train_cmd.cpp

Go to the documentation of this file.
00001 /* $Id$ */
00002 
00003 /*
00004  * This file is part of OpenTTD.
00005  * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
00006  * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
00007  * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
00008  */
00009 
00012 #include "stdafx.h"
00013 #include "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 
00038 #include "table/strings.h"
00039 #include "table/train_cmd.h"
00040 
00041 static Track ChooseTrainTrack(Train *v, TileIndex tile, DiagDirection enterdir, TrackBits tracks, bool force_res, bool *got_reservation, bool mark_stuck);
00042 static bool TrainCheckIfLineEnds(Train *v, bool reverse = true);
00043 bool TrainController(Train *v, Vehicle *nomove, bool reverse = true); // Also used in vehicle_sl.cpp.
00044 static TileIndex TrainApproachingCrossingTile(const Train *v);
00045 static void CheckIfTrainNeedsService(Train *v);
00046 static void CheckNextTrainTile(Train *v);
00047 
00048 static const byte _vehicle_initial_x_fract[4] = {10, 8, 4,  8};
00049 static const byte _vehicle_initial_y_fract[4] = { 8, 4, 8, 10};
00050 
00051 
00059 static inline DiagDirection TrainExitDir(Direction direction, TrackBits track)
00060 {
00061   static const TrackBits state_dir_table[DIAGDIR_END] = { TRACK_BIT_RIGHT, TRACK_BIT_LOWER, TRACK_BIT_LEFT, TRACK_BIT_UPPER };
00062 
00063   DiagDirection diagdir = DirToDiagDir(direction);
00064 
00065   /* Determine the diagonal direction in which we will exit this tile */
00066   if (!HasBit(direction, 0) && track != state_dir_table[diagdir]) {
00067     diagdir = ChangeDiagDir(diagdir, DIAGDIRDIFF_90LEFT);
00068   }
00069 
00070   return diagdir;
00071 }
00072 
00073 
00079 byte FreightWagonMult(CargoID cargo)
00080 {
00081   if (!CargoSpec::Get(cargo)->is_freight) return 1;
00082   return _settings_game.vehicle.freight_trains;
00083 }
00084 
00086 void CheckTrainsLengths()
00087 {
00088   const Train *v;
00089   bool first = true;
00090 
00091   FOR_ALL_TRAINS(v) {
00092     if (v->First() == v && !(v->vehstatus & VS_CRASHED)) {
00093       for (const Train *u = v, *w = v->Next(); w != NULL; u = w, w = w->Next()) {
00094         if (u->track != TRACK_BIT_DEPOT) {
00095           if ((w->track != TRACK_BIT_DEPOT &&
00096               max(abs(u->x_pos - w->x_pos), abs(u->y_pos - w->y_pos)) != u->CalcNextVehicleOffset()) ||
00097               (w->track == TRACK_BIT_DEPOT && TicksToLeaveDepot(u) <= 0)) {
00098             SetDParam(0, v->index);
00099             SetDParam(1, v->owner);
00100             ShowErrorMessage(STR_BROKEN_VEHICLE_LENGTH, INVALID_STRING_ID, WL_CRITICAL);
00101 
00102             if (!_networking && first) {
00103               first = false;
00104               DoCommandP(0, PM_PAUSED_ERROR, 1, CMD_PAUSE);
00105             }
00106             /* Break so we warn only once for each train. */
00107             break;
00108           }
00109         }
00110       }
00111     }
00112   }
00113 }
00114 
00121 void Train::ConsistChanged(bool same_length)
00122 {
00123   uint16 max_speed = UINT16_MAX;
00124 
00125   assert(this->IsFrontEngine() || this->IsFreeWagon());
00126 
00127   const RailVehicleInfo *rvi_v = RailVehInfo(this->engine_type);
00128   EngineID first_engine = this->IsFrontEngine() ? this->engine_type : INVALID_ENGINE;
00129   this->gcache.cached_total_length = 0;
00130   this->compatible_railtypes = RAILTYPES_NONE;
00131 
00132   bool train_can_tilt = true;
00133 
00134   for (Train *u = this; u != NULL; u = u->Next()) {
00135     const RailVehicleInfo *rvi_u = RailVehInfo(u->engine_type);
00136 
00137     /* Check the this->first cache. */
00138     assert(u->First() == this);
00139 
00140     /* update the 'first engine' */
00141     u->gcache.first_engine = this == u ? INVALID_ENGINE : first_engine;
00142     u->railtype = rvi_u->railtype;
00143 
00144     if (u->IsEngine()) first_engine = u->engine_type;
00145 
00146     /* Set user defined data to its default value */
00147     u->tcache.user_def_data = rvi_u->user_def_data;
00148     this->InvalidateNewGRFCache();
00149     u->InvalidateNewGRFCache();
00150   }
00151 
00152   for (Train *u = this; u != NULL; u = u->Next()) {
00153     /* Update user defined data (must be done before other properties) */
00154     u->tcache.user_def_data = GetVehicleProperty(u, PROP_TRAIN_USER_DATA, u->tcache.user_def_data);
00155     this->InvalidateNewGRFCache();
00156     u->InvalidateNewGRFCache();
00157   }
00158 
00159   for (Train *u = this; u != NULL; u = u->Next()) {
00160     const Engine *e_u = u->GetEngine();
00161     const RailVehicleInfo *rvi_u = &e_u->u.rail;
00162 
00163     if (!HasBit(e_u->info.misc_flags, EF_RAIL_TILTS)) train_can_tilt = false;
00164 
00165     /* Cache wagon override sprite group. NULL is returned if there is none */
00166     u->tcache.cached_override = GetWagonOverrideSpriteSet(u->engine_type, u->cargo_type, u->gcache.first_engine);
00167 
00168     /* Reset colour map */
00169     u->colourmap = PAL_NONE;
00170 
00171     /* Update powered-wagon-status and visual effect */
00172     u->UpdateVisualEffect(true);
00173 
00174     if (rvi_v->pow_wag_power != 0 && rvi_u->railveh_type == RAILVEH_WAGON &&
00175         UsesWagonOverride(u) && !HasBit(u->vcache.cached_vis_effect, VE_DISABLE_WAGON_POWER)) {
00176       /* wagon is powered */
00177       SetBit(u->flags, VRF_POWEREDWAGON); // cache 'powered' status
00178     } else {
00179       ClrBit(u->flags, VRF_POWEREDWAGON);
00180     }
00181 
00182     if (!u->IsArticulatedPart()) {
00183       /* Do not count powered wagons for the compatible railtypes, as wagons always
00184          have railtype normal */
00185       if (rvi_u->power > 0) {
00186         this->compatible_railtypes |= GetRailTypeInfo(u->railtype)->powered_railtypes;
00187       }
00188 
00189       /* Some electric engines can be allowed to run on normal rail. It happens to all
00190        * existing electric engines when elrails are disabled and then re-enabled */
00191       if (HasBit(u->flags, VRF_EL_ENGINE_ALLOWED_NORMAL_RAIL)) {
00192         u->railtype = RAILTYPE_RAIL;
00193         u->compatible_railtypes |= RAILTYPES_RAIL;
00194       }
00195 
00196       /* max speed is the minimum of the speed limits of all vehicles in the consist */
00197       if ((rvi_u->railveh_type != RAILVEH_WAGON || _settings_game.vehicle.wagon_speed_limits) && !UsesWagonOverride(u)) {
00198         uint16 speed = GetVehicleProperty(u, PROP_TRAIN_SPEED, rvi_u->max_speed);
00199         if (speed != 0) max_speed = min(speed, max_speed);
00200       }
00201     }
00202 
00203     uint16 new_cap = e_u->DetermineCapacity(u);
00204     u->refit_cap = min(new_cap, u->refit_cap);
00205     u->cargo_cap = new_cap;
00206     u->vcache.cached_cargo_age_period = GetVehicleProperty(u, PROP_TRAIN_CARGO_AGE_PERIOD, e_u->info.cargo_age_period);
00207 
00208     /* check the vehicle length (callback) */
00209     uint16 veh_len = CALLBACK_FAILED;
00210     if (e_u->GetGRF() != NULL && e_u->GetGRF()->grf_version >= 8) {
00211       /* Use callback 36 */
00212       veh_len = GetVehicleProperty(u, PROP_TRAIN_SHORTEN_FACTOR, CALLBACK_FAILED);
00213 
00214       if (veh_len != CALLBACK_FAILED && veh_len >= VEHICLE_LENGTH) {
00215         ErrorUnknownCallbackResult(e_u->GetGRFID(), CBID_VEHICLE_LENGTH, veh_len);
00216       }
00217     } else if (HasBit(e_u->info.callback_mask, CBM_VEHICLE_LENGTH)) {
00218       /* Use callback 11 */
00219       veh_len = GetVehicleCallback(CBID_VEHICLE_LENGTH, 0, 0, u->engine_type, u);
00220     }
00221     if (veh_len == CALLBACK_FAILED) veh_len = rvi_u->shorten_factor;
00222     veh_len = VEHICLE_LENGTH - Clamp(veh_len, 0, VEHICLE_LENGTH - 1);
00223 
00224     /* verify length hasn't changed */
00225     if (same_length && veh_len != u->gcache.cached_veh_length) VehicleLengthChanged(u);
00226 
00227     /* update vehicle length? */
00228     if (!same_length) u->gcache.cached_veh_length = veh_len;
00229 
00230     this->gcache.cached_total_length += u->gcache.cached_veh_length;
00231     this->InvalidateNewGRFCache();
00232     u->InvalidateNewGRFCache();
00233   }
00234 
00235   /* store consist weight/max speed in cache */
00236   this->vcache.cached_max_speed = max_speed;
00237   this->tcache.cached_tilt = train_can_tilt;
00238   this->tcache.cached_max_curve_speed = this->GetCurveSpeedLimit();
00239 
00240   /* 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) */
00241   this->CargoChanged();
00242 
00243   if (this->IsFrontEngine()) {
00244     this->UpdateAcceleration();
00245     SetWindowDirty(WC_VEHICLE_DETAILS, this->index);
00246     InvalidateWindowData(WC_VEHICLE_REFIT, this->index, VIWD_CONSIST_CHANGED);
00247     InvalidateWindowData(WC_VEHICLE_ORDERS, this->index, VIWD_CONSIST_CHANGED);
00248   }
00249 }
00250 
00261 int GetTrainStopLocation(StationID station_id, TileIndex tile, const Train *v, int *station_ahead, int *station_length)
00262 {
00263   const Station *st = Station::Get(station_id);
00264   *station_ahead  = st->GetPlatformLength(tile, DirToDiagDir(v->direction)) * TILE_SIZE;
00265   *station_length = st->GetPlatformLength(tile) * TILE_SIZE;
00266 
00267   /* Default to the middle of the station for stations stops that are not in
00268    * the order list like intermediate stations when non-stop is disabled */
00269   OrderStopLocation osl = OSL_PLATFORM_MIDDLE;
00270   if (v->gcache.cached_total_length >= *station_length) {
00271     /* The train is longer than the station, make it stop at the far end of the platform */
00272     osl = OSL_PLATFORM_FAR_END;
00273   } else if (v->current_order.IsType(OT_GOTO_STATION) && v->current_order.GetDestination() == station_id) {
00274     osl = v->current_order.GetStopLocation();
00275   }
00276 
00277   /* The stop location of the FRONT! of the train */
00278   int stop;
00279   switch (osl) {
00280     default: NOT_REACHED();
00281 
00282     case OSL_PLATFORM_NEAR_END:
00283       stop = v->gcache.cached_total_length;
00284       break;
00285 
00286     case OSL_PLATFORM_MIDDLE:
00287       stop = *station_length - (*station_length - v->gcache.cached_total_length) / 2;
00288       break;
00289 
00290     case OSL_PLATFORM_FAR_END:
00291       stop = *station_length;
00292       break;
00293   }
00294 
00295   /* Subtract half the front vehicle length of the train so we get the real
00296    * stop location of the train. */
00297   return stop - (v->gcache.cached_veh_length + 1) / 2;
00298 }
00299 
00300 
00305 int Train::GetCurveSpeedLimit() const
00306 {
00307   assert(this->First() == this);
00308 
00309   static const int absolute_max_speed = UINT16_MAX;
00310   int max_speed = absolute_max_speed;
00311 
00312   if (_settings_game.vehicle.train_acceleration_model == AM_ORIGINAL) return max_speed;
00313 
00314   int curvecount[2] = {0, 0};
00315 
00316   /* first find the curve speed limit */
00317   int numcurve = 0;
00318   int sum = 0;
00319   int pos = 0;
00320   int lastpos = -1;
00321   for (const Vehicle *u = this; u->Next() != NULL; u = u->Next(), pos++) {
00322     Direction this_dir = u->direction;
00323     Direction next_dir = u->Next()->direction;
00324 
00325     DirDiff dirdiff = DirDifference(this_dir, next_dir);
00326     if (dirdiff == DIRDIFF_SAME) continue;
00327 
00328     if (dirdiff == DIRDIFF_45LEFT) curvecount[0]++;
00329     if (dirdiff == DIRDIFF_45RIGHT) curvecount[1]++;
00330     if (dirdiff == DIRDIFF_45LEFT || dirdiff == DIRDIFF_45RIGHT) {
00331       if (lastpos != -1) {
00332         numcurve++;
00333         sum += pos - lastpos;
00334         if (pos - lastpos == 1 && max_speed > 88) {
00335           max_speed = 88;
00336         }
00337       }
00338       lastpos = pos;
00339     }
00340 
00341     /* if we have a 90 degree turn, fix the speed limit to 60 */
00342     if (dirdiff == DIRDIFF_90LEFT || dirdiff == DIRDIFF_90RIGHT) {
00343       max_speed = 61;
00344     }
00345   }
00346 
00347   if (numcurve > 0 && max_speed > 88) {
00348     if (curvecount[0] == 1 && curvecount[1] == 1) {
00349       max_speed = absolute_max_speed;
00350     } else {
00351       sum /= numcurve;
00352       max_speed = 232 - (13 - Clamp(sum, 1, 12)) * (13 - Clamp(sum, 1, 12));
00353     }
00354   }
00355 
00356   if (max_speed != absolute_max_speed) {
00357     /* Apply the engine's rail type curve speed advantage, if it slowed by curves */
00358     const RailtypeInfo *rti = GetRailTypeInfo(this->railtype);
00359     max_speed += (max_speed / 2) * rti->curve_speed;
00360 
00361     if (this->tcache.cached_tilt) {
00362       /* Apply max_speed bonus of 20% for a tilting train */
00363       max_speed += max_speed / 5;
00364     }
00365   }
00366 
00367   return max_speed;
00368 }
00369 
00374 int Train::GetCurrentMaxSpeed() const
00375 {
00376   if (_settings_game.vehicle.train_acceleration_model == AM_ORIGINAL) return min(this->gcache.cached_max_track_speed, this->current_order.max_speed);
00377 
00378   int max_speed = this->tcache.cached_max_curve_speed;
00379   if (IsRailStationTile(this->tile)) {
00380     StationID sid = GetStationIndex(this->tile);
00381     if (this->current_order.ShouldStopAtStation(this, sid)) {
00382       int station_ahead;
00383       int station_length;
00384       int stop_at = GetTrainStopLocation(sid, this->tile, this, &station_ahead, &station_length);
00385 
00386       /* The distance to go is whatever is still ahead of the train minus the
00387        * distance from the train's stop location to the end of the platform */
00388       int distance_to_go = station_ahead / TILE_SIZE - (station_length - stop_at) / TILE_SIZE;
00389 
00390       if (distance_to_go > 0) {
00391         int st_max_speed = 120;
00392 
00393         int delta_v = this->cur_speed / (distance_to_go + 1);
00394         if (max_speed > (this->cur_speed - delta_v)) {
00395           st_max_speed = this->cur_speed - (delta_v / 10);
00396         }
00397 
00398         st_max_speed = max(st_max_speed, 25 * distance_to_go);
00399         max_speed = min(max_speed, st_max_speed);
00400       }
00401     }
00402   }
00403 
00404   for (const Train *u = this; u != NULL; u = u->Next()) {
00405     if (u->track == TRACK_BIT_DEPOT) {
00406       max_speed = min(max_speed, 61);
00407       break;
00408     }
00409 
00410     /* Vehicle is on the middle part of a bridge. */
00411     if (u->track == TRACK_BIT_WORMHOLE && !(u->vehstatus & VS_HIDDEN)) {
00412       max_speed = min(max_speed, GetBridgeSpec(GetBridgeType(u->tile))->speed);
00413     }
00414   }
00415 
00416   max_speed = min(max_speed, this->current_order.max_speed);
00417   return min(max_speed, this->gcache.cached_max_track_speed);
00418 }
00419 
00421 void Train::UpdateAcceleration()
00422 {
00423   assert(this->IsFrontEngine());
00424 
00425   uint power = this->gcache.cached_power;
00426   uint weight = this->gcache.cached_weight;
00427   assert(weight != 0);
00428   this->acceleration = Clamp(power / weight * 4, 1, 255);
00429 }
00430 
00436 int Train::GetDisplayImageWidth(Point *offset) const
00437 {
00438   int reference_width = TRAININFO_DEFAULT_VEHICLE_WIDTH;
00439   int vehicle_pitch = 0;
00440 
00441   const Engine *e = this->GetEngine();
00442   if (e->GetGRF() != NULL && is_custom_sprite(e->u.rail.image_index)) {
00443     reference_width = e->GetGRF()->traininfo_vehicle_width;
00444     vehicle_pitch = e->GetGRF()->traininfo_vehicle_pitch;
00445   }
00446 
00447   if (offset != NULL) {
00448     offset->x = reference_width / 2;
00449     offset->y = vehicle_pitch;
00450   }
00451   return this->gcache.cached_veh_length * reference_width / VEHICLE_LENGTH;
00452 }
00453 
00454 static SpriteID GetDefaultTrainSprite(uint8 spritenum, Direction direction)
00455 {
00456   return ((direction + _engine_sprite_add[spritenum]) & _engine_sprite_and[spritenum]) + _engine_sprite_base[spritenum];
00457 }
00458 
00465 SpriteID Train::GetImage(Direction direction, EngineImageType image_type) const
00466 {
00467   uint8 spritenum = this->spritenum;
00468   SpriteID sprite;
00469 
00470   if (HasBit(this->flags, VRF_REVERSE_DIRECTION)) direction = ReverseDir(direction);
00471 
00472   if (is_custom_sprite(spritenum)) {
00473     sprite = GetCustomVehicleSprite(this, (Direction)(direction + 4 * IS_CUSTOM_SECONDHEAD_SPRITE(spritenum)), image_type);
00474     if (sprite != 0) return sprite;
00475 
00476     spritenum = this->GetEngine()->original_image_index;
00477   }
00478 
00479   sprite = GetDefaultTrainSprite(spritenum, direction);
00480 
00481   if (this->cargo.Count() >= this->cargo_cap / 2U) sprite += _wagon_full_adder[spritenum];
00482 
00483   return sprite;
00484 }
00485 
00486 static SpriteID GetRailIcon(EngineID engine, bool rear_head, int &y, EngineImageType image_type)
00487 {
00488   const Engine *e = Engine::Get(engine);
00489   Direction dir = rear_head ? DIR_E : DIR_W;
00490   uint8 spritenum = e->u.rail.image_index;
00491 
00492   if (is_custom_sprite(spritenum)) {
00493     SpriteID sprite = GetCustomVehicleIcon(engine, dir, image_type);
00494     if (sprite != 0) {
00495       if (e->GetGRF() != NULL) {
00496         y += e->GetGRF()->traininfo_vehicle_pitch;
00497       }
00498       return sprite;
00499     }
00500 
00501     spritenum = Engine::Get(engine)->original_image_index;
00502   }
00503 
00504   if (rear_head) spritenum++;
00505 
00506   return GetDefaultTrainSprite(spritenum, DIR_W);
00507 }
00508 
00509 void DrawTrainEngine(int left, int right, int preferred_x, int y, EngineID engine, PaletteID pal, EngineImageType image_type)
00510 {
00511   if (RailVehInfo(engine)->railveh_type == RAILVEH_MULTIHEAD) {
00512     int yf = y;
00513     int yr = y;
00514 
00515     SpriteID spritef = GetRailIcon(engine, false, yf, image_type);
00516     SpriteID spriter = GetRailIcon(engine, true, yr, image_type);
00517     const Sprite *real_spritef = GetSprite(spritef, ST_NORMAL);
00518     const Sprite *real_spriter = GetSprite(spriter, ST_NORMAL);
00519 
00520     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);
00521 
00522     DrawSprite(spritef, pal, preferred_x - 14, yf);
00523     DrawSprite(spriter, pal, preferred_x + 15, yr);
00524   } else {
00525     SpriteID sprite = GetRailIcon(engine, false, y, image_type);
00526     const Sprite *real_sprite = GetSprite(sprite, ST_NORMAL);
00527     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));
00528     DrawSprite(sprite, pal, preferred_x, y);
00529   }
00530 }
00531 
00541 void GetTrainSpriteSize(EngineID engine, uint &width, uint &height, int &xoffs, int &yoffs, EngineImageType image_type)
00542 {
00543   int y = 0;
00544 
00545   SpriteID sprite = GetRailIcon(engine, false, y, image_type);
00546   const Sprite *real_sprite = GetSprite(sprite, ST_NORMAL);
00547 
00548   width  = UnScaleByZoom(real_sprite->width, ZOOM_LVL_GUI);
00549   height = UnScaleByZoom(real_sprite->height, ZOOM_LVL_GUI);
00550   xoffs  = UnScaleByZoom(real_sprite->x_offs, ZOOM_LVL_GUI);
00551   yoffs  = UnScaleByZoom(real_sprite->y_offs, ZOOM_LVL_GUI);
00552 
00553   if (RailVehInfo(engine)->railveh_type == RAILVEH_MULTIHEAD) {
00554     sprite = GetRailIcon(engine, true, y, image_type);
00555     real_sprite = GetSprite(sprite, ST_NORMAL);
00556 
00557     /* Calculate values relative to an imaginary center between the two sprites. */
00558     width = TRAININFO_DEFAULT_VEHICLE_WIDTH + UnScaleByZoom(real_sprite->width, ZOOM_LVL_GUI) + UnScaleByZoom(real_sprite->x_offs, ZOOM_LVL_GUI) - xoffs;
00559     height = max<uint>(height, UnScaleByZoom(real_sprite->height, ZOOM_LVL_GUI));
00560     xoffs  = xoffs - TRAININFO_DEFAULT_VEHICLE_WIDTH / 2;
00561     yoffs  = min(yoffs, UnScaleByZoom(real_sprite->y_offs, ZOOM_LVL_GUI));
00562   }
00563 }
00564 
00573 static CommandCost CmdBuildRailWagon(TileIndex tile, DoCommandFlag flags, const Engine *e, Vehicle **ret)
00574 {
00575   const RailVehicleInfo *rvi = &e->u.rail;
00576 
00577   /* Check that the wagon can drive on the track in question */
00578   if (!IsCompatibleRail(rvi->railtype, GetRailType(tile))) return CMD_ERROR;
00579 
00580   if (flags & DC_EXEC) {
00581     Train *v = new Train();
00582     *ret = v;
00583     v->spritenum = rvi->image_index;
00584 
00585     v->engine_type = e->index;
00586     v->gcache.first_engine = INVALID_ENGINE; // needs to be set before first callback
00587 
00588     DiagDirection dir = GetRailDepotDirection(tile);
00589 
00590     v->direction = DiagDirToDir(dir);
00591     v->tile = tile;
00592 
00593     int x = TileX(tile) * TILE_SIZE | _vehicle_initial_x_fract[dir];
00594     int y = TileY(tile) * TILE_SIZE | _vehicle_initial_y_fract[dir];
00595 
00596     v->x_pos = x;
00597     v->y_pos = y;
00598     v->z_pos = GetSlopePixelZ(x, y);
00599     v->owner = _current_company;
00600     v->track = TRACK_BIT_DEPOT;
00601     v->vehstatus = VS_HIDDEN | VS_DEFPAL;
00602 
00603     v->SetWagon();
00604 
00605     v->SetFreeWagon();
00606     InvalidateWindowData(WC_VEHICLE_DEPOT, v->tile);
00607 
00608     v->cargo_type = e->GetDefaultCargoType();
00609     v->cargo_cap = rvi->capacity;
00610     v->refit_cap = 0;
00611 
00612     v->railtype = rvi->railtype;
00613 
00614     v->build_year = _cur_year;
00615     v->cur_image = SPR_IMG_QUERY;
00616     v->random_bits = VehicleRandomBits();
00617 
00618     v->group_id = DEFAULT_GROUP;
00619 
00620     AddArticulatedParts(v);
00621 
00622     _new_vehicle_id = v->index;
00623 
00624     VehicleUpdatePosition(v);
00625     v->First()->ConsistChanged(false);
00626     UpdateTrainGroupID(v->First());
00627 
00628     CheckConsistencyOfArticulatedVehicle(v);
00629 
00630     /* Try to connect the vehicle to one of free chains of wagons. */
00631     Train *w;
00632     FOR_ALL_TRAINS(w) {
00633       if (w->tile == tile &&              
00634           w->IsFreeWagon() &&             
00635           w->engine_type == e->index &&   
00636           w->First() != v &&              
00637           !(w->vehstatus & VS_CRASHED)) { 
00638         DoCommand(0, v->index | 1 << 20, w->Last()->index, DC_EXEC, CMD_MOVE_RAIL_VEHICLE);
00639         break;
00640       }
00641     }
00642   }
00643 
00644   return CommandCost();
00645 }
00646 
00648 static void NormalizeTrainVehInDepot(const Train *u)
00649 {
00650   const Train *v;
00651   FOR_ALL_TRAINS(v) {
00652     if (v->IsFreeWagon() && v->tile == u->tile &&
00653         v->track == TRACK_BIT_DEPOT) {
00654       if (DoCommand(0, v->index | 1 << 20, u->index, DC_EXEC,
00655           CMD_MOVE_RAIL_VEHICLE).Failed())
00656         break;
00657     }
00658   }
00659 }
00660 
00661 static void AddRearEngineToMultiheadedTrain(Train *v)
00662 {
00663   Train *u = new Train();
00664   v->value >>= 1;
00665   u->value = v->value;
00666   u->direction = v->direction;
00667   u->owner = v->owner;
00668   u->tile = v->tile;
00669   u->x_pos = v->x_pos;
00670   u->y_pos = v->y_pos;
00671   u->z_pos = v->z_pos;
00672   u->track = TRACK_BIT_DEPOT;
00673   u->vehstatus = v->vehstatus & ~VS_STOPPED;
00674   u->spritenum = v->spritenum + 1;
00675   u->cargo_type = v->cargo_type;
00676   u->cargo_subtype = v->cargo_subtype;
00677   u->cargo_cap = v->cargo_cap;
00678   u->refit_cap = v->refit_cap;
00679   u->railtype = v->railtype;
00680   u->engine_type = v->engine_type;
00681   u->build_year = v->build_year;
00682   u->cur_image = SPR_IMG_QUERY;
00683   u->random_bits = VehicleRandomBits();
00684   v->SetMultiheaded();
00685   u->SetMultiheaded();
00686   v->SetNext(u);
00687   VehicleUpdatePosition(u);
00688 
00689   /* Now we need to link the front and rear engines together */
00690   v->other_multiheaded_part = u;
00691   u->other_multiheaded_part = v;
00692 }
00693 
00703 CommandCost CmdBuildRailVehicle(TileIndex tile, DoCommandFlag flags, const Engine *e, uint16 data, Vehicle **ret)
00704 {
00705   const RailVehicleInfo *rvi = &e->u.rail;
00706 
00707   if (rvi->railveh_type == RAILVEH_WAGON) return CmdBuildRailWagon(tile, flags, e, ret);
00708 
00709   /* Check if depot and new engine uses the same kind of tracks *
00710    * We need to see if the engine got power on the tile to avoid electric engines in non-electric depots */
00711   if (!HasPowerOnRail(rvi->railtype, GetRailType(tile))) return CMD_ERROR;
00712 
00713   if (flags & DC_EXEC) {
00714     DiagDirection dir = GetRailDepotDirection(tile);
00715     int x = TileX(tile) * TILE_SIZE + _vehicle_initial_x_fract[dir];
00716     int y = TileY(tile) * TILE_SIZE + _vehicle_initial_y_fract[dir];
00717 
00718     Train *v = new Train();
00719     *ret = v;
00720     v->direction = DiagDirToDir(dir);
00721     v->tile = tile;
00722     v->owner = _current_company;
00723     v->x_pos = x;
00724     v->y_pos = y;
00725     v->z_pos = GetSlopePixelZ(x, y);
00726     v->track = TRACK_BIT_DEPOT;
00727     v->vehstatus = VS_HIDDEN | VS_STOPPED | VS_DEFPAL;
00728     v->spritenum = rvi->image_index;
00729     v->cargo_type = e->GetDefaultCargoType();
00730     v->cargo_cap = rvi->capacity;
00731     v->refit_cap = 0;
00732     v->last_station_visited = INVALID_STATION;
00733     v->last_loading_station = INVALID_STATION;
00734 
00735     v->engine_type = e->index;
00736     v->gcache.first_engine = INVALID_ENGINE; // needs to be set before first callback
00737 
00738     v->reliability = e->reliability;
00739     v->reliability_spd_dec = e->reliability_spd_dec;
00740     v->max_age = e->GetLifeLengthInDays();
00741 
00742     v->railtype = rvi->railtype;
00743     _new_vehicle_id = v->index;
00744 
00745     v->SetServiceInterval(Company::Get(_current_company)->settings.vehicle.servint_trains);
00746     v->date_of_last_service = _date;
00747     v->build_year = _cur_year;
00748     v->cur_image = SPR_IMG_QUERY;
00749     v->random_bits = VehicleRandomBits();
00750 
00751     if (e->flags & ENGINE_EXCLUSIVE_PREVIEW) SetBit(v->vehicle_flags, VF_BUILT_AS_PROTOTYPE);
00752     v->SetServiceIntervalIsPercent(Company::Get(_current_company)->settings.vehicle.servint_ispercent);
00753 
00754     v->group_id = DEFAULT_GROUP;
00755 
00756     v->SetFrontEngine();
00757     v->SetEngine();
00758 
00759     VehicleUpdatePosition(v);
00760 
00761     if (rvi->railveh_type == RAILVEH_MULTIHEAD) {
00762       AddRearEngineToMultiheadedTrain(v);
00763     } else {
00764       AddArticulatedParts(v);
00765     }
00766 
00767     v->ConsistChanged(false);
00768     UpdateTrainGroupID(v);
00769 
00770     if (!HasBit(data, 0) && !(flags & DC_AUTOREPLACE)) { // check if the cars should be added to the new vehicle
00771       NormalizeTrainVehInDepot(v);
00772     }
00773 
00774     CheckConsistencyOfArticulatedVehicle(v);
00775   }
00776 
00777   return CommandCost();
00778 }
00779 
00780 static Train *FindGoodVehiclePos(const Train *src)
00781 {
00782   EngineID eng = src->engine_type;
00783   TileIndex tile = src->tile;
00784 
00785   Train *dst;
00786   FOR_ALL_TRAINS(dst) {
00787     if (dst->IsFreeWagon() && dst->tile == tile && !(dst->vehstatus & VS_CRASHED)) {
00788       /* check so all vehicles in the line have the same engine. */
00789       Train *t = dst;
00790       while (t->engine_type == eng) {
00791         t = t->Next();
00792         if (t == NULL) return dst;
00793       }
00794     }
00795   }
00796 
00797   return NULL;
00798 }
00799 
00801 typedef SmallVector<Train *, 16> TrainList;
00802 
00808 static void MakeTrainBackup(TrainList &list, Train *t)
00809 {
00810   for (; t != NULL; t = t->Next()) *list.Append() = t;
00811 }
00812 
00817 static void RestoreTrainBackup(TrainList &list)
00818 {
00819   /* No train, nothing to do. */
00820   if (list.Length() == 0) return;
00821 
00822   Train *prev = NULL;
00823   /* Iterate over the list and rebuild it. */
00824   for (Train **iter = list.Begin(); iter != list.End(); iter++) {
00825     Train *t = *iter;
00826     if (prev != NULL) {
00827       prev->SetNext(t);
00828     } else if (t->Previous() != NULL) {
00829       /* Make sure the head of the train is always the first in the chain. */
00830       t->Previous()->SetNext(NULL);
00831     }
00832     prev = t;
00833   }
00834 }
00835 
00841 static void RemoveFromConsist(Train *part, bool chain = false)
00842 {
00843   Train *tail = chain ? part->Last() : part->GetLastEnginePart();
00844 
00845   /* Unlink at the front, but make it point to the next
00846    * vehicle after the to be remove part. */
00847   if (part->Previous() != NULL) part->Previous()->SetNext(tail->Next());
00848 
00849   /* Unlink at the back */
00850   tail->SetNext(NULL);
00851 }
00852 
00858 static void InsertInConsist(Train *dst, Train *chain)
00859 {
00860   /* We do not want to add something in the middle of an articulated part. */
00861   assert(dst->Next() == NULL || !dst->Next()->IsArticulatedPart());
00862 
00863   chain->Last()->SetNext(dst->Next());
00864   dst->SetNext(chain);
00865 }
00866 
00872 static void NormaliseDualHeads(Train *t)
00873 {
00874   for (; t != NULL; t = t->GetNextVehicle()) {
00875     if (!t->IsMultiheaded() || !t->IsEngine()) continue;
00876 
00877     /* Make sure that there are no free cars before next engine */
00878     Train *u;
00879     for (u = t; u->Next() != NULL && !u->Next()->IsEngine(); u = u->Next()) {}
00880 
00881     if (u == t->other_multiheaded_part) continue;
00882 
00883     /* Remove the part from the 'wrong' train */
00884     RemoveFromConsist(t->other_multiheaded_part);
00885     /* And add it to the 'right' train */
00886     InsertInConsist(u, t->other_multiheaded_part);
00887   }
00888 }
00889 
00894 static void NormaliseSubtypes(Train *chain)
00895 {
00896   /* Nothing to do */
00897   if (chain == NULL) return;
00898 
00899   /* We must be the first in the chain. */
00900   assert(chain->Previous() == NULL);
00901 
00902   /* Set the appropriate bits for the first in the chain. */
00903   if (chain->IsWagon()) {
00904     chain->SetFreeWagon();
00905   } else {
00906     assert(chain->IsEngine());
00907     chain->SetFrontEngine();
00908   }
00909 
00910   /* Now clear the bits for the rest of the chain */
00911   for (Train *t = chain->Next(); t != NULL; t = t->Next()) {
00912     t->ClearFreeWagon();
00913     t->ClearFrontEngine();
00914   }
00915 }
00916 
00926 static CommandCost CheckNewTrain(Train *original_dst, Train *dst, Train *original_src, Train *src)
00927 {
00928   /* Just add 'new' engines and subtract the original ones.
00929    * If that's less than or equal to 0 we can be sure we did
00930    * not add any engines (read: trains) along the way. */
00931   if ((src          != NULL && src->IsEngine()          ? 1 : 0) +
00932       (dst          != NULL && dst->IsEngine()          ? 1 : 0) -
00933       (original_src != NULL && original_src->IsEngine() ? 1 : 0) -
00934       (original_dst != NULL && original_dst->IsEngine() ? 1 : 0) <= 0) {
00935     return CommandCost();
00936   }
00937 
00938   /* Get a free unit number and check whether it's within the bounds.
00939    * There will always be a maximum of one new train. */
00940   if (GetFreeUnitNumber(VEH_TRAIN) <= _settings_game.vehicle.max_trains) return CommandCost();
00941 
00942   return_cmd_error(STR_ERROR_TOO_MANY_VEHICLES_IN_GAME);
00943 }
00944 
00950 static CommandCost CheckTrainAttachment(Train *t)
00951 {
00952   /* No multi-part train, no need to check. */
00953   if (t == NULL || t->Next() == NULL || !t->IsEngine()) return CommandCost();
00954 
00955   /* The maximum length for a train. For each part we decrease this by one
00956    * and if the result is negative the train is simply too long. */
00957   int allowed_len = _settings_game.vehicle.max_train_length * TILE_SIZE - t->gcache.cached_veh_length;
00958 
00959   Train *head = t;
00960   Train *prev = t;
00961 
00962   /* Break the prev -> t link so it always holds within the loop. */
00963   t = t->Next();
00964   prev->SetNext(NULL);
00965 
00966   /* Make sure the cache is cleared. */
00967   head->InvalidateNewGRFCache();
00968 
00969   while (t != NULL) {
00970     allowed_len -= t->gcache.cached_veh_length;
00971 
00972     Train *next = t->Next();
00973 
00974     /* Unlink the to-be-added piece; it is already unlinked from the previous
00975      * part due to the fact that the prev -> t link is broken. */
00976     t->SetNext(NULL);
00977 
00978     /* Don't check callback for articulated or rear dual headed parts */
00979     if (!t->IsArticulatedPart() && !t->IsRearDualheaded()) {
00980       /* Back up and clear the first_engine data to avoid using wagon override group */
00981       EngineID first_engine = t->gcache.first_engine;
00982       t->gcache.first_engine = INVALID_ENGINE;
00983 
00984       /* We don't want the cache to interfere. head's cache is cleared before
00985        * the loop and after each callback does not need to be cleared here. */
00986       t->InvalidateNewGRFCache();
00987 
00988       uint16 callback = GetVehicleCallbackParent(CBID_TRAIN_ALLOW_WAGON_ATTACH, 0, 0, head->engine_type, t, head);
00989 
00990       /* Restore original first_engine data */
00991       t->gcache.first_engine = first_engine;
00992 
00993       /* We do not want to remember any cached variables from the test run */
00994       t->InvalidateNewGRFCache();
00995       head->InvalidateNewGRFCache();
00996 
00997       if (callback != CALLBACK_FAILED) {
00998         /* A failing callback means everything is okay */
00999         StringID error = STR_NULL;
01000 
01001         if (head->GetGRF()->grf_version < 8) {
01002           if (callback == 0xFD) error = STR_ERROR_INCOMPATIBLE_RAIL_TYPES;
01003           if (callback  < 0xFD) error = GetGRFStringID(head->GetGRFID(), 0xD000 + callback);
01004           if (callback >= 0x100) ErrorUnknownCallbackResult(head->GetGRFID(), CBID_TRAIN_ALLOW_WAGON_ATTACH, callback);
01005         } else {
01006           if (callback < 0x400) {
01007             error = GetGRFStringID(head->GetGRFID(), 0xD000 + callback);
01008           } else {
01009             switch (callback) {
01010               case 0x400: // allow if railtypes match (always the case for OpenTTD)
01011               case 0x401: // allow
01012                 break;
01013 
01014               default:    // unknown reason -> disallow
01015               case 0x402: // disallow attaching
01016                 error = STR_ERROR_INCOMPATIBLE_RAIL_TYPES;
01017                 break;
01018             }
01019           }
01020         }
01021 
01022         if (error != STR_NULL) return_cmd_error(error);
01023       }
01024     }
01025 
01026     /* And link it to the new part. */
01027     prev->SetNext(t);
01028     prev = t;
01029     t = next;
01030   }
01031 
01032   if (allowed_len < 0) return_cmd_error(STR_ERROR_TRAIN_TOO_LONG);
01033   return CommandCost();
01034 }
01035 
01046 static CommandCost ValidateTrains(Train *original_dst, Train *dst, Train *original_src, Train *src, bool check_limit)
01047 {
01048   /* Check whether we may actually construct the trains. */
01049   CommandCost ret = CheckTrainAttachment(src);
01050   if (ret.Failed()) return ret;
01051   ret = CheckTrainAttachment(dst);
01052   if (ret.Failed()) return ret;
01053 
01054   /* Check whether we need to build a new train. */
01055   return check_limit ? CheckNewTrain(original_dst, dst, original_src, src) : CommandCost();
01056 }
01057 
01066 static void ArrangeTrains(Train **dst_head, Train *dst, Train **src_head, Train *src, bool move_chain)
01067 {
01068   /* First determine the front of the two resulting trains */
01069   if (*src_head == *dst_head) {
01070     /* If we aren't moving part(s) to a new train, we are just moving the
01071      * front back and there is not destination head. */
01072     *dst_head = NULL;
01073   } else if (*dst_head == NULL) {
01074     /* If we are moving to a new train the head of the move train would become
01075      * the head of the new vehicle. */
01076     *dst_head = src;
01077   }
01078 
01079   if (src == *src_head) {
01080     /* If we are moving the front of a train then we are, in effect, creating
01081      * a new head for the train. Point to that. Unless we are moving the whole
01082      * train in which case there is not 'source' train anymore.
01083      * In case we are a multiheaded part we want the complete thing to come
01084      * with us, so src->GetNextUnit(), however... when we are e.g. a wagon
01085      * that is followed by a rear multihead we do not want to include that. */
01086     *src_head = move_chain ? NULL :
01087         (src->IsMultiheaded() ? src->GetNextUnit() : src->GetNextVehicle());
01088   }
01089 
01090   /* Now it's just simply removing the part that we are going to move from the
01091    * source train and *if* the destination is a not a new train add the chain
01092    * at the destination location. */
01093   RemoveFromConsist(src, move_chain);
01094   if (*dst_head != src) InsertInConsist(dst, src);
01095 
01096   /* Now normalise the dual heads, that is move the dual heads around in such
01097    * a way that the head and rear of a dual head are in the same train */
01098   NormaliseDualHeads(*src_head);
01099   NormaliseDualHeads(*dst_head);
01100 }
01101 
01107 static void NormaliseTrainHead(Train *head)
01108 {
01109   /* Not much to do! */
01110   if (head == NULL) return;
01111 
01112   /* Tell the 'world' the train changed. */
01113   head->ConsistChanged(false);
01114   UpdateTrainGroupID(head);
01115 
01116   /* Not a front engine, i.e. a free wagon chain. No need to do more. */
01117   if (!head->IsFrontEngine()) return;
01118 
01119   /* Update the refit button and window */
01120   InvalidateWindowData(WC_VEHICLE_REFIT, head->index, VIWD_CONSIST_CHANGED);
01121   SetWindowWidgetDirty(WC_VEHICLE_VIEW, head->index, WID_VV_REFIT);
01122 
01123   /* If we don't have a unit number yet, set one. */
01124   if (head->unitnumber != 0) return;
01125   head->unitnumber = GetFreeUnitNumber(VEH_TRAIN);
01126 }
01127 
01140 CommandCost CmdMoveRailVehicle(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
01141 {
01142   VehicleID s = GB(p1, 0, 20);
01143   VehicleID d = GB(p2, 0, 20);
01144   bool move_chain = HasBit(p1, 20);
01145 
01146   Train *src = Train::GetIfValid(s);
01147   if (src == NULL) return CMD_ERROR;
01148 
01149   CommandCost ret = CheckOwnership(src->owner);
01150   if (ret.Failed()) return ret;
01151 
01152   /* Do not allow moving crashed vehicles inside the depot, it is likely to cause asserts later */
01153   if (src->vehstatus & VS_CRASHED) return CMD_ERROR;
01154 
01155   /* if nothing is selected as destination, try and find a matching vehicle to drag to. */
01156   Train *dst;
01157   if (d == INVALID_VEHICLE) {
01158     dst = src->IsEngine() ? NULL : FindGoodVehiclePos(src);
01159   } else {
01160     dst = Train::GetIfValid(d);
01161     if (dst == NULL) return CMD_ERROR;
01162 
01163     CommandCost ret = CheckOwnership(dst->owner);
01164     if (ret.Failed()) return ret;
01165 
01166     /* Do not allow appending to crashed vehicles, too */
01167     if (dst->vehstatus & VS_CRASHED) return CMD_ERROR;
01168   }
01169 
01170   /* if an articulated part is being handled, deal with its parent vehicle */
01171   src = src->GetFirstEnginePart();
01172   if (dst != NULL) {
01173     dst = dst->GetFirstEnginePart();
01174   }
01175 
01176   /* don't move the same vehicle.. */
01177   if (src == dst) return CommandCost();
01178 
01179   /* locate the head of the two chains */
01180   Train *src_head = src->First();
01181   Train *dst_head;
01182   if (dst != NULL) {
01183     dst_head = dst->First();
01184     if (dst_head->tile != src_head->tile) return CMD_ERROR;
01185     /* Now deal with articulated part of destination wagon */
01186     dst = dst->GetLastEnginePart();
01187   } else {
01188     dst_head = NULL;
01189   }
01190 
01191   if (src->IsRearDualheaded()) return_cmd_error(STR_ERROR_REAR_ENGINE_FOLLOW_FRONT);
01192 
01193   /* When moving all wagons, we can't have the same src_head and dst_head */
01194   if (move_chain && src_head == dst_head) return CommandCost();
01195 
01196   /* When moving a multiheaded part to be place after itself, bail out. */
01197   if (!move_chain && dst != NULL && dst->IsRearDualheaded() && src == dst->other_multiheaded_part) return CommandCost();
01198 
01199   /* Check if all vehicles in the source train are stopped inside a depot. */
01200   if (!src_head->IsStoppedInDepot()) return_cmd_error(STR_ERROR_TRAINS_CAN_ONLY_BE_ALTERED_INSIDE_A_DEPOT);
01201 
01202   /* Check if all vehicles in the destination train are stopped inside a depot. */
01203   if (dst_head != NULL && !dst_head->IsStoppedInDepot()) return_cmd_error(STR_ERROR_TRAINS_CAN_ONLY_BE_ALTERED_INSIDE_A_DEPOT);
01204 
01205   /* First make a backup of the order of the trains. That way we can do
01206    * whatever we want with the order and later on easily revert. */
01207   TrainList original_src;
01208   TrainList original_dst;
01209 
01210   MakeTrainBackup(original_src, src_head);
01211   MakeTrainBackup(original_dst, dst_head);
01212 
01213   /* Also make backup of the original heads as ArrangeTrains can change them.
01214    * For the destination head we do not care if it is the same as the source
01215    * head because in that case it's just a copy. */
01216   Train *original_src_head = src_head;
01217   Train *original_dst_head = (dst_head == src_head ? NULL : dst_head);
01218 
01219   /* We want this information from before the rearrangement, but execute this after the validation. */
01220   bool original_src_head_front_engine = original_src_head != NULL && original_src_head->IsFrontEngine();
01221   bool original_dst_head_front_engine = original_dst_head != NULL && original_dst_head->IsFrontEngine();
01222 
01223   /* (Re)arrange the trains in the wanted arrangement. */
01224   ArrangeTrains(&dst_head, dst, &src_head, src, move_chain);
01225 
01226   if ((flags & DC_AUTOREPLACE) == 0) {
01227     /* If the autoreplace flag is set we do not need to test for the validity
01228      * because we are going to revert the train to its original state. As we
01229      * assume the original state was correct autoreplace can skip this. */
01230     CommandCost ret = ValidateTrains(original_dst_head, dst_head, original_src_head, src_head, true);
01231     if (ret.Failed()) {
01232       /* Restore the train we had. */
01233       RestoreTrainBackup(original_src);
01234       RestoreTrainBackup(original_dst);
01235       return ret;
01236     }
01237   }
01238 
01239   /* do it? */
01240   if (flags & DC_EXEC) {
01241     /* Remove old heads from the statistics */
01242     if (original_src_head_front_engine) GroupStatistics::CountVehicle(original_src_head, -1);
01243     if (original_dst_head_front_engine) GroupStatistics::CountVehicle(original_dst_head, -1);
01244 
01245     /* First normalise the sub types of the chains. */
01246     NormaliseSubtypes(src_head);
01247     NormaliseSubtypes(dst_head);
01248 
01249     /* There are 14 different cases:
01250      *  1) front engine gets moved to a new train, it stays a front engine.
01251      *     a) the 'next' part is a wagon that becomes a free wagon chain.
01252      *     b) the 'next' part is an engine that becomes a front engine.
01253      *     c) there is no 'next' part, nothing else happens
01254      *  2) front engine gets moved to another train, it is not a front engine anymore
01255      *     a) the 'next' part is a wagon that becomes a free wagon chain.
01256      *     b) the 'next' part is an engine that becomes a front engine.
01257      *     c) there is no 'next' part, nothing else happens
01258      *  3) front engine gets moved to later in the current train, it is not a front engine anymore.
01259      *     a) the 'next' part is a wagon that becomes a free wagon chain.
01260      *     b) the 'next' part is an engine that becomes a front engine.
01261      *  4) free wagon gets moved
01262      *     a) the 'next' part is a wagon that becomes a free wagon chain.
01263      *     b) the 'next' part is an engine that becomes a front engine.
01264      *     c) there is no 'next' part, nothing else happens
01265      *  5) non front engine gets moved and becomes a new train, nothing else happens
01266      *  6) non front engine gets moved within a train / to another train, nothing hapens
01267      *  7) wagon gets moved, nothing happens
01268      */
01269     if (src == original_src_head && src->IsEngine() && !src->IsFrontEngine()) {
01270       /* Cases #2 and #3: the front engine gets trashed. */
01271       DeleteWindowById(WC_VEHICLE_VIEW, src->index);
01272       DeleteWindowById(WC_VEHICLE_ORDERS, src->index);
01273       DeleteWindowById(WC_VEHICLE_REFIT, src->index);
01274       DeleteWindowById(WC_VEHICLE_DETAILS, src->index);
01275       DeleteWindowById(WC_VEHICLE_TIMETABLE, src->index);
01276       SetWindowDirty(WC_COMPANY, _current_company);
01277 
01278       /* Delete orders, group stuff and the unit number as we're not the
01279        * front of any vehicle anymore. */
01280       DeleteVehicleOrders(src);
01281       RemoveVehicleFromGroup(src);
01282       src->unitnumber = 0;
01283     }
01284 
01285     /* We weren't a front engine but are becoming one. So
01286      * we should be put in the default group. */
01287     if (original_src_head != src && dst_head == src) {
01288       SetTrainGroupID(src, DEFAULT_GROUP);
01289       SetWindowDirty(WC_COMPANY, _current_company);
01290     }
01291 
01292     /* Add new heads to statistics */
01293     if (src_head != NULL && src_head->IsFrontEngine()) GroupStatistics::CountVehicle(src_head, 1);
01294     if (dst_head != NULL && dst_head->IsFrontEngine()) GroupStatistics::CountVehicle(dst_head, 1);
01295 
01296     /* Handle 'new engine' part of cases #1b, #2b, #3b, #4b and #5 in NormaliseTrainHead. */
01297     NormaliseTrainHead(src_head);
01298     NormaliseTrainHead(dst_head);
01299 
01300     if ((flags & DC_NO_CARGO_CAP_CHECK) == 0) {
01301       CheckCargoCapacity(src_head);
01302       CheckCargoCapacity(dst_head);
01303     }
01304 
01305     /* We are undoubtedly changing something in the depot and train list. */
01306     InvalidateWindowData(WC_VEHICLE_DEPOT, src->tile);
01307     InvalidateWindowClassesData(WC_TRAINS_LIST, 0);
01308   } else {
01309     /* We don't want to execute what we're just tried. */
01310     RestoreTrainBackup(original_src);
01311     RestoreTrainBackup(original_dst);
01312   }
01313 
01314   return CommandCost();
01315 }
01316 
01328 CommandCost CmdSellRailWagon(DoCommandFlag flags, Vehicle *t, uint16 data, uint32 user)
01329 {
01330   /* Check if we deleted a vehicle window */
01331   Window *w = NULL;
01332 
01333   /* Sell a chain of vehicles or not? */
01334   bool sell_chain = HasBit(data, 0);
01335 
01336   Train *v = Train::From(t)->GetFirstEnginePart();
01337   Train *first = v->First();
01338 
01339   if (v->IsRearDualheaded()) return_cmd_error(STR_ERROR_REAR_ENGINE_FOLLOW_FRONT);
01340 
01341   /* First make a backup of the order of the train. That way we can do
01342    * whatever we want with the order and later on easily revert. */
01343   TrainList original;
01344   MakeTrainBackup(original, first);
01345 
01346   /* We need to keep track of the new head and the head of what we're going to sell. */
01347   Train *new_head = first;
01348   Train *sell_head = NULL;
01349 
01350   /* Split the train in the wanted way. */
01351   ArrangeTrains(&sell_head, NULL, &new_head, v, sell_chain);
01352 
01353   /* We don't need to validate the second train; it's going to be sold. */
01354   CommandCost ret = ValidateTrains(NULL, NULL, first, new_head, (flags & DC_AUTOREPLACE) == 0);
01355   if (ret.Failed()) {
01356     /* Restore the train we had. */
01357     RestoreTrainBackup(original);
01358     return ret;
01359   }
01360 
01361   CommandCost cost(EXPENSES_NEW_VEHICLES);
01362   for (Train *t = sell_head; t != NULL; t = t->Next()) cost.AddCost(-t->value);
01363 
01364   if (first->orders.list == NULL && !OrderList::CanAllocateItem()) {
01365     return_cmd_error(STR_ERROR_NO_MORE_SPACE_FOR_ORDERS);
01366   }
01367 
01368   /* do it? */
01369   if (flags & DC_EXEC) {
01370     /* First normalise the sub types of the chain. */
01371     NormaliseSubtypes(new_head);
01372 
01373     if (v == first && v->IsEngine() && !sell_chain && new_head != NULL && new_head->IsFrontEngine()) {
01374       /* We are selling the front engine. In this case we want to
01375        * 'give' the order, unit number and such to the new head. */
01376       new_head->orders.list = first->orders.list;
01377       new_head->AddToShared(first);
01378       DeleteVehicleOrders(first);
01379 
01380       /* Copy other important data from the front engine */
01381       new_head->CopyVehicleConfigAndStatistics(first);
01382       GroupStatistics::CountVehicle(new_head, 1); // after copying over the profit
01383 
01384       /* If we deleted a window then open a new one for the 'new' train */
01385       if (IsLocalCompany() && w != NULL) ShowVehicleViewWindow(new_head);
01386     } else if (v->IsPrimaryVehicle() && data & (MAKE_ORDER_BACKUP_FLAG >> 20)) {
01387       OrderBackup::Backup(v, user);
01388     }
01389 
01390     /* We need to update the information about the train. */
01391     NormaliseTrainHead(new_head);
01392 
01393     /* We are undoubtedly changing something in the depot and train list. */
01394     InvalidateWindowData(WC_VEHICLE_DEPOT, v->tile);
01395     InvalidateWindowClassesData(WC_TRAINS_LIST, 0);
01396 
01397     /* Actually delete the sold 'goods' */
01398     delete sell_head;
01399   } else {
01400     /* We don't want to execute what we're just tried. */
01401     RestoreTrainBackup(original);
01402   }
01403 
01404   return cost;
01405 }
01406 
01407 void Train::UpdateDeltaXY(Direction direction)
01408 {
01409   /* Set common defaults. */
01410   this->x_offs    = -1;
01411   this->y_offs    = -1;
01412   this->x_extent  =  3;
01413   this->y_extent  =  3;
01414   this->z_extent  =  6;
01415   this->x_bb_offs =  0;
01416   this->y_bb_offs =  0;
01417 
01418   if (!IsDiagonalDirection(direction)) {
01419     static const int _sign_table[] =
01420     {
01421       // x, y
01422       -1, -1, // DIR_N
01423       -1,  1, // DIR_E
01424        1,  1, // DIR_S
01425        1, -1, // DIR_W
01426     };
01427 
01428     int half_shorten = (VEHICLE_LENGTH - this->gcache.cached_veh_length) / 2;
01429 
01430     /* For all straight directions, move the bound box to the centre of the vehicle, but keep the size. */
01431     this->x_offs -= half_shorten * _sign_table[direction];
01432     this->y_offs -= half_shorten * _sign_table[direction + 1];
01433     this->x_extent += this->x_bb_offs = half_shorten * _sign_table[direction];
01434     this->y_extent += this->y_bb_offs = half_shorten * _sign_table[direction + 1];
01435   } else {
01436     switch (direction) {
01437         /* Shorten southern corner of the bounding box according the vehicle length
01438          * and center the bounding box on the vehicle. */
01439       case DIR_NE:
01440         this->x_offs    = 1 - (this->gcache.cached_veh_length + 1) / 2;
01441         this->x_extent  = this->gcache.cached_veh_length - 1;
01442         this->x_bb_offs = -1;
01443         break;
01444 
01445       case DIR_NW:
01446         this->y_offs    = 1 - (this->gcache.cached_veh_length + 1) / 2;
01447         this->y_extent  = this->gcache.cached_veh_length - 1;
01448         this->y_bb_offs = -1;
01449         break;
01450 
01451         /* Move northern corner of the bounding box down according to vehicle length
01452          * and center the bounding box on the vehicle. */
01453       case DIR_SW:
01454         this->x_offs    = 1 + (this->gcache.cached_veh_length + 1) / 2 - VEHICLE_LENGTH;
01455         this->x_extent  = VEHICLE_LENGTH - 1;
01456         this->x_bb_offs = VEHICLE_LENGTH - this->gcache.cached_veh_length - 1;
01457         break;
01458 
01459       case DIR_SE:
01460         this->y_offs    = 1 + (this->gcache.cached_veh_length + 1) / 2 - VEHICLE_LENGTH;
01461         this->y_extent  = VEHICLE_LENGTH - 1;
01462         this->y_bb_offs = VEHICLE_LENGTH - this->gcache.cached_veh_length - 1;
01463         break;
01464 
01465       default:
01466         NOT_REACHED();
01467     }
01468   }
01469 }
01470 
01475 static void MarkTrainAsStuck(Train *v)
01476 {
01477   if (!HasBit(v->flags, VRF_TRAIN_STUCK)) {
01478     /* It is the first time the problem occurred, set the "train stuck" flag. */
01479     SetBit(v->flags, VRF_TRAIN_STUCK);
01480 
01481     v->wait_counter = 0;
01482 
01483     /* Stop train */
01484     v->cur_speed = 0;
01485     v->subspeed = 0;
01486     v->SetLastSpeed();
01487 
01488     SetWindowWidgetDirty(WC_VEHICLE_VIEW, v->index, WID_VV_START_STOP);
01489   }
01490 }
01491 
01499 static void SwapTrainFlags(uint16 *swap_flag1, uint16 *swap_flag2)
01500 {
01501   uint16 flag1 = *swap_flag1;
01502   uint16 flag2 = *swap_flag2;
01503 
01504   /* Clear the flags */
01505   ClrBit(*swap_flag1, GVF_GOINGUP_BIT);
01506   ClrBit(*swap_flag1, GVF_GOINGDOWN_BIT);
01507   ClrBit(*swap_flag2, GVF_GOINGUP_BIT);
01508   ClrBit(*swap_flag2, GVF_GOINGDOWN_BIT);
01509 
01510   /* Reverse the rail-flags (if needed) */
01511   if (HasBit(flag1, GVF_GOINGUP_BIT)) {
01512     SetBit(*swap_flag2, GVF_GOINGDOWN_BIT);
01513   } else if (HasBit(flag1, GVF_GOINGDOWN_BIT)) {
01514     SetBit(*swap_flag2, GVF_GOINGUP_BIT);
01515   }
01516   if (HasBit(flag2, GVF_GOINGUP_BIT)) {
01517     SetBit(*swap_flag1, GVF_GOINGDOWN_BIT);
01518   } else if (HasBit(flag2, GVF_GOINGDOWN_BIT)) {
01519     SetBit(*swap_flag1, GVF_GOINGUP_BIT);
01520   }
01521 }
01522 
01527 static void UpdateStatusAfterSwap(Train *v)
01528 {
01529   /* Reverse the direction. */
01530   if (v->track != TRACK_BIT_DEPOT) v->direction = ReverseDir(v->direction);
01531 
01532   /* Call the proper EnterTile function unless we are in a wormhole. */
01533   if (v->track != TRACK_BIT_WORMHOLE) {
01534     VehicleEnterTile(v, v->tile, v->x_pos, v->y_pos);
01535   } else {
01536     /* VehicleEnter_TunnelBridge() sets TRACK_BIT_WORMHOLE when the vehicle
01537      * is on the last bit of the bridge head (frame == TILE_SIZE - 1).
01538      * If we were swapped with such a vehicle, we have set TRACK_BIT_WORMHOLE,
01539      * when we shouldn't have. Check if this is the case. */
01540     TileIndex vt = TileVirtXY(v->x_pos, v->y_pos);
01541     if (IsTileType(vt, MP_TUNNELBRIDGE)) {
01542       VehicleEnterTile(v, vt, v->x_pos, v->y_pos);
01543       if (v->track != TRACK_BIT_WORMHOLE && IsBridgeTile(v->tile)) {
01544         /* We have just left the wormhole, possibly set the
01545          * "goingdown" bit. UpdateInclination() can be used
01546          * because we are at the border of the tile. */
01547         VehicleUpdatePosition(v);
01548         v->UpdateInclination(true, true);
01549         return;
01550       }
01551     }
01552   }
01553 
01554   VehicleUpdatePosition(v);
01555   v->UpdateViewport(true, true);
01556 }
01557 
01564 void ReverseTrainSwapVeh(Train *v, int l, int r)
01565 {
01566   Train *a, *b;
01567 
01568   /* locate vehicles to swap */
01569   for (a = v; l != 0; l--) a = a->Next();
01570   for (b = v; r != 0; r--) b = b->Next();
01571 
01572   if (a != b) {
01573     /* swap the hidden bits */
01574     {
01575       uint16 tmp = (a->vehstatus & ~VS_HIDDEN) | (b->vehstatus & VS_HIDDEN);
01576       b->vehstatus = (b->vehstatus & ~VS_HIDDEN) | (a->vehstatus & VS_HIDDEN);
01577       a->vehstatus = tmp;
01578     }
01579 
01580     Swap(a->track, b->track);
01581     Swap(a->direction, b->direction);
01582     Swap(a->x_pos, b->x_pos);
01583     Swap(a->y_pos, b->y_pos);
01584     Swap(a->tile,  b->tile);
01585     Swap(a->z_pos, b->z_pos);
01586 
01587     SwapTrainFlags(&a->gv_flags, &b->gv_flags);
01588 
01589     UpdateStatusAfterSwap(a);
01590     UpdateStatusAfterSwap(b);
01591   } else {
01592     /* Swap GVF_GOINGUP_BIT/GVF_GOINGDOWN_BIT.
01593      * This is a little bit redundant way, a->gv_flags will
01594      * be (re)set twice, but it reduces code duplication */
01595     SwapTrainFlags(&a->gv_flags, &a->gv_flags);
01596     UpdateStatusAfterSwap(a);
01597   }
01598 }
01599 
01600 
01606 static Vehicle *TrainOnTileEnum(Vehicle *v, void *)
01607 {
01608   return (v->type == VEH_TRAIN) ? v : NULL;
01609 }
01610 
01611 
01618 static Vehicle *TrainApproachingCrossingEnum(Vehicle *v, void *data)
01619 {
01620   if (v->type != VEH_TRAIN || (v->vehstatus & VS_CRASHED)) return NULL;
01621 
01622   Train *t = Train::From(v);
01623   if (!t->IsFrontEngine()) return NULL;
01624 
01625   TileIndex tile = *(TileIndex *)data;
01626 
01627   if (TrainApproachingCrossingTile(t) != tile) return NULL;
01628 
01629   return t;
01630 }
01631 
01632 
01639 static bool TrainApproachingCrossing(TileIndex tile)
01640 {
01641   assert(IsLevelCrossingTile(tile));
01642 
01643   DiagDirection dir = AxisToDiagDir(GetCrossingRailAxis(tile));
01644   TileIndex tile_from = tile + TileOffsByDiagDir(dir);
01645 
01646   if (HasVehicleOnPos(tile_from, &tile, &TrainApproachingCrossingEnum)) return true;
01647 
01648   dir = ReverseDiagDir(dir);
01649   tile_from = tile + TileOffsByDiagDir(dir);
01650 
01651   return HasVehicleOnPos(tile_from, &tile, &TrainApproachingCrossingEnum);
01652 }
01653 
01654 
01661 void UpdateLevelCrossing(TileIndex tile, bool sound)
01662 {
01663   assert(IsLevelCrossingTile(tile));
01664 
01665   /* train on crossing || train approaching crossing || reserved */
01666   bool new_state = HasVehicleOnPos(tile, NULL, &TrainOnTileEnum) || TrainApproachingCrossing(tile) || HasCrossingReservation(tile);
01667 
01668   if (new_state != IsCrossingBarred(tile)) {
01669     if (new_state && sound) {
01670       if (_settings_client.sound.ambient) SndPlayTileFx(SND_0E_LEVEL_CROSSING, tile);
01671     }
01672     SetCrossingBarred(tile, new_state);
01673     MarkTileDirtyByTile(tile);
01674   }
01675 }
01676 
01677 
01683 static inline void MaybeBarCrossingWithSound(TileIndex tile)
01684 {
01685   if (!IsCrossingBarred(tile)) {
01686     BarCrossing(tile);
01687     if (_settings_client.sound.ambient) SndPlayTileFx(SND_0E_LEVEL_CROSSING, tile);
01688     MarkTileDirtyByTile(tile);
01689   }
01690 }
01691 
01692 
01698 static void AdvanceWagonsBeforeSwap(Train *v)
01699 {
01700   Train *base = v;
01701   Train *first = base; // first vehicle to move
01702   Train *last = v->Last(); // last vehicle to move
01703   uint length = CountVehiclesInChain(v);
01704 
01705   while (length > 2) {
01706     last = last->Previous();
01707     first = first->Next();
01708 
01709     int differential = base->CalcNextVehicleOffset() - last->CalcNextVehicleOffset();
01710 
01711     /* do not update images now
01712      * negative differential will be handled in AdvanceWagonsAfterSwap() */
01713     for (int i = 0; i < differential; i++) TrainController(first, last->Next());
01714 
01715     base = first; // == base->Next()
01716     length -= 2;
01717   }
01718 }
01719 
01720 
01726 static void AdvanceWagonsAfterSwap(Train *v)
01727 {
01728   /* first of all, fix the situation when the train was entering a depot */
01729   Train *dep = v; // last vehicle in front of just left depot
01730   while (dep->Next() != NULL && (dep->track == TRACK_BIT_DEPOT || dep->Next()->track != TRACK_BIT_DEPOT)) {
01731     dep = dep->Next(); // find first vehicle outside of a depot, with next vehicle inside a depot
01732   }
01733 
01734   Train *leave = dep->Next(); // first vehicle in a depot we are leaving now
01735 
01736   if (leave != NULL) {
01737     /* 'pull' next wagon out of the depot, so we won't miss it (it could stay in depot forever) */
01738     int d = TicksToLeaveDepot(dep);
01739 
01740     if (d <= 0) {
01741       leave->vehstatus &= ~VS_HIDDEN; // move it out of the depot
01742       leave->track = TrackToTrackBits(GetRailDepotTrack(leave->tile));
01743       for (int i = 0; i >= d; i--) TrainController(leave, NULL); // maybe move it, and maybe let another wagon leave
01744     }
01745   } else {
01746     dep = NULL; // no vehicle in a depot, so no vehicle leaving a depot
01747   }
01748 
01749   Train *base = v;
01750   Train *first = base; // first vehicle to move
01751   Train *last = v->Last(); // last vehicle to move
01752   uint length = CountVehiclesInChain(v);
01753 
01754   /* We have to make sure all wagons that leave a depot because of train reversing are moved correctly
01755    * they have already correct spacing, so we have to make sure they are moved how they should */
01756   bool nomove = (dep == NULL); // If there is no vehicle leaving a depot, limit the number of wagons moved immediately.
01757 
01758   while (length > 2) {
01759     /* we reached vehicle (originally) in front of a depot, stop now
01760      * (we would move wagons that are already moved with new wagon length). */
01761     if (base == dep) break;
01762 
01763     /* the last wagon was that one leaving a depot, so do not move it anymore */
01764     if (last == dep) nomove = true;
01765 
01766     last = last->Previous();
01767     first = first->Next();
01768 
01769     int differential = last->CalcNextVehicleOffset() - base->CalcNextVehicleOffset();
01770 
01771     /* do not update images now */
01772     for (int i = 0; i < differential; i++) TrainController(first, (nomove ? last->Next() : NULL));
01773 
01774     base = first; // == base->Next()
01775     length -= 2;
01776   }
01777 }
01778 
01783 void ReverseTrainDirection(Train *v)
01784 {
01785   if (IsRailDepotTile(v->tile)) {
01786     InvalidateWindowData(WC_VEHICLE_DEPOT, v->tile);
01787   }
01788 
01789   /* Clear path reservation in front if train is not stuck. */
01790   if (!HasBit(v->flags, VRF_TRAIN_STUCK)) FreeTrainTrackReservation(v);
01791 
01792   /* Check if we were approaching a rail/road-crossing */
01793   TileIndex crossing = TrainApproachingCrossingTile(v);
01794 
01795   /* count number of vehicles */
01796   int r = CountVehiclesInChain(v) - 1;  // number of vehicles - 1
01797 
01798   AdvanceWagonsBeforeSwap(v);
01799 
01800   /* swap start<>end, start+1<>end-1, ... */
01801   int l = 0;
01802   do {
01803     ReverseTrainSwapVeh(v, l++, r--);
01804   } while (l <= r);
01805 
01806   AdvanceWagonsAfterSwap(v);
01807 
01808   if (IsRailDepotTile(v->tile)) {
01809     InvalidateWindowData(WC_VEHICLE_DEPOT, v->tile);
01810   }
01811 
01812   ToggleBit(v->flags, VRF_TOGGLE_REVERSE);
01813 
01814   ClrBit(v->flags, VRF_REVERSING);
01815 
01816   /* recalculate cached data */
01817   v->ConsistChanged(true);
01818 
01819   /* update all images */
01820   for (Train *u = v; u != NULL; u = u->Next()) u->UpdateViewport(false, false);
01821 
01822   /* update crossing we were approaching */
01823   if (crossing != INVALID_TILE) UpdateLevelCrossing(crossing);
01824 
01825   /* maybe we are approaching crossing now, after reversal */
01826   crossing = TrainApproachingCrossingTile(v);
01827   if (crossing != INVALID_TILE) MaybeBarCrossingWithSound(crossing);
01828 
01829   /* If we are inside a depot after reversing, don't bother with path reserving. */
01830   if (v->track == TRACK_BIT_DEPOT) {
01831     /* Can't be stuck here as inside a depot is always a safe tile. */
01832     if (HasBit(v->flags, VRF_TRAIN_STUCK)) SetWindowWidgetDirty(WC_VEHICLE_VIEW, v->index, WID_VV_START_STOP);
01833     ClrBit(v->flags, VRF_TRAIN_STUCK);
01834     return;
01835   }
01836 
01837   /* TrainExitDir does not always produce the desired dir for depots and
01838    * tunnels/bridges that is needed for UpdateSignalsOnSegment. */
01839   DiagDirection dir = TrainExitDir(v->direction, v->track);
01840   if (IsRailDepotTile(v->tile) || IsTileType(v->tile, MP_TUNNELBRIDGE)) dir = INVALID_DIAGDIR;
01841 
01842   if (UpdateSignalsOnSegment(v->tile, dir, v->owner) == SIGSEG_PBS || _settings_game.pf.reserve_paths) {
01843     /* If we are currently on a tile with conventional signals, we can't treat the
01844      * current tile as a safe tile or we would enter a PBS block without a reservation. */
01845     bool first_tile_okay = !(IsTileType(v->tile, MP_RAILWAY) &&
01846       HasSignalOnTrackdir(v->tile, v->GetVehicleTrackdir()) &&
01847       !IsPbsSignal(GetSignalType(v->tile, FindFirstTrack(v->track))));
01848 
01849     /* If we are on a depot tile facing outwards, do not treat the current tile as safe. */
01850     if (IsRailDepotTile(v->tile) && TrackdirToExitdir(v->GetVehicleTrackdir()) == GetRailDepotDirection(v->tile)) first_tile_okay = false;
01851 
01852     if (IsRailStationTile(v->tile)) SetRailStationPlatformReservation(v->tile, TrackdirToExitdir(v->GetVehicleTrackdir()), true);
01853     if (TryPathReserve(v, false, first_tile_okay)) {
01854       /* Do a look-ahead now in case our current tile was already a safe tile. */
01855       CheckNextTrainTile(v);
01856     } else if (v->current_order.GetType() != OT_LOADING) {
01857       /* Do not wait for a way out when we're still loading */
01858       MarkTrainAsStuck(v);
01859     }
01860   } else if (HasBit(v->flags, VRF_TRAIN_STUCK)) {
01861     /* A train not inside a PBS block can't be stuck. */
01862     ClrBit(v->flags, VRF_TRAIN_STUCK);
01863     v->wait_counter = 0;
01864   }
01865 }
01866 
01876 CommandCost CmdReverseTrainDirection(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
01877 {
01878   Train *v = Train::GetIfValid(p1);
01879   if (v == NULL) return CMD_ERROR;
01880 
01881   CommandCost ret = CheckOwnership(v->owner);
01882   if (ret.Failed()) return ret;
01883 
01884   if (p2 != 0) {
01885     /* turn a single unit around */
01886 
01887     if (v->IsMultiheaded() || HasBit(EngInfo(v->engine_type)->callback_mask, CBM_VEHICLE_ARTIC_ENGINE)) {
01888       return_cmd_error(STR_ERROR_CAN_T_REVERSE_DIRECTION_RAIL_VEHICLE_MULTIPLE_UNITS);
01889     }
01890     if (!HasBit(EngInfo(v->engine_type)->misc_flags, EF_RAIL_FLIPS)) return CMD_ERROR;
01891 
01892     Train *front = v->First();
01893     /* make sure the vehicle is stopped in the depot */
01894     if (!front->IsStoppedInDepot()) {
01895       return_cmd_error(STR_ERROR_TRAINS_CAN_ONLY_BE_ALTERED_INSIDE_A_DEPOT);
01896     }
01897 
01898     if (flags & DC_EXEC) {
01899       ToggleBit(v->flags, VRF_REVERSE_DIRECTION);
01900 
01901       front->ConsistChanged(false);
01902       SetWindowDirty(WC_VEHICLE_DEPOT, front->tile);
01903       SetWindowDirty(WC_VEHICLE_DETAILS, front->index);
01904       SetWindowDirty(WC_VEHICLE_VIEW, front->index);
01905       SetWindowClassesDirty(WC_TRAINS_LIST);
01906     }
01907   } else {
01908     /* turn the whole train around */
01909     if ((v->vehstatus & VS_CRASHED) || v->breakdown_ctr != 0) return CMD_ERROR;
01910 
01911     if (flags & DC_EXEC) {
01912       /* Properly leave the station if we are loading and won't be loading anymore */
01913       if (v->current_order.IsType(OT_LOADING)) {
01914         const Vehicle *last = v;
01915         while (last->Next() != NULL) last = last->Next();
01916 
01917         /* not a station || different station --> leave the station */
01918         if (!IsTileType(last->tile, MP_STATION) || GetStationIndex(last->tile) != GetStationIndex(v->tile)) {
01919           v->LeaveStation();
01920         }
01921       }
01922 
01923       /* We cancel any 'skip signal at dangers' here */
01924       v->force_proceed = TFP_NONE;
01925       SetWindowDirty(WC_VEHICLE_VIEW, v->index);
01926 
01927       if (_settings_game.vehicle.train_acceleration_model != AM_ORIGINAL && v->cur_speed != 0) {
01928         ToggleBit(v->flags, VRF_REVERSING);
01929       } else {
01930         v->cur_speed = 0;
01931         v->SetLastSpeed();
01932         HideFillingPercent(&v->fill_percent_te_id);
01933         ReverseTrainDirection(v);
01934       }
01935     }
01936   }
01937   return CommandCost();
01938 }
01939 
01949 CommandCost CmdForceTrainProceed(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
01950 {
01951   Train *t = Train::GetIfValid(p1);
01952   if (t == NULL) return CMD_ERROR;
01953 
01954   if (!t->IsPrimaryVehicle()) return CMD_ERROR;
01955 
01956   CommandCost ret = CheckOwnership(t->owner);
01957   if (ret.Failed()) return ret;
01958 
01959 
01960   if (flags & DC_EXEC) {
01961     /* If we are forced to proceed, cancel that order.
01962      * If we are marked stuck we would want to force the train
01963      * to proceed to the next signal. In the other cases we
01964      * would like to pass the signal at danger and run till the
01965      * next signal we encounter. */
01966     t->force_proceed = t->force_proceed == TFP_SIGNAL ? TFP_NONE : HasBit(t->flags, VRF_TRAIN_STUCK) || t->IsChainInDepot() ? TFP_STUCK : TFP_SIGNAL;
01967     SetWindowDirty(WC_VEHICLE_VIEW, t->index);
01968   }
01969 
01970   return CommandCost();
01971 }
01972 
01980 static FindDepotData FindClosestTrainDepot(Train *v, int max_distance)
01981 {
01982   assert(!(v->vehstatus & VS_CRASHED));
01983 
01984   if (IsRailDepotTile(v->tile)) return FindDepotData(v->tile, 0);
01985 
01986   PBSTileInfo origin = FollowTrainReservation(v);
01987   if (IsRailDepotTile(origin.tile)) return FindDepotData(origin.tile, 0);
01988 
01989   switch (_settings_game.pf.pathfinder_for_trains) {
01990     case VPF_NPF: return NPFTrainFindNearestDepot(v, max_distance);
01991     case VPF_YAPF: return YapfTrainFindNearestDepot(v, max_distance);
01992 
01993     default: NOT_REACHED();
01994   }
01995 }
01996 
02004 bool Train::FindClosestDepot(TileIndex *location, DestinationID *destination, bool *reverse)
02005 {
02006   FindDepotData tfdd = FindClosestTrainDepot(this, 0);
02007   if (tfdd.best_length == UINT_MAX) return false;
02008 
02009   if (location    != NULL) *location    = tfdd.tile;
02010   if (destination != NULL) *destination = GetDepotIndex(tfdd.tile);
02011   if (reverse     != NULL) *reverse     = tfdd.reverse;
02012 
02013   return true;
02014 }
02015 
02017 void Train::PlayLeaveStationSound() const
02018 {
02019   static const SoundFx sfx[] = {
02020     SND_04_TRAIN,
02021     SND_0A_TRAIN_HORN,
02022     SND_0A_TRAIN_HORN,
02023     SND_47_MAGLEV_2,
02024     SND_41_MAGLEV
02025   };
02026 
02027   if (PlayVehicleSound(this, VSE_START)) return;
02028 
02029   EngineID engtype = this->engine_type;
02030   SndPlayVehicleFx(sfx[RailVehInfo(engtype)->engclass], this);
02031 }
02032 
02037 static void CheckNextTrainTile(Train *v)
02038 {
02039   /* Don't do any look-ahead if path_backoff_interval is 255. */
02040   if (_settings_game.pf.path_backoff_interval == 255) return;
02041 
02042   /* Exit if we are inside a depot. */
02043   if (v->track == TRACK_BIT_DEPOT) return;
02044 
02045   switch (v->current_order.GetType()) {
02046     /* Exit if we reached our destination depot. */
02047     case OT_GOTO_DEPOT:
02048       if (v->tile == v->dest_tile) return;
02049       break;
02050 
02051     case OT_GOTO_WAYPOINT:
02052       /* If we reached our waypoint, make sure we see that. */
02053       if (IsRailWaypointTile(v->tile) && GetStationIndex(v->tile) == v->current_order.GetDestination()) ProcessOrders(v);
02054       break;
02055 
02056     case OT_NOTHING:
02057     case OT_LEAVESTATION:
02058     case OT_LOADING:
02059       /* Exit if the current order doesn't have a destination, but the train has orders. */
02060       if (v->GetNumOrders() > 0) return;
02061       break;
02062 
02063     default:
02064       break;
02065   }
02066   /* Exit if we are on a station tile and are going to stop. */
02067   if (IsRailStationTile(v->tile) && v->current_order.ShouldStopAtStation(v, GetStationIndex(v->tile))) return;
02068 
02069   Trackdir td = v->GetVehicleTrackdir();
02070 
02071   /* On a tile with a red non-pbs signal, don't look ahead. */
02072   if (IsTileType(v->tile, MP_RAILWAY) && HasSignalOnTrackdir(v->tile, td) &&
02073       !IsPbsSignal(GetSignalType(v->tile, TrackdirToTrack(td))) &&
02074       GetSignalStateByTrackdir(v->tile, td) == SIGNAL_STATE_RED) return;
02075 
02076   CFollowTrackRail ft(v);
02077   if (!ft.Follow(v->tile, td)) return;
02078 
02079   if (!HasReservedTracks(ft.m_new_tile, TrackdirBitsToTrackBits(ft.m_new_td_bits))) {
02080     /* Next tile is not reserved. */
02081     if (KillFirstBit(ft.m_new_td_bits) == TRACKDIR_BIT_NONE) {
02082       if (HasPbsSignalOnTrackdir(ft.m_new_tile, FindFirstTrackdir(ft.m_new_td_bits))) {
02083         /* If the next tile is a PBS signal, try to make a reservation. */
02084         TrackBits tracks = TrackdirBitsToTrackBits(ft.m_new_td_bits);
02085         if (_settings_game.pf.forbid_90_deg) {
02086           tracks &= ~TrackCrossesTracks(TrackdirToTrack(ft.m_old_td));
02087         }
02088         ChooseTrainTrack(v, ft.m_new_tile, ft.m_exitdir, tracks, false, NULL, false);
02089       }
02090     }
02091   }
02092 }
02093 
02099 static bool CheckTrainStayInDepot(Train *v)
02100 {
02101   /* bail out if not all wagons are in the same depot or not in a depot at all */
02102   for (const Train *u = v; u != NULL; u = u->Next()) {
02103     if (u->track != TRACK_BIT_DEPOT || u->tile != v->tile) return false;
02104   }
02105 
02106   /* if the train got no power, then keep it in the depot */
02107   if (v->gcache.cached_power == 0) {
02108     v->vehstatus |= VS_STOPPED;
02109     SetWindowDirty(WC_VEHICLE_DEPOT, v->tile);
02110     return true;
02111   }
02112 
02113   SigSegState seg_state;
02114 
02115   if (v->force_proceed == TFP_NONE) {
02116     /* force proceed was not pressed */
02117     if (++v->wait_counter < 37) {
02118       SetWindowClassesDirty(WC_TRAINS_LIST);
02119       return true;
02120     }
02121 
02122     v->wait_counter = 0;
02123 
02124     seg_state = _settings_game.pf.reserve_paths ? SIGSEG_PBS : UpdateSignalsOnSegment(v->tile, INVALID_DIAGDIR, v->owner);
02125     if (seg_state == SIGSEG_FULL || HasDepotReservation(v->tile)) {
02126       /* Full and no PBS signal in block or depot reserved, can't exit. */
02127       SetWindowClassesDirty(WC_TRAINS_LIST);
02128       return true;
02129     }
02130   } else {
02131     seg_state = _settings_game.pf.reserve_paths ? SIGSEG_PBS : UpdateSignalsOnSegment(v->tile, INVALID_DIAGDIR, v->owner);
02132   }
02133 
02134   /* We are leaving a depot, but have to go to the exact same one; re-enter */
02135   if (v->current_order.IsType(OT_GOTO_DEPOT) && v->tile == v->dest_tile) {
02136     /* We need to have a reservation for this to work. */
02137     if (HasDepotReservation(v->tile)) return true;
02138     SetDepotReservation(v->tile, true);
02139     VehicleEnterDepot(v);
02140     return true;
02141   }
02142 
02143   /* Only leave when we can reserve a path to our destination. */
02144   if (seg_state == SIGSEG_PBS && !TryPathReserve(v) && v->force_proceed == TFP_NONE) {
02145     /* No path and no force proceed. */
02146     SetWindowClassesDirty(WC_TRAINS_LIST);
02147     MarkTrainAsStuck(v);
02148     return true;
02149   }
02150 
02151   SetDepotReservation(v->tile, true);
02152   if (_settings_client.gui.show_track_reservation) MarkTileDirtyByTile(v->tile);
02153 
02154   VehicleServiceInDepot(v);
02155   SetWindowClassesDirty(WC_TRAINS_LIST);
02156   v->PlayLeaveStationSound();
02157 
02158   v->track = TRACK_BIT_X;
02159   if (v->direction & 2) v->track = TRACK_BIT_Y;
02160 
02161   v->vehstatus &= ~VS_HIDDEN;
02162   v->cur_speed = 0;
02163 
02164   v->UpdateViewport(true, true);
02165   VehicleUpdatePosition(v);
02166   UpdateSignalsOnSegment(v->tile, INVALID_DIAGDIR, v->owner);
02167   v->UpdateAcceleration();
02168   InvalidateWindowData(WC_VEHICLE_DEPOT, v->tile);
02169 
02170   return false;
02171 }
02172 
02179 static void ClearPathReservation(const Train *v, TileIndex tile, Trackdir track_dir)
02180 {
02181   DiagDirection dir = TrackdirToExitdir(track_dir);
02182 
02183   if (IsTileType(tile, MP_TUNNELBRIDGE)) {
02184     /* Are we just leaving a tunnel/bridge? */
02185     if (GetTunnelBridgeDirection(tile) == ReverseDiagDir(dir)) {
02186       TileIndex end = GetOtherTunnelBridgeEnd(tile);
02187 
02188       if (TunnelBridgeIsFree(tile, end, v).Succeeded()) {
02189         /* Free the reservation only if no other train is on the tiles. */
02190         SetTunnelBridgeReservation(tile, false);
02191         SetTunnelBridgeReservation(end, false);
02192 
02193         if (_settings_client.gui.show_track_reservation) {
02194           MarkTileDirtyByTile(tile);
02195           MarkTileDirtyByTile(end);
02196         }
02197       }
02198     }
02199   } else if (IsRailStationTile(tile)) {
02200     TileIndex new_tile = TileAddByDiagDir(tile, dir);
02201     /* If the new tile is not a further tile of the same station, we
02202      * clear the reservation for the whole platform. */
02203     if (!IsCompatibleTrainStationTile(new_tile, tile)) {
02204       SetRailStationPlatformReservation(tile, ReverseDiagDir(dir), false);
02205     }
02206   } else {
02207     /* Any other tile */
02208     UnreserveRailTrack(tile, TrackdirToTrack(track_dir));
02209   }
02210 }
02211 
02218 void FreeTrainTrackReservation(const Train *v, TileIndex origin, Trackdir orig_td)
02219 {
02220   assert(v->IsFrontEngine());
02221 
02222   TileIndex tile = origin != INVALID_TILE ? origin : v->tile;
02223   Trackdir  td = orig_td != INVALID_TRACKDIR ? orig_td : v->GetVehicleTrackdir();
02224   bool      free_tile = tile != v->tile || !(IsRailStationTile(v->tile) || IsTileType(v->tile, MP_TUNNELBRIDGE));
02225   StationID station_id = IsRailStationTile(v->tile) ? GetStationIndex(v->tile) : INVALID_STATION;
02226 
02227   /* Can't be holding a reservation if we enter a depot. */
02228   if (IsRailDepotTile(tile) && TrackdirToExitdir(td) != GetRailDepotDirection(tile)) return;
02229   if (v->track == TRACK_BIT_DEPOT) {
02230     /* Front engine is in a depot. We enter if some part is not in the depot. */
02231     for (const Train *u = v; u != NULL; u = u->Next()) {
02232       if (u->track != TRACK_BIT_DEPOT || u->tile != v->tile) return;
02233     }
02234   }
02235   /* Don't free reservation if it's not ours. */
02236   if (TracksOverlap(GetReservedTrackbits(tile) | TrackToTrackBits(TrackdirToTrack(td)))) return;
02237 
02238   CFollowTrackRail ft(v, GetRailTypeInfo(v->railtype)->compatible_railtypes);
02239   while (ft.Follow(tile, td)) {
02240     tile = ft.m_new_tile;
02241     TrackdirBits bits = ft.m_new_td_bits & TrackBitsToTrackdirBits(GetReservedTrackbits(tile));
02242     td = RemoveFirstTrackdir(&bits);
02243     assert(bits == TRACKDIR_BIT_NONE);
02244 
02245     if (!IsValidTrackdir(td)) break;
02246 
02247     if (IsTileType(tile, MP_RAILWAY)) {
02248       if (HasSignalOnTrackdir(tile, td) && !IsPbsSignal(GetSignalType(tile, TrackdirToTrack(td)))) {
02249         /* Conventional signal along trackdir: remove reservation and stop. */
02250         UnreserveRailTrack(tile, TrackdirToTrack(td));
02251         break;
02252       }
02253       if (HasPbsSignalOnTrackdir(tile, td)) {
02254         if (GetSignalStateByTrackdir(tile, td) == SIGNAL_STATE_RED) {
02255           /* Red PBS signal? Can't be our reservation, would be green then. */
02256           break;
02257         } else {
02258           /* Turn the signal back to red. */
02259           SetSignalStateByTrackdir(tile, td, SIGNAL_STATE_RED);
02260           MarkTileDirtyByTile(tile);
02261         }
02262       } else if (HasSignalOnTrackdir(tile, ReverseTrackdir(td)) && IsOnewaySignal(tile, TrackdirToTrack(td))) {
02263         break;
02264       }
02265     }
02266 
02267     /* Don't free first station/bridge/tunnel if we are on it. */
02268     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);
02269 
02270     free_tile = true;
02271   }
02272 }
02273 
02274 static const byte _initial_tile_subcoord[6][4][3] = {
02275 {{ 15, 8, 1 }, { 0, 0, 0 }, { 0, 8, 5 }, { 0,  0, 0 }},
02276 {{  0, 0, 0 }, { 8, 0, 3 }, { 0, 0, 0 }, { 8, 15, 7 }},
02277 {{  0, 0, 0 }, { 7, 0, 2 }, { 0, 7, 6 }, { 0,  0, 0 }},
02278 {{ 15, 8, 2 }, { 0, 0, 0 }, { 0, 0, 0 }, { 8, 15, 6 }},
02279 {{ 15, 7, 0 }, { 8, 0, 4 }, { 0, 0, 0 }, { 0,  0, 0 }},
02280 {{  0, 0, 0 }, { 0, 0, 0 }, { 0, 8, 4 }, { 7, 15, 0 }},
02281 };
02282 
02295 static Track DoTrainPathfind(const Train *v, TileIndex tile, DiagDirection enterdir, TrackBits tracks, bool &path_found, bool do_track_reservation, PBSTileInfo *dest)
02296 {
02297   switch (_settings_game.pf.pathfinder_for_trains) {
02298     case VPF_NPF: return NPFTrainChooseTrack(v, tile, enterdir, tracks, path_found, do_track_reservation, dest);
02299     case VPF_YAPF: return YapfTrainChooseTrack(v, tile, enterdir, tracks, path_found, do_track_reservation, dest);
02300 
02301     default: NOT_REACHED();
02302   }
02303 }
02304 
02310 static PBSTileInfo ExtendTrainReservation(const Train *v, TrackBits *new_tracks, DiagDirection *enterdir)
02311 {
02312   PBSTileInfo origin = FollowTrainReservation(v);
02313 
02314   CFollowTrackRail ft(v);
02315 
02316   TileIndex tile = origin.tile;
02317   Trackdir  cur_td = origin.trackdir;
02318   while (ft.Follow(tile, cur_td)) {
02319     if (KillFirstBit(ft.m_new_td_bits) == TRACKDIR_BIT_NONE) {
02320       /* Possible signal tile. */
02321       if (HasOnewaySignalBlockingTrackdir(ft.m_new_tile, FindFirstTrackdir(ft.m_new_td_bits))) break;
02322     }
02323 
02324     if (_settings_game.pf.forbid_90_deg) {
02325       ft.m_new_td_bits &= ~TrackdirCrossesTrackdirs(ft.m_old_td);
02326       if (ft.m_new_td_bits == TRACKDIR_BIT_NONE) break;
02327     }
02328 
02329     /* Station, depot or waypoint are a possible target. */
02330     bool target_seen = ft.m_is_station || (IsTileType(ft.m_new_tile, MP_RAILWAY) && !IsPlainRail(ft.m_new_tile));
02331     if (target_seen || KillFirstBit(ft.m_new_td_bits) != TRACKDIR_BIT_NONE) {
02332       /* Choice found or possible target encountered.
02333        * On finding a possible target, we need to stop and let the pathfinder handle the
02334        * remaining path. This is because we don't know if this target is in one of our
02335        * orders, so we might cause pathfinding to fail later on if we find a choice.
02336        * This failure would cause a bogous call to TryReserveSafePath which might reserve
02337        * a wrong path not leading to our next destination. */
02338       if (HasReservedTracks(ft.m_new_tile, TrackdirBitsToTrackBits(TrackdirReachesTrackdirs(ft.m_old_td)))) break;
02339 
02340       /* If we did skip some tiles, backtrack to the first skipped tile so the pathfinder
02341        * actually starts its search at the first unreserved tile. */
02342       if (ft.m_tiles_skipped != 0) ft.m_new_tile -= TileOffsByDiagDir(ft.m_exitdir) * ft.m_tiles_skipped;
02343 
02344       /* Choice found, path valid but not okay. Save info about the choice tile as well. */
02345       if (new_tracks != NULL) *new_tracks = TrackdirBitsToTrackBits(ft.m_new_td_bits);
02346       if (enterdir != NULL) *enterdir = ft.m_exitdir;
02347       return PBSTileInfo(ft.m_new_tile, ft.m_old_td, false);
02348     }
02349 
02350     tile = ft.m_new_tile;
02351     cur_td = FindFirstTrackdir(ft.m_new_td_bits);
02352 
02353     if (IsSafeWaitingPosition(v, tile, cur_td, true, _settings_game.pf.forbid_90_deg)) {
02354       bool wp_free = IsWaitingPositionFree(v, tile, cur_td, _settings_game.pf.forbid_90_deg);
02355       if (!(wp_free && TryReserveRailTrack(tile, TrackdirToTrack(cur_td)))) break;
02356       /* Safe position is all good, path valid and okay. */
02357       return PBSTileInfo(tile, cur_td, true);
02358     }
02359 
02360     if (!TryReserveRailTrack(tile, TrackdirToTrack(cur_td))) break;
02361   }
02362 
02363   if (ft.m_err == CFollowTrackRail::EC_OWNER || ft.m_err == CFollowTrackRail::EC_NO_WAY) {
02364     /* End of line, path valid and okay. */
02365     return PBSTileInfo(ft.m_old_tile, ft.m_old_td, true);
02366   }
02367 
02368   /* Sorry, can't reserve path, back out. */
02369   tile = origin.tile;
02370   cur_td = origin.trackdir;
02371   TileIndex stopped = ft.m_old_tile;
02372   Trackdir  stopped_td = ft.m_old_td;
02373   while (tile != stopped || cur_td != stopped_td) {
02374     if (!ft.Follow(tile, cur_td)) break;
02375 
02376     if (_settings_game.pf.forbid_90_deg) {
02377       ft.m_new_td_bits &= ~TrackdirCrossesTrackdirs(ft.m_old_td);
02378       assert(ft.m_new_td_bits != TRACKDIR_BIT_NONE);
02379     }
02380     assert(KillFirstBit(ft.m_new_td_bits) == TRACKDIR_BIT_NONE);
02381 
02382     tile = ft.m_new_tile;
02383     cur_td = FindFirstTrackdir(ft.m_new_td_bits);
02384 
02385     UnreserveRailTrack(tile, TrackdirToTrack(cur_td));
02386   }
02387 
02388   /* Path invalid. */
02389   return PBSTileInfo();
02390 }
02391 
02402 static bool TryReserveSafeTrack(const Train *v, TileIndex tile, Trackdir td, bool override_tailtype)
02403 {
02404   switch (_settings_game.pf.pathfinder_for_trains) {
02405     case VPF_NPF: return NPFTrainFindNearestSafeTile(v, tile, td, override_tailtype);
02406     case VPF_YAPF: return YapfTrainFindNearestSafeTile(v, tile, td, override_tailtype);
02407 
02408     default: NOT_REACHED();
02409   }
02410 }
02411 
02413 class VehicleOrderSaver {
02414 private:
02415   Train          *v;
02416   Order          old_order;
02417   TileIndex      old_dest_tile;
02418   StationID      old_last_station_visited;
02419   VehicleOrderID index;
02420   bool           suppress_implicit_orders;
02421 
02422 public:
02423   VehicleOrderSaver(Train *_v) :
02424     v(_v),
02425     old_order(_v->current_order),
02426     old_dest_tile(_v->dest_tile),
02427     old_last_station_visited(_v->last_station_visited),
02428     index(_v->cur_real_order_index),
02429     suppress_implicit_orders(HasBit(_v->gv_flags, GVF_SUPPRESS_IMPLICIT_ORDERS))
02430   {
02431   }
02432 
02433   ~VehicleOrderSaver()
02434   {
02435     this->v->current_order = this->old_order;
02436     this->v->dest_tile = this->old_dest_tile;
02437     this->v->last_station_visited = this->old_last_station_visited;
02438     SB(this->v->gv_flags, GVF_SUPPRESS_IMPLICIT_ORDERS, 1, suppress_implicit_orders ? 1: 0);
02439   }
02440 
02446   bool SwitchToNextOrder(bool skip_first)
02447   {
02448     if (this->v->GetNumOrders() == 0) return false;
02449 
02450     if (skip_first) ++this->index;
02451 
02452     int depth = 0;
02453 
02454     do {
02455       /* Wrap around. */
02456       if (this->index >= this->v->GetNumOrders()) this->index = 0;
02457 
02458       Order *order = this->v->GetOrder(this->index);
02459       assert(order != NULL);
02460 
02461       switch (order->GetType()) {
02462         case OT_GOTO_DEPOT:
02463           /* Skip service in depot orders when the train doesn't need service. */
02464           if ((order->GetDepotOrderType() & ODTFB_SERVICE) && !this->v->NeedsServicing()) break;
02465         case OT_GOTO_STATION:
02466         case OT_GOTO_WAYPOINT:
02467           this->v->current_order = *order;
02468           return UpdateOrderDest(this->v, order, 0, true);
02469         case OT_CONDITIONAL: {
02470           VehicleOrderID next = ProcessConditionalOrder(order, this->v);
02471           if (next != INVALID_VEH_ORDER_ID) {
02472             depth++;
02473             this->index = next;
02474             /* Don't increment next, so no break here. */
02475             continue;
02476           }
02477           break;
02478         }
02479         default:
02480           break;
02481       }
02482       /* Don't increment inside the while because otherwise conditional
02483        * orders can lead to an infinite loop. */
02484       ++this->index;
02485       depth++;
02486     } while (this->index != this->v->cur_real_order_index && depth < this->v->GetNumOrders());
02487 
02488     return false;
02489   }
02490 };
02491 
02492 /* choose a track */
02493 static Track ChooseTrainTrack(Train *v, TileIndex tile, DiagDirection enterdir, TrackBits tracks, bool force_res, bool *got_reservation, bool mark_stuck)
02494 {
02495   Track best_track = INVALID_TRACK;
02496   bool do_track_reservation = _settings_game.pf.reserve_paths || force_res;
02497   bool changed_signal = false;
02498 
02499   assert((tracks & ~TRACK_BIT_MASK) == 0);
02500 
02501   if (got_reservation != NULL) *got_reservation = false;
02502 
02503   /* Don't use tracks here as the setting to forbid 90 deg turns might have been switched between reservation and now. */
02504   TrackBits res_tracks = (TrackBits)(GetReservedTrackbits(tile) & DiagdirReachesTracks(enterdir));
02505   /* Do we have a suitable reserved track? */
02506   if (res_tracks != TRACK_BIT_NONE) return FindFirstTrack(res_tracks);
02507 
02508   /* Quick return in case only one possible track is available */
02509   if (KillFirstBit(tracks) == TRACK_BIT_NONE) {
02510     Track track = FindFirstTrack(tracks);
02511     /* We need to check for signals only here, as a junction tile can't have signals. */
02512     if (track != INVALID_TRACK && HasPbsSignalOnTrackdir(tile, TrackEnterdirToTrackdir(track, enterdir))) {
02513       do_track_reservation = true;
02514       changed_signal = true;
02515       SetSignalStateByTrackdir(tile, TrackEnterdirToTrackdir(track, enterdir), SIGNAL_STATE_GREEN);
02516     } else if (!do_track_reservation) {
02517       return track;
02518     }
02519     best_track = track;
02520   }
02521 
02522   PBSTileInfo   res_dest(tile, INVALID_TRACKDIR, false);
02523   DiagDirection dest_enterdir = enterdir;
02524   if (do_track_reservation) {
02525     res_dest = ExtendTrainReservation(v, &tracks, &dest_enterdir);
02526     if (res_dest.tile == INVALID_TILE) {
02527       /* Reservation failed? */
02528       if (mark_stuck) MarkTrainAsStuck(v);
02529       if (changed_signal) SetSignalStateByTrackdir(tile, TrackEnterdirToTrackdir(best_track, enterdir), SIGNAL_STATE_RED);
02530       return FindFirstTrack(tracks);
02531     }
02532     if (res_dest.okay) {
02533       /* Got a valid reservation that ends at a safe target, quick exit. */
02534       if (got_reservation != NULL) *got_reservation = true;
02535       if (changed_signal) MarkTileDirtyByTile(tile);
02536       TryReserveRailTrack(v->tile, TrackdirToTrack(v->GetVehicleTrackdir()));
02537       return best_track;
02538     }
02539 
02540     /* Check if the train needs service here, so it has a chance to always find a depot.
02541      * Also check if the current order is a service order so we don't reserve a path to
02542      * the destination but instead to the next one if service isn't needed. */
02543     CheckIfTrainNeedsService(v);
02544     if (v->current_order.IsType(OT_DUMMY) || v->current_order.IsType(OT_CONDITIONAL) || v->current_order.IsType(OT_GOTO_DEPOT)) ProcessOrders(v);
02545   }
02546 
02547   /* Save the current train order. The destructor will restore the old order on function exit. */
02548   VehicleOrderSaver orders(v);
02549 
02550   /* If the current tile is the destination of the current order and
02551    * a reservation was requested, advance to the next order.
02552    * Don't advance on a depot order as depots are always safe end points
02553    * for a path and no look-ahead is necessary. This also avoids a
02554    * problem with depot orders not part of the order list when the
02555    * order list itself is empty. */
02556   if (v->current_order.IsType(OT_LEAVESTATION)) {
02557     orders.SwitchToNextOrder(false);
02558   } else if (v->current_order.IsType(OT_LOADING) || (!v->current_order.IsType(OT_GOTO_DEPOT) && (
02559       v->current_order.IsType(OT_GOTO_STATION) ?
02560       IsRailStationTile(v->tile) && v->current_order.GetDestination() == GetStationIndex(v->tile) :
02561       v->tile == v->dest_tile))) {
02562     orders.SwitchToNextOrder(true);
02563   }
02564 
02565   if (res_dest.tile != INVALID_TILE && !res_dest.okay) {
02566     /* Pathfinders are able to tell that route was only 'guessed'. */
02567     bool      path_found = true;
02568     TileIndex new_tile = res_dest.tile;
02569 
02570     Track next_track = DoTrainPathfind(v, new_tile, dest_enterdir, tracks, path_found, do_track_reservation, &res_dest);
02571     if (new_tile == tile) best_track = next_track;
02572     v->HandlePathfindingResult(path_found);
02573   }
02574 
02575   /* No track reservation requested -> finished. */
02576   if (!do_track_reservation) return best_track;
02577 
02578   /* A path was found, but could not be reserved. */
02579   if (res_dest.tile != INVALID_TILE && !res_dest.okay) {
02580     if (mark_stuck) MarkTrainAsStuck(v);
02581     FreeTrainTrackReservation(v);
02582     return best_track;
02583   }
02584 
02585   /* No possible reservation target found, we are probably lost. */
02586   if (res_dest.tile == INVALID_TILE) {
02587     /* Try to find any safe destination. */
02588     PBSTileInfo origin = FollowTrainReservation(v);
02589     if (TryReserveSafeTrack(v, origin.tile, origin.trackdir, false)) {
02590       TrackBits res = GetReservedTrackbits(tile) & DiagdirReachesTracks(enterdir);
02591       best_track = FindFirstTrack(res);
02592       TryReserveRailTrack(v->tile, TrackdirToTrack(v->GetVehicleTrackdir()));
02593       if (got_reservation != NULL) *got_reservation = true;
02594       if (changed_signal) MarkTileDirtyByTile(tile);
02595     } else {
02596       FreeTrainTrackReservation(v);
02597       if (mark_stuck) MarkTrainAsStuck(v);
02598     }
02599     return best_track;
02600   }
02601 
02602   if (got_reservation != NULL) *got_reservation = true;
02603 
02604   /* Reservation target found and free, check if it is safe. */
02605   while (!IsSafeWaitingPosition(v, res_dest.tile, res_dest.trackdir, true, _settings_game.pf.forbid_90_deg)) {
02606     /* Extend reservation until we have found a safe position. */
02607     DiagDirection exitdir = TrackdirToExitdir(res_dest.trackdir);
02608     TileIndex     next_tile = TileAddByDiagDir(res_dest.tile, exitdir);
02609     TrackBits     reachable = TrackdirBitsToTrackBits((TrackdirBits)(GetTileTrackStatus(next_tile, TRANSPORT_RAIL, 0))) & DiagdirReachesTracks(exitdir);
02610     if (_settings_game.pf.forbid_90_deg) {
02611       reachable &= ~TrackCrossesTracks(TrackdirToTrack(res_dest.trackdir));
02612     }
02613 
02614     /* Get next order with destination. */
02615     if (orders.SwitchToNextOrder(true)) {
02616       PBSTileInfo cur_dest;
02617       bool path_found;
02618       DoTrainPathfind(v, next_tile, exitdir, reachable, path_found, true, &cur_dest);
02619       if (cur_dest.tile != INVALID_TILE) {
02620         res_dest = cur_dest;
02621         if (res_dest.okay) continue;
02622         /* Path found, but could not be reserved. */
02623         FreeTrainTrackReservation(v);
02624         if (mark_stuck) MarkTrainAsStuck(v);
02625         if (got_reservation != NULL) *got_reservation = false;
02626         changed_signal = false;
02627         break;
02628       }
02629     }
02630     /* No order or no safe position found, try any position. */
02631     if (!TryReserveSafeTrack(v, res_dest.tile, res_dest.trackdir, true)) {
02632       FreeTrainTrackReservation(v);
02633       if (mark_stuck) MarkTrainAsStuck(v);
02634       if (got_reservation != NULL) *got_reservation = false;
02635       changed_signal = false;
02636     }
02637     break;
02638   }
02639 
02640   TryReserveRailTrack(v->tile, TrackdirToTrack(v->GetVehicleTrackdir()));
02641 
02642   if (changed_signal) MarkTileDirtyByTile(tile);
02643 
02644   return best_track;
02645 }
02646 
02655 bool TryPathReserve(Train *v, bool mark_as_stuck, bool first_tile_okay)
02656 {
02657   assert(v->IsFrontEngine());
02658 
02659   /* We have to handle depots specially as the track follower won't look
02660    * at the depot tile itself but starts from the next tile. If we are still
02661    * inside the depot, a depot reservation can never be ours. */
02662   if (v->track == TRACK_BIT_DEPOT) {
02663     if (HasDepotReservation(v->tile)) {
02664       if (mark_as_stuck) MarkTrainAsStuck(v);
02665       return false;
02666     } else {
02667       /* Depot not reserved, but the next tile might be. */
02668       TileIndex next_tile = TileAddByDiagDir(v->tile, GetRailDepotDirection(v->tile));
02669       if (HasReservedTracks(next_tile, DiagdirReachesTracks(GetRailDepotDirection(v->tile)))) return false;
02670     }
02671   }
02672 
02673   Vehicle *other_train = NULL;
02674   PBSTileInfo origin = FollowTrainReservation(v, &other_train);
02675   /* The path we are driving on is already blocked by some other train.
02676    * This can only happen in certain situations when mixing path and
02677    * block signals or when changing tracks and/or signals.
02678    * Exit here as doing any further reservations will probably just
02679    * make matters worse. */
02680   if (other_train != NULL && other_train->index != v->index) {
02681     if (mark_as_stuck) MarkTrainAsStuck(v);
02682     return false;
02683   }
02684   /* If we have a reserved path and the path ends at a safe tile, we are finished already. */
02685   if (origin.okay && (v->tile != origin.tile || first_tile_okay)) {
02686     /* Can't be stuck then. */
02687     if (HasBit(v->flags, VRF_TRAIN_STUCK)) SetWindowWidgetDirty(WC_VEHICLE_VIEW, v->index, WID_VV_START_STOP);
02688     ClrBit(v->flags, VRF_TRAIN_STUCK);
02689     return true;
02690   }
02691 
02692   /* If we are in a depot, tentatively reserve the depot. */
02693   if (v->track == TRACK_BIT_DEPOT) {
02694     SetDepotReservation(v->tile, true);
02695     if (_settings_client.gui.show_track_reservation) MarkTileDirtyByTile(v->tile);
02696   }
02697 
02698   DiagDirection exitdir = TrackdirToExitdir(origin.trackdir);
02699   TileIndex     new_tile = TileAddByDiagDir(origin.tile, exitdir);
02700   TrackBits     reachable = TrackdirBitsToTrackBits(TrackStatusToTrackdirBits(GetTileTrackStatus(new_tile, TRANSPORT_RAIL, 0)) & DiagdirReachesTrackdirs(exitdir));
02701 
02702   if (_settings_game.pf.forbid_90_deg) reachable &= ~TrackCrossesTracks(TrackdirToTrack(origin.trackdir));
02703 
02704   bool res_made = false;
02705   ChooseTrainTrack(v, new_tile, exitdir, reachable, true, &res_made, mark_as_stuck);
02706 
02707   if (!res_made) {
02708     /* Free the depot reservation as well. */
02709     if (v->track == TRACK_BIT_DEPOT) SetDepotReservation(v->tile, false);
02710     return false;
02711   }
02712 
02713   if (HasBit(v->flags, VRF_TRAIN_STUCK)) {
02714     v->wait_counter = 0;
02715     SetWindowWidgetDirty(WC_VEHICLE_VIEW, v->index, WID_VV_START_STOP);
02716   }
02717   ClrBit(v->flags, VRF_TRAIN_STUCK);
02718   return true;
02719 }
02720 
02721 
02722 static bool CheckReverseTrain(const Train *v)
02723 {
02724   if (_settings_game.difficulty.line_reverse_mode != 0 ||
02725       v->track == TRACK_BIT_DEPOT || v->track == TRACK_BIT_WORMHOLE ||
02726       !(v->direction & 1)) {
02727     return false;
02728   }
02729 
02730   assert(v->track != TRACK_BIT_NONE);
02731 
02732   switch (_settings_game.pf.pathfinder_for_trains) {
02733     case VPF_NPF: return NPFTrainCheckReverse(v);
02734     case VPF_YAPF: return YapfTrainCheckReverse(v);
02735 
02736     default: NOT_REACHED();
02737   }
02738 }
02739 
02745 TileIndex Train::GetOrderStationLocation(StationID station)
02746 {
02747   if (station == this->last_station_visited) this->last_station_visited = INVALID_STATION;
02748 
02749   const Station *st = Station::Get(station);
02750   if (!(st->facilities & FACIL_TRAIN)) {
02751     /* The destination station has no trainstation tiles. */
02752     this->IncrementRealOrderIndex();
02753     return 0;
02754   }
02755 
02756   return st->xy;
02757 }
02758 
02760 void Train::MarkDirty()
02761 {
02762   Train *v = this;
02763   do {
02764     v->UpdateViewport(false, false);
02765   } while ((v = v->Next()) != NULL);
02766 
02767   /* need to update acceleration and cached values since the goods on the train changed. */
02768   this->CargoChanged();
02769   this->UpdateAcceleration();
02770 }
02771 
02779 int Train::UpdateSpeed()
02780 {
02781   switch (_settings_game.vehicle.train_acceleration_model) {
02782     default: NOT_REACHED();
02783     case AM_ORIGINAL:
02784       return this->DoUpdateSpeed(this->acceleration * (this->GetAccelerationStatus() == AS_BRAKE ? -4 : 2), 0, min(this->gcache.cached_max_track_speed, this->current_order.max_speed));
02785 
02786     case AM_REALISTIC:
02787       return this->DoUpdateSpeed(this->GetAcceleration(), this->GetAccelerationStatus() == AS_BRAKE ? 0 : 2, this->GetCurrentMaxSpeed());
02788   }
02789 }
02790 
02796 static void TrainEnterStation(Train *v, StationID station)
02797 {
02798   v->last_station_visited = station;
02799 
02800   /* check if a train ever visited this station before */
02801   Station *st = Station::Get(station);
02802   if (!(st->had_vehicle_of_type & HVOT_TRAIN)) {
02803     st->had_vehicle_of_type |= HVOT_TRAIN;
02804     SetDParam(0, st->index);
02805     AddVehicleNewsItem(
02806       STR_NEWS_FIRST_TRAIN_ARRIVAL,
02807       v->owner == _local_company ? NT_ARRIVAL_COMPANY : NT_ARRIVAL_OTHER,
02808       v->index,
02809       st->index
02810     );
02811     AI::NewEvent(v->owner, new ScriptEventStationFirstVehicle(st->index, v->index));
02812     Game::NewEvent(new ScriptEventStationFirstVehicle(st->index, v->index));
02813   }
02814 
02815   v->force_proceed = TFP_NONE;
02816   SetWindowDirty(WC_VEHICLE_VIEW, v->index);
02817 
02818   v->BeginLoading();
02819 
02820   TriggerStationRandomisation(st, v->tile, SRT_TRAIN_ARRIVES);
02821   TriggerStationAnimation(st, v->tile, SAT_TRAIN_ARRIVES);
02822 }
02823 
02824 /* Check if the vehicle is compatible with the specified tile */
02825 static inline bool CheckCompatibleRail(const Train *v, TileIndex tile)
02826 {
02827   return IsTileOwner(tile, v->owner) &&
02828       (!v->IsFrontEngine() || HasBit(v->compatible_railtypes, GetRailType(tile)));
02829 }
02830 
02832 struct AccelerationSlowdownParams {
02833   byte small_turn; 
02834   byte large_turn; 
02835   byte z_up;       
02836   byte z_down;     
02837 };
02838 
02840 static const AccelerationSlowdownParams _accel_slowdown[] = {
02841   /* normal accel */
02842   {256 / 4, 256 / 2, 256 / 4, 2}, 
02843   {256 / 4, 256 / 2, 256 / 4, 2}, 
02844   {0,       256 / 2, 256 / 4, 2}, 
02845 };
02846 
02852 static inline void AffectSpeedByZChange(Train *v, int old_z)
02853 {
02854   if (old_z == v->z_pos || _settings_game.vehicle.train_acceleration_model != AM_ORIGINAL) return;
02855 
02856   const AccelerationSlowdownParams *asp = &_accel_slowdown[GetRailTypeInfo(v->railtype)->acceleration_type];
02857 
02858   if (old_z < v->z_pos) {
02859     v->cur_speed -= (v->cur_speed * asp->z_up >> 8);
02860   } else {
02861     uint16 spd = v->cur_speed + asp->z_down;
02862     if (spd <= v->gcache.cached_max_track_speed) v->cur_speed = spd;
02863   }
02864 }
02865 
02866 static bool TrainMovedChangeSignals(TileIndex tile, DiagDirection dir)
02867 {
02868   if (IsTileType(tile, MP_RAILWAY) &&
02869       GetRailTileType(tile) == RAIL_TILE_SIGNALS) {
02870     TrackdirBits tracks = TrackBitsToTrackdirBits(GetTrackBits(tile)) & DiagdirReachesTrackdirs(dir);
02871     Trackdir trackdir = FindFirstTrackdir(tracks);
02872     if (UpdateSignalsOnSegment(tile,  TrackdirToExitdir(trackdir), GetTileOwner(tile)) == SIGSEG_PBS && HasSignalOnTrackdir(tile, trackdir)) {
02873       /* A PBS block with a non-PBS signal facing us? */
02874       if (!IsPbsSignal(GetSignalType(tile, TrackdirToTrack(trackdir)))) return true;
02875     }
02876   }
02877   return false;
02878 }
02879 
02881 void Train::ReserveTrackUnderConsist() const
02882 {
02883   for (const Train *u = this; u != NULL; u = u->Next()) {
02884     switch (u->track) {
02885       case TRACK_BIT_WORMHOLE:
02886         TryReserveRailTrack(u->tile, DiagDirToDiagTrack(GetTunnelBridgeDirection(u->tile)));
02887         break;
02888       case TRACK_BIT_DEPOT:
02889         break;
02890       default:
02891         TryReserveRailTrack(u->tile, TrackBitsToTrack(u->track));
02892         break;
02893     }
02894   }
02895 }
02896 
02903 uint Train::Crash(bool flooded)
02904 {
02905   uint pass = 0;
02906   if (this->IsFrontEngine()) {
02907     pass += 2; // driver
02908 
02909     /* Remove the reserved path in front of the train if it is not stuck.
02910      * Also clear all reserved tracks the train is currently on. */
02911     if (!HasBit(this->flags, VRF_TRAIN_STUCK)) FreeTrainTrackReservation(this);
02912     for (const Train *v = this; v != NULL; v = v->Next()) {
02913       ClearPathReservation(v, v->tile, v->GetVehicleTrackdir());
02914       if (IsTileType(v->tile, MP_TUNNELBRIDGE)) {
02915         /* ClearPathReservation will not free the wormhole exit
02916          * if the train has just entered the wormhole. */
02917         SetTunnelBridgeReservation(GetOtherTunnelBridgeEnd(v->tile), false);
02918       }
02919     }
02920 
02921     /* we may need to update crossing we were approaching,
02922      * but must be updated after the train has been marked crashed */
02923     TileIndex crossing = TrainApproachingCrossingTile(this);
02924     if (crossing != INVALID_TILE) UpdateLevelCrossing(crossing);
02925 
02926     /* Remove the loading indicators (if any) */
02927     HideFillingPercent(&this->fill_percent_te_id);
02928   }
02929 
02930   pass += this->GroundVehicleBase::Crash(flooded);
02931 
02932   this->crash_anim_pos = flooded ? 4000 : 1; // max 4440, disappear pretty fast when flooded
02933   return pass;
02934 }
02935 
02942 static uint TrainCrashed(Train *v)
02943 {
02944   uint num = 0;
02945 
02946   /* do not crash train twice */
02947   if (!(v->vehstatus & VS_CRASHED)) {
02948     num = v->Crash();
02949     AI::NewEvent(v->owner, new ScriptEventVehicleCrashed(v->index, v->tile, ScriptEventVehicleCrashed::CRASH_TRAIN));
02950     Game::NewEvent(new ScriptEventVehicleCrashed(v->index, v->tile, ScriptEventVehicleCrashed::CRASH_TRAIN));
02951   }
02952 
02953   /* Try to re-reserve track under already crashed train too.
02954    * Crash() clears the reservation! */
02955   v->ReserveTrackUnderConsist();
02956 
02957   return num;
02958 }
02959 
02961 struct TrainCollideChecker {
02962   Train *v; 
02963   uint num; 
02964 };
02965 
02972 static Vehicle *FindTrainCollideEnum(Vehicle *v, void *data)
02973 {
02974   TrainCollideChecker *tcc = (TrainCollideChecker*)data;
02975 
02976   /* not a train or in depot */
02977   if (v->type != VEH_TRAIN || Train::From(v)->track == TRACK_BIT_DEPOT) return NULL;
02978 
02979   /* do not crash into trains of another company. */
02980   if (v->owner != tcc->v->owner) return NULL;
02981 
02982   /* get first vehicle now to make most usual checks faster */
02983   Train *coll = Train::From(v)->First();
02984 
02985   /* can't collide with own wagons */
02986   if (coll == tcc->v) return NULL;
02987 
02988   int x_diff = v->x_pos - tcc->v->x_pos;
02989   int y_diff = v->y_pos - tcc->v->y_pos;
02990 
02991   /* Do fast calculation to check whether trains are not in close vicinity
02992    * and quickly reject trains distant enough for any collision.
02993    * Differences are shifted by 7, mapping range [-7 .. 8] into [0 .. 15]
02994    * Differences are then ORed and then we check for any higher bits */
02995   uint hash = (y_diff + 7) | (x_diff + 7);
02996   if (hash & ~15) return NULL;
02997 
02998   /* Slower check using multiplication */
02999   int min_diff = (Train::From(v)->gcache.cached_veh_length + 1) / 2 + (tcc->v->gcache.cached_veh_length + 1) / 2 - 1;
03000   if (x_diff * x_diff + y_diff * y_diff > min_diff * min_diff) return NULL;
03001 
03002   /* Happens when there is a train under bridge next to bridge head */
03003   if (abs(v->z_pos - tcc->v->z_pos) > 5) return NULL;
03004 
03005   /* crash both trains */
03006   tcc->num += TrainCrashed(tcc->v);
03007   tcc->num += TrainCrashed(coll);
03008 
03009   return NULL; // continue searching
03010 }
03011 
03019 static bool CheckTrainCollision(Train *v)
03020 {
03021   /* can't collide in depot */
03022   if (v->track == TRACK_BIT_DEPOT) return false;
03023 
03024   assert(v->track == TRACK_BIT_WORMHOLE || TileVirtXY(v->x_pos, v->y_pos) == v->tile);
03025 
03026   TrainCollideChecker tcc;
03027   tcc.v = v;
03028   tcc.num = 0;
03029 
03030   /* find colliding vehicles */
03031   if (v->track == TRACK_BIT_WORMHOLE) {
03032     FindVehicleOnPos(v->tile, &tcc, FindTrainCollideEnum);
03033     FindVehicleOnPos(GetOtherTunnelBridgeEnd(v->tile), &tcc, FindTrainCollideEnum);
03034   } else {
03035     FindVehicleOnPosXY(v->x_pos, v->y_pos, &tcc, FindTrainCollideEnum);
03036   }
03037 
03038   /* any dead -> no crash */
03039   if (tcc.num == 0) return false;
03040 
03041   SetDParam(0, tcc.num);
03042   AddVehicleNewsItem(STR_NEWS_TRAIN_CRASH, NT_ACCIDENT, v->index);
03043 
03044   ModifyStationRatingAround(v->tile, v->owner, -160, 30);
03045   if (_settings_client.sound.disaster) SndPlayVehicleFx(SND_13_BIG_CRASH, v);
03046   return true;
03047 }
03048 
03049 static Vehicle *CheckTrainAtSignal(Vehicle *v, void *data)
03050 {
03051   if (v->type != VEH_TRAIN || (v->vehstatus & VS_CRASHED)) return NULL;
03052 
03053   Train *t = Train::From(v);
03054   DiagDirection exitdir = *(DiagDirection *)data;
03055 
03056   /* not front engine of a train, inside wormhole or depot, crashed */
03057   if (!t->IsFrontEngine() || !(t->track & TRACK_BIT_MASK)) return NULL;
03058 
03059   if (t->cur_speed > 5 || TrainExitDir(t->direction, t->track) != exitdir) return NULL;
03060 
03061   return t;
03062 }
03063 
03071 bool TrainController(Train *v, Vehicle *nomove, bool reverse)
03072 {
03073   Train *first = v->First();
03074   Train *prev;
03075   bool direction_changed = false; // has direction of any part changed?
03076 
03077   /* For every vehicle after and including the given vehicle */
03078   for (prev = v->Previous(); v != nomove; prev = v, v = v->Next()) {
03079     DiagDirection enterdir = DIAGDIR_BEGIN;
03080     bool update_signals_crossing = false; // will we update signals or crossing state?
03081 
03082     GetNewVehiclePosResult gp = GetNewVehiclePos(v);
03083     if (v->track != TRACK_BIT_WORMHOLE) {
03084       /* Not inside tunnel */
03085       if (gp.old_tile == gp.new_tile) {
03086         /* Staying in the old tile */
03087         if (v->track == TRACK_BIT_DEPOT) {
03088           /* Inside depot */
03089           gp.x = v->x_pos;
03090           gp.y = v->y_pos;
03091         } else {
03092           /* Not inside depot */
03093 
03094           /* Reverse when we are at the end of the track already, do not move to the new position */
03095           if (v->IsFrontEngine() && !TrainCheckIfLineEnds(v, reverse)) return false;
03096 
03097           uint32 r = VehicleEnterTile(v, gp.new_tile, gp.x, gp.y);
03098           if (HasBit(r, VETS_CANNOT_ENTER)) {
03099             goto invalid_rail;
03100           }
03101           if (HasBit(r, VETS_ENTERED_STATION)) {
03102             /* The new position is the end of the platform */
03103             TrainEnterStation(v, r >> VETS_STATION_ID_OFFSET);
03104           }
03105         }
03106       } else {
03107         /* A new tile is about to be entered. */
03108 
03109         /* Determine what direction we're entering the new tile from */
03110         enterdir = DiagdirBetweenTiles(gp.old_tile, gp.new_tile);
03111         assert(IsValidDiagDirection(enterdir));
03112 
03113         /* Get the status of the tracks in the new tile and mask
03114          * away the bits that aren't reachable. */
03115         TrackStatus ts = GetTileTrackStatus(gp.new_tile, TRANSPORT_RAIL, 0, ReverseDiagDir(enterdir));
03116         TrackdirBits reachable_trackdirs = DiagdirReachesTrackdirs(enterdir);
03117 
03118         TrackdirBits trackdirbits = TrackStatusToTrackdirBits(ts) & reachable_trackdirs;
03119         TrackBits red_signals = TrackdirBitsToTrackBits(TrackStatusToRedSignals(ts) & reachable_trackdirs);
03120 
03121         TrackBits bits = TrackdirBitsToTrackBits(trackdirbits);
03122         if (_settings_game.pf.forbid_90_deg && prev == NULL) {
03123           /* We allow wagons to make 90 deg turns, because forbid_90_deg
03124            * can be switched on halfway a turn */
03125           bits &= ~TrackCrossesTracks(FindFirstTrack(v->track));
03126         }
03127 
03128         if (bits == TRACK_BIT_NONE) goto invalid_rail;
03129 
03130         /* Check if the new tile constrains tracks that are compatible
03131          * with the current train, if not, bail out. */
03132         if (!CheckCompatibleRail(v, gp.new_tile)) goto invalid_rail;
03133 
03134         TrackBits chosen_track;
03135         if (prev == NULL) {
03136           /* Currently the locomotive is active. Determine which one of the
03137            * available tracks to choose */
03138           chosen_track = TrackToTrackBits(ChooseTrainTrack(v, gp.new_tile, enterdir, bits, false, NULL, true));
03139           assert(chosen_track & (bits | GetReservedTrackbits(gp.new_tile)));
03140 
03141           if (v->force_proceed != TFP_NONE && IsPlainRailTile(gp.new_tile) && HasSignals(gp.new_tile)) {
03142             /* For each signal we find decrease the counter by one.
03143              * We start at two, so the first signal we pass decreases
03144              * this to one, then if we reach the next signal it is
03145              * decreased to zero and we won't pass that new signal. */
03146             Trackdir dir = FindFirstTrackdir(trackdirbits);
03147             if (GetSignalType(gp.new_tile, TrackdirToTrack(dir)) != SIGTYPE_PBS ||
03148                 !HasSignalOnTrackdir(gp.new_tile, ReverseTrackdir(dir))) {
03149               /* However, we do not want to be stopped by PBS signals
03150                * entered via the back. */
03151               v->force_proceed = (v->force_proceed == TFP_SIGNAL) ? TFP_STUCK : TFP_NONE;
03152               SetWindowDirty(WC_VEHICLE_VIEW, v->index);
03153             }
03154           }
03155 
03156           /* Check if it's a red signal and that force proceed is not clicked. */
03157           if ((red_signals & chosen_track) && v->force_proceed == TFP_NONE) {
03158             /* In front of a red signal */
03159             Trackdir i = FindFirstTrackdir(trackdirbits);
03160 
03161             /* Don't handle stuck trains here. */
03162             if (HasBit(v->flags, VRF_TRAIN_STUCK)) return false;
03163 
03164             if (!HasSignalOnTrackdir(gp.new_tile, ReverseTrackdir(i))) {
03165               v->cur_speed = 0;
03166               v->subspeed = 0;
03167               v->progress = 255 - 100;
03168               if (!_settings_game.pf.reverse_at_signals || ++v->wait_counter < _settings_game.pf.wait_oneway_signal * 20) return false;
03169             } else if (HasSignalOnTrackdir(gp.new_tile, i)) {
03170               v->cur_speed = 0;
03171               v->subspeed = 0;
03172               v->progress = 255 - 10;
03173               if (!_settings_game.pf.reverse_at_signals || ++v->wait_counter < _settings_game.pf.wait_twoway_signal * 73) {
03174                 DiagDirection exitdir = TrackdirToExitdir(i);
03175                 TileIndex o_tile = TileAddByDiagDir(gp.new_tile, exitdir);
03176 
03177                 exitdir = ReverseDiagDir(exitdir);
03178 
03179                 /* check if a train is waiting on the other side */
03180                 if (!HasVehicleOnPos(o_tile, &exitdir, &CheckTrainAtSignal)) return false;
03181               }
03182             }
03183 
03184             /* If we would reverse but are currently in a PBS block and
03185              * reversing of stuck trains is disabled, don't reverse.
03186              * This does not apply if the reason for reversing is a one-way
03187              * signal blocking us, because a train would then be stuck forever. */
03188             if (!_settings_game.pf.reverse_at_signals && !HasOnewaySignalBlockingTrackdir(gp.new_tile, i) &&
03189                 UpdateSignalsOnSegment(v->tile, enterdir, v->owner) == SIGSEG_PBS) {
03190               v->wait_counter = 0;
03191               return false;
03192             }
03193             goto reverse_train_direction;
03194           } else {
03195             TryReserveRailTrack(gp.new_tile, TrackBitsToTrack(chosen_track), false);
03196           }
03197         } else {
03198           /* The wagon is active, simply follow the prev vehicle. */
03199           if (prev->tile == gp.new_tile) {
03200             /* Choose the same track as prev */
03201             if (prev->track == TRACK_BIT_WORMHOLE) {
03202               /* Vehicles entering tunnels enter the wormhole earlier than for bridges.
03203                * However, just choose the track into the wormhole. */
03204               assert(IsTunnel(prev->tile));
03205               chosen_track = bits;
03206             } else {
03207               chosen_track = prev->track;
03208             }
03209           } else {
03210             /* Choose the track that leads to the tile where prev is.
03211              * This case is active if 'prev' is already on the second next tile, when 'v' just enters the next tile.
03212              * I.e. when the tile between them has only space for a single vehicle like
03213              *  1) horizontal/vertical track tiles and
03214              *  2) some orientations of tunnel entries, where the vehicle is already inside the wormhole at 8/16 from the tile edge.
03215              *     Is also the train just reversing, the wagon inside the tunnel is 'on' the tile of the opposite tunnel entry.
03216              */
03217             static const TrackBits _connecting_track[DIAGDIR_END][DIAGDIR_END] = {
03218               {TRACK_BIT_X,     TRACK_BIT_LOWER, TRACK_BIT_NONE,  TRACK_BIT_LEFT },
03219               {TRACK_BIT_UPPER, TRACK_BIT_Y,     TRACK_BIT_LEFT,  TRACK_BIT_NONE },
03220               {TRACK_BIT_NONE,  TRACK_BIT_RIGHT, TRACK_BIT_X,     TRACK_BIT_UPPER},
03221               {TRACK_BIT_RIGHT, TRACK_BIT_NONE,  TRACK_BIT_LOWER, TRACK_BIT_Y    }
03222             };
03223             DiagDirection exitdir = DiagdirBetweenTiles(gp.new_tile, prev->tile);
03224             assert(IsValidDiagDirection(exitdir));
03225             chosen_track = _connecting_track[enterdir][exitdir];
03226           }
03227           chosen_track &= bits;
03228         }
03229 
03230         /* Make sure chosen track is a valid track */
03231         assert(
03232             chosen_track == TRACK_BIT_X     || chosen_track == TRACK_BIT_Y ||
03233             chosen_track == TRACK_BIT_UPPER || chosen_track == TRACK_BIT_LOWER ||
03234             chosen_track == TRACK_BIT_LEFT  || chosen_track == TRACK_BIT_RIGHT);
03235 
03236         /* Update XY to reflect the entrance to the new tile, and select the direction to use */
03237         const byte *b = _initial_tile_subcoord[FIND_FIRST_BIT(chosen_track)][enterdir];
03238         gp.x = (gp.x & ~0xF) | b[0];
03239         gp.y = (gp.y & ~0xF) | b[1];
03240         Direction chosen_dir = (Direction)b[2];
03241 
03242         /* Call the landscape function and tell it that the vehicle entered the tile */
03243         uint32 r = VehicleEnterTile(v, gp.new_tile, gp.x, gp.y);
03244         if (HasBit(r, VETS_CANNOT_ENTER)) {
03245           goto invalid_rail;
03246         }
03247 
03248         if (!HasBit(r, VETS_ENTERED_WORMHOLE)) {
03249           Track track = FindFirstTrack(chosen_track);
03250           Trackdir tdir = TrackDirectionToTrackdir(track, chosen_dir);
03251           if (v->IsFrontEngine() && HasPbsSignalOnTrackdir(gp.new_tile, tdir)) {
03252             SetSignalStateByTrackdir(gp.new_tile, tdir, SIGNAL_STATE_RED);
03253             MarkTileDirtyByTile(gp.new_tile);
03254           }
03255 
03256           /* Clear any track reservation when the last vehicle leaves the tile */
03257           if (v->Next() == NULL) ClearPathReservation(v, v->tile, v->GetVehicleTrackdir());
03258 
03259           v->tile = gp.new_tile;
03260 
03261           if (GetTileRailType(gp.new_tile) != GetTileRailType(gp.old_tile)) {
03262             v->First()->ConsistChanged(true);
03263           }
03264 
03265           v->track = chosen_track;
03266           assert(v->track);
03267         }
03268 
03269         /* We need to update signal status, but after the vehicle position hash
03270          * has been updated by UpdateInclination() */
03271         update_signals_crossing = true;
03272 
03273         if (chosen_dir != v->direction) {
03274           if (prev == NULL && _settings_game.vehicle.train_acceleration_model == AM_ORIGINAL) {
03275             const AccelerationSlowdownParams *asp = &_accel_slowdown[GetRailTypeInfo(v->railtype)->acceleration_type];
03276             DirDiff diff = DirDifference(v->direction, chosen_dir);
03277             v->cur_speed -= (diff == DIRDIFF_45RIGHT || diff == DIRDIFF_45LEFT ? asp->small_turn : asp->large_turn) * v->cur_speed >> 8;
03278           }
03279           direction_changed = true;
03280           v->direction = chosen_dir;
03281         }
03282 
03283         if (v->IsFrontEngine()) {
03284           v->wait_counter = 0;
03285 
03286           /* If we are approaching a crossing that is reserved, play the sound now. */
03287           TileIndex crossing = TrainApproachingCrossingTile(v);
03288           if (crossing != INVALID_TILE && HasCrossingReservation(crossing) && _settings_client.sound.new_year) SndPlayTileFx(SND_0E_LEVEL_CROSSING, crossing);
03289 
03290           /* Always try to extend the reservation when entering a tile. */
03291           CheckNextTrainTile(v);
03292         }
03293 
03294         if (HasBit(r, VETS_ENTERED_STATION)) {
03295           /* The new position is the location where we want to stop */
03296           TrainEnterStation(v, r >> VETS_STATION_ID_OFFSET);
03297         }
03298       }
03299     } else {
03300       if (IsTileType(gp.new_tile, MP_TUNNELBRIDGE) && HasBit(VehicleEnterTile(v, gp.new_tile, gp.x, gp.y), VETS_ENTERED_WORMHOLE)) {
03301         /* Perform look-ahead on tunnel exit. */
03302         if (v->IsFrontEngine()) {
03303           TryReserveRailTrack(gp.new_tile, DiagDirToDiagTrack(GetTunnelBridgeDirection(gp.new_tile)));
03304           CheckNextTrainTile(v);
03305         }
03306         /* Prevent v->UpdateInclination() being called with wrong parameters.
03307          * This could happen if the train was reversed inside the tunnel/bridge. */
03308         if (gp.old_tile == gp.new_tile) {
03309           gp.old_tile = GetOtherTunnelBridgeEnd(gp.old_tile);
03310         }
03311       } else {
03312         v->x_pos = gp.x;
03313         v->y_pos = gp.y;
03314         VehicleUpdatePosition(v);
03315         if ((v->vehstatus & VS_HIDDEN) == 0) VehicleUpdateViewport(v, true);
03316         continue;
03317       }
03318     }
03319 
03320     /* update image of train, as well as delta XY */
03321     v->UpdateDeltaXY(v->direction);
03322 
03323     v->x_pos = gp.x;
03324     v->y_pos = gp.y;
03325     VehicleUpdatePosition(v);
03326 
03327     /* update the Z position of the vehicle */
03328     int old_z = v->UpdateInclination(gp.new_tile != gp.old_tile, false);
03329 
03330     if (prev == NULL) {
03331       /* This is the first vehicle in the train */
03332       AffectSpeedByZChange(v, old_z);
03333     }
03334 
03335     if (update_signals_crossing) {
03336       if (v->IsFrontEngine()) {
03337         if (TrainMovedChangeSignals(gp.new_tile, enterdir)) {
03338           /* We are entering a block with PBS signals right now, but
03339            * not through a PBS signal. This means we don't have a
03340            * reservation right now. As a conventional signal will only
03341            * ever be green if no other train is in the block, getting
03342            * a path should always be possible. If the player built
03343            * such a strange network that it is not possible, the train
03344            * will be marked as stuck and the player has to deal with
03345            * the problem. */
03346           if ((!HasReservedTracks(gp.new_tile, v->track) &&
03347               !TryReserveRailTrack(gp.new_tile, FindFirstTrack(v->track))) ||
03348               !TryPathReserve(v)) {
03349             MarkTrainAsStuck(v);
03350           }
03351         }
03352       }
03353 
03354       /* Signals can only change when the first
03355        * (above) or the last vehicle moves. */
03356       if (v->Next() == NULL) {
03357         TrainMovedChangeSignals(gp.old_tile, ReverseDiagDir(enterdir));
03358         if (IsLevelCrossingTile(gp.old_tile)) UpdateLevelCrossing(gp.old_tile);
03359       }
03360     }
03361 
03362     /* Do not check on every tick to save some computing time. */
03363     if (v->IsFrontEngine() && v->tick_counter % _settings_game.pf.path_backoff_interval == 0) CheckNextTrainTile(v);
03364   }
03365 
03366   if (direction_changed) first->tcache.cached_max_curve_speed = first->GetCurveSpeedLimit();
03367 
03368   return true;
03369 
03370 invalid_rail:
03371   /* We've reached end of line?? */
03372   if (prev != NULL) error("Disconnecting train");
03373 
03374 reverse_train_direction:
03375   if (reverse) {
03376     v->wait_counter = 0;
03377     v->cur_speed = 0;
03378     v->subspeed = 0;
03379     ReverseTrainDirection(v);
03380   }
03381 
03382   return false;
03383 }
03384 
03391 static Vehicle *CollectTrackbitsFromCrashedVehiclesEnum(Vehicle *v, void *data)
03392 {
03393   TrackBits *trackbits = (TrackBits *)data;
03394 
03395   if (v->type == VEH_TRAIN && (v->vehstatus & VS_CRASHED) != 0) {
03396     TrackBits train_tbits = Train::From(v)->track;
03397     if (train_tbits == TRACK_BIT_WORMHOLE) {
03398       /* Vehicle is inside a wormhole, v->track contains no useful value then. */
03399       *trackbits |= DiagDirToDiagTrackBits(GetTunnelBridgeDirection(v->tile));
03400     } else if (train_tbits != TRACK_BIT_DEPOT) {
03401       *trackbits |= train_tbits;
03402     }
03403   }
03404 
03405   return NULL;
03406 }
03407 
03415 static void DeleteLastWagon(Train *v)
03416 {
03417   Train *first = v->First();
03418 
03419   /* Go to the last wagon and delete the link pointing there
03420    * *u is then the one-before-last wagon, and *v the last
03421    * one which will physically be removed */
03422   Train *u = v;
03423   for (; v->Next() != NULL; v = v->Next()) u = v;
03424   u->SetNext(NULL);
03425 
03426   if (first != v) {
03427     /* Recalculate cached train properties */
03428     first->ConsistChanged(false);
03429     /* Update the depot window if the first vehicle is in depot -
03430      * if v == first, then it is updated in PreDestructor() */
03431     if (first->track == TRACK_BIT_DEPOT) {
03432       SetWindowDirty(WC_VEHICLE_DEPOT, first->tile);
03433     }
03434   }
03435 
03436   /* 'v' shouldn't be accessed after it has been deleted */
03437   TrackBits trackbits = v->track;
03438   TileIndex tile = v->tile;
03439   Owner owner = v->owner;
03440 
03441   delete v;
03442   v = NULL; // make sure nobody will try to read 'v' anymore
03443 
03444   if (trackbits == TRACK_BIT_WORMHOLE) {
03445     /* Vehicle is inside a wormhole, v->track contains no useful value then. */
03446     trackbits = DiagDirToDiagTrackBits(GetTunnelBridgeDirection(tile));
03447   }
03448 
03449   Track track = TrackBitsToTrack(trackbits);
03450   if (HasReservedTracks(tile, trackbits)) {
03451     UnreserveRailTrack(tile, track);
03452 
03453     /* If there are still crashed vehicles on the tile, give the track reservation to them */
03454     TrackBits remaining_trackbits = TRACK_BIT_NONE;
03455     FindVehicleOnPos(tile, &remaining_trackbits, CollectTrackbitsFromCrashedVehiclesEnum);
03456 
03457     /* It is important that these two are the first in the loop, as reservation cannot deal with every trackbit combination */
03458     assert(TRACK_BEGIN == TRACK_X && TRACK_Y == TRACK_BEGIN + 1);
03459     Track t;
03460     FOR_EACH_SET_TRACK(t, remaining_trackbits) TryReserveRailTrack(tile, t);
03461   }
03462 
03463   /* check if the wagon was on a road/rail-crossing */
03464   if (IsLevelCrossingTile(tile)) UpdateLevelCrossing(tile);
03465 
03466   /* Update signals */
03467   if (IsTileType(tile, MP_TUNNELBRIDGE) || IsRailDepotTile(tile)) {
03468     UpdateSignalsOnSegment(tile, INVALID_DIAGDIR, owner);
03469   } else {
03470     SetSignalsOnBothDir(tile, track, owner);
03471   }
03472 }
03473 
03478 static void ChangeTrainDirRandomly(Train *v)
03479 {
03480   static const DirDiff delta[] = {
03481     DIRDIFF_45LEFT, DIRDIFF_SAME, DIRDIFF_SAME, DIRDIFF_45RIGHT
03482   };
03483 
03484   do {
03485     /* We don't need to twist around vehicles if they're not visible */
03486     if (!(v->vehstatus & VS_HIDDEN)) {
03487       v->direction = ChangeDir(v->direction, delta[GB(Random(), 0, 2)]);
03488       v->UpdateDeltaXY(v->direction);
03489       v->cur_image = v->GetImage(v->direction, EIT_ON_MAP);
03490       /* Refrain from updating the z position of the vehicle when on
03491        * a bridge, because UpdateInclination() will put the vehicle under
03492        * the bridge in that case */
03493       if (v->track != TRACK_BIT_WORMHOLE) {
03494         VehicleUpdatePosition(v);
03495         v->UpdateInclination(false, false);
03496       }
03497     }
03498   } while ((v = v->Next()) != NULL);
03499 }
03500 
03506 static bool HandleCrashedTrain(Train *v)
03507 {
03508   int state = ++v->crash_anim_pos;
03509 
03510   if (state == 4 && !(v->vehstatus & VS_HIDDEN)) {
03511     CreateEffectVehicleRel(v, 4, 4, 8, EV_EXPLOSION_LARGE);
03512   }
03513 
03514   uint32 r;
03515   if (state <= 200 && Chance16R(1, 7, r)) {
03516     int index = (r * 10 >> 16);
03517 
03518     Vehicle *u = v;
03519     do {
03520       if (--index < 0) {
03521         r = Random();
03522 
03523         CreateEffectVehicleRel(u,
03524           GB(r,  8, 3) + 2,
03525           GB(r, 16, 3) + 2,
03526           GB(r,  0, 3) + 5,
03527           EV_EXPLOSION_SMALL);
03528         break;
03529       }
03530     } while ((u = u->Next()) != NULL);
03531   }
03532 
03533   if (state <= 240 && !(v->tick_counter & 3)) ChangeTrainDirRandomly(v);
03534 
03535   if (state >= 4440 && !(v->tick_counter & 0x1F)) {
03536     bool ret = v->Next() != NULL;
03537     DeleteLastWagon(v);
03538     return ret;
03539   }
03540 
03541   return true;
03542 }
03543 
03545 static const uint16 _breakdown_speeds[16] = {
03546   225, 210, 195, 180, 165, 150, 135, 120, 105, 90, 75, 60, 45, 30, 15, 15
03547 };
03548 
03549 
03558 static bool TrainApproachingLineEnd(Train *v, bool signal, bool reverse)
03559 {
03560   /* Calc position within the current tile */
03561   uint x = v->x_pos & 0xF;
03562   uint y = v->y_pos & 0xF;
03563 
03564   /* for diagonal directions, 'x' will be 0..15 -
03565    * for other directions, it will be 1, 3, 5, ..., 15 */
03566   switch (v->direction) {
03567     case DIR_N : x = ~x + ~y + 25; break;
03568     case DIR_NW: x = y;            // FALL THROUGH
03569     case DIR_NE: x = ~x + 16;      break;
03570     case DIR_E : x = ~x + y + 9;   break;
03571     case DIR_SE: x = y;            break;
03572     case DIR_S : x = x + y - 7;    break;
03573     case DIR_W : x = ~y + x + 9;   break;
03574     default: break;
03575   }
03576 
03577   /* Do not reverse when approaching red signal. Make sure the vehicle's front
03578    * does not cross the tile boundary when we do reverse, but as the vehicle's
03579    * location is based on their center, use half a vehicle's length as offset.
03580    * Multiply the half-length by two for straight directions to compensate that
03581    * we only get odd x offsets there. */
03582   if (!signal && x + (v->gcache.cached_veh_length + 1) / 2 * (IsDiagonalDirection(v->direction) ? 1 : 2) >= TILE_SIZE) {
03583     /* we are too near the tile end, reverse now */
03584     v->cur_speed = 0;
03585     if (reverse) ReverseTrainDirection(v);
03586     return false;
03587   }
03588 
03589   /* slow down */
03590   v->vehstatus |= VS_TRAIN_SLOWING;
03591   uint16 break_speed = _breakdown_speeds[x & 0xF];
03592   if (break_speed < v->cur_speed) v->cur_speed = break_speed;
03593 
03594   return true;
03595 }
03596 
03597 
03603 static bool TrainCanLeaveTile(const Train *v)
03604 {
03605   /* Exit if inside a tunnel/bridge or a depot */
03606   if (v->track == TRACK_BIT_WORMHOLE || v->track == TRACK_BIT_DEPOT) return false;
03607 
03608   TileIndex tile = v->tile;
03609 
03610   /* entering a tunnel/bridge? */
03611   if (IsTileType(tile, MP_TUNNELBRIDGE)) {
03612     DiagDirection dir = GetTunnelBridgeDirection(tile);
03613     if (DiagDirToDir(dir) == v->direction) return false;
03614   }
03615 
03616   /* entering a depot? */
03617   if (IsRailDepotTile(tile)) {
03618     DiagDirection dir = ReverseDiagDir(GetRailDepotDirection(tile));
03619     if (DiagDirToDir(dir) == v->direction) return false;
03620   }
03621 
03622   return true;
03623 }
03624 
03625 
03633 static TileIndex TrainApproachingCrossingTile(const Train *v)
03634 {
03635   assert(v->IsFrontEngine());
03636   assert(!(v->vehstatus & VS_CRASHED));
03637 
03638   if (!TrainCanLeaveTile(v)) return INVALID_TILE;
03639 
03640   DiagDirection dir = TrainExitDir(v->direction, v->track);
03641   TileIndex tile = v->tile + TileOffsByDiagDir(dir);
03642 
03643   /* not a crossing || wrong axis || unusable rail (wrong type or owner) */
03644   if (!IsLevelCrossingTile(tile) || DiagDirToAxis(dir) == GetCrossingRoadAxis(tile) ||
03645       !CheckCompatibleRail(v, tile)) {
03646     return INVALID_TILE;
03647   }
03648 
03649   return tile;
03650 }
03651 
03652 
03660 static bool TrainCheckIfLineEnds(Train *v, bool reverse)
03661 {
03662   /* First, handle broken down train */
03663 
03664   int t = v->breakdown_ctr;
03665   if (t > 1) {
03666     v->vehstatus |= VS_TRAIN_SLOWING;
03667 
03668     uint16 break_speed = _breakdown_speeds[GB(~t, 4, 4)];
03669     if (break_speed < v->cur_speed) v->cur_speed = break_speed;
03670   } else {
03671     v->vehstatus &= ~VS_TRAIN_SLOWING;
03672   }
03673 
03674   if (!TrainCanLeaveTile(v)) return true;
03675 
03676   /* Determine the non-diagonal direction in which we will exit this tile */
03677   DiagDirection dir = TrainExitDir(v->direction, v->track);
03678   /* Calculate next tile */
03679   TileIndex tile = v->tile + TileOffsByDiagDir(dir);
03680 
03681   /* Determine the track status on the next tile */
03682   TrackStatus ts = GetTileTrackStatus(tile, TRANSPORT_RAIL, 0, ReverseDiagDir(dir));
03683   TrackdirBits reachable_trackdirs = DiagdirReachesTrackdirs(dir);
03684 
03685   TrackdirBits trackdirbits = TrackStatusToTrackdirBits(ts) & reachable_trackdirs;
03686   TrackdirBits red_signals = TrackStatusToRedSignals(ts) & reachable_trackdirs;
03687 
03688   /* We are sure the train is not entering a depot, it is detected above */
03689 
03690   /* mask unreachable track bits if we are forbidden to do 90deg turns */
03691   TrackBits bits = TrackdirBitsToTrackBits(trackdirbits);
03692   if (_settings_game.pf.forbid_90_deg) {
03693     bits &= ~TrackCrossesTracks(FindFirstTrack(v->track));
03694   }
03695 
03696   /* no suitable trackbits at all || unusable rail (wrong type or owner) */
03697   if (bits == TRACK_BIT_NONE || !CheckCompatibleRail(v, tile)) {
03698     return TrainApproachingLineEnd(v, false, reverse);
03699   }
03700 
03701   /* approaching red signal */
03702   if ((trackdirbits & red_signals) != 0) return TrainApproachingLineEnd(v, true, reverse);
03703 
03704   /* approaching a rail/road crossing? then make it red */
03705   if (IsLevelCrossingTile(tile)) MaybeBarCrossingWithSound(tile);
03706 
03707   return true;
03708 }
03709 
03710 
03711 static bool TrainLocoHandler(Train *v, bool mode)
03712 {
03713   /* train has crashed? */
03714   if (v->vehstatus & VS_CRASHED) {
03715     return mode ? true : HandleCrashedTrain(v); // 'this' can be deleted here
03716   }
03717 
03718   if (v->force_proceed != TFP_NONE) {
03719     ClrBit(v->flags, VRF_TRAIN_STUCK);
03720     SetWindowWidgetDirty(WC_VEHICLE_VIEW, v->index, WID_VV_START_STOP);
03721   }
03722 
03723   /* train is broken down? */
03724   if (v->HandleBreakdown()) return true;
03725 
03726   if (HasBit(v->flags, VRF_REVERSING) && v->cur_speed == 0) {
03727     ReverseTrainDirection(v);
03728   }
03729 
03730   /* exit if train is stopped */
03731   if ((v->vehstatus & VS_STOPPED) && v->cur_speed == 0) return true;
03732 
03733   bool valid_order = !v->current_order.IsType(OT_NOTHING) && v->current_order.GetType() != OT_CONDITIONAL;
03734   if (ProcessOrders(v) && CheckReverseTrain(v)) {
03735     v->wait_counter = 0;
03736     v->cur_speed = 0;
03737     v->subspeed = 0;
03738     ClrBit(v->flags, VRF_LEAVING_STATION);
03739     ReverseTrainDirection(v);
03740     return true;
03741   } else if (HasBit(v->flags, VRF_LEAVING_STATION)) {
03742     /* Try to reserve a path when leaving the station as we
03743      * might not be marked as wanting a reservation, e.g.
03744      * when an overlength train gets turned around in a station. */
03745     DiagDirection dir = TrainExitDir(v->direction, v->track);
03746     if (IsRailDepotTile(v->tile) || IsTileType(v->tile, MP_TUNNELBRIDGE)) dir = INVALID_DIAGDIR;
03747 
03748     if (UpdateSignalsOnSegment(v->tile, dir, v->owner) == SIGSEG_PBS || _settings_game.pf.reserve_paths) {
03749       TryPathReserve(v, true, true);
03750     }
03751     ClrBit(v->flags, VRF_LEAVING_STATION);
03752   }
03753 
03754   v->HandleLoading(mode);
03755 
03756   if (v->current_order.IsType(OT_LOADING)) return true;
03757 
03758   if (CheckTrainStayInDepot(v)) return true;
03759 
03760   if (!mode) v->ShowVisualEffect();
03761 
03762   /* We had no order but have an order now, do look ahead. */
03763   if (!valid_order && !v->current_order.IsType(OT_NOTHING)) {
03764     CheckNextTrainTile(v);
03765   }
03766 
03767   /* Handle stuck trains. */
03768   if (!mode && HasBit(v->flags, VRF_TRAIN_STUCK)) {
03769     ++v->wait_counter;
03770 
03771     /* Should we try reversing this tick if still stuck? */
03772     bool turn_around = v->wait_counter % (_settings_game.pf.wait_for_pbs_path * DAY_TICKS) == 0 && _settings_game.pf.reverse_at_signals;
03773 
03774     if (!turn_around && v->wait_counter % _settings_game.pf.path_backoff_interval != 0 && v->force_proceed == TFP_NONE) return true;
03775     if (!TryPathReserve(v)) {
03776       /* Still stuck. */
03777       if (turn_around) ReverseTrainDirection(v);
03778 
03779       if (HasBit(v->flags, VRF_TRAIN_STUCK) && v->wait_counter > 2 * _settings_game.pf.wait_for_pbs_path * DAY_TICKS) {
03780         /* Show message to player. */
03781         if (_settings_client.gui.lost_vehicle_warn && v->owner == _local_company) {
03782           SetDParam(0, v->index);
03783           AddVehicleAdviceNewsItem(STR_NEWS_TRAIN_IS_STUCK, v->index);
03784         }
03785         v->wait_counter = 0;
03786       }
03787       /* Exit if force proceed not pressed, else reset stuck flag anyway. */
03788       if (v->force_proceed == TFP_NONE) return true;
03789       ClrBit(v->flags, VRF_TRAIN_STUCK);
03790       v->wait_counter = 0;
03791       SetWindowWidgetDirty(WC_VEHICLE_VIEW, v->index, WID_VV_START_STOP);
03792     }
03793   }
03794 
03795   if (v->current_order.IsType(OT_LEAVESTATION)) {
03796     v->current_order.Free();
03797     SetWindowWidgetDirty(WC_VEHICLE_VIEW, v->index, WID_VV_START_STOP);
03798     return true;
03799   }
03800 
03801   int j = v->UpdateSpeed();
03802 
03803   /* we need to invalidate the widget if we are stopping from 'Stopping 0 km/h' to 'Stopped' */
03804   if (v->cur_speed == 0 && (v->vehstatus & VS_STOPPED)) {
03805     /* If we manually stopped, we're not force-proceeding anymore. */
03806     v->force_proceed = TFP_NONE;
03807     SetWindowDirty(WC_VEHICLE_VIEW, v->index);
03808   }
03809 
03810   int adv_spd = v->GetAdvanceDistance();
03811   if (j < adv_spd) {
03812     /* if the vehicle has speed 0, update the last_speed field. */
03813     if (v->cur_speed == 0) v->SetLastSpeed();
03814   } else {
03815     TrainCheckIfLineEnds(v);
03816     /* Loop until the train has finished moving. */
03817     for (;;) {
03818       j -= adv_spd;
03819       TrainController(v, NULL);
03820       /* Don't continue to move if the train crashed. */
03821       if (CheckTrainCollision(v)) break;
03822       /* Determine distance to next map position */
03823       adv_spd = v->GetAdvanceDistance();
03824 
03825       /* No more moving this tick */
03826       if (j < adv_spd || v->cur_speed == 0) break;
03827 
03828       OrderType order_type = v->current_order.GetType();
03829       /* Do not skip waypoints (incl. 'via' stations) when passing through at full speed. */
03830       if ((order_type == OT_GOTO_WAYPOINT || order_type == OT_GOTO_STATION) &&
03831             (v->current_order.GetNonStopType() & ONSF_NO_STOP_AT_DESTINATION_STATION) &&
03832             IsTileType(v->tile, MP_STATION) &&
03833             v->current_order.GetDestination() == GetStationIndex(v->tile)) {
03834         ProcessOrders(v);
03835       }
03836     }
03837     v->SetLastSpeed();
03838   }
03839 
03840   for (Train *u = v; u != NULL; u = u->Next()) {
03841     if ((u->vehstatus & VS_HIDDEN) != 0) continue;
03842 
03843     u->UpdateViewport(false, false);
03844   }
03845 
03846   if (v->progress == 0) v->progress = j; // Save unused spd for next time, if TrainController didn't set progress
03847 
03848   return true;
03849 }
03850 
03855 Money Train::GetRunningCost() const
03856 {
03857   Money cost = 0;
03858   const Train *v = this;
03859 
03860   do {
03861     const Engine *e = v->GetEngine();
03862     if (e->u.rail.running_cost_class == INVALID_PRICE) continue;
03863 
03864     uint cost_factor = GetVehicleProperty(v, PROP_TRAIN_RUNNING_COST_FACTOR, e->u.rail.running_cost);
03865     if (cost_factor == 0) continue;
03866 
03867     /* Halve running cost for multiheaded parts */
03868     if (v->IsMultiheaded()) cost_factor /= 2;
03869 
03870     cost += GetPrice(e->u.rail.running_cost_class, cost_factor, e->GetGRF());
03871   } while ((v = v->GetNextVehicle()) != NULL);
03872 
03873   return cost;
03874 }
03875 
03880 bool Train::Tick()
03881 {
03882   this->tick_counter++;
03883 
03884   if (this->IsFrontEngine()) {
03885     if (!(this->vehstatus & VS_STOPPED) || this->cur_speed > 0) this->running_ticks++;
03886 
03887     this->current_order_time++;
03888 
03889     if (!TrainLocoHandler(this, false)) return false;
03890 
03891     return TrainLocoHandler(this, true);
03892   } else if (this->IsFreeWagon() && (this->vehstatus & VS_CRASHED)) {
03893     /* Delete flooded standalone wagon chain */
03894     if (++this->crash_anim_pos >= 4400) {
03895       delete this;
03896       return false;
03897     }
03898   }
03899 
03900   return true;
03901 }
03902 
03907 static void CheckIfTrainNeedsService(Train *v)
03908 {
03909   if (Company::Get(v->owner)->settings.vehicle.servint_trains == 0 || !v->NeedsAutomaticServicing()) return;
03910   if (v->IsChainInDepot()) {
03911     VehicleServiceInDepot(v);
03912     return;
03913   }
03914 
03915   uint max_penalty;
03916   switch (_settings_game.pf.pathfinder_for_trains) {
03917     case VPF_NPF:  max_penalty = _settings_game.pf.npf.maximum_go_to_depot_penalty;  break;
03918     case VPF_YAPF: max_penalty = _settings_game.pf.yapf.maximum_go_to_depot_penalty; break;
03919     default: NOT_REACHED();
03920   }
03921 
03922   FindDepotData tfdd = FindClosestTrainDepot(v, max_penalty);
03923   /* Only go to the depot if it is not too far out of our way. */
03924   if (tfdd.best_length == UINT_MAX || tfdd.best_length > max_penalty) {
03925     if (v->current_order.IsType(OT_GOTO_DEPOT)) {
03926       /* If we were already heading for a depot but it has
03927        * suddenly moved farther away, we continue our normal
03928        * schedule? */
03929       v->current_order.MakeDummy();
03930       SetWindowWidgetDirty(WC_VEHICLE_VIEW, v->index, WID_VV_START_STOP);
03931     }
03932     return;
03933   }
03934 
03935   DepotID depot = GetDepotIndex(tfdd.tile);
03936 
03937   if (v->current_order.IsType(OT_GOTO_DEPOT) &&
03938       v->current_order.GetDestination() != depot &&
03939       !Chance16(3, 16)) {
03940     return;
03941   }
03942 
03943   SetBit(v->gv_flags, GVF_SUPPRESS_IMPLICIT_ORDERS);
03944   v->current_order.MakeGoToDepot(depot, ODTFB_SERVICE);
03945   v->dest_tile = tfdd.tile;
03946   SetWindowWidgetDirty(WC_VEHICLE_VIEW, v->index, WID_VV_START_STOP);
03947 }
03948 
03950 void Train::OnNewDay()
03951 {
03952   AgeVehicle(this);
03953 
03954   if ((++this->day_counter & 7) == 0) DecreaseVehicleValue(this);
03955 
03956   if (this->IsFrontEngine()) {
03957     CheckVehicleBreakdown(this);
03958 
03959     CheckIfTrainNeedsService(this);
03960 
03961     CheckOrders(this);
03962 
03963     /* update destination */
03964     if (this->current_order.IsType(OT_GOTO_STATION)) {
03965       TileIndex tile = Station::Get(this->current_order.GetDestination())->train_station.tile;
03966       if (tile != INVALID_TILE) this->dest_tile = tile;
03967     }
03968 
03969     if (this->running_ticks != 0) {
03970       /* running costs */
03971       CommandCost cost(EXPENSES_TRAIN_RUN, this->GetRunningCost() * this->running_ticks / (DAYS_IN_YEAR  * DAY_TICKS));
03972 
03973       this->profit_this_year -= cost.GetCost();
03974       this->running_ticks = 0;
03975 
03976       SubtractMoneyFromCompanyFract(this->owner, cost);
03977 
03978       SetWindowDirty(WC_VEHICLE_DETAILS, this->index);
03979       SetWindowClassesDirty(WC_TRAINS_LIST);
03980     }
03981   }
03982 }
03983 
03988 Trackdir Train::GetVehicleTrackdir() const
03989 {
03990   if (this->vehstatus & VS_CRASHED) return INVALID_TRACKDIR;
03991 
03992   if (this->track == TRACK_BIT_DEPOT) {
03993     /* We'll assume the train is facing outwards */
03994     return DiagDirToDiagTrackdir(GetRailDepotDirection(this->tile)); // Train in depot
03995   }
03996 
03997   if (this->track == TRACK_BIT_WORMHOLE) {
03998     /* train in tunnel or on bridge, so just use his direction and assume a diagonal track */
03999     return DiagDirToDiagTrackdir(DirToDiagDir(this->direction));
04000   }
04001 
04002   return TrackDirectionToTrackdir(FindFirstTrack(this->track), this->direction);
04003 }