosition(v);
    00635     v->First()->ConsistChanged(false);
    00636     UpdateTrainGroupID(v->First());
    00637
    00638     CheckConsistencyOfArticulatedVehicle(v);
    00639
    00640     /* Try to connect the vehicle to one of free chains of wagons. */
    00641     Train *w;
    00642     FOR_ALL_TRAINS(w) {
    00643       if (w->tile == tile &&
    00644           w->IsFreeWagon() &&
    00645           w->engine_type == e->index &&
    00646           w->First() != v &&
    00647           !(w->vehstatus & VS_CRASHED)) {
    00648         DoCommand(0, v->index | 1 << 20, w->Last()->index, DC_EXEC, CMD_MOVE_RAIL_VEHICLE);
    00649         break;
    00650       }
    00651     }
    00652   }
    00653
    00654   return CommandCost();
    00655 }
    00656
    00658 static void NormalizeTrainVehInDepot(const Train *u)
    00659 {
    00660   const Train *v;
    00661   FOR_ALL_TRAINS(v) {
    00662     if (v->IsFreeWagon() && v->tile == u->tile &&
    00663         v->track == TRACK_BIT_DEPOT) {
    00664       if (DoCommand(0, v->index | 1 << 20, u->index, DC_EXEC,
    00665           CMD_MOVE_RAIL_VEHICLE).Failed())
    00666         break;
    00667     }
    00668   }
    00669 }
    00670
    00671 static void AddRearEngineToMultiheadedTrain(Train *v)
    00672 {
    00673   Train *u = new Train();
    00674   v->value >>= 1;
    00675   u->value = v->value;
    00676   u->direction = v->direction;
    00677   u->owner = v->owner;
    00678   u->tile = v->tile;
    00679   u->x_pos = v->x_pos;
    00680   u->y_pos = v->y_pos;
    00681   u->z_pos = v->z_pos;
    00682   u->track = TRACK_BIT_DEPOT;
    00683   u->vehstatus = v->vehstatus & ~VS_STOPPED;
    00684   u->spritenum = v->spritenum + 1;
    00685   u->cargo_type = v->cargo_type;
    00686   u->cargo_subtype = v->cargo_subtype;
    00687   u->cargo_cap = v->cargo_cap;
    00688   u->refit_cap = v->refit_cap;
    00689   u->railtype = v->railtype;
    00690   u->engine_type = v->engine_type;
    00691   u->build_year = v->build_year;
    00692   u->cur_image = SPR_IMG_QUERY;
    00693   u->random_bits = VehicleRandomBits();
    00694   v->SetMultiheaded();
    00695   u->SetMultiheaded();
    00696   v->SetNext(u);
    00697   VehicleUpdatePosition(u);
    00698
    00699   /* Now we need to link the front and rear engines together */
    00700   v->other_multiheaded_part = u;
    00701   u->other_multiheaded_part = v;
    00702 }
    00703
    00713 CommandCost CmdBuildRailVehicle(TileIndex tile, DoCommandFlag flags, const Engine *e, uint16 data, Vehicle **ret)
    00714 {
    00715   const RailVehicleInfo *rvi = &e->u.rail;
    00716
    00717   if (rvi->railveh_type == RAILVEH_WAGON) return CmdBuildRailWagon(tile, flags, e, ret);
    00718
    00719   /* Check if depot and new engine uses the same kind of tracks *
    00720    * We need to see if the engine got power on the tile to avoid electric engines in non-electric depots */
    00721   if (!HasPowerOnRail(rvi->railtype, GetRailType(tile))) return CMD_ERROR;
    00722
    00723   if (flags & DC_EXEC) {
    00724     DiagDirection dir = GetRailDepotDirection(tile);
    00725     int x = TileX(tile) * TILE_SIZE + _vehicle_initial_x_fract[dir];
    00726     int y = TileY(tile) * TILE_SIZE + _vehicle_initial_y_fract[dir];
    00727
    00728     Train *v = new Train();
    00729     *ret = v;
    00730     v->direction = DiagDirToDir(dir);
    00731     v->tile = tile;
    00732     v->owner = _current_company;
    00733     v->x_pos = x;
    00734     v->y_pos = y;
    00735     v->z_pos = GetSlopePixelZ(x, y);
    00736     v->track = TRACK_BIT_DEPOT;
    00737     v->vehstatus = VS_HIDDEN | VS_STOPPED | VS_DEFPAL;
    00738     v->spritenum = rvi->image_index;
    00739     v->cargo_type = e->GetDefaultCargoType();
    00740     v->cargo_cap = rvi->capacity;
    00741     v->refit_cap = 0;
    00742     v->last_station_visited = INVALID_STATION;
    00743     v->last_loading_station = INVALID_STATION;
    00744
    00745     v->engine_type = e->index;
    00746     v->gcache.first_engine = INVALID_ENGINE; // needs to be set before first callback
    00747
    00748     v->reliability = e->reliability;
    00749     v->reliability_spd_dec = e->reliability_spd_dec;
    00750     v->max_age = e->GetLifeLengthInDays();
    00751
    00752     v->railtype = rvi->railtype;
    00753     _new_vehicle_id = v->index;
    00754
    00755     v->SetServiceInterval(Company::Get(_current_company)->settings.vehicle.servint_trains);
    00756     v->date_of_last_service = _date;
    00757     v->build_year = _cur_year;
    00758     v->cur_image = SPR_IMG_QUERY;
    00759     v->random_bits = VehicleRandomBits();
    00760
    00761     if (e->flags & ENGINE_EXCLUSIVE_PREVIEW) SetBit(v->vehicle_flags, VF_BUILT_AS_PROTOTYPE);
    00762     v->SetServiceIntervalIsPercent(Company::Get(_current_company)->settings.vehicle.servint_ispercent);
    00763
    00764     v->group_id = DEFAULT_GROUP;
    00765
    00766     v->SetFrontEngine();
    00767     v->SetEngine();
    00768
    00769     VehicleUpdatePosition(v);
    00770
    00771     if (rvi->railveh_type == RAILVEH_MULTIHEAD) {
    00772       AddRearEngineToMultiheadedTrain(v);
    00773     } else {
    00774       AddArticulatedParts(v);
    00775     }
    00776
    00777     v->ConsistChanged(false);
    00778     UpdateTrainGroupID(v);
    00779
    00780     if (!HasBit(data, 0) && !(flags & DC_AUTOREPLACE)) { // check if the cars should be added to the new vehicle
    00781       NormalizeTrainVehInDepot(v);
    00782     }
    00783
    00784     CheckConsistencyOfArticulatedVehicle(v);
    00785   }
    00786
    00787   return CommandCost();
    00788 }
    00789
    00790 static Train *FindGoodVehiclePos(const Train *src)
    00791 {
    00792   EngineID eng = src->engine_type;
    00793   TileIndex tile = src->tile;
    00794
    00795   Train *dst;
    00796   FOR_ALL_TRAINS(dst) {
    00797     if (dst->IsFreeWagon() && dst->tile == tile && !(dst->vehstatus & VS_CRASHED)) {
    00798       /* check so all vehicles in the line have the same engine. */
    00799       Train *t = dst;
    00800       while (t->engine_type == eng) {
    00801         t = t->Next();
    00802         if (t == NULL) return dst;
    00803       }
    00804     }
    00805   }
    00806
    00807   return NULL;
    00808 }
    00809
    00811 typedef SmallVector<Train *, 16> TrainList;
    00812
    00818 static void MakeTrainBackup(TrainList &list, Train *t)
    00819 {
    00820   for (; t != NULL; t = t->Next()) *list.Append() = t;
    00821 }
    00822
    00827 static void RestoreTrainBackup(TrainList &list)
    00828 {
    00829   /* No train, nothing to do. */
    00830   if (list.Length() == 0) return;
    00831
    00832   Train *prev = NULL;
    00833   /* Iterate over the list and rebuild it. */
    00834   for (Train **iter = list.Begin(); iter != list.End(); iter++) {
    00835     Train *t = *iter;
    00836     if (prev != NULL) {
    00837       prev->SetNext(t);
    00838     } else if (t->Previous() != NULL) {
    00839       /* Make sure the head of the train is always the first in the chain. */
    00840       t->Previous()->SetNext(NULL);
    00841     }
    00842     prev = t;
    00843   }
    00844 }
    00845
    00851 static void RemoveFromConsist(Train *part, bool chain = false)
    00852 {
    00853   Train *tail = chain ? part->Last() : part->GetLastEnginePart();
    00854
    00855   /* Unlink at the front, but make it point to the next
    00856    * vehicle after the to be remove part. */
    00857   if (part->Previous() != NULL) part->Previous()->SetNext(tail->Next());
    00858
    00859   /* Unlink at the back */
    00860   tail->SetNext(NULL);
    00861 }
    00862
    00868 static void InsertInConsist(Train *dst, Train *chain)
    00869 {
    00870   /* We do not want to add something in the middle of an articulated part. */
    00871   assert(dst->Next() == NULL || !dst->Next()->IsArticulatedPart());
    00872
    00873   chain->Last()->SetNext(dst->Next());
    00874   dst->SetNext(chain);
    00875 }
    00876
    00882 static void NormaliseDualHeads(Train *t)
    00883 {
    00884   for (; t != NULL; t = t->GetNextVehicle()) {
    00885     if (!t->IsMultiheaded() || !t->IsEngine()) continue;
    00886
    00887     /* Make sure that there are no free cars before next engine */
    00888     Train *u;
    00889     for (u = t; u->Next() != NULL && !u->Next()->IsEngine(); u = u->Next()) {}
    00890
    00891     if (u == t->other_multiheaded_part) continue;
    00892
    00893     /* Remove the part from the 'wrong' train */
    00894     RemoveFromConsist(t->other_multiheaded_part);
    00895     /* And add it to the 'right' train */
    00896     InsertInConsist(u, t->other_multiheaded_part);
    00897   }
    00898 }
    00899
    00904 static void NormaliseSubtypes(Train *chain)
    00905 {
    00906   /* Nothing to do */
    00907   if (chain == NULL) return;
    00908
    00909   /* We must be the first in the chain. */
    00910   assert(chain->Previous() == NULL);
    00911
    00912   /* Set the appropriate bits for the first in the chain. */
    00913   if (chain->IsWagon()) {
    00914     chain->SetFreeWagon();
    00915   } else {
    00916     assert(chain->IsEngine());
    00917     chain->SetFrontEngine();
    00918   }
    00919
    00920   /* Now clear the bits for the rest of the chain */
    00921   for (Train *t = chain->Next(); t != NULL; t = t->Next()) {
    00922     t->ClearFreeWagon();
    00923     t->ClearFrontEngine();
    00924   }
    00925 }
    00926
    00936 static CommandCost CheckNewTrain(Train *original_dst, Train *dst, Train *original_src, Train *src)
    00937 {
    00938   /* Just add 'new' engines and subtract the original ones.
    00939    * If that's less than or equal to 0 we can be sure we did
    00940    * not add any engines (read: trains) along the way. */
    00941   if ((src          != NULL && src->IsEngine()          ? 1 : 0) +
    00942       (dst          != NULL && dst->IsEngine()          ? 1 : 0) -
    00943       (original_src != NULL && original_src->IsEngine() ? 1 : 0) -
    00944       (original_dst != NULL && original_dst->IsEngine() ? 1 : 0) <= 0) {
    00945     return CommandCost();
    00946   }
    00947
    00948   /* Get a free unit number and check whether it's within the bounds.
    00949    * There will always be a maximum of one new train. */
    00950   if (GetFreeUnitNumber(VEH_TRAIN) <= _settings_game.vehicle.max_trains) return CommandCost();
    00951
    00952   return_cmd_error(STR_ERROR_TOO_MANY_VEHICLES_IN_GAME);
    00953 }
    00954
    00960 static CommandCost CheckTrainAttachment(Train *t)
    00961 {
    00962   /* No multi-part train, no need to check. */
    00963   if (t == NULL || t->Next() == NULL || !t->IsEngine()) return CommandCost();
    00964
    00965   /* The maximum length for a train. For each part we decrease this by one
    00966    * and if the result is negative the train is simply too long. */
    00967   int allowed_len = _settings_game.vehicle.max_train_length * TILE_SIZE - t->gcache.cached_veh_length;
    00968
    00969   Train *head = t;
    00970   Train *prev = t;
    00971
    00972   /* Break the prev -> t link so it always holds within the loop. */
    00973   t = t->Next();
    00974   prev->SetNext(NULL);
    00975
    00976   /* Make sure the cache is cleared. */
    00977   head->InvalidateNewGRFCache();
    00978
    00979   while (t != NULL) {
    00980     allowed_len -= t->gcache.cached_veh_length;
    00981
    00982     Train *next = t->Next();
    00983
    00984     /* Unlink the to-be-added piece; it is already unlinked from the previous
    00985      * part due to the fact that the prev -> t link is broken. */
    00986     t->SetNext(NULL);
    00987
    00988     /* Don't check callback for articulated or rear dual headed parts */
    00989     if (!t->IsArticulatedPart() && !t->IsRearDualheaded()) {
    00990       /* Back up and clear the first_engine data to avoid using wagon override group */
    00991       EngineID first_engine = t->gcache.first_engine;
    00992       t->gcache.first_engine = INVALID_ENGINE;
    00993
    00994       /* We don't want the cache to interfere. head's cache is cleared before
    00995        * the loop and after each callback does not need to be cleared here. */
    00996       t->InvalidateNewGRFCache();
    00997
    00998       uint16 callback = GetVehicleCallbackParent(CBID_TRAIN_ALLOW_WAGON_ATTACH, 0, 0, head->engine_type, t, head);
    00999
    01000       /* Restore original first_engine data */
    01001       t->gcache.first_engine = first_engine;
    01002
    01003       /* We do not want to remember any cached variables from the test run */
    01004       t->InvalidateNewGRFCache();
    01005       head->InvalidateNewGRFCache();
    01006
    01007       if (callback != CALLBACK_FAILED) {
    01008         /* A failing callback means everything is okay */
    01009         StringID error = STR_NULL;
    01010
    01011         if (head->GetGRF()->grf_version < 8) {
    01012           if (callback == 0xFD) error = STR_ERROR_INCOMPATIBLE_RAIL_TYPES;
    01013           if (callback  < 0xFD) error = GetGRFStringID(head->GetGRFID(), 0xD000 + callback);
    01014           if (callback >= 0x100) ErrorUnknownCallbackResult(head->GetGRFID(), CBID_TRAIN_ALLOW_WAGON_ATTACH, callback);
    01015         } else {
    01016           if (callback < 0x400) {
    01017             error = GetGRFStringID(head->GetGRFID(), 0xD000 + callback);
    01018           } else {
    01019             switch (callback) {
    01020               case 0x400: // allow if railtypes match (always the case for OpenTTD)
    01021               case 0x401: // allow
    01022                 break;
    01023
    01024               default:    // unknown reason -> disallow
    01025               case 0x402: // disallow attaching
    01026                 error = STR_ERROR_INCOMPATIBLE_RAIL_TYPES;
    01027                 break;
    01028             }
    01029           }
    01030         }
    01031
    01032         if (error != STR_NULL) return_cmd_error(error);
    01033       }
    01034     }
    01035
    01036     /* And link it to the new part. */
    01037     prev->SetNext(t);
    01038     prev = t;
    01039     t = next;
    01040   }
    01041
    01042   if (allowed_len < 0) return_cmd_error(STR_ERROR_TRAIN_TOO_LONG);
    01043   return CommandCost();
    01044 }
    01045
    01056 static CommandCost ValidateTrains(Train *original_dst, Train *dst, Train *original_src, Train *src, bool check_limit)
    01057 {
    01058   /* Check whether we may actually construct the trains. */
    01059   CommandCost ret = CheckTrainAttachment(src);
    01060   if (ret.Failed()) return ret;
    01061   ret = CheckTrainAttachment(dst);
    01062   if (ret.Failed()) return ret;
    01063
    01064   /* Check whether we need to build a new train. */
    01065   return check_limit ? CheckNewTrain(original_dst, dst, original_src, src) : CommandCost();
    01066 }
    01067
    01076 static void ArrangeTrains(Train **dst_head, Train *dst, Train **src_head, Train *src, bool move_chain)
    01077 {
    01078   /* First determine the front of the two resulting trains */
    01079   if (*src_head == *dst_head) {
    01080     /* If we aren't moving part(s) to a new train, we are just moving the
    01081      * front back and there is not destination head. */
    01082     *dst_head = NULL;
    01083   } else if (*dst_head == NULL) {
    01084     /* If we are moving to a new train the head of the move train would become
    01085      * the head of the new vehicle. */
    01086     *dst_head = src;
    01087   }
    01088
    01089   if (src == *src_head) {
    01090     /* If we are moving the front of a train then we are, in effect, creating
    01091      * a new head for the train. Point to that. Unless we are moving the whole
    01092      * train in which case there is not 'source' train anymore.
    01093      * In case we are a multiheaded part we want the complete thing to come
    01094      * with us, so src->GetNextUnit(), however... when we are e.g. a wagon
    01095      * that is followed by a rear multihead we do not want to include that. */
    01096     *src_head = move_chain ? NULL :
    01097         (src->IsMultiheaded() ? src->GetNextUnit() : src->GetNextVehicle());
    01098   }
    01099
    01100   /* Now it's just simply removing the part that we are going to move from the
    01101    * source train and *if* the destination is a not a new train add the chain
    01102    * at the destination location. */
    01103   RemoveFromConsist(src, move_chain);
    01104   if (*dst_head != src) InsertInConsist(dst, src);
    01105
    01106   /* Now normalise the dual heads, that is move the dual heads around in such
    01107    * a way that the head and rear of a dual head are in the same train */
    01108   NormaliseDualHeads(*src_head);
    01109   NormaliseDualHeads(*dst_head);
    01110 }
    01111
    01117 static void NormaliseTrainHead(Train *head)
    01118 {
    01119   /* Not much to do! */
    01120   if (head == NULL) return;
    01121
    01122   /* Tell the 'world' the train changed. */
    01123   head->ConsistChanged(false);
    01124   UpdateTrainGroupID(head);
    01125
    01126   /* Not a front engine, i.e. a free wagon chain. No need to do more. */
    01127   if (!head->IsFrontEngine()) return;
    01128
    01129   /* Update the refit button and window */
    01130   InvalidateWindowData(WC_VEHICLE_REFIT, head->index, VIWD_CONSIST_CHANGED);
    01131   SetWindowWidgetDirty(WC_VEHICLE_VIEW, head->index, WID_VV_REFIT);
    01132
    01133   /* If we don't have a unit number yet, set one. */
    01134   if (head->unitnumber != 0) return;
    01135   head->unitnumber = GetFreeUnitNumber(VEH_TRAIN);
    01136 }
    01137
    01150 CommandCost CmdMoveRailVehicle(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
    01151 {
    01152   VehicleID s = GB(p1, 0, 20);
    01153   VehicleID d = GB(p2, 0, 20);
    01154   bool move_chain = HasBit(p1, 20);
    01155
    01156   Train *src = Train::GetIfValid(s);
    01157   if (src == NULL) return CMD_ERROR;
    01158
    01159   CommandCost ret = CheckOwnership(src->owner);
    01160   if (ret.Failed()) return ret;
    01161
    01162   /* Do not allow moving crashed vehicles inside the depot, it is likely to cause asserts later */
    01163   if (src->vehstatus & VS_CRASHED) return CMD_ERROR;
    01164
    01165   /* if nothing is selected as destination, try and find a matching vehicle to drag to. */
    01166   Train *dst;
    01167   if (d == INVALID_VEHICLE) {
    01168     dst = src->IsEngine() ? NULL : FindGoodVehiclePos(src);
    01169   } else {
    01170     dst = Train::GetIfValid(d);
    01171     if (dst == NULL) return CMD_ERROR;
    01172
    01173     CommandCost ret = CheckOwnership(dst->owner);
    01174     if (ret.Failed()) return ret;
    01175
    01176     /* Do not allow appending to crashed vehicles, too */
    01177     if (dst->vehstatus & VS_CRASHED) return CMD_ERROR;
    01178   }
    01179
    01180   /* if an articulated part is being handled, deal with its parent vehicle */
    01181   src = src->GetFirstEnginePart();
    01182   if (dst != NULL) {
    01183     dst = dst->GetFirstEnginePart();
    01184   }
    01185
    01186   /* don't move the same vehicle.. */
    01187   if (src == dst) return CommandCost();
    01188
    01189   /* locate the head of the two chains */
    01190   Train *src_head = src->First();
    01191   Train *dst_head;
    01192   if (dst != NULL) {
    01193     dst_head = dst->First();
    01194     if (dst_head->tile != src_head->tile) return CMD_ERROR;
    01195     /* Now deal with articulated part of destination wagon */
    01196     dst = dst->GetLastEnginePart();
    01197   } else {
    01198     dst_head = NULL;
    01199   }
    01200
    01201   if (src->IsRearDualheaded()) return_cmd_error(STR_ERROR_REAR_ENGINE_FOLLOW_FRONT);
    01202
    01203   /* When moving all wagons, we can't have the same src_head and dst_head */
    01204   if (move_chain && src_head == dst_head) return CommandCost();
    01205
    01206   /* When moving a multiheaded part to be place after itself, bail out. */
    01207   if (!move_chain && dst != NULL && dst->IsRearDualheaded() && src == dst->other_multiheaded_part) return CommandCost();
    01208
    01209   /* Check if all vehicles in the source train are stopped inside a depot. */
    01210   if (!src_head->IsStoppedInDepot()) return_cmd_error(STR_ERROR_TRAINS_CAN_ONLY_BE_ALTERED_INSIDE_A_DEPOT);
    01211
    01212   /* Check if all vehicles in the destination train are stopped inside a depot. */
    01213   if (dst_head != NULL && !dst_head->IsStoppedInDepot()) return_cmd_error(STR_ERROR_TRAINS_CAN_ONLY_BE_ALTERED_INSIDE_A_DEPOT);
    01214
    01215   /* First make a backup of the order of the trains. That way we can do
    01216    * whatever we want with the order and later on easily revert. */
    01217   TrainList original_src;
    01218   TrainList original_dst;
    01219
    01220   MakeTrainBackup(original_src, src_head);
    01221   MakeTrainBackup(original_dst, dst_head);
    01222
    01223   /* Also make backup of the original heads as ArrangeTrains can change them.
    01224    * For the destination head we do not care if it is the same as the source
    01225    * head because in that case it's just a copy. */
    01226   Train *original_src_head = src_head;
    01227   Train *original_dst_head = (dst_head == src_head ? NULL : dst_head);
    01228
    01229   /* We want this information from before the rearrangement, but execute this after the validation.
    01230    * original_src_head can't be NULL; src is by definition != NULL, so src_head can't be NULL as
    01231    * src->GetFirst() always yields non-NULL, so eventually original_src_head != NULL as well. */
    01232   bool original_src_head_front_engine = original_src_head->IsFrontEngine();
    01233   bool original_dst_head_front_engine = original_dst_head != NULL && original_dst_head->IsFrontEngine();
    01234
    01235   /* (Re)arrange the trains in the wanted arrangement. */
    01236   ArrangeTrains(&dst_head, dst, &src_head, src, move_chain);
    01237
    01238   if ((flags & DC_AUTOREPLACE) == 0) {
    01239     /* If the autoreplace flag is set we do not need to test for the validity
    01240      * because we are going to revert the train to its original state. As we
    01241      * assume the original state was correct autoreplace can skip this. */
    01242     CommandCost ret = ValidateTrains(original_dst_head, dst_head, original_src_head, src_head, true);
    01243     if (ret.Failed()) {
    01244       /* Restore the train we had. */
    01245       RestoreTrainBackup(original_src);
    01246       RestoreTrainBackup(original_dst);
    01247       return ret;
    01248     }
    01249   }
    01250
    01251   /* do it? */
    01252   if (flags & DC_EXEC) {
    01253     /* Remove old heads from the statistics */
    01254     if (original_src_head_front_engine) GroupStatistics::CountVehicle(original_src_head, -1);
    01255     if (original_dst_head_front_engine) GroupStatistics::CountVehicle(original_dst_head, -1);
    01256
    01257     /* First normalise the sub types of the chains. */
    01258     NormaliseSubtypes(src_head);
    01259     NormaliseSubtypes(dst_head);
    01260
    01261     /* There are 14 different cases:
    01262      *  1) front engine gets moved to a new train, it stays a front engine.
    01263      *     a) the 'next' part is a wagon that becomes a free wagon chain.
    01264      *     b) the 'next' part is an engine that becomes a front engine.
    01265      *     c) there is no 'next' part, nothing else happens
    01266      *  2) front engine gets moved to another train, it is not a front engine anymore
    01267      *     a) the 'next' part is a wagon that becomes a free wagon chain.
    01268      *     b) the 'next' part is an engine that becomes a front engine.
    01269      *     c) there is no 'next' part, nothing else happens
    01270      *  3) front engine gets moved to later in the current train, it is not a front engine anymore.
    01271      *     a) the 'next' part is a wagon that becomes a free wagon chain.
    01272      *     b) the 'next' part is an engine that becomes a front engine.
    01273      *  4) free wagon gets moved
    01274      *     a) the 'next' part is a wagon that becomes a free wagon chain.
    01275      *     b) the 'next' part is an engine that becomes a front engine.
    01276      *     c) there is no 'next' part, nothing else happens
    01277      *  5) non front engine gets moved and becomes a new train, nothing else happens
    01278      *  6) non front engine gets moved within a train / to another train, nothing hapens
    01279      *  7) wagon gets moved, nothing happens
    01280      */
    01281     if (src == original_src_head && src->IsEngine() && !src->IsFrontEngine()) {
    01282       /* Cases #2 and #3: the front engine gets trashed. */
    01283       DeleteWindowById(WC_VEHICLE_VIEW, src->index);
    01284       DeleteWindowById(WC_VEHICLE_ORDERS, src->index);
    01285       DeleteWindowById(WC_VEHICLE_REFIT, src->index);
    01286       DeleteWindowById(WC_VEHICLE_DETAILS, src->index);
    01287       DeleteWindowById(WC_VEHICLE_TIMETABLE, src->index);
    01288       DeleteNewGRFInspectWindow(GSF_TRAINS, src->index);
    01289       SetWindowDirty(WC_COMPANY, _current_company);
    01290
    01291       /* Delete orders, group stuff and the unit number as we're not the
    01292        * front of any vehicle anymore. */
    01293       DeleteVehicleOrders(src);
    01294       RemoveVehicleFromGroup(src);
    01295       src->unitnumber = 0;
    01296     }
    01297
    01298     /* We weren't a front engine but are becoming one. So
    01299      * we should be put in the default group. */
    01300     if (original_src_head != src && dst_head == src) {
    01301       SetTrainGroupID(src, DEFAULT_GROUP);
    01302       SetWindowDirty(WC_COMPANY, _current_company);
    01303     }
    01304
    01305     /* Add new heads to statistics */
    01306     if (src_head != NULL && src_head->IsFrontEngine()) GroupStatistics::CountVehicle(src_head, 1);
    01307     if (dst_head != NULL && dst_head->IsFrontEngine()) GroupStatistics::CountVehicle(dst_head, 1);
    01308
    01309     /* Handle 'new engine' part of cases #1b, #2b, #3b, #4b and #5 in NormaliseTrainHead. */
    01310     NormaliseTrainHead(src_head);
    01311     NormaliseTrainHead(dst_head);
    01312
    01313     if ((flags & DC_NO_CARGO_CAP_CHECK) == 0) {
    01314       CheckCargoCapacity(src_head);
    01315       CheckCargoCapacity(dst_head);
    01316     }
    01317
    01318     if (src_head != NULL) src_head->First()->MarkDirty();
    01319     if (dst_head != NULL) dst_head->First()->MarkDirty();
    01320
    01321     /* We are undoubtedly changing something in the depot and train list. */
    01322     InvalidateWindowData(WC_VEHICLE_DEPOT, src->tile);
    01323     InvalidateWindowClassesData(WC_TRAINS_LIST, 0);
    01324   } else {
    01325     /* We don't want to execute what we're just tried. */
    01326     RestoreTrainBackup(original_src);
    01327     RestoreTrainBackup(original_dst);
    01328   }
    01329
    01330   return CommandCost();
    01331 }
    01332
    01344 CommandCost CmdSellRailWagon(DoCommandFlag flags, Vehicle *t, uint16 data, uint32 user)
    01345 {
    01346   /* Sell a chain of vehicles or not? */
    01347   bool sell_chain = HasBit(data, 0);
    01348
    01349   Train *v = Train::From(t)->GetFirstEnginePart();
    01350   Train *first = v->First();
    01351
    01352   if (v->IsRearDualheaded()) return_cmd_error(STR_ERROR_REAR_ENGINE_FOLLOW_FRONT);
    01353
    01354   /* First make a backup of the order of the train. That way we can do
    01355    * whatever we want with the order and later on easily revert. */
    01356   TrainList original;
    01357   MakeTrainBackup(original, first);
    01358
    01359   /* We need to keep track of the new head and the head of what we're going to sell. */
    01360   Train *new_head = first;
    01361   Train *sell_head = NULL;
    01362
    01363   /* Split the train in the wanted way. */
    01364   ArrangeTrains(&sell_head, NULL, &new_head, v, sell_chain);
    01365
    01366   /* We don't need to validate the second train; it's going to be sold. */
    01367   CommandCost ret = ValidateTrains(NULL, NULL, first, new_head, (flags & DC_AUTOREPLACE) == 0);
    01368   if (ret.Failed()) {
    01369     /* Restore the train we had. */
    01370     RestoreTrainBackup(original);
    01371     return ret;
    01372   }
    01373
    01374   CommandCost cost(EXPENSES_NEW_VEHICLES);
    01375   for (Train *t = sell_head; t != NULL; t = t->Next()) cost.AddCost(-t->value);
    01376
    01377   if (first->orders.list == NULL && !OrderList::CanAllocateItem()) {
    01378     return_cmd_error(STR_ERROR_NO_MORE_SPACE_FOR_ORDERS);
    01379   }
    01380
    01381   /* do it? */
    01382   if (flags & DC_EXEC) {
    01383     /* First normalise the sub types of the chain. */
    01384     NormaliseSubtypes(new_head);
    01385
    01386     if (v == first && v->IsEngine() && !sell_chain && new_head != NULL && new_head->IsFrontEngine()) {
    01387       /* We are selling the front engine. In this case we want to
    01388        * 'give' the order, unit number and such to the new head. */
    01389       new_head->orders.list = first->orders.list;
    01390       new_head->AddToShared(first);
    01391       DeleteVehicleOrders(first);
    01392
    01393       /* Copy other important data from the front engine */
    01394       new_head->CopyVehicleConfigAndStatistics(first);
    01395       GroupStatistics::CountVehicle(new_head, 1); // after copying over the profit
    01396     } else if (v->IsPrimaryVehicle() && data & (MAKE_ORDER_BACKUP_FLAG >> 20)) {
    01397       OrderBackup::Backup(v, user);
    01398     }
    01399
    01400     /* We need to update the information about the train. */
    01401     NormaliseTrainHead(new_head);
    01402
    01403     /* We are undoubtedly changing something in the depot and train list. */
    01404     InvalidateWindowData(WC_VEHICLE_DEPOT, v->tile);
    01405     InvalidateWindowClassesData(WC_TRAINS_LIST, 0);
    01406
    01407     /* Actually delete the sold 'goods' */
    01408     delete sell_head;
    01409   } else {
    01410     /* We don't want to execute what we're just tried. */
    01411     RestoreTrainBackup(original);
    01412   }
    01413
    01414   return cost;
    01415 }
    01416
    01417 void Train::UpdateDeltaXY(Direction direction)
    01418 {
    01419   /* Set common defaults. */
    01420   this->x_offs    = -1;
    01421   this->y_offs    = -1;
    01422   this->x_extent  =  3;
    01423   this->y_extent  =  3;
    01424   this->z_extent  =  6;
    01425   this->x_bb_offs =  0;
    01426   this->y_bb_offs =  0;
    01427
    01428   if (!IsDiagonalDirection(direction)) {
    01429     static const int _sign_table[] =
    01430     {
    01431       // x, y
    01432       -1, -1, // DIR_N
    01433       -1,  1, // DIR_E
    01434        1,  1, // DIR_S
    01435        1, -1, // DIR_W
    01436     };
    01437
    01438     int half_shorten = (VEHICLE_LENGTH - this->gcache.cached_veh_length) / 2;
    01439
    01440     /* For all straight directions, move the bound box to the centre of the vehicle, but keep the size. */
    01441     this->x_offs -= half_shorten * _sign_table[direction];
    01442     this->y_offs -= half_shorten * _sign_table[direction + 1];
    01443     this->x_extent += this->x_bb_offs = half_shorten * _sign_table[direction];
    01444     this->y_extent += this->y_bb_offs = half_shorten * _sign_table[direction + 1];
    01445   } else {
    01446     switch (direction) {
    01447         /* Shorten southern corner of the bounding box according the vehicle length
    01448          * and center the bounding box on the vehicle. */
    01449       case DIR_NE:
    01450         this->x_offs    = 1 - (this->gcache.cached_veh_length + 1) / 2;
    01451         this->x_extent  = this->gcache.cached_veh_length - 1;
    01452         this->x_bb_offs = -1;
    01453         break;
    01454
    01455       case DIR_NW:
    01456         this->y_offs    = 1 - (this->gcache.cached_veh_length + 1) / 2;
    01457         this->y_extent  = this->gcache.cached_veh_length - 1;
    01458         this->y_bb_offs = -1;
    01459         break;
    01460
    01461         /* Move northern corner of the bounding box down according to vehicle length
    01462          * and center the bounding box on the vehicle. */
    01463       case DIR_SW:
    01464         this->x_offs    = 1 + (this->gcache.cached_veh_length + 1) / 2 - VEHICLE_LENGTH;
    01465         this->x_extent  = VEHICLE_LENGTH - 1;
    01466         this->x_bb_offs = VEHICLE_LENGTH - this->gcache.cached_veh_length - 1;
    01467         break;
    01468
    01469       case DIR_SE:
    01470         this->y_offs    = 1 + (this->gcache.cached_veh_length + 1) / 2 - VEHICLE_LENGTH;
    01471         this->y_extent  = VEHICLE_LENGTH - 1;
    01472         this->y_bb_offs = VEHICLE_LENGTH - this->gcache.cached_veh_length - 1;
    01473         break;
    01474
    01475       default:
    01476         NOT_REACHED();
    01477     }
    01478   }
    01479 }
    01480
    01485 static void MarkTrainAsStuck(Train *v)
    01486 {
    01487   if (!HasBit(v->flags, VRF_TRAIN_STUCK)) {
    01488     /* It is the first time the problem occurred, set the "train stuck" flag. */
    01489     SetBit(v->flags, VRF_TRAIN_STUCK);
    01490
    01491     v->wait_counter = 0;
    01492
    01493     /* Stop train */
    01494     v->cur_speed = 0;
    01495     v->subspeed = 0;
    01496     v->SetLastSpeed();
    01497
    01498     SetWindowWidgetDirty(WC_VEHICLE_VIEW, v->index, WID_VV_START_STOP);
    01499   }
    01500 }
    01501
    01509 static void SwapTrainFlags(uint16 *swap_flag1, uint16 *swap_flag2)
    01510 {
    01511   uint16 flag1 = *swap_flag1;
    01512   uint16 flag2 = *swap_flag2;
    01513
    01514   /* Clear the flags */
    01515   ClrBit(*swap_flag1, GVF_GOINGUP_BIT);
    01516   ClrBit(*swap_flag1, GVF_GOINGDOWN_BIT);
    01517   ClrBit(*swap_flag2, GVF_GOINGUP_BIT);
    01518   ClrBit(*swap_flag2, GVF_GOINGDOWN_BIT);
    01519
    01520   /* Reverse the rail-flags (if needed) */
    01521   if (HasBit(flag1, GVF_GOINGUP_BIT)) {
    01522     SetBit(*swap_flag2, GVF_GOINGDOWN_BIT);
    01523   } else if (HasBit(flag1, GVF_GOINGDOWN_BIT)) {
    01524     SetBit(*swap_flag2, GVF_GOINGUP_BIT);
    01525   }
    01526   if (HasBit(flag2, GVF_GOINGUP_BIT)) {
    01527     SetBit(*swap_flag1, GVF_GOINGDOWN_BIT);
    01528   } else if (HasBit(flag2, GVF_GOINGDOWN_BIT)) {
    01529     SetBit(*swap_flag1, GVF_GOINGUP_BIT);
    01530   }
    01531 }
    01532
    01537 static void UpdateStatusAfterSwap(Train *v)
    01538 {
    01539   /* Reverse the direction. */
    01540   if (v->track != TRACK_BIT_DEPOT) v->direction = ReverseDir(v->direction);
    01541
    01542   /* Call the proper EnterTile function unless we are in a wormhole. */
    01543   if (v->track != TRACK_BIT_WORMHOLE) {
    01544     VehicleEnterTile(v, v->tile, v->x_pos, v->y_pos);
    01545   } else {
    01546     /* VehicleEnter_TunnelBridge() sets TRACK_BIT_WORMHOLE when the vehicle
    01547      * is on the last bit of the bridge head (frame == TILE_SIZE - 1).
    01548      * If we were swapped with such a vehicle, we have set TRACK_BIT_WORMHOLE,
    01549      * when we shouldn't have. Check if this is the case. */
    01550     TileIndex vt = TileVirtXY(v->x_pos, v->y_pos);
    01551     if (IsTileType(vt, MP_TUNNELBRIDGE)) {
    01552       VehicleEnterTile(v, vt, v->x_pos, v->y_pos);
    01553       if (v->track != TRACK_BIT_WORMHOLE && IsBridgeTile(v->tile)) {
    01554         /* We have just left the wormhole, possibly set the
    01555          * "goingdown" bit. UpdateInclination() can be used
    01556          * because we are at the border of the tile. */
    01557         VehicleUpdatePosition(v);
    01558         v->UpdateInclination(true, true);
    01559         return;
    01560       }
    01561     }
    01562   }
    01563
    01564   VehicleUpdatePosition(v);
    01565   v->UpdateViewport(true, true);
    01566 }
    01567
    01574 void ReverseTrainSwapVeh(Train *v, int l, int r)
    01575 {
    01576   Train *a, *b;
    01577
    01578   /* locate vehicles to swap */
    01579   for (a = v; l != 0; l--) a = a->Next();
    01580   for (b = v; r != 0; r--) b = b->Next();
    01581
    01582   if (a != b) {
    01583     /* swap the hidden bits */
    01584     {
    01585       uint16 tmp = (a->vehstatus & ~VS_HIDDEN) | (b->vehstatus & VS_HIDDEN);
    01586       b->vehstatus = (b->vehstatus & ~VS_HIDDEN) | (a->vehstatus & VS_HIDDEN);
    01587       a->vehstatus = tmp;
    01588     }
    01589
    01590     Swap(a->track, b->track);
    01591     Swap(a->direction, b->direction);
    01592     Swap(a->x_pos, b->x_pos);
    01593     Swap(a->y_pos, b->y_pos);
    01594     Swap(a->tile,  b->tile);
    01595     Swap(a->z_pos, b->z_pos);
    01596
    01597     SwapTrainFlags(&a->gv_flags, &b->gv_flags);
    01598
    01599     UpdateStatusAfterSwap(a);
    01600     UpdateStatusAfterSwap(b);
    01601   } else {
    01602     /* Swap GVF_GOINGUP_BIT/GVF_GOINGDOWN_BIT.
    01603      * This is a little bit redundant way, a->gv_flags will
    01604      * be (re)set twice, but it reduces code duplication */
    01605     SwapTrainFlags(&a->gv_flags, &a->gv_flags);
    01606     UpdateStatusAfterSwap(a);
    01607   }
    01608 }
    01609
    01610
    01616 static Vehicle *TrainOnTileEnum(Vehicle *v, void *)
    01617 {
    01618   return (v->type == VEH_TRAIN) ? v : NULL;
    01619 }
    01620
    01621
    01628 static Vehicle *TrainApproachingCrossingEnum(Vehicle *v, void *data)
    01629 {
    01630   if (v->type != VEH_TRAIN || (v->vehstatus & VS_CRASHED)) return NULL;
    01631
    01632   Train *t = Train::From(v);
    01633   if (!t->IsFrontEngine()) return NULL;
    01634
    01635   TileIndex tile = *(TileIndex *)data;
    01636
    01637   if (TrainApproachingCrossingTile(t) != tile) return NULL;
    01638
    01639   return t;
    01640 }
    01641
    01642
    01649 static bool TrainApproachingCrossing(TileIndex tile)
    01650 {
    01651   assert(IsLevelCrossingTile(tile));
    01652
    01653   DiagDirection dir = AxisToDiagDir(GetCrossingRailAxis(tile));
    01654   TileIndex tile_from = tile + TileOffsByDiagDir(dir);
    01655
    01656   if (HasVehicleOnPos(tile_from, &tile, &TrainApproachingCrossingEnum)) return true;
    01657
    01658   dir = ReverseDiagDir(dir);
    01659   tile_from = tile + TileOffsByDiagDir(dir);
    01660
    01661   return HasVehicleOnPos(tile_from, &tile, &TrainApproachingCrossingEnum);
    01662 }
    01663
    01664
    01671 void UpdateLevelCrossing(TileIndex tile, bool sound)
    01672 {
    01673   assert(IsLevelCrossingTile(tile));
    01674
    01675   /* train on crossing || train approaching crossing || reserved */
    01676   bool new_state = HasVehicleOnPos(tile, NULL, &TrainOnTileEnum) || TrainApproachingCrossing(tile) || HasCrossingReservation(tile);
    01677
    01678   if (new_state != IsCrossingBarred(tile)) {
    01679     if (new_state && sound) {
    01680       if (_settings_client.sound.ambient) SndPlayTileFx(SND_0E_LEVEL_CROSSING, tile);
    01681     }
    01682     SetCrossingBarred(tile, new_state);
    01683     MarkTileDirtyByTile(tile);
    01684   }
    01685 }
    01686
    01687
    01693 static inline void MaybeBarCrossingWithSound(TileIndex tile)
    01694 {
    01695   if (!IsCrossingBarred(tile)) {
    01696     BarCrossing(tile);
    01697     if (_settings_client.sound.ambient) SndPlayTileFx(SND_0E_LEVEL_CROSSING, tile);
    01698     MarkTileDirtyByTile(tile);
    01699   }
    01700 }
    01701
    01702
    01708 static void AdvanceWagonsBeforeSwap(Train *v)
    01709 {
    01710   Train *base = v;
    01711   Train *first = base; // first vehicle to move
    01712   Train *last = v->Last(); // last vehicle to move
    01713   uint length = CountVehiclesInChain(v);
    01714
    01715   while (length > 2) {
    01716     last = last->Previous();
    01717     first = first->Next();
    01718
    01719     int differential = base->CalcNextVehicleOffset() - last->CalcNextVehicleOffset();
    01720
    01721     /* do not update images now
    01722      * negative differential will be handled in AdvanceWagonsAfterSwap() */
    01723     for (int i = 0; i < differential; i++) TrainController(first, last->Next());
    01724
    01725     base = first; // == base->Next()
    01726     length -= 2;
    01727   }
    01728 }
    01729
    01730
    01736 static void AdvanceWagonsAfterSwap(Train *v)
    01737 {
    01738   /* first of all, fix the situation when the train was entering a depot */
    01739   Train *dep = v; // last vehicle in front of just left depot
    01740   while (dep->Next() != NULL && (dep->track == TRACK_BIT_DEPOT || dep->Next()->track != TRACK_BIT_DEPOT)) {
    01741     dep = dep->Next(); // find first vehicle outside of a depot, with next vehicle inside a depot
    01742   }
    01743
    01744   Train *leave = dep->Next(); // first vehicle in a depot we are leaving now
    01745
    01746   if (leave != NULL) {
    01747     /* 'pull' next wagon out of the depot, so we won't miss it (it could stay in depot forever) */
    01748     int d = TicksToLeaveDepot(dep);
    01749
    01750     if (d <= 0) {
    01751       leave->vehstatus &= ~VS_HIDDEN; // move it out of the depot
    01752       leave->track = TrackToTrackBits(GetRailDepotTrack(leave->tile));
    01753       for (int i = 0; i >= d; i--) TrainController(leave, NULL); // maybe move it, and maybe let another wagon leave
    01754     }
    01755   } else {
    01756     dep = NULL; // no vehicle in a depot, so no vehicle leaving a depot
    01757   }
    01758
    01759   Train *base = v;
    01760   Train *first = base; // first vehicle to move
    01761   Train *last = v->Last(); // last vehicle to move
    01762   uint length = CountVehiclesInChain(v);
    01763
    01764   /* We have to make sure all wagons that leave a depot because of train reversing are moved correctly
    01765    * they have already correct spacing, so we have to make sure they are moved how they should */
    01766   bool nomove = (dep == NULL); // If there is no vehicle leaving a depot, limit the number of wagons moved immediately.
    01767
    01768   while (length > 2) {
    01769     /* we reached vehicle (originally) in front of a depot, stop now
    01770      * (we would move wagons that are already moved with new wagon length). */
    01771     if (base == dep) break;
    01772
    01773     /* the last wagon was that one leaving a depot, so do not move it anymore */
    01774     if (last == dep) nomove = true;
    01775
    01776     last = last->Previous();
    01777     first = first->Next();
    01778
    01779     int differential = last->CalcNextVehicleOffset() - base->CalcNextVehicleOffset();
    01780
    01781     /* do not update images now */
    01782     for (int i = 0; i < differential; i++) TrainController(first, (nomove ? last->Next() : NULL));
    01783
    01784     base = first; // == base->Next()
    01785     length -= 2;
    01786   }
    01787 }
    01788
    01793 void ReverseTrainDirection(Train *v)
    01794 {
    01795   if (IsRailDepotTile(v->tile)) {
    01796     InvalidateWindowData(WC_VEHICLE_DEPOT, v->tile);
    01797   }
    01798
    01799   /* Clear path reservation in front if train is not stuck. */
    01800   if (!HasBit(v->flags, VRF_TRAIN_STUCK)) FreeTrainTrackReservation(v);
    01801
    01802   /* Check if we were approaching a rail/road-crossing */
    01803   TileIndex crossing = TrainApproachingCrossingTile(v);
    01804
    01805   /* count number of vehicles */
    01806   int r = CountVehiclesInChain(v) - 1;  // number of vehicles - 1
    01807
    01808   AdvanceWagonsBeforeSwap(v);
    01809
    01810   /* swap start<>end, start+1<>end-1, ... */
    01811   int l = 0;
    01812   do {
    01813     ReverseTrainSwapVeh(v, l++, r--);
    01814   } while (l <= r);
    01815
    01816   AdvanceWagonsAfterSwap(v);
    01817
    01818   if (IsRailDepotTile(v->tile)) {
    01819     InvalidateWindowData(WC_VEHICLE_DEPOT, v->tile);
    01820   }
    01821
    01822   ToggleBit(v->flags, VRF_TOGGLE_REVERSE);
    01823
    01824   ClrBit(v->flags, VRF_REVERSING);
    01825
    01826   /* recalculate cached data */
    01827   v->ConsistChanged(true);
    01828
    01829   /* update all images */
    01830   for (Train *u = v; u != NULL; u = u->Next()) u->UpdateViewport(false, false);
    01831
    01832   /* update crossing we were approaching */
    01833   if (crossing != INVALID_TILE) UpdateLevelCrossing(crossing);
    01834
    01835   /* maybe we are approaching crossing now, after reversal */
    01836   crossing = TrainApproachingCrossingTile(v);
    01837   if (crossing != INVALID_TILE) MaybeBarCrossingWithSound(crossing);
    01838
    01839   /* If we are inside a depot after reversing, don't bother with path reserving. */
    01840   if (v->track == TRACK_BIT_DEPOT) {
    01841     /* Can't be stuck here as inside a depot is always a safe tile. */
    01842     if (HasBit(v->flags, VRF_TRAIN_STUCK)) SetWindowWidgetDirty(WC_VEHICLE_VIEW, v->index, WID_VV_START_STOP);
    01843     ClrBit(v->flags, VRF_TRAIN_STUCK);
    01844     return;
    01845   }
    01846
    01847   /* TrainExitDir does not always produce the desired dir for depots and
    01848    * tunnels/bridges that is needed for UpdateSignalsOnSegment. */
    01849   DiagDirection dir = TrainExitDir(v->direction, v->track);
    01850   if (IsRailDepotTile(v->tile) || IsTileType(v->tile, MP_TUNNELBRIDGE)) dir = INVALID_DIAGDIR;
    01851
    01852   if (UpdateSignalsOnSegment(v->tile, dir, v->owner) == SIGSEG_PBS || _settings_game.pf.reserve_paths) {
    01853     /* If we are currently on a tile with conventional signals, we can't treat the
    01854      * current tile as a safe tile or we would enter a PBS block without a reservation. */
    01855     bool first_tile_okay = !(IsTileType(v->tile, MP_RAILWAY) &&
    01856       HasSignalOnTrackdir(v->tile, v->GetVehicleTrackdir()) &&
    01857       !IsPbsSignal(GetSignalType(v->tile, FindFirstTrack(v->track))));
    01858
    01859     /* If we are on a depot tile facing outwards, do not treat the current tile as safe. */
    01860     if (IsRailDepotTile(v->tile) && TrackdirToExitdir(v->GetVehicleTrackdir()) == GetRailDepotDirection(v->tile)) first_tile_okay = false;
    01861
    01862     if (IsRailStationTile(v->tile)) SetRailStationPlatformReservation(v->tile, TrackdirToExitdir(v->GetVehicleTrackdir()), true);
    01863     if (TryPathReserve(v, false, first_tile_okay)) {
    01864       /* Do a look-ahead now in case our current tile was already a safe tile. */
    01865       CheckNextTrainTile(v);
    01866     } else if (v->current_order.GetType() != OT_LOADING) {
    01867       /* Do not wait for a way out when we're still loading */
    01868       MarkTrainAsStuck(v);
    01869     }
    01870   } else if (HasBit(v->flags, VRF_TRAIN_STUCK)) {
    01871     /* A train not inside a PBS block can't be stuck. */
    01872     ClrBit(v->flags, VRF_TRAIN_STUCK);
    01873     v->wait_counter = 0;
    01874   }
    01875 }
    01876
    01886 CommandCost CmdReverseTrainDirection(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
    01887 {
    01888   Train *v = Train::GetIfValid(p1);
    01889   if (v == NULL) return CMD_ERROR;
    01890
    01891   CommandCost ret = CheckOwnership(v->owner);
    01892   if (ret.Failed()) return ret;
    01893
    01894   if (p2 != 0) {
    01895     /* turn a single unit around */
    01896
    01897     if (v->IsMultiheaded() || HasBit(EngInfo(v->engine_type)->callback_mask, CBM_VEHICLE_ARTIC_ENGINE)) {
    01898       return_cmd_error(STR_ERROR_CAN_T_REVERSE_DIRECTION_RAIL_VEHICLE_MULTIPLE_UNITS);
    01899     }
    01900     if (!HasBit(EngInfo(v->engine_type)->misc_flags, EF_RAIL_FLIPS)) return CMD_ERROR;
    01901
    01902     Train *front = v->First();
    01903     /* make sure the vehicle is stopped in the depot */
    01904     if (!front->IsStoppedInDepot()) {
    01905       return_cmd_error(STR_ERROR_TRAINS_CAN_ONLY_BE_ALTERED_INSIDE_A_DEPOT);
    01906     }
    01907
    01908     if (flags & DC_EXEC) {
    01909       ToggleBit(v->flags, VRF_REVERSE_DIRECTION);
    01910
    01911       front->ConsistChanged(false);
    01912       SetWindowDirty(WC_VEHICLE_DEPOT, front->tile);
    01913       SetWindowDirty(WC_VEHICLE_DETAILS, front->index);
    01914       SetWindowDirty(WC_VEHICLE_VIEW, front->index);
    01915       SetWindowClassesDirty(WC_TRAINS_LIST);
    01916     }
    01917   } else {
    01918     /* turn the whole train around */
    01919     if ((v->vehstatus & VS_CRASHED) || v->breakdown_ctr != 0) return CMD_ERROR;
    01920
    01921     if (flags & DC_EXEC) {
    01922       /* Properly leave the station if we are loading and won't be loading anymore */
    01923       if (v->current_order.IsType(OT_LOADING)) {
    01924         const Vehicle *last = v;
    01925         while (last->Next() != NULL) last = last->Next();
    01926
    01927         /* not a station || different station --> leave the station */
    01928         if (!IsTileType(last->tile, MP_STATION) || GetStationIndex(last->tile) != GetStationIndex(v->tile)) {
    01929           v->LeaveStation();
    01930         }
    01931       }
    01932
    01933       /* We cancel any 'skip signal at dangers' here */
    01934       v->force_proceed = TFP_NONE;
    01935       SetWindowDirty(WC_VEHICLE_VIEW, v->index);
    01936
    01937       if (_settings_game.vehicle.train_acceleration_model != AM_ORIGINAL && v->cur_speed != 0) {
    01938         ToggleBit(v->flags, VRF_REVERSING);
    01939       } else {
    01940         v->cur_speed = 0;
    01941         v->SetLastSpeed();
    01942         HideFillingPercent(&v->fill_percent_te_id);
    01943         ReverseTrainDirection(v);
    01944       }
    01945     }
    01946   }
    01947   return CommandCost();
    01948 }
    01949
    01959 CommandCost CmdForceTrainProceed(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
    01960 {
    01961   Train *t = Train::GetIfValid(p1);
    01962   if (t == NULL) return CMD_ERROR;
    01963
    01964   if (!t->IsPrimaryVehicle()) return CMD_ERROR;
    01965
    01966   CommandCost ret = CheckOwnership(t->owner);
    01967   if (ret.Failed()) return ret;
    01968
    01969
    01970   if (flags & DC_EXEC) {
    01971     /* If we are forced to proceed, cancel that order.
    01972      * If we are marked stuck we would want to force the train
    01973      * to proceed to the next signal. In the other cases we
    01974      * would like to pass the signal at danger and run till the
    01975      * next signal we encounter. */
    01976     t->force_proceed = t->force_proceed == TFP_SIGNAL ? TFP_NONE : HasBit(t->flags, VRF_TRAIN_STUCK) || t->IsChainInDepot() ? TFP_STUCK : TFP_SIGNAL;
    01977     SetWindowDirty(WC_VEHICLE_VIEW, t->index);
    01978   }
    01979
    01980   return CommandCost();
    01981 }
    01982
    01990 static FindDepotData FindClosestTrainDepot(Train *v, int max_distance)
    01991 {
    01992   assert(!(v->vehstatus & VS_CRASHED));
    01993
    01994   if (IsRailDepotTile(v->tile)) return FindDepotData(v->tile, 0);
    01995
    01996   PBSTileInfo origin = FollowTrainReservation(v);
    01997   if (IsRailDepotTile(origin.tile)) return FindDepotData(origin.tile, 0);
    01998
    01999   switch (_settings_game.pf.pathfinder_for_trains) {
    02000     case VPF_NPF: return NPFTrainFindNearestDepot(v, max_distance);
    02001     case VPF_YAPF: return YapfTrainFindNearestDepot(v, max_distance);
    02002
    02003     default: NOT_REACHED();
    02004   }
    02005 }
    02006
    02014 bool Train::FindClosestDepot(TileIndex *location, DestinationID *destination, bool *reverse)
    02015 {
    02016   FindDepotData tfdd = FindClosestTrainDepot(this, 0);
    02017   if (tfdd.best_length == UINT_MAX) return false;
    02018
    02019   if (location    != NULL) *location    = tfdd.tile;
    02020   if (destination != NULL) *destination = GetDepotIndex(tfdd.tile);
    02021   if (reverse     != NULL) *reverse     = tfdd.reverse;
    02022
    02023   return true;
    02024 }
    02025
    02027 void Train::PlayLeaveStationSound() const
    02028 {
    02029   static const SoundFx sfx[] = {
    02030     SND_04_TRAIN,
    02031     SND_0A_TRAIN_HORN,
    02032     SND_0A_TRAIN_HORN,
    02033     SND_47_MAGLEV_2,
    02034     SND_41_MAGLEV
    02035   };
    02036
    02037   if (PlayVehicleSound(this, VSE_START)) return;
    02038
    02039   EngineID engtype = this->engine_type;
    02040   SndPlayVehicleFx(sfx[RailVehInfo(engtype)->engclass], this);
    02041 }
    02042
    02047 static void CheckNextTrainTile(Train *v)
    02048 {
    02049   /* Don't do any look-ahead if path_backoff_interval is 255. */
    02050   if (_settings_game.pf.path_backoff_interval == 255) return;
    02051
    02052   /* Exit if we are inside a depot. */
    02053   if (v->track == TRACK_BIT_DEPOT) return;
    02054
    02055   switch (v->current_order.GetType()) {
    02056     /* Exit if we reached our destination depot. */
    02057     case OT_GOTO_DEPOT:
    02058       if (v->tile == v->dest_tile) return;
    02059       break;
    02060
    02061     case OT_GOTO_WAYPOINT:
    02062       /* If we reached our waypoint, make sure we see that. */
    02063       if (IsRailWaypointTile(v->tile) && GetStationIndex(v->tile) == v->current_order.GetDestination()) ProcessOrders(v);
    02064       break;
    02065
    02066     case OT_NOTHING:
    02067     case OT_LEAVESTATION:
    02068     case OT_LOADING:
    02069       /* Exit if the current order doesn't have a destination, but the train has orders. */
    02070       if (v->GetNumOrders() > 0) return;
    02071       break;
    02072
    02073     default:
    02074       break;
    02075   }
    02076   /* Exit if we are on a station tile and are going to stop. */
    02077   if (IsRailStationTile(v->tile) && v->current_order.ShouldStopAtStation(v, GetStationIndex(v->tile))) return;
    02078
    02079   Trackdir td = v->GetVehicleTrackdir();
    02080
    02081   /* On a tile with a red non-pbs signal, don't look ahead. */
    02082   if (IsTileType(v->tile, MP_RAILWAY) && HasSignalOnTrackdir(v->tile, td) &&
    02083       !IsPbsSignal(GetSignalType(v->tile, TrackdirToTrack(td))) &&
    02084       GetSignalStateByTrackdir(v->tile, td) == SIGNAL_STATE_RED) return;
    02085
    02086   CFollowTrackRail ft(v);
    02087   if (!ft.Follow(v->tile, td)) return;
    02088
    02089   if (!HasReservedTracks(ft.m_new_tile, TrackdirBitsToTrackBits(ft.m_new_td_bits))) {
    02090     /* Next tile is not reserved. */
    02091     if (KillFirstBit(ft.m_new_td_bits) == TRACKDIR_BIT_NONE) {
    02092       if (HasPbsSignalOnTrackdir(ft.m_new_tile, FindFirstTrackdir(ft.m_new_td_bits))) {
    02093         /* If the next tile is a PBS signal, try to make a reservation. */
    02094         TrackBits tracks = TrackdirBitsToTrackBits(ft.m_new_td_bits);
    02095         if (_settings_game.pf.forbid_90_deg) {
    02096           tracks &= ~TrackCrossesTracks(TrackdirToTrack(ft.m_old_td));
    02097         }
    02098         ChooseTrainTrack(v, ft.m_new_tile, ft.m_exitdir, tracks, false, NULL, false);
    02099       }
    02100     }
    02101   }
    02102 }
    02103
    02109 static bool CheckTrainStayInDepot(Train *v)
    02110 {
    02111   /* bail out if not all wagons are in the same depot or not in a depot at all */
    02112   for (const Train *u = v; u != NULL; u = u->Next()) {
    02113     if (u->track != TRACK_BIT_DEPOT || u->tile != v->tile) return false;
    02114   }
    02115
    02116   /* if the train got no power, then keep it in the depot */
    02117   if (v->gcache.cached_power == 0) {
    02118     v->vehstatus |= VS_STOPPED;
    02119     SetWindowDirty(WC_VEHICLE_DEPOT, v->tile);
    02120     return true;
    02121   }
    02122
    02123   SigSegState seg_state;
    02124
    02125   if (v->force_proceed == TFP_NONE) {
    02126     /* force proceed was not pressed */
    02127     if (++v->wait_counter < 37) {
    02128       SetWindowClassesDirty(WC_TRAINS_LIST);
    02129       return true;
    02130     }
    02131
    02132     v->wait_counter = 0;
    02133
    02134     seg_state = _settings_game.pf.reserve_paths ? SIGSEG_PBS : UpdateSignalsOnSegment(v->tile, INVALID_DIAGDIR, v->owner);
    02135     if (seg_state == SIGSEG_FULL || HasDepotReservation(v->tile)) {
    02136       /* Full and no PBS signal in block or depot reserved, can't exit. */
    02137       SetWindowClassesDirty(WC_TRAINS_LIST);
    02138       return true;
    02139     }
    02140   } else {
    02141     seg_state = _settings_game.pf.reserve_paths ? SIGSEG_PBS : UpdateSignalsOnSegment(v->tile, INVALID_DIAGDIR, v->owner);
    02142   }
    02143
    02144   /* We are leaving a depot, but have to go to the exact same one; re-enter */
    02145   if (v->current_order.IsType(OT_GOTO_DEPOT) && v->tile == v->dest_tile) {
    02146     /* We need to have a reservation for this to work. */
    02147     if (HasDepotReservation(v->tile)) return true;
    02148     SetDepotReservation(v->tile, true);
    02149     VehicleEnterDepot(v);
    02150     return true;
    02151   }
    02152
    02153   /* Only leave when we can reserve a path to our destination. */
    02154   if (seg_state == SIGSEG_PBS && !TryPathReserve(v) && v->force_proceed == TFP_NONE) {
    02155     /* No path and no force proceed. */
    02156     SetWindowClassesDirty(WC_TRAINS_LIST);
    02157     MarkTrainAsStuck(v);
    02158     return true;
    02159   }
    02160
    02161   SetDepotReservation(v->tile, true);
    02162   if (_settings_client.gui.show_track_reservation) MarkTileDirtyByTile(v->tile);
    02163
    02164   VehicleServiceInDepot(v);
    02165   SetWindowClassesDirty(WC_TRAINS_LIST);
    02166   v->PlayLeaveStationSound();
    02167
    02168   v->track = TRACK_BIT_X;
    02169   if (v->direction & 2) v->track = TRACK_BIT_Y;
    02170
    02171   v->vehstatus &= ~VS_HIDDEN;
    02172   v->cur_speed = 0;
    02173
    02174   v->UpdateViewport(true, true);
    02175   VehicleUpdatePosition(v);
    02176   UpdateSignalsOnSegment(v->tile, INVALID_DIAGDIR, v->owner);
    02177   v->UpdateAcceleration();
    02178   InvalidateWindowData(WC_VEHICLE_DEPOT, v->tile);
    02179
    02180   return false;
    02181 }
    02182
    02189 static void ClearPathReservation(const Train *v, TileIndex tile, Trackdir track_dir)
    02190 {
    02191   DiagDirection dir = TrackdirToExitdir(track_dir);
    02192
    02193   if (IsTileType(tile, MP_TUNNELBRIDGE)) {
    02194     /* Are we just leaving a tunnel/bridge? */
    02195     if (GetTunnelBridgeDirection(tile) == ReverseDiagDir(dir)) {
    02196       TileIndex end = GetOtherTunnelBridgeEnd(tile);
    02197
    02198       if (TunnelBridgeIsFree(tile, end, v).Succeeded()) {
    02199         /* Free the reservation only if no other train is on the tiles. */
    02200         SetTunnelBridgeReservation(tile, false);
    02201         SetTunnelBridgeReservation(end, false);
    02202
    02203         if (_settings_client.gui.show_track_reservation) {
    02204           MarkTileDirtyByTile(tile);
    02205           MarkTileDirtyByTile(end);
    02206         }
    02207       }
    02208     }
    02209   } else if (IsRailStationTile(tile)) {
    02210     TileIndex new_tile = TileAddByDiagDir(tile, dir);
    02211     /* If the new tile is not a further tile of the same station, we
    02212      * clear the reservation for the whole platform. */
    02213     if (!IsCompatibleTrainStationTile(new_tile, tile)) {
    02214       SetRailStationPlatformReservation(tile, ReverseDiagDir(dir), false);
    02215     }
    02216   } else {
    02217     /* Any other tile */
    02218     UnreserveRailTrack(tile, TrackdirToTrack(track_dir));
    02219   }
    02220 }
    02221
    02228 void FreeTrainTrackReservation(const Train *v, TileIndex origin, Trackdir orig_td)
    02229 {
    02230   assert(v->IsFrontEngine());
    02231
    02232   TileIndex tile = origin != INVALID_TILE ? origin : v->tile;
    02233   Trackdir  td = orig_td != INVALID_TRACKDIR ? orig_td : v->GetVehicleTrackdir();
    02234   bool      free_tile = tile != v->tile || !(IsRailStationTile(v->tile) || IsTileType(v->tile, MP_TUNNELBRIDGE));
    02235   StationID station_id = IsRailStationTile(v->tile) ? GetStationIndex(v->tile) : INVALID_STATION;
    02236
    02237   /* Can't be holding a reservation if we enter a depot. */
    02238   if (IsRailDepotTile(tile) && TrackdirToExitdir(td) != GetRailDepotDirection(tile)) return;
    02239   if (v->track == TRACK_BIT_DEPOT) {
    02240     /* Front engine is in a depot. We enter if some part is not in the depot. */
    02241     for (const Train *u = v; u != NULL; u = u->Next()) {
    02242       if (u->track != TRACK_BIT_DEPOT || u->tile != v->tile) return;
    02243     }
    02244   }
    02245   /* Don't free reservation if it's not ours. */
    02246   if (TracksOverlap(GetReservedTrackbits(tile) | TrackToTrackBits(TrackdirToTrack(td)))) return;
    02247
    02248   CFollowTrackRail ft(v, GetRailTypeInfo(v->railtype)->compatible_railtypes);
    02249   while (ft.Follow(tile, td)) {
    02250     tile = ft.m_new_tile;
    02251     TrackdirBits bits = ft.m_new_td_bits & TrackBitsToTrackdirBits(GetReservedTrackbits(tile));
    02252     td = RemoveFirstTrackdir(&bits);
    02253     assert(bits == TRACKDIR_BIT_NONE);
    02254
    02255     if (!IsValidTrackdir(td)) break;
    02256
    02257     if (IsTileType(tile, MP_RAILWAY)) {
    02258       if (HasSignalOnTrackdir(tile, td) && !IsPbsSignal(GetSignalType(tile, TrackdirToTrack(td)))) {
    02259         /* Conventional signal along trackdir: remove reservation and stop. */
    02260         UnreserveRailTrack(tile, TrackdirToTrack(td));
    02261         break;
    02262       }
    02263       if (HasPbsSignalOnTrackdir(tile, td)) {
    02264         if (GetSignalStateByTrackdir(tile, td) == SIGNAL_STATE_RED) {
    02265           /* Red PBS signal? Can't be our reservation, would be green then. */
    02266           break;
    02267         } else {
    02268           /* Turn the signal back to red. */
    02269           SetSignalStateByTrackdir(tile, td, SIGNAL_STATE_RED);
    02270           MarkTileDirtyByTile(tile);
    02271         }
    02272       } else if (HasSignalOnTrackdir(tile, ReverseTrackdir(td)) && IsOnewaySignal(tile, TrackdirToTrack(td))) {
    02273         break;
    02274       }
    02275     }
    02276
    02277     /* Don't free first station/bridge/tunnel if we are on it. */
    02278     if (free_tile || (!(ft.m_is_station && GetStationIndex(ft.m_new_tile) == station_id) && !ft.m_is_tunnel && !ft.m_is_bridge)) ClearPathReservation(v, tile, td);
    02279
    02280     free_tile = true;
    02281   }
    02282 }
    02283
    02284 static const byte _initial_tile_subcoord[6][4][3] = {
    02285 {{ 15, 8, 1 }, { 0, 0, 0 }, { 0, 8, 5 }, { 0,  0, 0 }},
    02286 {{  0, 0, 0 }, { 8, 0, 3 }, { 0, 0, 0 }, { 8, 15, 7 }},
    02287 {{  0, 0, 0 }, { 7, 0, 2 }, { 0, 7, 6 }, { 0,  0, 0 }},
    02288 {{ 15, 8, 2 }, { 0, 0, 0 }, { 0, 0, 0 }, { 8, 15, 6 }},
    02289 {{ 15, 7, 0 }, { 8, 0, 4 }, { 0, 0, 0 }, { 0,  0, 0 }},
    02290 {{  0, 0, 0 }, { 0, 0, 0 }, { 0, 8, 4 }, { 7, 15, 0 }},
    02291 };
    02292
    02305 static Track DoTrainPathfind(const Train *v, TileIndex tile, DiagDirection enterdir, TrackBits tracks, bool &path_found, bool do_track_reservation, PBSTileInfo *dest)
    02306 {
    02307   switch (_settings_game.pf.pathfinder_for_trains) {
    02308     case VPF_NPF: return NPFTrainChooseTrack(v, tile, enterdir, tracks, path_found, do_track_reservation, dest);
    02309     case VPF_YAPF: return YapfTrainChooseTrack(v, tile, enterdir, tracks, path_found, do_track_reservation, dest);
    02310
    02311     default: NOT_REACHED();
    02312   }
    02313 }
    02314
    02320 static PBSTileInfo ExtendTrainReservation(const Train *v, TrackBits *new_tracks, DiagDirection *enterdir)
    02321 {
    02322   PBSTileInfo origin = FollowTrainReservation(v);
    02323
    02324   CFollowTrackRail ft(v);
    02325
    02326   TileIndex tile = origin.tile;
    02327   Trackdir  cur_td = origin.trackdir;
    02328   while (ft.Follow(tile, cur_td)) {
    02329     if (KillFirstBit(ft.m_new_td_bits) == TRACKDIR_BIT_NONE) {
    02330       /* Possible signal tile. */
    02331       if (HasOnewaySignalBlockingTrackdir(ft.m_new_tile, FindFirstTrackdir(ft.m_new_td_bits))) break;
    02332     }
    02333
    02334     if (_settings_game.pf.forbid_90_deg) {
    02335       ft.m_new_td_bits &= ~TrackdirCrossesTrackdirs(ft.m_old_td);
    02336       if (ft.m_new_td_bits == TRACKDIR_BIT_NONE) break;
    02337     }
    02338
    02339     /* Station, depot or waypoint are a possible target. */
    02340     bool target_seen = ft.m_is_station || (IsTileType(ft.m_new_tile, MP_RAILWAY) && !IsPlainRail(ft.m_new_tile));
    02341     if (target_seen || KillFirstBit(ft.m_new_td_bits) != TRACKDIR_BIT_NONE) {
    02342       /* Choice found or possible target encountered.
    02343        * On finding a possible target, we need to stop and let the pathfinder handle the
    02344        * remaining path. This is because we don't know if this target is in one of our
    02345        * orders, so we might cause pathfinding to fail later on if we find a choice.
    02346        * This failure would cause a bogous call to TryReserveSafePath which might reserve
    02347        * a wrong path not leading to our next destination. */
    02348       if (HasReservedTracks(ft.m_new_tile, TrackdirBitsToTrackBits(TrackdirReachesTrackdirs(ft.m_old_td)))) break;
    02349
    02350       /* If we did skip some tiles, backtrack to the first skipped tile so the pathfinder
    02351        * actually starts its search at the first unreserved tile. */
    02352       if (ft.m_tiles_skipped != 0) ft.m_new_tile -= TileOffsByDiagDir(ft.m_exitdir) * ft.m_tiles_skipped;
    02353
    02354       /* Choice found, path valid but not okay. Save info about the choice tile as well. */
    02355       if (new_tracks != NULL) *new_tracks = TrackdirBitsToTrackBits(ft.m_new_td_bits);
    02356       if (enterdir != NULL) *enterdir = ft.m_exitdir;
    02357       return PBSTileInfo(ft.m_new_tile, ft.m_old_td, false);
    02358     }
    02359
    02360     tile = ft.m_new_tile;
    02361     cur_td = FindFirstTrackdir(ft.m_new_td_bits);
    02362
    02363     if (IsSafeWaitingPosition(v, tile, cur_td, true, _settings_game.pf.forbid_90_deg)) {
    02364       bool wp_free = IsWaitingPositionFree(v, tile, cur_td, _settings_game.pf.forbid_90_deg);
    02365       if (!(wp_free && TryReserveRailTrack(tile, TrackdirToTrack(cur_td)))) break;
    02366       /* Safe position is all good, path valid and okay. */
    02367       return PBSTileInfo(tile, cur_td, true);
    02368     }
    02369
    02370     if (!TryReserveRailTrack(tile, TrackdirToTrack(cur_td))) break;
    02371   }
    02372
    02373   if (ft.m_err == CFollowTrackRail::EC_OWNER || ft.m_err == CFollowTrackRail::EC_NO_WAY) {
    02374     /* End of line, path valid and okay. */
    02375     return PBSTileInfo(ft.m_old_tile, ft.m_old_td, true);
    02376   }
    02377
    02378   /* Sorry, can't reserve path, back out. */
    02379   tile = origin.tile;
    02380   cur_td = origin.trackdir;
    02381   TileIndex stopped = ft.m_old_tile;
    02382   Trackdir  stopped_td = ft.m_old_td;
    02383   while (tile != stopped || cur_td != stopped_td) {
    02384     if (!ft.Follow(tile, cur_td)) break;
    02385
    02386     if (_settings_game.pf.forbid_90_deg) {
    02387       ft.m_new_td_bits &= ~TrackdirCrossesTrackdirs(ft.m_old_td);
    02388       assert(ft.m_new_td_bits != TRACKDIR_BIT_NONE);
    02389     }
    02390     assert(KillFirstBit(ft.m_new_td_bits) == TRACKDIR_BIT_NONE);
    02391
    02392     tile = ft.m_new_tile;
    02393     cur_td = FindFirstTrackdir(ft.m_new_td_bits);
    02394
    02395     UnreserveRailTrack(tile, TrackdirToTrack(cur_td));
    02396   }
    02397
    02398   /* Path invalid. */
    02399   return PBSTileInfo();
    02400 }
    02401
    02412 static bool TryReserveSafeTrack(const Train *v, TileIndex tile, Trackdir td, bool override_tailtype)
    02413 {
    02414   switch (_settings_game.pf.pathfinder_for_trains) {
    02415     case VPF_NPF: return NPFTrainFindNearestSafeTile(v, tile, td, override_tailtype);
    02416     case VPF_YAPF: return YapfTrainFindNearestSafeTile(v, tile, td, override_tailtype);
    02417
    02418     default: NOT_REACHED();
    02419   }
    02420 }
    02421
    02423 class VehicleOrderSaver {
    02424 private:
    02425   Train          *v;
    02426   Order          old_order;
    02427   TileIndex      old_dest_tile;
    02428   StationID      old_last_station_visited;
    02429   VehicleOrderID index;
    02430   bool           suppress_implicit_orders;
    02431
    02432 public:
    02433   VehicleOrderSaver(Train *_v) :
    02434     v(_v),
    02435     old_order(_v->current_order),
    02436     old_dest_tile(_v->dest_tile),
    02437     old_last_station_visited(_v->last_station_visited),
    02438     index(_v->cur_real_order_index),
    02439     suppress_implicit_orders(HasBit(_v->gv_flags, GVF_SUPPRESS_IMPLICIT_ORDERS))
    02440   {
    02441   }
    02442
    02443   ~VehicleOrderSaver()
    02444   {
    02445     this->v->current_order = this->old_order;
    02446     this->v->dest_tile = this->old_dest_tile;
    02447     this->v->last_station_visited = this->old_last_station_visited;
    02448     SB(this->v->gv_flags, GVF_SUPPRESS_IMPLICIT_ORDERS, 1, suppress_implicit_orders ? 1: 0);
    02449   }
    02450
    02456   bool SwitchToNextOrder(bool skip_first)
    02457   {
    02458     if (this->v->GetNumOrders() == 0) return false;
    02459
    02460     if (skip_first) ++this->index;
    02461
    02462     int depth = 0;
    02463
    02464     do {
    02465       /* Wrap around. */
    02466       if (this->index >= this->v->GetNumOrders()) this->index = 0;
    02467
    02468       Order *order = this->v->GetOrder(this->index);
    02469       assert(order != NULL);
    02470
    02471       switch (order->GetType()) {
    02472         case OT_GOTO_DEPOT:
    02473           /* Skip service in depot orders when the train doesn't need service. */
    02474           if ((order->GetDepotOrderType() & ODTFB_SERVICE) && !this->v->NeedsServicing()) break;
    02475         case OT_GOTO_STATION:
    02476         case OT_GOTO_WAYPOINT:
    02477           this->v->current_order = *order;
    02478           return UpdateOrderDest(this->v, order, 0, true);
    02479         case OT_CONDITIONAL: {
    02480           VehicleOrderID next = ProcessConditionalOrder(order, this->v);
    02481           if (next != INVALID_VEH_ORDER_ID) {
    02482             depth++;
    02483             this->index = next;
    02484             /* Don't increment next, so no break here. */
    02485             continue;
    02486           }
    02487           break;
    02488         }
    02489         default:
    02490           break;
    02491       }
    02492       /* Don't increment inside the while because otherwise conditional
    02493        * orders can lead to an infinite loop. */
    02494       ++this->index;
    02495       depth++;
    02496     } while (this->index != this->v->cur_real_order_index && depth < this->v->GetNumOrders());
    02497
    02498     return false;
    02499   }
    02500 };
    02501
    02502 /* choose a track */
    02503 static Track ChooseTrainTrack(Train *v, TileIndex tile, DiagDirection enterdir, TrackBits tracks, bool force_res, bool *got_reservation, bool mark_stuck)
    02504 {
    02505   Track best_track = INVALID_TRACK;
    02506   bool do_track_reservation = _settings_game.pf.reserve_paths || force_res;
    02507   bool changed_signal = false;
    02508
    02509   assert((tracks & ~TRACK_BIT_MASK) == 0);
    02510
    02511   if (got_reservation != NULL) *got_reservation = false;
    02512
    02513   /* Don't use tracks here as the setting to forbid 90 deg turns might have been switched between reservation and now. */
    02514   TrackBits res_tracks = (TrackBits)(GetReservedTrackbits(tile) & DiagdirReachesTracks(enterdir));
    02515   /* Do we have a suitable reserved track? */
    02516   if (res_tracks != TRACK_BIT_NONE) return FindFirstTrack(res_tracks);
    02517
    02518   /* Quick return in case only one possible track is available */
    02519   if (KillFirstBit(tracks) == TRACK_BIT_NONE) {
    02520     Track track = FindFirstTrack(tracks);
    02521     /* We need to check for signals only here, as a junction tile can't have signals. */
    02522     if (track != INVALID_TRACK && HasPbsSignalOnTrackdir(tile, TrackEnterdirToTrackdir(track, enterdir))) {
    02523       do_track_reservation = true;
    02524       changed_signal = true;
    02525       SetSignalStateByTrackdir(tile, TrackEnterdirToTrackdir(track, enterdir), SIGNAL_STATE_GREEN);
    02526     } else if (!do_track_reservation) {
    02527       return track;
    02528     }
    02529     best_track = track;
    02530   }
    02531
    02532   PBSTileInfo   res_dest(tile, INVALID_TRACKDIR, false);
    02533   DiagDirection dest_enterdir = enterdir;
    02534   if (do_track_reservation) {
    02535     res_dest = ExtendTrainReservation(v, &tracks, &dest_enterdir);
    02536     if (res_dest.tile == INVALID_TILE) {
    02537       /* Reservation failed? */
    02538       if (mark_stuck) MarkTrainAsStuck(v);
    02539       if (changed_signal) SetSignalStateByTrackdir(tile, TrackEnterdirToTrackdir(best_track, enterdir), SIGNAL_STATE_RED);
    02540       return FindFirstTrack(tracks);
    02541     }
    02542     if (res_dest.okay) {
    02543       /* Got a valid reservation that ends at a safe target, quick exit. */
    02544       if (got_reservation != NULL) *got_reservation = true;
    02545       if (changed_signal) MarkTileDirtyByTile(tile);
    02546       TryReserveRailTrack(v->tile, TrackdirToTrack(v->GetVehicleTrackdir()));
    02547       return best_track;
    02548     }
    02549
    02550     /* Check if the train needs service here, so it has a chance to always find a depot.
    02551      * Also check if the current order is a service order so we don't reserve a path to
    02552      * the destination but instead to the next one if service isn't needed. */
    02553     CheckIfTrainNeedsService(v);
    02554     if (v->current_order.IsType(OT_DUMMY) || v->current_order.IsType(OT_CONDITIONAL) || v->current_order.IsType(OT_GOTO_DEPOT)) ProcessOrders(v);
    02555   }
    02556
    02557   /* Save the current train order. The destructor will restore the old order on function exit. */
    02558   VehicleOrderSaver orders(v);
    02559
    02560   /* If the current tile is the destination of the current order and
    02561    * a reservation was requested, advance to the next order.
    02562    * Don't advance on a depot order as depots are always safe end points
    02563    * for a path and no look-ahead is necessary. This also avoids a
    02564    * problem with depot orders not part of the order list when the
    02565    * order list itself is empty. */
    02566   if (v->current_order.IsType(OT_LEAVESTATION)) {
    02567     orders.SwitchToNextOrder(false);
    02568   } else if (v->current_order.IsType(OT_LOADING) || (!v->current_order.IsType(OT_GOTO_DEPOT) && (
    02569       v->current_order.IsType(OT_GOTO_STATION) ?
    02570       IsRailStationTile(v->tile) && v->current_order.GetDestination() == GetStationIndex(v->tile) :
    02571       v->tile == v->dest_tile))) {
    02572     orders.SwitchToNextOrder(true);
    02573   }
    02574
    02575   if (res_dest.tile != INVALID_TILE && !res_dest.okay) {
    02576     /* Pathfinders are able to tell that route was only 'guessed'. */
    02577     bool      path_found = true;
    02578     TileIndex new_tile = res_dest.tile;
    02579
    02580     Track next_track = DoTrainPathfind(v, new_tile, dest_enterdir, tracks, path_found, do_track_reservation, &res_dest);
    02581     if (new_tile == tile) best_track = next_track;
    02582     v->HandlePathfindingResult(path_found);
    02583   }
    02584
    02585   /* No track reservation requested -> finished. */
    02586   if (!do_track_reservation) return best_track;
    02587
    02588   /* A path was found, but could not be reserved. */
    02589   if (res_dest.tile != INVALID_TILE && !res_dest.okay) {
    02590     if (mark_stuck) MarkTrainAsStuck(v);
    02591     FreeTrainTrackReservation(v);
    02592     return best_track;
    02593   }
    02594
    02595   /* No possible reservation target found, we are probably lost. */
    02596   if (res_dest.tile == INVALID_TILE) {
    02597     /* Try to find any safe destination. */
    02598     PBSTileInfo origin = FollowTrainReservation(v);
    02599     if (TryReserveSafeTrack(v, origin.tile, origin.trackdir, false)) {
    02600       TrackBits res = GetReservedTrackbits(tile) & DiagdirReachesTracks(enterdir);
    02601       best_track = FindFirstTrack(res);
    02602       TryReserveRailTrack(v->tile, TrackdirToTrack(v->GetVehicleTrackdir()));
    02603       if (got_reservation != NULL) *got_reservation = true;
    02604       if (changed_signal) MarkTileDirtyByTile(tile);
    02605     } else {
    02606       FreeTrainTrackReservation(v);
    02607       if (mark_stuck) MarkTrainAsStuck(v);
    02608     }
    02609     return best_track;
    02610   }
    02611
    02612   if (got_reservation != NULL) *got_reservation = true;
    02613
    02614   /* Reservation target found and free, check if it is safe. */
    02615   while (!IsSafeWaitingPosition(v, res_dest.tile, res_dest.trackdir, true, _settings_game.pf.forbid_90_deg)) {
    02616     /* Extend reservation until we have found a safe position. */
    02617     DiagDirection exitdir = TrackdirToExitdir(res_dest.trackdir);
    02618     TileIndex     next_tile = TileAddByDiagDir(res_dest.tile, exitdir);
    02619     TrackBits     reachable = TrackdirBitsToTrackBits((TrackdirBits)(GetTileTrackStatus(next_tile, TRANSPORT_RAIL, 0))) & DiagdirReachesTracks(exitdir);
    02620     if (_settings_game.pf.forbid_90_deg) {
    02621       reachable &= ~TrackCrossesTracks(TrackdirToTrack(res_dest.trackdir));
    02622     }
    02623
    02624     /* Get next order with destination. */
    02625     if (orders.SwitchToNextOrder(true)) {
    02626       PBSTileInfo cur_dest;
    02627       bool path_found;
    02628       DoTrainPathfind(v, next_tile, exitdir, reachable, path_found, true, &cur_dest);
    02629       if (cur_dest.tile != INVALID_TILE) {
    02630         res_dest = cur_dest;
    02631         if (res_dest.okay) continue;
    02632         /* Path found, but could not be reserved. */
    02633         FreeTrainTrackReservation(v);
    02634         if (mark_stuck) MarkTrainAsStuck(v);
    02635         if (got_reservation != NULL) *got_reservation = false;
    02636         changed_signal = false;
    02637         break;
    02638       }
    02639     }
    02640     /* No order or no safe position found, try any position. */
    02641     if (!TryReserveSafeTrack(v, res_dest.tile, res_dest.trackdir, true)) {
    02642       FreeTrainTrackReservation(v);
    02643       if (mark_stuck) MarkTrainAsStuck(v);
    02644       if (got_reservation != NULL) *got_reservation = false;
    02645       changed_signal = false;
    02646     }
    02647     break;
    02648   }
    02649
    02650   TryReserveRailTrack(v->tile, TrackdirToTrack(v->GetVehicleTrackdir()));
    02651
    02652   if (changed_signal) MarkTileDirtyByTile(tile);
    02653
    02654   return best_track;
    02655 }
    02656
    02665 bool TryPathReserve(Train *v, bool mark_as_stuck, bool first_tile_okay)
    02666 {
    02667   assert(v->IsFrontEngine());
    02668
    02669   /* We have to handle depots specially as the track follower won't look
    02670    * at the depot tile itself but starts from the next tile. If we are still
    02671    * inside the depot, a depot reservation can never be ours. */
    02672   if (v->track == TRACK_BIT_DEPOT) {
    02673     if (HasDepotReservation(v->tile)) {
    02674       if (mark_as_stuck) MarkTrainAsStuck(v);
    02675       return false;
    02676     } else {
    02677       /* Depot not reserved, but the next tile might be. */
    02678       TileIndex next_tile = TileAddByDiagDir(v->tile, GetRailDepotDirection(v->tile));
    02679       if (HasReservedTracks(next_tile, DiagdirReachesTracks(GetRailDepotDirection(v->tile)))) return false;
    02680     }
    02681   }
    02682
    02683   Vehicle *other_train = NULL;
    02684   PBSTileInfo origin = FollowTrainReservation(v, &other_train);
    02685   /* The path we are driving on is already blocked by some other train.
    02686    * This can only happen in certain situations when mixing path and
    02687    * block signals or when changing tracks and/or signals.
    02688    * Exit here as doing any further reservations will probably just
    02689    * make matters worse. */
    02690   if (other_train != NULL && other_train->index != v->index) {
    02691     if (mark_as_stuck) MarkTrainAsStuck(v);
    02692     return false;
    02693   }
    02694   /* If we have a reserved path and the path ends at a safe tile, we are finished already. */
    02695   if (origin.okay && (v->tile != origin.tile || first_tile_okay)) {
    02696     /* Can't be stuck then. */
    02697     if (HasBit(v->flags, VRF_TRAIN_STUCK)) SetWindowWidgetDirty(WC_VEHICLE_VIEW, v->index, WID_VV_START_STOP);
    02698     ClrBit(v->flags, VRF_TRAIN_STUCK);
    02699     return true;
    02700   }
    02701
    02702   /* If we are in a depot, tentatively reserve the depot. */
    02703   if (v->track == TRACK_BIT_DEPOT) {
    02704     SetDepotReservation(v->tile, true);
    02705     if (_settings_client.gui.show_track_reservation) MarkTileDirtyByTile(v->tile);
    02706   }
    02707
    02708   DiagDirection exitdir = TrackdirToExitdir(origin.trackdir);
    02709   TileIndex     new_tile = TileAddByDiagDir(origin.tile, exitdir);
    02710   TrackBits     reachable = TrackdirBitsToTrackBits(TrackStatusToTrackdirBits(GetTileTrackStatus(new_tile, TRANSPORT_RAIL, 0)) & DiagdirReachesTrackdirs(exitdir));
    02711
    02712   if (_settings_game.pf.forbid_90_deg) reachable &= ~TrackCrossesTracks(TrackdirToTrack(origin.trackdir));
    02713
    02714   bool res_made = false;
    02715   ChooseTrainTrack(v, new_tile, exitdir, reachable, true, &res_made, mark_as_stuck);
    02716
    02717   if (!res_made) {
    02718     /* Free the depot reservation as well. */
    02719     if (v->track == TRACK_BIT_DEPOT) SetDepotReservation(v->tile, false);
    02720     return false;
    02721   }
    02722
    02723   if (HasBit(v->flags, VRF_TRAIN_STUCK)) {
    02724     v->wait_counter = 0;
    02725     SetWindowWidgetDirty(WC_VEHICLE_VIEW, v->index, WID_VV_START_STOP);
    02726   }
    02727   ClrBit(v->flags, VRF_TRAIN_STUCK);
    02728   return true;
    02729 }
    02730
    02731
    02732 static bool CheckReverseTrain(const Train *v)
    02733 {
    02734   if (_settings_game.difficulty.line_reverse_mode != 0 ||
    02735       v->track == TRACK_BIT_DEPOT || v->track == TRACK_BIT_WORMHOLE ||
    02736       !(v->direction & 1)) {
    02737     return false;
    02738   }
    02739
    02740   assert(v->track != TRACK_BIT_NONE);
    02741
    02742   switch (_settings_game.pf.pathfinder_for_trains) {
    02743     case VPF_NPF: return NPFTrainCheckReverse(v);
    02744     case VPF_YAPF: return YapfTrainCheckReverse(v);
    02745
    02746     default: NOT_REACHED();
    02747   }
    02748 }
    02749
    02755 TileIndex Train::GetOrderStationLocation(StationID station)
    02756 {
    02757   if (station == this->last_station_visited) this->last_station_visited = INVALID_STATION;
    02758
    02759   const Station *st = Station::Get(station);
    02760   if (!(st->facilities & FACIL_TRAIN)) {
    02761     /* The destination station has no trainstation tiles. */
    02762     this->IncrementRealOrderIndex();
    02763     return 0;
    02764   }
    02765
    02766   return st->xy;
    02767 }
    02768
    02770 void Train::MarkDirty()
    02771 {
    02772   Train *v = this;
    02773   do {
    02774     v->colourmap = PAL_NONE;
    02775     v->UpdateViewport(true, false);
    02776   } while ((v = v->Next()) != NULL);
    02777
    02778   /* need to update acceleration and cached values since the goods on the train changed. */
    02779   this->CargoChanged();
    02780   this->UpdateAcceleration();
    02781 }
    02782
    02790 int Train::UpdateSpeed()
    02791 {
    02792   switch (_settings_game.vehicle.train_acceleration_model) {
    02793     default: NOT_REACHED();
    02794     case AM_ORIGINAL:
    02795       return this->DoUpdateSpeed(this->acceleration * (this->GetAccelerationStatus() == AS_BRAKE ? -4 : 2), 0, this->GetCurrentMaxSpeed());
    02796
    02797     case AM_REALISTIC:
    02798       return this->DoUpdateSpeed(this->GetAcceleration(), this->GetAccelerationStatus() == AS_BRAKE ? 0 : 2, this->GetCurrentMaxSpeed());
    02799   }
    02800 }
    02801
    02807 static void TrainEnterStation(Train *v, StationID station)
    02808 {
    02809   v->last_station_visited = station;
    02810
    02811   /* check if a train ever visited this station before */
    02812   Station *st = Station::Get(station);
    02813   if (!(st->had_vehicle_of_type & HVOT_TRAIN)) {
    02814     st->had_vehicle_of_type |= HVOT_TRAIN;
    02815     SetDParam(0, st->index);
    02816     AddVehicleNewsItem(
    02817       STR_NEWS_FIRST_TRAIN_ARRIVAL,
    02818       v->owner == _local_company ? NT_ARRIVAL_COMPANY : NT_ARRIVAL_OTHER,
    02819       v->index,
    02820       st->index
    02821     );
    02822     AI::NewEvent(v->owner, new ScriptEventStationFirstVehicle(st->index, v->index));
    02823     Game::NewEvent(new ScriptEventStationFirstVehicle(st->index, v->index));
    02824   }
    02825
    02826   v->force_proceed = TFP_NONE;
    02827   SetWindowDirty(WC_VEHICLE_VIEW, v->index);
    02828
    02829   v->BeginLoading();
    02830
    02831   TriggerStationRandomisation(st, v->tile, SRT_TRAIN_ARRIVES);
    02832   TriggerStationAnimation(st, v->tile, SAT_TRAIN_ARRIVES);
    02833 }
    02834
    02835 /* Check if the vehicle is compatible with the specified tile */
    02836 static inline bool CheckCompatibleRail(const Train *v, TileIndex tile)
    02837 {
    02838   return IsTileOwner(tile, v->owner) &&
    02839       (!v->IsFrontEngine() || HasBit(v->compatible_railtypes, GetRailType(tile)));
    02840 }
    02841
    02843 struct AccelerationSlowdownParams {
    02844   byte small_turn;
    02845   byte large_turn;
    02846   byte z_up;
    02847   byte z_down;
    02848 };
    02849
    02851 static const AccelerationSlowdownParams _accel_slowdown[] = {
    02852   /* normal accel */
    02853   {256 / 4, 256 / 2, 256 / 4, 2},
    02854   {256 / 4, 256 / 2, 256 / 4, 2},
    02855   {0,       256 / 2, 256 / 4, 2},
    02856 };
    02857
    02863 static inline void AffectSpeedByZChange(Train *v, int old_z)
    02864 {
    02865   if (old_z == v->z_pos || _settings_game.vehicle.train_acceleration_model != AM_ORIGINAL) return;
    02866
    02867   const AccelerationSlowdownParams *asp = &_accel_slowdown[GetRailTypeInfo(v->railtype)->acceleration_type];
    02868
    02869   if (old_z < v->z_pos) {
    02870     v->cur_speed -= (v->cur_speed * asp->z_up >> 8);
    02871   } else {
    02872     uint16 spd = v->cur_speed + asp->z_down;
    02873     if (spd <= v->gcache.cached_max_track_speed) v->cur_speed = spd;
    02874   }
    02875 }
    02876
    02877 static bool TrainMovedChangeSignals(TileIndex tile, DiagDirection dir)
    02878 {
    02879   if (IsTileType(tile, MP_RAILWAY) &&
    02880       GetRailTileType(tile) == RAIL_TILE_SIGNALS) {
    02881     TrackdirBits tracks = TrackBitsToTrackdirBits(GetTrackBits(tile)) & DiagdirReachesTrackdirs(dir);
    02882     Trackdir trackdir = FindFirstTrackdir(tracks);
    02883     if (UpdateSignalsOnSegment(tile,  TrackdirToExitdir(trackdir), GetTileOwner(tile)) == SIGSEG_PBS && HasSignalOnTrackdir(tile, trackdir)) {
    02884       /* A PBS block with a non-PBS signal facing us? */
    02885       if (!IsPbsSignal(GetSignalType(tile, TrackdirToTrack(trackdir)))) return true;
    02886     }
    02887   }
    02888   return false;
    02889 }
    02890
    02892 void Train::ReserveTrackUnderConsist() const
    02893 {
    02894   for (const Train *u = this; u != NULL; u = u->Next()) {
    02895     switch (u->track) {
    02896       case TRACK_BIT_WORMHOLE:
    02897         TryReserveRailTrack(u->tile, DiagDirToDiagTrack(GetTunnelBridgeDirection(u->tile)));
    02898         break;
    02899       case TRACK_BIT_DEPOT:
    02900         break;
    02901       default:
    02902         TryReserveRailTrack(u->tile, TrackBitsToTrack(u->track));
    02903         break;
    02904     }
    02905   }
    02906 }
    02907
    02914 uint Train::Crash(bool flooded)
    02915 {
    02916   uint pass = 0;
    02917   if (this->IsFrontEngine()) {
    02918     pass += 2; // driver
    02919
    02920     /* Remove the reserved path in front of the train if it is not stuck.
    02921      * Also clear all reserved tracks the train is currently on. */
    02922     if (!HasBit(this->flags, VRF_TRAIN_STUCK)) FreeTrainTrackReservation(this);
    02923     for (const Train *v = this; v != NULL; v = v->Next()) {
    02924       ClearPathReservation(v, v->tile, v->GetVehicleTrackdir());
    02925       if (IsTileType(v->tile, MP_TUNNELBRIDGE)) {
    02926         /* ClearPathReservation will not free the wormhole exit
    02927          * if the train has just entered the wormhole. */
    02928         SetTunnelBridgeReservation(GetOtherTunnelBridgeEnd(v->tile), false);
    02929       }
    02930     }
    02931
    02932     /* we may need to update crossing we were approaching,
    02933      * but must be updated after the train has been marked crashed */
    02934     TileIndex crossing = TrainApproachingCrossingTile(this);
    02935     if (crossing != INVALID_TILE) UpdateLevelCrossing(crossing);
    02936
    02937     /* Remove the loading indicators (if any) */
    02938     HideFillingPercent(&this->fill_percent_te_id);
    02939   }
    02940
    02941   pass += this->GroundVehicleBase::Crash(flooded);
    02942
    02943   this->crash_anim_pos = flooded ? 4000 : 1; // max 4440, disappear pretty fast when flooded
    02944   return pass;
    02945 }
    02946
    02953 static uint TrainCrashed(Train *v)
    02954 {
    02955   uint num = 0;
    02956
    02957   /* do not crash train twice */
    02958   if (!(v->vehstatus & VS_CRASHED)) {
    02959     num = v->Crash();
    02960     AI::NewEvent(v->owner, new ScriptEventVehicleCrashed(v->index, v->tile, ScriptEventVehicleCrashed::CRASH_TRAIN));
    02961     Game::NewEvent(new ScriptEventVehicleCrashed(v->index, v->tile, ScriptEventVehicleCrashed::CRASH_TRAIN));
    02962   }
    02963
    02964   /* Try to re-reserve track under already crashed train too.
    02965    * Crash() clears the reservation! */
    02966   v->ReserveTrackUnderConsist();
    02967
    02968   return num;
    02969 }
    02970
    02972 struct TrainCollideChecker {
    02973   Train *v;
    02974   uint num;
    02975 };
    02976
    02983 static Vehicle *FindTrainCollideEnum(Vehicle *v, void *data)
    02984 {
    02985   TrainCollideChecker *tcc = (TrainCollideChecker*)data;
    02986
    02987   /* not a train or in depot */
    02988   if (v->type != VEH_TRAIN || Train::From(v)->track == TRACK_BIT_DEPOT) return NULL;
    02989
    02990   /* do not crash into trains of another company. */
    02991   if (v->owner != tcc->v->owner) return NULL;
    02992
    02993   /* get first vehicle now to make most usual checks faster */
    02994   Train *coll = Train::From(v)->First();
    02995
    02996   /* can't collide with own wagons */
    02997   if (coll == tcc->v) return NULL;
    02998
    02999   int x_diff = v->x_pos - tcc->v->x_pos;
    03000   int y_diff = v->y_pos - tcc->v->y_pos;
    03001
    03002   /* Do fast calculation to check whether trains are not in close vicinity
    03003    * and quickly reject trains distant enough for any collision.
    03004    * Differences are shifted by 7, mapping range [-7 .. 8] into [0 .. 15]
    03005    * Differences are then ORed and then we check for any higher bits */
    03006   uint hash = (y_diff + 7) | (x_diff + 7);
    03007   if (hash & ~15) return NULL;
    03008
    03009   /* Slower check using multiplication */
    03010   int min_diff = (Train::From(v)->gcache.cached_veh_length + 1) / 2 + (tcc->v->gcache.cached_veh_length + 1) / 2 - 1;
    03011   if (x_diff * x_diff + y_diff * y_diff > min_diff * min_diff) return NULL;
    03012
    03013   /* Happens when there is a train under bridge next to bridge head */
    03014   if (abs(v->z_pos - tcc->v->z_pos) > 5) return NULL;
    03015
    03016   /* crash both trains */
    03017   tcc->num += TrainCrashed(tcc->v);
    03018   tcc->num += TrainCrashed(coll);
    03019
    03020   return NULL; // continue searching
    03021 }
    03022
    03030 static bool CheckTrainCollision(Train *v)
    03031 {
    03032   /* can't collide in depot */
    03033   if (v->track == TRACK_BIT_DEPOT) return false;
    03034
    03035   assert(v->track == TRACK_BIT_WORMHOLE || TileVirtXY(v->x_pos, v->y_pos) == v->tile);
    03036
    03037   TrainCollideChecker tcc;
    03038   tcc.v = v;
    03039   tcc.num = 0;
    03040
    03041   /* find colliding vehicles */
    03042   if (v->track == TRACK_BIT_WORMHOLE) {
    03043     FindVehicleOnPos(v->tile, &tcc, FindTrainCollideEnum);
    03044     FindVehicleOnPos(GetOtherTunnelBridgeEnd(v->tile), &tcc, FindTrainCollideEnum);
    03045   } else {
    03046     FindVehicleOnPosXY(v->x_pos, v->y_pos, &tcc, FindTrainCollideEnum);
    03047   }
    03048
    03049   /* any dead -> no crash */
    03050   if (tcc.num == 0) return false;
    03051
    03052   SetDParam(0, tcc.num);
    03053   AddVehicleNewsItem(STR_NEWS_TRAIN_CRASH, NT_ACCIDENT, v->index);
    03054
    03055   ModifyStationRatingAround(v->tile, v->owner, -160, 30);
    03056   if (_settings_client.sound.disaster) SndPlayVehicleFx(SND_13_BIG_CRASH, v);
    03057   return true;
    03058 }
    03059
    03060 static Vehicle *CheckTrainAtSignal(Vehicle *v, void *data)
    03061 {
    03062   if (v->type != VEH_TRAIN || (v->vehstatus & VS_CRASHED)) return NULL;
    03063
    03064   Train *t = Train::From(v);
    03065   DiagDirection exitdir = *(DiagDirection *)data;
    03066
    03067   /* not front engine of a train, inside wormhole or depot, crashed */
    03068   if (!t->IsFrontEngine() || !(t->track & TRACK_BIT_MASK)) return NULL;
    03069
    03070   if (t->cur_speed > 5 || TrainExitDir(t->direction, t->track) != exitdir) return NULL;
    03071
    03072   return t;
    03073 }
    03074
    03082 bool TrainController(Train *v, Vehicle *nomove, bool reverse)
    03083 {
    03084   Train *first = v->First();
    03085   Train *prev;
    03086   bool direction_changed = false; // has direction of any part changed?
    03087
    03088   /* For every vehicle after and including the given vehicle */
    03089   for (prev = v->Previous(); v != nomove; prev = v, v = v->Next()) {
    03090     DiagDirection enterdir = DIAGDIR_BEGIN;
    03091     bool update_signals_crossing = false; // will we update signals or crossing state?
    03092
    03093     GetNewVehiclePosResult gp = GetNewVehiclePos(v);
    03094     if (v->track != TRACK_BIT_WORMHOLE) {
    03095       /* Not inside tunnel */
    03096       if (gp.old_tile == gp.new_tile) {
    03097         /* Staying in the old tile */
    03098         if (v->track == TRACK_BIT_DEPOT) {
    03099           /* Inside depot */
    03100           gp.x = v->x_pos;
    03101           gp.y = v->y_pos;
    03102         } else {
    03103           /* Not inside depot */
    03104
    03105           /* Reverse when we are at the end of the track already, do not move to the new position */
    03106           if (v->IsFrontEngine() && !TrainCheckIfLineEnds(v, reverse)) return false;
    03107
    03108           uint32 r = VehicleEnterTile(v, gp.new_tile, gp.x, gp.y);
    03109           if (HasBit(r, VETS_CANNOT_ENTER)) {
    03110             goto invalid_rail;
    03111           }
    03112           if (HasBit(r, VETS_ENTERED_STATION)) {
    03113             /* The new position is the end of the platform */
    03114             TrainEnterStation(v, r >> VETS_STATION_ID_OFFSET);
    03115           }
    03116         }
    03117       } else {
    03118         /* A new tile is about to be entered. */
    03119
    03120         /* Determine what direction we're entering the new tile from */
    03121         enterdir = DiagdirBetweenTiles(gp.old_tile, gp.new_tile);
    03122         assert(IsValidDiagDirection(enterdir));
    03123
    03124         /* Get the status of the tracks in the new tile and mask
    03125          * away the bits that aren't reachable. */
    03126         TrackStatus ts = GetTileTrackStatus(gp.new_tile, TRANSPORT_RAIL, 0, ReverseDiagDir(enterdir));
    03127         TrackdirBits reachable_trackdirs = DiagdirReachesTrackdirs(enterdir);
    03128
    03129         TrackdirBits trackdirbits = TrackStatusToTrackdirBits(ts) & reachable_trackdirs;
    03130         TrackBits red_signals = TrackdirBitsToTrackBits(TrackStatusToRedSignals(ts) & reachable_trackdirs);
    03131
    03132         TrackBits bits = TrackdirBitsToTrackBits(trackdirbits);
    03133         if (_settings_game.pf.forbid_90_deg && prev == NULL) {
    03134           /* We allow wagons to make 90 deg turns, because forbid_90_deg
    03135            * can be switched on halfway a turn */
    03136           bits &= ~TrackCrossesTracks(FindFirstTrack(v->track));
    03137         }
    03138
    03139         if (bits == TRACK_BIT_NONE) goto invalid_rail;
    03140
    03141         /* Check if the new tile constrains tracks that are compatible
    03142          * with the current train, if not, bail out. */
    03143         if (!CheckCompatibleRail(v, gp.new_tile)) goto invalid_rail;
    03144
    03145         TrackBits chosen_track;
    03146         if (prev == NULL) {
    03147           /* Currently the locomotive is active. Determine which one of the
    03148            * available tracks to choose */
    03149           chosen_track = TrackToTrackBits(ChooseTrainTrack(v, gp.new_tile, enterdir, bits, false, NULL, true));
    03150           assert(chosen_track & (bits | GetReservedTrackbits(gp.new_tile)));
    03151
    03152           if (v->force_proceed != TFP_NONE && IsPlainRailTile(gp.new_tile) && HasSignals(gp.new_tile)) {
    03153             /* For each signal we find decrease the counter by one.
    03154              * We start at two, so the first signal we pass decreases
    03155              * this to one, then if we reach the next signal it is
    03156              * decreased to zero and we won't pass that new signal. */
    03157             Trackdir dir = FindFirstTrackdir(trackdirbits);
    03158             if (HasSignalOnTrackdir(gp.new_tile, dir) ||
    03159                 (HasSignalOnTrackdir(gp.new_tile, ReverseTrackdir(dir)) &&
    03160                 GetSignalType(gp.new_tile, TrackdirToTrack(dir)) != SIGTYPE_PBS)) {
    03161               /* However, we do not want to be stopped by PBS signals
    03162                * entered via the back. */
    03163               v->force_proceed = (v->force_proceed == TFP_SIGNAL) ? TFP_STUCK : TFP_NONE;
    03164               SetWindowDirty(WC_VEHICLE_VIEW, v->index);
    03165             }
    03166           }
    03167
    03168           /* Check if it's a red signal and that force proceed is not clicked. */
    03169           if ((red_signals & chosen_track) && v->force_proceed == TFP_NONE) {
    03170             /* In front of a red signal */
    03171             Trackdir i = FindFirstTrackdir(trackdirbits);
    03172
    03173             /* Don't handle stuck trains here. */
    03174             if (HasBit(v->flags, VRF_TRAIN_STUCK)) return false;
    03175
    03176             if (!HasSignalOnTrackdir(gp.new_tile, ReverseTrackdir(i))) {
    03177               v->cur_speed = 0;
    03178               v->subspeed = 0;
    03179               v->progress = 255 - 100;
    03180               if (!_settings_game.pf.reverse_at_signals || ++v->wait_counter < _settings_game.pf.wait_oneway_signal * 20) return false;
    03181             } else if (HasSignalOnTrackdir(gp.new_tile, i)) {
    03182               v->cur_speed = 0;
    03183               v->subspeed = 0;
    03184               v->progress = 255 - 10;
    03185               if (!_settings_game.pf.reverse_at_signals || ++v->wait_counter < _settings_game.pf.wait_twoway_signal * 73) {
    03186                 DiagDirection exitdir = TrackdirToExitdir(i);
    03187                 TileIndex o_tile = TileAddByDiagDir(gp.new_tile, exitdir);
    03188
    03189                 exitdir = ReverseDiagDir(exitdir);
    03190
    03191                 /* check if a train is waiting on the other side */
    03192                 if (!HasVehicleOnPos(o_tile, &exitdir, &CheckTrainAtSignal)) return false;
    03193               }
    03194             }
    03195
    03196             /* If we would reverse but are currently in a PBS block and
    03197              * reversing of stuck trains is disabled, don't reverse.
    03198              * This does not apply if the reason for reversing is a one-way
    03199              * signal blocking us, because a train would then be stuck forever. */
    03200             if (!_settings_game.pf.reverse_at_signals && !HasOnewaySignalBlockingTrackdir(gp.new_tile, i) &&
    03201                 UpdateSignalsOnSegment(v->tile, enterdir, v->owner) == SIGSEG_PBS) {
    03202               v->wait_counter = 0;
    03203               return false;
    03204             }
    03205             goto reverse_train_direction;
    03206           } else {
    03207             TryReserveRailTrack(gp.new_tile, TrackBitsToTrack(chosen_track), false);
    03208           }
    03209         } else {
    03210           /* The wagon is active, simply follow the prev vehicle. */
    03211           if (prev->tile == gp.new_tile) {
    03212             /* Choose the same track as prev */
    03213             if (prev->track == TRACK_BIT_WORMHOLE) {
    03214               /* Vehicles entering tunnels enter the wormhole earlier than for bridges.
    03215                * However, just choose the track into the wormhole. */
    03216               assert(IsTunnel(prev->tile));
    03217               chosen_track = bits;
    03218             } else {
    03219               chosen_track = prev->track;
    03220             }
    03221           } else {
    03222             /* Choose the track that leads to the tile where prev is.
    03223              * This case is active if 'prev' is already on the second next tile, when 'v' just enters the next tile.
    03224              * I.e. when the tile between them has only space for a single vehicle like
    03225              *  1) horizontal/vertical track tiles and
    03226              *  2) some orientations of tunnel entries, where the vehicle is already inside the wormhole at 8/16 from the tile edge.
    03227              *     Is also the train just reversing, the wagon inside the tunnel is 'on' the tile of the opposite tunnel entry.
    03228              */
    03229             static const TrackBits _connecting_track[DIAGDIR_END][DIAGDIR_END] = {
    03230               {TRACK_BIT_X,     TRACK_BIT_LOWER, TRACK_BIT_NONE,  TRACK_BIT_LEFT },
    03231               {TRACK_BIT_UPPER, TRACK_BIT_Y,     TRACK_BIT_LEFT,  TRACK_BIT_NONE },
    03232               {TRACK_BIT_NONE,  TRACK_BIT_RIGHT, TRACK_BIT_X,     TRACK_BIT_UPPER},
    03233               {TRACK_BIT_RIGHT, TRACK_BIT_NONE,  TRACK_BIT_LOWER, TRACK_BIT_Y    }
    03234             };
    03235             DiagDirection exitdir = DiagdirBetweenTiles(gp.new_tile, prev->tile);
    03236             assert(IsValidDiagDirection(exitdir));
    03237             chosen_track = _connecting_track[enterdir][exitdir];
    03238           }
    03239           chosen_track &= bits;
    03240         }
    03241
    03242         /* Make sure chosen track is a valid track */
    03243         assert(
    03244             chosen_track == TRACK_BIT_X     || chosen_track == TRACK_BIT_Y ||
    03245             chosen_track == TRACK_BIT_UPPER || chosen_track == TRACK_BIT_LOWER ||
    03246             chosen_track == TRACK_BIT_LEFT  || chosen_track == TRACK_BIT_RIGHT);
    03247
    03248         /* Update XY to reflect the entrance to the new tile, and select the direction to use */
    03249         const byte *b = _initial_tile_subcoord[FIND_FIRST_BIT(chosen_track)][enterdir];
    03250         gp.x = (gp.x & ~0xF) | b[0];
    03251         gp.y = (gp.y & ~0xF) | b[1];
    03252         Direction chosen_dir = (Direction)b[2];
    03253
    03254         /* Call the landscape function and tell it that the vehicle entered the tile */
    03255         uint32 r = VehicleEnterTile(v, gp.new_tile, gp.x, gp.y);
    03256         if (HasBit(r, VETS_CANNOT_ENTER)) {
    03257           goto invalid_rail;
    03258         }
    03259
    03260         if (!HasBit(r, VETS_ENTERED_WORMHOLE)) {
    03261           Track track = FindFirstTrack(chosen_track);
    03262           Trackdir tdir = TrackDirectionToTrackdir(track, chosen_dir);
    03263           if (v->IsFrontEngine() && HasPbsSignalOnTrackdir(gp.new_tile, tdir)) {
    03264             SetSignalStateByTrackdir(gp.new_tile, tdir, SIGNAL_STATE_RED);
    03265             MarkTileDirtyByTile(gp.new_tile);
    03266           }
    03267
    03268           /* Clear any track reservation when the last vehicle leaves the tile */
    03269           if (v->Next() == NULL) ClearPathReservation(v, v->tile, v->GetVehicleTrackdir());
    03270
    03271           v->tile = gp.new_tile;
    03272
    03273           if (GetTileRailType(gp.new_tile) != GetTileRailType(gp.old_tile)) {
    03274             v->First()->ConsistChanged(true);
    03275           }
    03276
    03277           v->track = chosen_track;
    03278           assert(v->track);
    03279         }
    03280
    03281         /* We need to update signal status, but after the vehicle position hash
    03282          * has been updated by UpdateInclination() */
    03283         update_signals_crossing = true;
    03284
    03285         if (chosen_dir != v->direction) {
    03286           if (prev == NULL && _settings_game.vehicle.train_acceleration_model == AM_ORIGINAL) {
    03287             const AccelerationSlowdownParams *asp = &_accel_slowdown[GetRailTypeInfo(v->railtype)->acceleration_type];
    03288             DirDiff diff = DirDifference(v->direction, chosen_dir);
    03289             v->cur_speed -= (diff == DIRDIFF_45RIGHT || diff == DIRDIFF_45LEFT ? asp->small_turn : asp->large_turn) * v->cur_speed >> 8;
    03290           }
    03291           direction_changed = true;
    03292           v->direction = chosen_dir;
    03293         }
    03294
    03295         if (v->IsFrontEngine()) {
    03296           v->wait_counter = 0;
    03297
    03298           /* If we are approaching a crossing that is reserved, play the sound now. */
    03299           TileIndex crossing = TrainApproachingCrossingTile(v);
    03300           if (crossing != INVALID_TILE && HasCrossingReservation(crossing) && _settings_client.sound.ambient) SndPlayTileFx(SND_0E_LEVEL_CROSSING, crossing);
    03301
    03302           /* Always try to extend the reservation when entering a tile. */
    03303           CheckNextTrainTile(v);
    03304         }
    03305
    03306         if (HasBit(r, VETS_ENTERED_STATION)) {
    03307           /* The new position is the location where we want to stop */
    03308           TrainEnterStation(v, r >> VETS_STATION_ID_OFFSET);
    03309         }
    03310       }
    03311     } else {
    03312       if (IsTileType(gp.new_tile, MP_TUNNELBRIDGE) && HasBit(VehicleEnterTile(v, gp.new_tile, gp.x, gp.y), VETS_ENTERED_WORMHOLE)) {
    03313         /* Perform look-ahead on tunnel exit. */
    03314         if (v->IsFrontEngine()) {
    03315           TryReserveRailTrack(gp.new_tile, DiagDirToDiagTrack(GetTunnelBridgeDirection(gp.new_tile)));
    03316           CheckNextTrainTile(v);
    03317         }
    03318         /* Prevent v->UpdateInclination() being called with wrong parameters.
    03319          * This could happen if the train was reversed inside the tunnel/bridge. */
    03320         if (gp.old_tile == gp.new_tile) {
    03321           gp.old_tile = GetOtherTunnelBridgeEnd(gp.old_tile);
    03322         }
    03323       } else {
    03324         v->x_pos = gp.x;
    03325         v->y_pos = gp.y;
    03326         VehicleUpdatePosition(v);
    03327         if ((v->vehstatus & VS_HIDDEN) == 0) VehicleUpdateViewport(v, true);
    03328         continue;
    03329       }
    03330     }
    03331
    03332     /* update image of train, as well as delta XY */
    03333     v->UpdateDeltaXY(v->direction);
    03334
    03335     v->x_pos = gp.x;
    03336     v->y_pos = gp.y;
    03337     VehicleUpdatePosition(v);
    03338
    03339     /* update the Z position of the vehicle */
    03340     int old_z = v->UpdateInclination(gp.new_tile != gp.old_tile, false);
    03341
    03342     if (prev == NULL) {
    03343       /* This is the first vehicle in the train */
    03344       AffectSpeedByZChange(v, old_z);
    03345     }
    03346
    03347     if (update_signals_crossing) {
    03348       if (v->IsFrontEngine()) {
    03349         if (TrainMovedChangeSignals(gp.new_tile, enterdir)) {
    03350           /* We are entering a block with PBS signals right now, but
    03351            * not through a PBS signal. This means we don't have a
    03352            * reservation right now. As a conventional signal will only
    03353            * ever be green if no other train is in the block, getting
    03354            * a path should always be possible. If the player built
    03355            * such a strange network that it is not possible, the train
    03356            * will be marked as stuck and the player has to deal with
    03357            * the problem. */
    03358           if ((!HasReservedTracks(gp.new_tile, v->track) &&
    03359               !TryReserveRailTrack(gp.new_tile, FindFirstTrack(v->track))) ||
    03360               !TryPathReserve(v)) {
    03361             MarkTrainAsStuck(v);
    03362           }
    03363         }
    03364       }
    03365
    03366       /* Signals can only change when the first
    03367        * (above) or the last vehicle moves. */
    03368       if (v->Next() == NULL) {
    03369         TrainMovedChangeSignals(gp.old_tile, ReverseDiagDir(enterdir));
    03370         if (IsLevelCrossingTile(gp.old_tile)) UpdateLevelCrossing(gp.old_tile);
    03371       }
    03372     }
    03373
    03374     /* Do not check on every tick to save some computing time. */
    03375     if (v->IsFrontEngine() && v->tick_counter % _settings_game.pf.path_backoff_interval == 0) CheckNextTrainTile(v);
    03376   }
    03377
    03378   if (direction_changed) first->tcache.cached_max_curve_speed = first->GetCurveSpeedLimit();
    03379
    03380   return true;
    03381
    03382 invalid_rail:
    03383   /* We've reached end of line?? */
    03384   if (prev != NULL) error("Disconnecting train");
    03385
    03386 reverse_train_direction:
    03387   if (reverse) {
    03388     v->wait_counter = 0;
    03389     v->cur_speed = 0;
    03390     v->subspeed = 0;
    03391     ReverseTrainDirection(v);
    03392   }
    03393
    03394   return false;
    03395 }
    03396
    03403 static Vehicle *CollectTrackbitsFromCrashedVehiclesEnum(Vehicle *v, void *data)
    03404 {
    03405   TrackBits *trackbits = (TrackBits *)data;
    03406
    03407   if (v->type == VEH_TRAIN && (v->vehstatus & VS_CRASHED) != 0) {
    03408     TrackBits train_tbits = Train::From(v)->track;
    03409     if (train_tbits == TRACK_BIT_WORMHOLE) {
    03410       /* Vehicle is inside a wormhole, v->track contains no useful value then. */
    03411       *trackbits |= DiagDirToDiagTrackBits(GetTunnelBridgeDirection(v->tile));
    03412     } else if (train_tbits != TRACK_BIT_DEPOT) {
    03413       *trackbits |= train_tbits;
    03414     }
    03415   }
    03416
    03417   return NULL;
    03418 }
    03419
    03427 static void DeleteLastWagon(Train *v)
    03428 {
    03429   Train *first = v->First();
    03430
    03431   /* Go to the last wagon and delete the link pointing there
    03432    * *u is then the one-before-last wagon, and *v the last
    03433    * one which will physically be removed */
    03434   Train *u = v;
    03435   for (; v->Next() != NULL; v = v->Next()) u = v;
    03436   u->SetNext(NULL);
    03437
    03438   if (first != v) {
    03439     /* Recalculate cached train properties */
    03440     first->ConsistChanged(false);
    03441     /* Update the depot window if the first vehicle is in depot -
    03442      * if v == first, then it is updated in PreDestructor() */
    03443     if (first->track == TRACK_BIT_DEPOT) {
    03444       SetWindowDirty(WC_VEHICLE_DEPOT, first->tile);
    03445     }
    03446     v->last_station_visited = first->last_station_visited; // for PreDestructor
    03447   }
    03448
    03449   /* 'v' shouldn't be accessed after it has been deleted */
    03450   TrackBits trackbits = v->track;
    03451   TileIndex tile = v->tile;
    03452   Owner owner = v->owner;
    03453
    03454   delete v;
    03455   v = NULL; // make sure nobody will try to read 'v' anymore
    03456
    03457   if (trackbits == TRACK_BIT_WORMHOLE) {
    03458     /* Vehicle is inside a wormhole, v->track contains no useful value then. */
    03459     trackbits = DiagDirToDiagTrackBits(GetTunnelBridgeDirection(tile));
    03460   }
    03461
    03462   Track track = TrackBitsToTrack(trackbits);
    03463   if (HasReservedTracks(tile, trackbits)) {
    03464     UnreserveRailTrack(tile, track);
    03465
    03466     /* If there are still crashed vehicles on the tile, give the track reservation to them */
    03467     TrackBits remaining_trackbits = TRACK_BIT_NONE;
    03468     FindVehicleOnPos(tile, &remaining_trackbits, CollectTrackbitsFromCrashedVehiclesEnum);
    03469
    03470     /* It is important that these two are the first in the loop, as reservation cannot deal with every trackbit combination */
    03471     assert(TRACK_BEGIN == TRACK_X && TRACK_Y == TRACK_BEGIN + 1);
    03472     Track t;
    03473     FOR_EACH_SET_TRACK(t, remaining_trackbits) TryReserveRailTrack(tile, t);
    03474   }
    03475
    03476   /* check if the wagon was on a road/rail-crossing */
    03477   if (IsLevelCrossingTile(tile)) UpdateLevelCrossing(tile);
    03478
    03479   /* Update signals */
    03480   if (IsTileType(tile, MP_TUNNELBRIDGE) || IsRailDepotTile(tile)) {
    03481     UpdateSignalsOnSegment(tile, INVALID_DIAGDIR, owner);
    03482   } else {
    03483     SetSignalsOnBothDir(tile, track, owner);
    03484   }
    03485 }
    03486
    03491 static void ChangeTrainDirRandomly(Train *v)
    03492 {
    03493   static const DirDiff delta[] = {
    03494     DIRDIFF_45LEFT, DIRDIFF_SAME, DIRDIFF_SAME, DIRDIFF_45RIGHT
    03495   };
    03496
    03497   do {
    03498     /* We don't need to twist around vehicles if they're not visible */
    03499     if (!(v->vehstatus & VS_HIDDEN)) {
    03500       v->direction = ChangeDir(v->direction, delta[GB(Random(), 0, 2)]);
    03501       v->UpdateDeltaXY(v->direction);
    03502       v->cur_image = v->GetImage(v->direction, EIT_ON_MAP);
    03503       /* Refrain from updating the z position of the vehicle when on
    03504        * a bridge, because UpdateInclination() will put the vehicle under
    03505        * the bridge in that case */
    03506       if (v->track != TRACK_BIT_WORMHOLE) {
    03507         VehicleUpdatePosition(v);
    03508         v->UpdateInclination(false, false);
    03509       }
    03510     }
    03511   } while ((v = v->Next()) != NULL);
    03512 }
    03513
    03519 static bool HandleCrashedTrain(Train *v)
    03520 {
    03521   int state = ++v->crash_anim_pos;
    03522
    03523   if (state == 4 && !(v->vehstatus & VS_HIDDEN)) {
    03524     CreateEffectVehicleRel(v, 4, 4, 8, EV_EXPLOSION_LARGE);
    03525   }
    03526
    03527   uint32 r;
    03528   if (state <= 200 && Chance16R(1, 7, r)) {
    03529     int index = (r * 10 >> 16);
    03530
    03531     Vehicle *u = v;
    03532     do {
    03533       if (--index < 0) {
    03534         r = Random();
    03535
    03536         CreateEffectVehicleRel(u,
    03537           GB(r,  8, 3) + 2,
    03538           GB(r, 16, 3) + 2,
    03539           GB(r,  0, 3) + 5,
    03540           EV_EXPLOSION_SMALL);
    03541         break;
    03542       }
    03543     } while ((u = u->Next()) != NULL);
    03544   }
    03545
    03546   if (state <= 240 && !(v->tick_counter & 3)) ChangeTrainDirRandomly(v);
    03547
    03548   if (state >= 4440 && !(v->tick_counter & 0x1F)) {
    03549     bool ret = v->Next() != NULL;
    03550     DeleteLastWagon(v);
    03551     return ret;
    03552   }
    03553
    03554   return true;
    03555 }
    03556
    03558 static const uint16 _breakdown_speeds[16] = {
    03559   225, 210, 195, 180, 165, 150, 135, 120, 105, 90, 75, 60, 45, 30, 15, 15
    03560 };
    03561
    03562
    03571 static bool TrainApproachingLineEnd(Train *v, bool signal, bool reverse)
    03572 {
    03573   /* Calc position within the current tile */
    03574   uint x = v->x_pos & 0xF;
    03575   uint y = v->y_pos & 0xF;
    03576
    03577   /* for diagonal directions, 'x' will be 0..15 -
    03578    * for other directions, it will be 1, 3, 5, ..., 15 */
    03579   switch (v->direction) {
    03580     case DIR_N : x = ~x + ~y + 25; break;
    03581     case DIR_NW: x = y;            // FALL THROUGH
    03582     case DIR_NE: x = ~x + 16;      break;
    03583     case DIR_E : x = ~x + y + 9;   break;
    03584     case DIR_SE: x = y;            break;
    03585     case DIR_S : x = x + y - 7;    break;
    03586     case DIR_W : x = ~y + x + 9;   break;
    03587     default: break;
    03588   }
    03589
    03590   /* Do not reverse when approaching red signal. Make sure the vehicle's front
    03591    * does not cross the tile boundary when we do reverse, but as the vehicle's
    03592    * location is based on their center, use half a vehicle's length as offset.
    03593    * Multiply the half-length by two for straight directions to compensate that
    03594    * we only get odd x offsets there. */
    03595   if (!signal && x + (v->gcache.cached_veh_length + 1) / 2 * (IsDiagonalDirection(v->direction) ? 1 : 2) >= TILE_SIZE) {
    03596     /* we are too near the tile end, reverse now */
    03597     v->cur_speed = 0;
    03598     if (reverse) ReverseTrainDirection(v);
    03599     return false;
    03600   }
    03601
    03602   /* slow down */
    03603   v->vehstatus |= VS_TRAIN_SLOWING;
    03604   uint16 break_speed = _breakdown_speeds[x & 0xF];
    03605   if (break_speed < v->cur_speed) v->cur_speed = break_speed;
    03606
    03607   return true;
    03608 }
    03609
    03610
    03616 static bool TrainCanLeaveTile(const Train *v)
    03617 {
    03618   /* Exit if inside a tunnel/bridge or a depot */
    03619   if (v->track == TRACK_BIT_WORMHOLE || v->track == TRACK_BIT_DEPOT) return false;
    03620
    03621   TileIndex tile = v->tile;
    03622
    03623   /* entering a tunnel/bridge? */
    03624   if (IsTileType(tile, MP_TUNNELBRIDGE)) {
    03625     DiagDirection dir = GetTunnelBridgeDirection(tile);
    03626     if (DiagDirToDir(dir) == v->direction) return false;
    03627   }
    03628
    03629   /* entering a depot? */
    03630   if (IsRailDepotTile(tile)) {
    03631     DiagDirection dir = ReverseDiagDir(GetRailDepotDirection(tile));
    03632     if (DiagDirToDir(dir) == v->direction) return false;
    03633   }
    03634
    03635   return true;
    03636 }
    03637
    03638
    03646 static TileIndex TrainApproachingCrossingTile(const Train *v)
    03647 {
    03648   assert(v->IsFrontEngine());
    03649   assert(!(v->vehstatus & VS_CRASHED));
    03650
    03651   if (!TrainCanLeaveTile(v)) return INVALID_TILE;
    03652
    03653   DiagDirection dir = TrainExitDir(v->direction, v->track);
    03654   TileIndex tile = v->tile + TileOffsByDiagDir(dir);
    03655
    03656   /* not a crossing || wrong axis || unusable rail (wrong type or owner) */
    03657   if (!IsLevelCrossingTile(tile) || DiagDirToAxis(dir) == GetCrossingRoadAxis(tile) ||
    03658       !CheckCompatibleRail(v, tile)) {
    03659     return INVALID_TILE;
    03660   }
    03661
    03662   return tile;
    03663 }
    03664
    03665
    03673 static bool TrainCheckIfLineEnds(Train *v, bool reverse)
    03674 {
    03675   /* First, handle broken down train */
    03676
    03677   int t = v->breakdown_ctr;
    03678   if (t > 1) {
    03679     v->vehstatus |= VS_TRAIN_SLOWING;
    03680
    03681     uint16 break_speed = _breakdown_speeds[GB(~t, 4, 4)];
    03682     if (break_speed < v->cur_speed) v->cur_speed = break_speed;
    03683   } else {
    03684     v->vehstatus &= ~VS_TRAIN_SLOWING;
    03685   }
    03686
    03687   if (!TrainCanLeaveTile(v)) return true;
    03688
    03689   /* Determine the non-diagonal direction in which we will exit this tile */
    03690   DiagDirection dir = TrainExitDir(v->direction, v->track);
    03691   /* Calculate next tile */
    03692   TileIndex tile = v->tile + TileOffsByDiagDir(dir);
    03693
    03694   /* Determine the track status on the next tile */
    03695   TrackStatus ts = GetTileTrackStatus(tile, TRANSPORT_RAIL, 0, ReverseDiagDir(dir));
    03696   TrackdirBits reachable_trackdirs = DiagdirReachesTrackdirs(dir);
    03697
    03698   TrackdirBits trackdirbits = TrackStatusToTrackdirBits(ts) & reachable_trackdirs;
    03699   TrackdirBits red_signals = TrackStatusToRedSignals(ts) & reachable_trackdirs;
    03700
    03701   /* We are sure the train is not entering a depot, it is detected above */
    03702
    03703   /* mask unreachable track bits if we are forbidden to do 90deg turns */
    03704   TrackBits bits = TrackdirBitsToTrackBits(trackdirbits);
    03705   if (_settings_game.pf.forbid_90_deg) {
    03706     bits &= ~TrackCrossesTracks(FindFirstTrack(v->track));
    03707   }
    03708
    03709   /* no suitable trackbits at all || unusable rail (wrong type or owner) */
    03710   if (bits == TRACK_BIT_NONE || !CheckCompatibleRail(v, tile)) {
    03711     return TrainApproachingLineEnd(v, false, reverse);
    03712   }
    03713
    03714   /* approaching red signal */
    03715   if ((trackdirbits & red_signals) != 0) return TrainApproachingLineEnd(v, true, reverse);
    03716
    03717   /* approaching a rail/road crossing? then make it red */
    03718   if (IsLevelCrossingTile(tile)) MaybeBarCrossingWithSound(tile);
    03719
    03720   return true;
    03721 }
    03722
    03723
    03724 static bool TrainLocoHandler(Train *v, bool mode)
    03725 {
    03726   /* train has crashed? */
    03727   if (v->vehstatus & VS_CRASHED) {
    03728     return mode ? true : HandleCrashedTrain(v); // 'this' can be deleted here
    03729   }
    03730
    03731   if (v->force_proceed != TFP_NONE) {
    03732     ClrBit(v->flags, VRF_TRAIN_STUCK);
    03733     SetWindowWidgetDirty(WC_VEHICLE_VIEW, v->index, WID_VV_START_STOP);
    03734   }
    03735
    03736   /* train is broken down? */
    03737   if (v->HandleBreakdown()) return true;
    03738
    03739   if (HasBit(v->flags, VRF_REVERSING) && v->cur_speed == 0) {
    03740     ReverseTrainDirection(v);
    03741   }
    03742
    03743   /* exit if train is stopped */
    03744   if ((v->vehstatus & VS_STOPPED) && v->cur_speed == 0) return true;
    03745
    03746   bool valid_order = !v->current_order.IsType(OT_NOTHING) && v->current_order.GetType() != OT_CONDITIONAL;
    03747   if (ProcessOrders(v) && CheckReverseTrain(v)) {
    03748     v->wait_counter = 0;
    03749     v->cur_speed = 0;
    03750     v->subspeed = 0;
    03751     ClrBit(v->flags, VRF_LEAVING_STATION);
    03752     ReverseTrainDirection(v);
    03753     return true;
    03754   } else if (HasBit(v->flags, VRF_LEAVING_STATION)) {
    03755     /* Try to reserve a path when leaving the station as we
    03756      * might not be marked as wanting a reservation, e.g.
    03757      * when an overlength train gets turned around in a station. */
    03758     DiagDirection dir = TrainExitDir(v->direction, v->track);
    03759     if (IsRailDepotTile(v->tile) || IsTileType(v->tile, MP_TUNNELBRIDGE)) dir = INVALID_DIAGDIR;
    03760
    03761     if (UpdateSignalsOnSegment(v->tile, dir, v->owner) == SIGSEG_PBS || _settings_game.pf.reserve_paths) {
    03762       TryPathReserve(v, true, true);
    03763     }
    03764     ClrBit(v->flags, VRF_LEAVING_STATION);
    03765   }
    03766
    03767   v->HandleLoading(mode);
    03768
    03769   if (v->current_order.IsType(OT_LOADING)) return true;
    03770
    03771   if (CheckTrainStayInDepot(v)) return true;
    03772
    03773   if (!mode) v->ShowVisualEffect();
    03774
    03775   /* We had no order but have an order now, do look ahead. */
    03776   if (!valid_order && !v->current_order.IsType(OT_NOTHING)) {
    03777     CheckNextTrainTile(v);
    03778   }
    03779
    03780   /* Handle stuck trains. */
    03781   if (!mode && HasBit(v->flags, VRF_TRAIN_STUCK)) {
    03782     ++v->wait_counter;
    03783
    03784     /* Should we try reversing this tick if still stuck? */
    03785     bool turn_around = v->wait_counter % (_settings_game.pf.wait_for_pbs_path * DAY_TICKS) == 0 && _settings_game.pf.reverse_at_signals;
    03786
    03787     if (!turn_around && v->wait_counter % _settings_game.pf.path_backoff_interval != 0 && v->force_proceed == TFP_NONE) return true;
    03788     if (!TryPathReserve(v)) {
    03789       /* Still stuck. */
    03790       if (turn_around) ReverseTrainDirection(v);
    03791
    03792       if (HasBit(v->flags, VRF_TRAIN_STUCK) && v->wait_counter > 2 * _settings_game.pf.wait_for_pbs_path * DAY_TICKS) {
    03793         /* Show message to player. */
    03794         if (_settings_client.gui.lost_vehicle_warn && v->owner == _local_company) {
    03795           SetDParam(0, v->index);
    03796           AddVehicleAdviceNewsItem(STR_NEWS_TRAIN_IS_STUCK, v->index);
    03797         }
    03798         v->wait_counter = 0;
    03799       }
    03800       /* Exit if force proceed not pressed, else reset stuck flag anyway. */
    03801       if (v->force_proceed == TFP_NONE) return true;
    03802       ClrBit(v->flags, VRF_TRAIN_STUCK);
    03803       v->wait_counter = 0;
    03804       SetWindowWidgetDirty(WC_VEHICLE_VIEW, v->index, WID_VV_START_STOP);
    03805     }
    03806   }
    03807
    03808   if (v->current_order.IsType(OT_LEAVESTATION)) {
    03809     v->current_order.Free();
    03810     SetWindowWidgetDirty(WC_VEHICLE_VIEW, v->index, WID_VV_START_STOP);
    03811     return true;
    03812   }
    03813
    03814   int j = v->UpdateSpeed();
    03815
    03816   /* we need to invalidate the widget if we are stopping from 'Stopping 0 km/h' to 'Stopped' */
    03817   if (v->cur_speed == 0 && (v->vehstatus & VS_STOPPED)) {
    03818     /* If we manually stopped, we're not force-proceeding anymore. */
    03819     v->force_proceed = TFP_NONE;
    03820     SetWindowDirty(WC_VEHICLE_VIEW, v->index);
    03821   }
    03822
    03823   int adv_spd = v->GetAdvanceDistance();
    03824   if (j < adv_spd) {
    03825     /* if the vehicle has speed 0, update the last_speed field. */
    03826     if (v->cur_speed == 0) v->SetLastSpeed();
    03827   } else {
    03828     TrainCheckIfLineEnds(v);
    03829     /* Loop until the train has finished moving. */
    03830     for (;;) {
    03831       j -= adv_spd;
    03832       TrainController(v, NULL);
    03833       /* Don't continue to move if the train crashed. */
    03834       if (CheckTrainCollision(v)) break;
    03835       /* Determine distance to next map position */
    03836       adv_spd = v->GetAdvanceDistance();
    03837
    03838       /* No more moving this tick */
    03839       if (j < adv_spd || v->cur_speed == 0) break;
    03840
    03841       OrderType order_type = v->current_order.GetType();
    03842       /* Do not skip waypoints (incl. 'via' stations) when passing through at full speed. */
    03843       if ((order_type == OT_GOTO_WAYPOINT || order_type == OT_GOTO_STATION) &&
    03844             (v->current_order.GetNonStopType() & ONSF_NO_STOP_AT_DESTINATION_STATION) &&
    03845             IsTileType(v->tile, MP_STATION) &&
    03846             v->current_order.GetDestination() == GetStationIndex(v->tile)) {
    03847         ProcessOrders(v);
    03848       }
    03849     }
    03850     v->SetLastSpeed();
    03851   }
    03852
    03853   for (Train *u = v; u != NULL; u = u->Next()) {
    03854     if ((u->vehstatus & VS_HIDDEN) != 0) continue;
    03855
    03856     u->UpdateViewport(false, false);
    03857   }
    03858
    03859   if (v->progress == 0) v->progress = j; // Save unused spd for next time, if TrainController didn't set progress
    03860
    03861   return true;
    03862 }
    03863
    03868 Money Train::GetRunningCost() const
    03869 {
    03870   Money cost = 0;
    03871   const Train *v = this;
    03872
    03873   do {
    03874     const Engine *e = v->GetEngine();
    03875     if (e->u.rail.running_cost_class == INVALID_PRICE) continue;
    03876
    03877     uint cost_factor = GetVehicleProperty(v, PROP_TRAIN_RUNNING_COST_FACTOR, e->u.rail.running_cost);
    03878     if (cost_factor == 0) continue;
    03879
    03880     /* Halve running cost for multiheaded parts */
    03881     if (v->IsMultiheaded()) cost_factor /= 2;
    03882
    03883     cost += GetPrice(e->u.rail.running_cost_class, cost_factor, e->GetGRF());
    03884   } while ((v = v->GetNextVehicle()) != NULL);
    03885
    03886   return cost;
    03887 }
    03888
    03893 bool Train::Tick()
    03894 {
    03895   this->tick_counter++;
    03896
    03897   if (this->IsFrontEngine()) {
    03898     if (!(this->vehstatus & VS_STOPPED) || this->cur_speed > 0) this->running_ticks++;
    03899
    03900     this->current_order_time++;
    03901
    03902     if (!TrainLocoHandler(this, false)) return false;
    03903
    03904     return TrainLocoHandler(this, true);
    03905   } else if (this->IsFreeWagon() && (this->vehstatus & VS_CRASHED)) {
    03906     /* Delete flooded standalone wagon chain */
    03907     if (++this->crash_anim_pos >= 4400) {
    03908       delete this;
    03909       return false;
    03910     }
    03911   }
    03912
    03913   return true;
    03914 }
    03915
    03920 static void CheckIfTrainNeedsService(Train *v)
    03921 {
    03922   if (Company::Get(v->owner)->settings.vehicle.servint_trains == 0 || !v->NeedsAutomaticServicing()) return;
    03923   if (v->IsChainInDepot()) {
    03924     VehicleServiceInDepot(v);
    03925     return;
    03926   }
    03927
    03928   uint max_penalty;
    03929   switch (_settings_game.pf.pathfinder_for_trains) {
    03930     case VPF_NPF:  max_penalty = _settings_game.pf.npf.maximum_go_to_depot_penalty;  break;
    03931     case VPF_YAPF: max_penalty = _settings_game.pf.yapf.maximum_go_to_depot_penalty; break;
    03932     default: NOT_REACHED();
    03933   }
    03934
    03935   FindDepotData tfdd = FindClosestTrainDepot(v, max_penalty);
    03936   /* Only go to the depot if it is not too far out of our way. */
    03937   if (tfdd.best_length == UINT_MAX || tfdd.best_length > max_penalty) {
    03938     if (v->current_order.IsType(OT_GOTO_DEPOT)) {
    03939       /* If we were already heading for a depot but it has
    03940        * suddenly moved farther away, we continue our normal
    03941        * schedule? */
    03942       v->current_order.MakeDummy();
    03943       SetWindowWidgetDirty(WC_VEHICLE_VIEW, v->index, WID_VV_START_STOP);
    03944     }
    03945     return;
    03946   }
    03947
    03948   DepotID depot = GetDepotIndex(tfdd.tile);
    03949
    03950   if (v->current_order.IsType(OT_GOTO_DEPOT) &&
    03951       v->current_order.GetDestination() != depot &&
    03952       !Chance16(3, 16)) {
    03953     return;
    03954   }
    03955
    03956   SetBit(v->gv_flags, GVF_SUPPRESS_IMPLICIT_ORDERS);
    03957   v->current_order.MakeGoToDepot(depot, ODTFB_SERVICE);
    03958   v->dest_tile = tfdd.tile;
    03959   SetWindowWidgetDirty(WC_VEHICLE_VIEW, v->index, WID_VV_START_STOP);
    03960 }
    03961
    03963 void Train::OnNewDay()
    03964 {
    03965   AgeVehicle(this);
    03966
    03967   if ((++this->day_counter & 7) == 0) DecreaseVehicleValue(this);
    03968
    03969   if (this->IsFrontEngine()) {
    03970     CheckVehicleBreakdown(this);
    03971
    03972     CheckIfTrainNeedsService(this);
    03973
    03974     CheckOrders(this);
    03975
    03976     /* update destination */
    03977     if (this->current_order.IsType(OT_GOTO_STATION)) {
    03978       TileIndex tile = Station::Get(this->current_order.GetDestination())->train_station.tile;
    03979       if (tile != INVALID_TILE) this->dest_tile = tile;
    03980     }
    03981
    03982     if (this->running_ticks != 0) {
    03983       /* running costs */
    03984       CommandCost cost(EXPENSES_TRAIN_RUN, this->GetRunningCost() * this->running_ticks / (DAYS_IN_YEAR  * DAY_TICKS));
    03985
    03986       this->profit_this_year -= cost.GetCost();
    03987       this->running_ticks = 0;
    03988
    03989       SubtractMoneyFromCompanyFract(this->owner, cost);
    03990
    03991       SetWindowDirty(WC_VEHICLE_DETAILS, this->index);
    03992       SetWindowClassesDirty(WC_TRAINS_LIST);
    03993     }
    03994   }
    03995 }
    03996
    04001 Trackdir Train::GetVehicleTrackdir() const
    04002 {
    04003   if (this->vehstatus & VS_CRASHED) return INVALID_TRACKDIR;
    04004
    04005   if (this->track == TRACK_BIT_DEPOT) {
    04006     /* We'll assume the train is facing outwards */
    04007     return DiagDirToDiagTrackdir(GetRailDepotDirection(this->tile)); // Train in depot
    04008   }
    04009
    04010   if (this->track == TRACK_BIT_WORMHOLE) {
    04011     /* train in tunnel or on bridge, so just use his direction and assume a diagonal track */
    04012     return DiagDirToDiagTrackdir(DirToDiagDir(this->direction));
    04013   }
    04014
    04015   return TrackDirectionToTrackdir(FindFirstTrack(this->track), this->direction);
    04016 }