# npf.cpp

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    00001 /* $Id$ */
    00002
    00003 /*
    00004  * This file is part of OpenTTD.
    00005  * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
    00006  * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
    00007  * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
    00008  */
    00009
    00012 #include "../../stdafx.h"
    00013 #include "../../debug.h"
    00014 #include "../../network/network.h"
    00015 #include "../../viewport_func.h"
    00016 #include "../../ship.h"
    00017 #include "../../roadstop_base.h"
    00018 #include "../pathfinder_func.h"
    00019 #include "../pathfinder_type.h"
    00020 #include "../follow_track.hpp"
    00021 #include "aystar.h"
    00022
    00023 static const uint NPF_HASH_BITS = 12;
    00024 /* Do no change below values */
    00025 static const uint NPF_HASH_SIZE = 1 << NPF_HASH_BITS;
    00026 static const uint NPF_HASH_HALFBITS = NPF_HASH_BITS / 2;
    00027 static const uint NPF_HASH_HALFMASK = (1 << NPF_HASH_HALFBITS) - 1;
    00028
    00030 struct NPFFindStationOrTileData {
    00031   TileIndex dest_coords;
    00032   StationID station_index;
    00033   bool reserve_path;
    00034   StationType station_type;
    00035   bool not_articulated;
    00036   const Vehicle *v;
    00037 };
    00038
    00040 enum AyStarUserDataType {
    00041   NPF_TYPE = 0,
    00042   NPF_SUB_TYPE,
    00043   NPF_OWNER,
    00044   NPF_RAILTYPES,
    00045 };
    00046
    00048 enum AyStarNodeUserDataType {
    00049   NPF_TRACKDIR_CHOICE = 0,
    00050   NPF_NODE_FLAGS,
    00051 };
    00052
    00054 enum NPFNodeFlag {
    00055   NPF_FLAG_SEEN_SIGNAL,
    00056   NPF_FLAG_2ND_SIGNAL,
    00057   NPF_FLAG_3RD_SIGNAL,
    00058   NPF_FLAG_REVERSE,
    00059   NPF_FLAG_LAST_SIGNAL_RED,
    00060   NPF_FLAG_LAST_SIGNAL_BLOCK,
    00061   NPF_FLAG_IGNORE_START_TILE,
    00062   NPF_FLAG_TARGET_RESERVED,
    00063   NPF_FLAG_IGNORE_RESERVED,
    00064 };
    00065
    00067 struct NPFFoundTargetData {
    00068   uint best_bird_dist;
    00069   uint best_path_dist;
    00070   Trackdir best_trackdir;
    00071   AyStarNode node;
    00072   bool res_okay;
    00073 };
    00074
    00075 static AyStar _npf_aystar;
    00076
    00077 /* The cost of each trackdir. A diagonal piece is the full NPF_TILE_LENGTH,
    00078  * the shorter piece is sqrt(2)/2*NPF_TILE_LENGTH =~ 0.7071
    00079  */
    00080 #define NPF_STRAIGHT_LENGTH (uint)(NPF_TILE_LENGTH * STRAIGHT_TRACK_LENGTH)
    00081 static const uint _trackdir_length[TRACKDIR_END] = {
    00082   NPF_TILE_LENGTH, NPF_TILE_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH,
    00083   0, 0,
    00084   NPF_TILE_LENGTH, NPF_TILE_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH
    00085 };
    00086
    00090 static inline bool NPFGetFlag(const AyStarNode *node, NPFNodeFlag flag)
    00091 {
    00092   return HasBit(node->user_data[NPF_NODE_FLAGS], flag);
    00093 }
    00094
    00098 static inline void NPFSetFlag(AyStarNode *node, NPFNodeFlag flag, bool value)
    00099 {
    00100   SB(node->user_data[NPF_NODE_FLAGS], flag, 1, value);
    00101 }
    00102
    00109 static uint NPFDistanceTrack(TileIndex t0, TileIndex t1)
    00110 {
    00111   const uint dx = Delta(TileX(t0), TileX(t1));
    00112   const uint dy = Delta(TileY(t0), TileY(t1));
    00113
    00114   const uint straightTracks = 2 * min(dx, dy); // The number of straight (not full length) tracks
    00115   /* OPTIMISATION:
    00116    * Original: diagTracks = max(dx, dy) - min(dx,dy);
    00117    * Proof:
    00118    * (dx+dy) - straightTracks  == (min + max) - straightTracks = min + max - 2 * min = max - min */
    00119   const uint diagTracks = dx + dy - straightTracks; // The number of diagonal (full tile length) tracks.
    00120
    00121   /* Don't factor out NPF_TILE_LENGTH below, this will round values and lose
    00122    * precision */
    00123   return diagTracks * NPF_TILE_LENGTH + straightTracks * NPF_TILE_LENGTH * STRAIGHT_TRACK_LENGTH;
    00124 }
    00125
    00133 static uint NPFHash(uint key1, uint key2)
    00134 {
    00135   /* TODO: think of a better hash? */
    00136   uint part1 = TileX(key1) & NPF_HASH_HALFMASK;
    00137   uint part2 = TileY(key1) & NPF_HASH_HALFMASK;
    00138
    00139   assert(IsValidTrackdir((Trackdir)key2));
    00140   assert(IsValidTile(key1));
    00141   return ((part1 << NPF_HASH_HALFBITS | part2) + (NPF_HASH_SIZE * key2 / TRACKDIR_END)) % NPF_HASH_SIZE;
    00142 }
    00143
    00144 static int32 NPFCalcZero(AyStar *as, AyStarNode *current, OpenListNode *parent)
    00145 {
    00146   return 0;
    00147 }
    00148
    00149 /* Calcs the heuristic to the target station or tile. For train stations, it
    00150  * takes into account the direction of approach.
    00151  */
    00152 static int32 NPFCalcStationOrTileHeuristic(AyStar *as, AyStarNode *current, OpenListNode *parent)
    00153 {
    00154   NPFFindStationOrTileData *fstd = (NPFFindStationOrTileData*)as->user_target;
    00155   NPFFoundTargetData *ftd = (NPFFoundTargetData*)as->user_path;
    00156   TileIndex from = current->tile;
    00157   TileIndex to = fstd->dest_coords;
    00158   uint dist;
    00159
    00160   /* for train-stations, we are going to aim for the closest station tile */
    00161   if (as->user_data[NPF_TYPE] != TRANSPORT_WATER && fstd->station_index != INVALID_STATION) {
    00162     to = CalcClosestStationTile(fstd->station_index, from, fstd->station_type);
    00163   }
    00164
    00165   if (as->user_data[NPF_TYPE] == TRANSPORT_ROAD) {
    00166     /* Since roads only have diagonal pieces, we use manhattan distance here */
    00167     dist = DistanceManhattan(from, to) * NPF_TILE_LENGTH;
    00168   } else {
    00169     /* Ships and trains can also go diagonal, so the minimum distance is shorter */
    00170     dist = NPFDistanceTrack(from, to);
    00171   }
    00172
    00173   DEBUG(npf, 4, "Calculating H for: (%d, %d). Result: %d", TileX(current->tile), TileY(current->tile), dist);
    00174
    00175   if (dist < ftd->best_bird_dist) {
    00176     ftd->best_bird_dist = dist;
    00177     ftd->best_trackdir = (Trackdir)current->user_data[NPF_TRACKDIR_CHOICE];
    00178   }
    00179   return dist;
    00180 }
    00181
    00182
    00183 /* Fills AyStarNode.user_data[NPF_TRACKDIRCHOICE] with the chosen direction to
    00184  * get here, either getting it from the current choice or from the parent's
    00185  * choice */
    00186 static void NPFFillTrackdirChoice(AyStarNode *current, OpenListNode *parent)
    00187 {
    00188   if (parent->path.parent == NULL) {
    00189     Trackdir trackdir = current->direction;
    00190     /* This is a first order decision, so we'd better save the
    00191      * direction we chose */
    00192     current->user_data[NPF_TRACKDIR_CHOICE] = trackdir;
    00193     DEBUG(npf, 6, "Saving trackdir: 0x%X", trackdir);
    00194   } else {
    00195     /* We've already made the decision, so just save our parent's decision */
    00196     current->user_data[NPF_TRACKDIR_CHOICE] = parent->path.node.user_data[NPF_TRACKDIR_CHOICE];
    00197   }
    00198 }
    00199
    00200 /* Will return the cost of the tunnel. If it is an entry, it will return the
    00201  * cost of that tile. If the tile is an exit, it will return the tunnel length
    00202  * including the exit tile. Requires that this is a Tunnel tile */
    00203 static uint NPFTunnelCost(AyStarNode *current)
    00204 {
    00205   DiagDirection exitdir = TrackdirToExitdir(current->direction);
    00206   TileIndex tile = current->tile;
    00207   if (GetTunnelBridgeDirection(tile) == ReverseDiagDir(exitdir)) {
    00208     /* We just popped out if this tunnel, since were
    00209      * facing the tunnel exit */
    00210     return NPF_TILE_LENGTH * (GetTunnelBridgeLength(current->tile, GetOtherTunnelEnd(current->tile)) + 1);
    00211     /* @todo: Penalty for tunnels? */
    00212   } else {
    00213     /* We are entering the tunnel, the enter tile is just a
    00214      * straight track */
    00215     return NPF_TILE_LENGTH;
    00216   }
    00217 }
    00218
    00219 static inline uint NPFBridgeCost(AyStarNode *current)
    00220 {
    00221   return NPF_TILE_LENGTH * GetTunnelBridgeLength(current->tile, GetOtherBridgeEnd(current->tile));
    00222 }
    00223
    00224 static uint NPFSlopeCost(AyStarNode *current)
    00225 {
    00226   TileIndex next = current->tile + TileOffsByDiagDir(TrackdirToExitdir(current->direction));
    00227
    00228   /* Get center of tiles */
    00229   int x1 = TileX(current->tile) * TILE_SIZE + TILE_SIZE / 2;
    00230   int y1 = TileY(current->tile) * TILE_SIZE + TILE_SIZE / 2;
    00231   int x2 = TileX(next) * TILE_SIZE + TILE_SIZE / 2;
    00232   int y2 = TileY(next) * TILE_SIZE + TILE_SIZE / 2;
    00233
    00234   int dx4 = (x2 - x1) / 4;
    00235   int dy4 = (y2 - y1) / 4;
    00236
    00237   /* Get the height on both sides of the tile edge.
    00238    * Avoid testing the height on the tile-center. This will fail for halftile-foundations.
    00239    */
    00240   int z1 = GetSlopeZ(x1 + dx4, y1 + dy4);
    00241   int z2 = GetSlopeZ(x2 - dx4, y2 - dy4);
    00242
    00243   if (z2 - z1 > 1) {
    00244     /* Slope up */
    00245     return _settings_game.pf.npf.npf_rail_slope_penalty;
    00246   }
    00247   return 0;
    00248   /* Should we give a bonus for slope down? Probably not, we
    00249    * could just substract that bonus from the penalty, because
    00250    * there is only one level of steepness... */
    00251 }
    00252
    00253 static uint NPFReservedTrackCost(AyStarNode *current)
    00254 {
    00255   TileIndex tile = current->tile;
    00256   TrackBits track = TrackToTrackBits(TrackdirToTrack(current->direction));
    00257   TrackBits res = GetReservedTrackbits(tile);
    00258
    00259   if (NPFGetFlag(current, NPF_FLAG_3RD_SIGNAL) || NPFGetFlag(current, NPF_FLAG_LAST_SIGNAL_BLOCK) || ((res & track) == TRACK_BIT_NONE && !TracksOverlap(res | track))) return 0;
    00260
    00261   if (IsTileType(tile, MP_TUNNELBRIDGE)) {
    00262     DiagDirection exitdir = TrackdirToExitdir(current->direction);
    00263     if (GetTunnelBridgeDirection(tile) == ReverseDiagDir(exitdir)) {
    00264       return  _settings_game.pf.npf.npf_rail_pbs_cross_penalty * (GetTunnelBridgeLength(tile, GetOtherTunnelBridgeEnd(tile)) + 1);
    00265     }
    00266   }
    00267   return  _settings_game.pf.npf.npf_rail_pbs_cross_penalty;
    00268 }
    00269
    00274 static void NPFMarkTile(TileIndex tile)
    00275 {
    00276 #ifndef NO_DEBUG_MESSAGES
    00277   if (_debug_npf_level < 1 || _networking) return;
    00278   switch (GetTileType(tile)) {
    00279     case MP_RAILWAY:
    00280       /* DEBUG: mark visited tiles by mowing the grass under them ;-) */
    00281       if (!IsRailDepot(tile)) {
    00282         SetRailGroundType(tile, RAIL_GROUND_BARREN);
    00283         MarkTileDirtyByTile(tile);
    00284       }
    00285       break;
    00286
    00287     case MP_ROAD:
    00288       if (!IsRoadDepot(tile)) {
    00289         SetRoadside(tile, ROADSIDE_BARREN);
    00290         MarkTileDirtyByTile(tile);
    00291       }
    00292       break;
    00293
    00294     default:
    00295       break;
    00296   }
    00297 #endif
    00298 }
    00299
    00300 static int32 NPFWaterPathCost(AyStar *as, AyStarNode *current, OpenListNode *parent)
    00301 {
    00302   /* TileIndex tile = current->tile; */
    00303   int32 cost = 0;
    00304   Trackdir trackdir = current->direction;
    00305
    00306   cost = _trackdir_length[trackdir]; // Should be different for diagonal tracks
    00307
    00308   if (IsBuoyTile(current->tile) && IsDiagonalTrackdir(trackdir)) {
    00309     cost += _settings_game.pf.npf.npf_buoy_penalty; // A small penalty for going over buoys
    00310   }
    00311
    00312   if (current->direction != NextTrackdir((Trackdir)parent->path.node.direction)) {
    00313     cost += _settings_game.pf.npf.npf_water_curve_penalty;
    00314   }
    00315
    00316   /* @todo More penalties? */
    00317
    00318   return cost;
    00319 }
    00320
    00321 /* Determine the cost of this node, for road tracks */
    00322 static int32 NPFRoadPathCost(AyStar *as, AyStarNode *current, OpenListNode *parent)
    00323 {
    00324   TileIndex tile = current->tile;
    00325   int32 cost = 0;
    00326
    00327   /* Determine base length */
    00328   switch (GetTileType(tile)) {
    00329     case MP_TUNNELBRIDGE:
    00330       cost = IsTunnel(tile) ? NPFTunnelCost(current) : NPFBridgeCost(current);
    00331       break;
    00332
    00333     case MP_ROAD:
    00334       cost = NPF_TILE_LENGTH;
    00335       /* Increase the cost for level crossings */
    00336       if (IsLevelCrossing(tile)) cost += _settings_game.pf.npf.npf_crossing_penalty;
    00337       break;
    00338
    00339     case MP_STATION: {
    00340       cost = NPF_TILE_LENGTH;
    00341       const RoadStop *rs = RoadStop::GetByTile(tile, GetRoadStopType(tile));
    00342       if (IsDriveThroughStopTile(tile)) {
    00343         /* Increase the cost for drive-through road stops */
    00344         cost += _settings_game.pf.npf.npf_road_drive_through_penalty;
    00345         DiagDirection dir = TrackdirToExitdir(current->direction);
    00346         if (!RoadStop::IsDriveThroughRoadStopContinuation(tile, tile - TileOffsByDiagDir(dir))) {
    00347           /* When we're the first road stop in a 'queue' of them we increase
    00348            * cost based on the fill percentage of the whole queue. */
    00349           const RoadStop::Entry *entry = rs->GetEntry(dir);
    00350           cost += entry->GetOccupied() * _settings_game.pf.npf.npf_road_dt_occupied_penalty / entry->GetLength();
    00351         }
    00352       } else {
    00353         /* Increase cost for filled road stops */
    00354         cost += _settings_game.pf.npf.npf_road_bay_occupied_penalty * (!rs->IsFreeBay(0) + !rs->IsFreeBay(1)) / 2;
    00355       }
    00356       break;
    00357     }
    00358
    00359     default:
    00360       break;
    00361   }
    00362
    00363   /* Determine extra costs */
    00364
    00365   /* Check for slope */
    00366   cost += NPFSlopeCost(current);
    00367
    00368   /* Check for turns. Road vehicles only really drive diagonal, turns are
    00369    * represented by non-diagonal tracks */
    00370   if (!IsDiagonalTrackdir(current->direction)) {
    00371     cost += _settings_game.pf.npf.npf_road_curve_penalty;
    00372   }
    00373
    00374   NPFMarkTile(tile);
    00375   DEBUG(npf, 4, "Calculating G for: (%d, %d). Result: %d", TileX(current->tile), TileY(current->tile), cost);
    00376   return cost;
    00377 }
    00378
    00379
    00380 /* Determine the cost of this node, for railway tracks */
    00381 static int32 NPFRailPathCost(AyStar *as, AyStarNode *current, OpenListNode *parent)
    00382 {
    00383   TileIndex tile = current->tile;
    00384   Trackdir trackdir = current->direction;
    00385   int32 cost = 0;
    00386   /* HACK: We create a OpenListNode manually, so we can call EndNodeCheck */
    00387   OpenListNode new_node;
    00388
    00389   /* Determine base length */
    00390   switch (GetTileType(tile)) {
    00391     case MP_TUNNELBRIDGE:
    00392       cost = IsTunnel(tile) ? NPFTunnelCost(current) : NPFBridgeCost(current);
    00393       break;
    00394
    00395     case MP_RAILWAY:
    00396       cost = _trackdir_length[trackdir]; // Should be different for diagonal tracks
    00397       break;
    00398
    00399     case MP_ROAD: // Railway crossing
    00400       cost = NPF_TILE_LENGTH;
    00401       break;
    00402
    00403     case MP_STATION:
    00404       /* We give a station tile a penalty. Logically we would only want to give
    00405        * station tiles that are not our destination this penalty. This would
    00406        * discourage trains to drive through busy stations. But, we can just
    00407        * give any station tile a penalty, because every possible route will get
    00408        * this penalty exactly once, on its end tile (if it's a station) and it
    00409        * will therefore not make a difference. */
    00410       cost = NPF_TILE_LENGTH + _settings_game.pf.npf.npf_rail_station_penalty;
    00411
    00412       if (IsRailWaypoint(tile)) {
    00413         NPFFindStationOrTileData *fstd = (NPFFindStationOrTileData*)as->user_target;
    00414         if (fstd->v->current_order.IsType(OT_GOTO_WAYPOINT) && GetStationIndex(tile) == fstd->v->current_order.GetDestination()) {
    00415           /* This waypoint is our destination; maybe this isn't an unreserved
    00416            * one, so check that and if so see that as the last signal being
    00417            * red. This way waypoints near stations should work better. */
    00418           const Train *train = Train::From(fstd->v);
    00419           CFollowTrackRail ft(train);
    00420           TileIndex t = tile;
    00421           Trackdir td = trackdir;
    00422           while (ft.Follow(t, td)) {
    00423             assert(t != ft.m_new_tile);
    00424             t = ft.m_new_tile;
    00425             if (KillFirstBit(ft.m_new_td_bits) != TRACKDIR_BIT_NONE) {
    00426               /* We encountered a junction; it's going to be too complex to
    00427                * handle this perfectly, so just bail out. There is no simple
    00428                * free path, so try the other possibilities. */
    00429               td = INVALID_TRACKDIR;
    00430               break;
    00431             }
    00432             td = RemoveFirstTrackdir(&ft.m_new_td_bits);
    00433             /* If this is a safe waiting position we're done searching for it */
    00434             if (IsSafeWaitingPosition(train, t, td, true, _settings_game.pf.forbid_90_deg)) break;
    00435           }
    00436           if (td == INVALID_TRACKDIR ||
    00437               !IsSafeWaitingPosition(train, t, td, true, _settings_game.pf.forbid_90_deg) ||
    00438               !IsWaitingPositionFree(train, t, td, _settings_game.pf.forbid_90_deg)) {
    00439             cost += _settings_game.pf.npf.npf_rail_lastred_penalty;
    00440           }
    00441         }
    00442       }
    00443       break;
    00444
    00445     default:
    00446       break;
    00447   }
    00448
    00449   /* Determine extra costs */
    00450
    00451   /* Check for signals */
    00452   if (IsTileType(tile, MP_RAILWAY)) {
    00453     if (HasSignalOnTrackdir(tile, trackdir)) {
    00454       SignalType sigtype = GetSignalType(tile, TrackdirToTrack(trackdir));
    00455       /* Ordinary track with signals */
    00456       if (GetSignalStateByTrackdir(tile, trackdir) == SIGNAL_STATE_RED) {
    00457         /* Signal facing us is red */
    00458         if (!NPFGetFlag(current, NPF_FLAG_SEEN_SIGNAL)) {
    00459           /* Penalize the first signal we
    00460            * encounter, if it is red */
    00461
    00462           /* Is this a presignal exit or combo? */
    00463           if (!IsPbsSignal(sigtype)) {
    00464             if (sigtype == SIGTYPE_EXIT || sigtype == SIGTYPE_COMBO) {
    00465               /* Penalise exit and combo signals differently (heavier) */
    00466               cost += _settings_game.pf.npf.npf_rail_firstred_exit_penalty;
    00467             } else {
    00468               cost += _settings_game.pf.npf.npf_rail_firstred_penalty;
    00469             }
    00470           }
    00471         }
    00472         /* Record the state of this signal. Path signals are assumed to
    00473          * be green as the signal state of them has no meaning for this. */
    00474         NPFSetFlag(current, NPF_FLAG_LAST_SIGNAL_RED, !IsPbsSignal(sigtype));
    00475       } else {
    00476         /* Record the state of this signal */
    00477         NPFSetFlag(current, NPF_FLAG_LAST_SIGNAL_RED, false);
    00478       }
    00479       if (NPFGetFlag(current, NPF_FLAG_SEEN_SIGNAL)) {
    00480         if (NPFGetFlag(current, NPF_FLAG_2ND_SIGNAL)) {
    00481           NPFSetFlag(current, NPF_FLAG_3RD_SIGNAL, true);
    00482         } else {
    00483           NPFSetFlag(current, NPF_FLAG_2ND_SIGNAL, true);
    00484         }
    00485       } else {
    00486         NPFSetFlag(current, NPF_FLAG_SEEN_SIGNAL, true);
    00487       }
    00488       NPFSetFlag(current, NPF_FLAG_LAST_SIGNAL_BLOCK, !IsPbsSignal(sigtype));
    00489     }
    00490
    00491     if (HasPbsSignalOnTrackdir(tile, ReverseTrackdir(trackdir)) && !NPFGetFlag(current, NPF_FLAG_3RD_SIGNAL)) {
    00492       cost += _settings_game.pf.npf.npf_rail_pbs_signal_back_penalty;
    00493     }
    00494   }
    00495
    00496   /* Penalise the tile if it is a target tile and the last signal was
    00497    * red */
    00498   /* HACK: We create a new_node here so we can call EndNodeCheck. Ugly as hell
    00499    * of course... */
    00500   new_node.path.node = *current;
    00501   if (as->EndNodeCheck(as, &new_node) == AYSTAR_FOUND_END_NODE && NPFGetFlag(current, NPF_FLAG_LAST_SIGNAL_RED)) {
    00502     cost += _settings_game.pf.npf.npf_rail_lastred_penalty;
    00503   }
    00504
    00505   /* Check for slope */
    00506   cost += NPFSlopeCost(current);
    00507
    00508   /* Check for turns */
    00509   if (current->direction != NextTrackdir((Trackdir)parent->path.node.direction)) {
    00510     cost += _settings_game.pf.npf.npf_rail_curve_penalty;
    00511   }
    00512   /* TODO, with realistic acceleration, also the amount of straight track between
    00513    *      curves should be taken into account, as this affects the speed limit. */
    00514
    00515   /* Check for reverse in depot */
    00516   if (IsRailDepotTile(tile) && as->EndNodeCheck(as, &new_node) != AYSTAR_FOUND_END_NODE) {
    00517     /* Penalise any depot tile that is not the last tile in the path. This
    00518      * _should_ penalise every occurrence of reversing in a depot (and only
    00519      * that) */
    00520     cost += _settings_game.pf.npf.npf_rail_depot_reverse_penalty;
    00521   }
    00522
    00523   /* Check for occupied track */
    00524   cost += NPFReservedTrackCost(current);
    00525
    00526   NPFMarkTile(tile);
    00527   DEBUG(npf, 4, "Calculating G for: (%d, %d). Result: %d", TileX(current->tile), TileY(current->tile), cost);
    00528   return cost;
    00529 }
    00530
    00531 /* Will find any depot */
    00532 static int32 NPFFindDepot(AyStar *as, OpenListNode *current)
    00533 {
    00534   /* It's not worth caching the result with NPF_FLAG_IS_TARGET here as below,
    00535    * since checking the cache not that much faster than the actual check */
    00536   return IsDepotTypeTile(current->path.node.tile, (TransportType)as->user_data[NPF_TYPE]) ?
    00537     AYSTAR_FOUND_END_NODE : AYSTAR_DONE;
    00538 }
    00539
    00541 static int32 NPFFindSafeTile(AyStar *as, OpenListNode *current)
    00542 {
    00543   const Train *v = Train::From(((NPFFindStationOrTileData *)as->user_target)->v);
    00544
    00545   return (IsSafeWaitingPosition(v, current->path.node.tile, current->path.node.direction, true, _settings_game.pf.forbid_90_deg) &&
    00546       IsWaitingPositionFree(v, current->path.node.tile, current->path.node.direction, _settings_game.pf.forbid_90_deg)) ?
    00547         AYSTAR_FOUND_END_NODE : AYSTAR_DONE;
    00548 }
    00549
    00550 /* Will find a station identified using the NPFFindStationOrTileData */
    00551 static int32 NPFFindStationOrTile(AyStar *as, OpenListNode *current)
    00552 {
    00553   NPFFindStationOrTileData *fstd = (NPFFindStationOrTileData*)as->user_target;
    00554   AyStarNode *node = &current->path.node;
    00555   TileIndex tile = node->tile;
    00556
    00557   if (fstd->station_index == INVALID_STATION && tile == fstd->dest_coords) return AYSTAR_FOUND_END_NODE;
    00558
    00559   if (IsTileType(tile, MP_STATION) && GetStationIndex(tile) == fstd->station_index) {
    00560     if (fstd->v->type == VEH_TRAIN) return AYSTAR_FOUND_END_NODE;
    00561
    00562     assert(fstd->v->type == VEH_ROAD);
    00563     /* Only if it is a valid station *and* we can stop there */
    00564     if (GetStationType(tile) == fstd->station_type && (fstd->not_articulated || IsDriveThroughStopTile(tile))) return AYSTAR_FOUND_END_NODE;
    00565   }
    00566   return AYSTAR_DONE;
    00567 }
    00568
    00576 static const PathNode *FindSafePosition(PathNode *path, const Train *v)
    00577 {
    00578   /* If there is no signal, reserve the whole path. */
    00579   PathNode *sig = path;
    00580
    00581   for (; path->parent != NULL; path = path->parent) {
    00582     if (IsSafeWaitingPosition(v, path->node.tile, path->node.direction, true, _settings_game.pf.forbid_90_deg)) {
    00583       sig = path;
    00584     }
    00585   }
    00586
    00587   return sig;
    00588 }
    00589
    00593 static void ClearPathReservation(const PathNode *start, const PathNode *end)
    00594 {
    00595   bool first_run = true;
    00596   for (; start != end; start = start->parent) {
    00597     if (IsRailStationTile(start->node.tile) && first_run) {
    00598       SetRailStationPlatformReservation(start->node.tile, TrackdirToExitdir(start->node.direction), false);
    00599     } else {
    00600       UnreserveRailTrack(start->node.tile, TrackdirToTrack(start->node.direction));
    00601     }
    00602     first_run = false;
    00603   }
    00604 }
    00605
    00612 static void NPFSaveTargetData(AyStar *as, OpenListNode *current)
    00613 {
    00614   NPFFoundTargetData *ftd = (NPFFoundTargetData*)as->user_path;
    00615   ftd->best_trackdir = (Trackdir)current->path.node.user_data[NPF_TRACKDIR_CHOICE];
    00616   ftd->best_path_dist = current->g;
    00617   ftd->best_bird_dist = 0;
    00618   ftd->node = current->path.node;
    00619   ftd->res_okay = false;
    00620
    00621   if (as->user_target != NULL && ((NPFFindStationOrTileData*)as->user_target)->reserve_path && as->user_data[NPF_TYPE] == TRANSPORT_RAIL) {
    00622     /* Path reservation is requested. */
    00623     const Train *v = Train::From(((NPFFindStationOrTileData *)as->user_target)->v);
    00624
    00625     const PathNode *target = FindSafePosition(&current->path, v);
    00626     ftd->node = target->node;
    00627
    00628     /* If the target is a station skip to platform end. */
    00629     if (IsRailStationTile(target->node.tile)) {
    00630       DiagDirection dir = TrackdirToExitdir(target->node.direction);
    00631       uint len = Station::GetByTile(target->node.tile)->GetPlatformLength(target->node.tile, dir);
    00632       TileIndex end_tile = TILE_ADD(target->node.tile, (len - 1) * TileOffsByDiagDir(dir));
    00633
    00634       /* Update only end tile, trackdir of a station stays the same. */
    00635       ftd->node.tile = end_tile;
    00636       if (!IsWaitingPositionFree(v, end_tile, target->node.direction, _settings_game.pf.forbid_90_deg)) return;
    00637       SetRailStationPlatformReservation(target->node.tile, dir, true);
    00638       SetRailStationReservation(target->node.tile, false);
    00639     } else {
    00640       if (!IsWaitingPositionFree(v, target->node.tile, target->node.direction, _settings_game.pf.forbid_90_deg)) return;
    00641     }
    00642
    00643     for (const PathNode *cur = target; cur->parent != NULL; cur = cur->parent) {
    00644       if (!TryReserveRailTrack(cur->node.tile, TrackdirToTrack(cur->node.direction))) {
    00645         /* Reservation failed, undo. */
    00646         ClearPathReservation(target, cur);
    00647         return;
    00648       }
    00649     }
    00650
    00651     ftd->res_okay = true;
    00652   }
    00653 }
    00654
    00664 static bool CanEnterTileOwnerCheck(Owner owner, TileIndex tile, DiagDirection enterdir)
    00665 {
    00666   if (IsTileType(tile, MP_RAILWAY) || // Rail tile (also rail depot)
    00667       HasStationTileRail(tile) ||     // Rail station tile/waypoint
    00668       IsRoadDepotTile(tile) ||        // Road depot tile
    00669       IsStandardRoadStopTile(tile)) { // Road station tile (but not drive-through stops)
    00670     return IsTileOwner(tile, owner);  // You need to own these tiles entirely to use them
    00671   }
    00672
    00673   switch (GetTileType(tile)) {
    00674     case MP_ROAD:
    00675       /* rail-road crossing : are we looking at the railway part? */
    00676       if (IsLevelCrossing(tile) &&
    00677           DiagDirToAxis(enterdir) != GetCrossingRoadAxis(tile)) {
    00678         return IsTileOwner(tile, owner); // Railway needs owner check, while the street is public
    00679       }
    00680       break;
    00681
    00682     case MP_TUNNELBRIDGE:
    00683       if (GetTunnelBridgeTransportType(tile) == TRANSPORT_RAIL) {
    00684         return IsTileOwner(tile, owner);
    00685       }
    00686       break;
    00687
    00688     default:
    00689       break;
    00690   }
    00691
    00692   return true; // no need to check
    00693 }
    00694
    00695
    00699 static DiagDirection GetDepotDirection(TileIndex tile, TransportType type)
    00700 {
    00701   assert(IsDepotTypeTile(tile, type));
    00702
    00703   switch (type) {
    00704     case TRANSPORT_RAIL:  return GetRailDepotDirection(tile);
    00705     case TRANSPORT_ROAD:  return GetRoadDepotDirection(tile);
    00706     case TRANSPORT_WATER: return GetShipDepotDirection(tile);
    00707     default: return INVALID_DIAGDIR; // Not reached
    00708   }
    00709 }
    00710
    00712 static DiagDirection GetSingleTramBit(TileIndex tile)
    00713 {
    00714   if (IsNormalRoadTile(tile)) {
    00715     RoadBits rb = GetRoadBits(tile, ROADTYPE_TRAM);
    00716     switch (rb) {
    00717       case ROAD_NW: return DIAGDIR_NW;
    00718       case ROAD_SW: return DIAGDIR_SW;
    00719       case ROAD_SE: return DIAGDIR_SE;
    00720       case ROAD_NE: return DIAGDIR_NE;
    00721       default: break;
    00722     }
    00723   }
    00724   return INVALID_DIAGDIR;
    00725 }
    00726
    00737 static DiagDirection GetTileSingleEntry(TileIndex tile, TransportType type, uint subtype)
    00738 {
    00739   if (type != TRANSPORT_WATER && IsDepotTypeTile(tile, type)) return GetDepotDirection(tile, type);
    00740
    00741   if (type == TRANSPORT_ROAD) {
    00742     if (IsStandardRoadStopTile(tile)) return GetRoadStopDir(tile);
    00743     if (HasBit(subtype, ROADTYPE_TRAM)) return GetSingleTramBit(tile);
    00744   }
    00745
    00746   return INVALID_DIAGDIR;
    00747 }
    00748
    00758 static inline bool ForceReverse(TileIndex tile, DiagDirection dir, TransportType type, uint subtype)
    00759 {
    00760   DiagDirection single_entry = GetTileSingleEntry(tile, type, subtype);
    00761   return single_entry != INVALID_DIAGDIR && single_entry != dir;
    00762 }
    00763
    00775 static bool CanEnterTile(TileIndex tile, DiagDirection dir, TransportType type, uint subtype, RailTypes railtypes, Owner owner)
    00776 {
    00777   /* Check tunnel entries and bridge ramps */
    00778   if (IsTileType(tile, MP_TUNNELBRIDGE) && GetTunnelBridgeDirection(tile) != dir) return false;
    00779
    00780   /* Test ownership */
    00781   if (!CanEnterTileOwnerCheck(owner, tile, dir)) return false;
    00782
    00783   /* check correct rail type (mono, maglev, etc) */
    00784   if (type == TRANSPORT_RAIL) {
    00785     RailType rail_type = GetTileRailType(tile);
    00786     if (!HasBit(railtypes, rail_type)) return false;
    00787   }
    00788
    00789   /* Depots, standard roadstops and single tram bits can only be entered from one direction */
    00790   DiagDirection single_entry = GetTileSingleEntry(tile, type, subtype);
    00791   if (single_entry != INVALID_DIAGDIR && single_entry != ReverseDiagDir(dir)) return false;
    00792
    00793   return true;
    00794 }
    00795
    00807 static TrackdirBits GetDriveableTrackdirBits(TileIndex dst_tile, Trackdir src_trackdir, TransportType type, uint subtype)
    00808 {
    00809   TrackdirBits trackdirbits = TrackStatusToTrackdirBits(GetTileTrackStatus(dst_tile, type, subtype));
    00810
    00811   if (trackdirbits == 0 && type == TRANSPORT_ROAD && HasBit(subtype, ROADTYPE_TRAM)) {
    00812     /* GetTileTrackStatus() returns 0 for single tram bits.
    00813      * As we cannot change it there (easily) without breaking something, change it here */
    00814     switch (GetSingleTramBit(dst_tile)) {
    00815       case DIAGDIR_NE:
    00816       case DIAGDIR_SW:
    00817         trackdirbits = TRACKDIR_BIT_X_NE | TRACKDIR_BIT_X_SW;
    00818         break;
    00819
    00820       case DIAGDIR_NW:
    00821       case DIAGDIR_SE:
    00822         trackdirbits = TRACKDIR_BIT_Y_NW | TRACKDIR_BIT_Y_SE;
    00823         break;
    00824
    00825       default: break;
    00826     }
    00827   }
    00828
    00829   DEBUG(npf, 4, "Next node: (%d, %d) [%d], possible trackdirs: 0x%X", TileX(dst_tile), TileY(dst_tile), dst_tile, trackdirbits);
    00830
    00831   /* Select only trackdirs we can reach from our current trackdir */
    00832   trackdirbits &= TrackdirReachesTrackdirs(src_trackdir);
    00833
    00834   /* Filter out trackdirs that would make 90 deg turns for trains */
    00835   if (_settings_game.pf.forbid_90_deg && (type == TRANSPORT_RAIL || type == TRANSPORT_WATER)) trackdirbits &= ~TrackdirCrossesTrackdirs(src_trackdir);
    00836
    00837   DEBUG(npf, 6, "After filtering: (%d, %d), possible trackdirs: 0x%X", TileX(dst_tile), TileY(dst_tile), trackdirbits);
    00838
    00839   return trackdirbits;
    00840 }
    00841
    00842
    00843 /* Will just follow the results of GetTileTrackStatus concerning where we can
    00844  * go and where not. Uses AyStar.user_data[NPF_TYPE] as the transport type and
    00845  * an argument to GetTileTrackStatus. Will skip tunnels, meaning that the
    00846  * entry and exit are neighbours. Will fill
    00847  * AyStarNode.user_data[NPF_TRACKDIR_CHOICE] with an appropriate value, and
    00848  * copy AyStarNode.user_data[NPF_NODE_FLAGS] from the parent */
    00849 static void NPFFollowTrack(AyStar *aystar, OpenListNode *current)
    00850 {
    00851   /* We leave src_tile on track src_trackdir in direction src_exitdir */
    00852   Trackdir src_trackdir = current->path.node.direction;
    00853   TileIndex src_tile = current->path.node.tile;
    00854   DiagDirection src_exitdir = TrackdirToExitdir(src_trackdir);
    00855
    00856   /* Is src_tile valid, and can be used?
    00857    * When choosing track on a junction src_tile is the tile neighboured to the junction wrt. exitdir.
    00858    * But we must not check the validity of this move, as src_tile is totally unrelated to the move, if a roadvehicle reversed on a junction. */
    00859   bool ignore_src_tile = (current->path.parent == NULL && NPFGetFlag(&current->path.node, NPF_FLAG_IGNORE_START_TILE));
    00860
    00861   /* Information about the vehicle: TransportType (road/rail/water) and SubType (compatible rail/road types) */
    00862   TransportType type = (TransportType)aystar->user_data[NPF_TYPE];
    00863   uint subtype = aystar->user_data[NPF_SUB_TYPE];
    00864
    00865   /* Initialize to 0, so we can jump out (return) somewhere an have no neighbours */
    00866   aystar->num_neighbours = 0;
    00867   DEBUG(npf, 4, "Expanding: (%d, %d, %d) [%d]", TileX(src_tile), TileY(src_tile), src_trackdir, src_tile);
    00868
    00869   /* We want to determine the tile we arrive, and which choices we have there */
    00870   TileIndex dst_tile;
    00871   TrackdirBits trackdirbits;
    00872
    00873   /* Find dest tile */
    00874   if (ignore_src_tile) {
    00875     /* Do not perform any checks that involve src_tile */
    00876     dst_tile = src_tile + TileOffsByDiagDir(src_exitdir);
    00877     trackdirbits = GetDriveableTrackdirBits(dst_tile, src_trackdir, type, subtype);
    00878   } else if (IsTileType(src_tile, MP_TUNNELBRIDGE) && GetTunnelBridgeDirection(src_tile) == src_exitdir) {
    00879     /* We drive through the wormhole and arrive on the other side */
    00880     dst_tile = GetOtherTunnelBridgeEnd(src_tile);
    00881     trackdirbits = TrackdirToTrackdirBits(src_trackdir);
    00882   } else if (ForceReverse(src_tile, src_exitdir, type, subtype)) {
    00883     /* We can only reverse on this tile */
    00884     dst_tile = src_tile;
    00885     src_trackdir = ReverseTrackdir(src_trackdir);
    00886     trackdirbits = TrackdirToTrackdirBits(src_trackdir);
    00887   } else {
    00888     /* We leave src_tile in src_exitdir and reach dst_tile */
    00889     dst_tile = AddTileIndexDiffCWrap(src_tile, TileIndexDiffCByDiagDir(src_exitdir));
    00890
    00891     if (dst_tile != INVALID_TILE && !CanEnterTile(dst_tile, src_exitdir, type, subtype, (RailTypes)aystar->user_data[NPF_RAILTYPES], (Owner)aystar->user_data[NPF_OWNER])) dst_tile = INVALID_TILE;
    00892
    00893     if (dst_tile == INVALID_TILE) {
    00894       /* We cannot enter the next tile. Road vehicles can reverse, others reach dead end */
    00895       if (type != TRANSPORT_ROAD || HasBit(subtype, ROADTYPE_TRAM)) return;
    00896
    00897       dst_tile = src_tile;
    00898       src_trackdir = ReverseTrackdir(src_trackdir);
    00899     }
    00900
    00901     trackdirbits = GetDriveableTrackdirBits(dst_tile, src_trackdir, type, subtype);
    00902
    00903     if (trackdirbits == 0) {
    00904       /* We cannot enter the next tile. Road vehicles can reverse, others reach dead end */
    00905       if (type != TRANSPORT_ROAD || HasBit(subtype, ROADTYPE_TRAM)) return;
    00906
    00907       dst_tile = src_tile;
    00908       src_trackdir = ReverseTrackdir(src_trackdir);
    00909
    00910       trackdirbits = GetDriveableTrackdirBits(dst_tile, src_trackdir, type, subtype);
    00911     }
    00912   }
    00913
    00914   if (NPFGetFlag(&current->path.node, NPF_FLAG_IGNORE_RESERVED)) {
    00915     /* Mask out any reserved tracks. */
    00916     TrackBits reserved = GetReservedTrackbits(dst_tile);
    00917     trackdirbits &= ~TrackBitsToTrackdirBits(reserved);
    00918
    00919     Track t;
    00920     FOR_EACH_SET_TRACK(t, TrackdirBitsToTrackBits(trackdirbits)) {
    00921       if (TracksOverlap(reserved | TrackToTrackBits(t))) trackdirbits &= ~TrackToTrackdirBits(t);
    00922     }
    00923   }
    00924
    00925   /* Enumerate possible track */
    00926   uint i = 0;
    00927   while (trackdirbits != 0) {
    00928     Trackdir dst_trackdir = RemoveFirstTrackdir(&trackdirbits);
    00929     DEBUG(npf, 5, "Expanded into trackdir: %d, remaining trackdirs: 0x%X", dst_trackdir, trackdirbits);
    00930
    00931     /* Tile with signals? */
    00932     if (IsTileType(dst_tile, MP_RAILWAY) && GetRailTileType(dst_tile) == RAIL_TILE_SIGNALS) {
    00933       if (HasSignalOnTrackdir(dst_tile, ReverseTrackdir(dst_trackdir)) && !HasSignalOnTrackdir(dst_tile, dst_trackdir) && IsOnewaySignal(dst_tile, TrackdirToTrack(dst_trackdir))) {
    00934         /* If there's a one-way signal not pointing towards us, stop going in this direction. */
    00935         break;
    00936       }
    00937     }
    00938     {
    00939       /* We've found ourselves a neighbour :-) */
    00940       AyStarNode *neighbour = &aystar->neighbours[i];
    00941       neighbour->tile = dst_tile;
    00942       neighbour->direction = dst_trackdir;
    00943       /* Save user data */
    00944       neighbour->user_data[NPF_NODE_FLAGS] = current->path.node.user_data[NPF_NODE_FLAGS];
    00945       NPFFillTrackdirChoice(neighbour, current);
    00946     }
    00947     i++;
    00948   }
    00949   aystar->num_neighbours = i;
    00950 }
    00951
    00952 /*
    00953  * Plan a route to the specified target (which is checked by target_proc),
    00954  * from start1 and if not NULL, from start2 as well. The type of transport we
    00955  * are checking is in type. reverse_penalty is applied to all routes that
    00956  * originate from the second start node.
    00957  * When we are looking for one specific target (optionally multiple tiles), we
    00958  * should use a good heuristic to perform aystar search. When we search for
    00959  * multiple targets that are spread around, we should perform a breadth first
    00960  * search by specifiying CalcZero as our heuristic.
    00961  */
    00962 static NPFFoundTargetData NPFRouteInternal(AyStarNode *start1, bool ignore_start_tile1, AyStarNode *start2, bool ignore_start_tile2, NPFFindStationOrTileData *target, AyStar_EndNodeCheck target_proc, AyStar_CalculateH heuristic_proc, TransportType type, uint sub_type, Owner owner, RailTypes railtypes, uint reverse_penalty)
    00963 {
    00964   int r;
    00965   NPFFoundTargetData result;
    00966
    00967   /* Initialize procs */
    00968   _npf_aystar.CalculateH = heuristic_proc;
    00969   _npf_aystar.EndNodeCheck = target_proc;
    00970   _npf_aystar.FoundEndNode = NPFSaveTargetData;
    00971   _npf_aystar.GetNeighbours = NPFFollowTrack;
    00972   switch (type) {
    00973     default: NOT_REACHED();
    00974     case TRANSPORT_RAIL:  _npf_aystar.CalculateG = NPFRailPathCost;  break;
    00975     case TRANSPORT_ROAD:  _npf_aystar.CalculateG = NPFRoadPathCost;  break;
    00976     case TRANSPORT_WATER: _npf_aystar.CalculateG = NPFWaterPathCost; break;
    00977   }
    00978
    00979   /* Initialize Start Node(s) */
    00980   start1->user_data[NPF_TRACKDIR_CHOICE] = INVALID_TRACKDIR;
    00981   start1->user_data[NPF_NODE_FLAGS] = 0;
    00982   NPFSetFlag(start1, NPF_FLAG_IGNORE_START_TILE, ignore_start_tile1);
    00983   _npf_aystar.AddStartNode(start1, 0);
    00984   if (start2) {
    00985     start2->user_data[NPF_TRACKDIR_CHOICE] = INVALID_TRACKDIR;
    00986     start2->user_data[NPF_NODE_FLAGS] = 0;
    00987     NPFSetFlag(start2, NPF_FLAG_IGNORE_START_TILE, ignore_start_tile2);
    00988     NPFSetFlag(start2, NPF_FLAG_REVERSE, true);
    00989     _npf_aystar.AddStartNode(start2, reverse_penalty);
    00990   }
    00991
    00992   /* Initialize result */
    00993   result.best_bird_dist = UINT_MAX;
    00994   result.best_path_dist = UINT_MAX;
    00995   result.best_trackdir  = INVALID_TRACKDIR;
    00996   result.node.tile      = INVALID_TILE;
    00997   result.res_okay       = false;
    00998   _npf_aystar.user_path = &result;
    00999
    01000   /* Initialize target */
    01001   _npf_aystar.user_target = target;
    01002
    01003   /* Initialize user_data */
    01004   _npf_aystar.user_data[NPF_TYPE] = type;
    01005   _npf_aystar.user_data[NPF_SUB_TYPE] = sub_type;
    01006   _npf_aystar.user_data[NPF_OWNER] = owner;
    01007   _npf_aystar.user_data[NPF_RAILTYPES] = railtypes;
    01008
    01009   /* GO! */
    01010   r = _npf_aystar.Main();
    01011   assert(r != AYSTAR_STILL_BUSY);
    01012
    01013   if (result.best_bird_dist != 0) {
    01014     if (target != NULL) {
    01015       DEBUG(npf, 1, "Could not find route to tile 0x%X from 0x%X.", target->dest_coords, start1->tile);
    01016     } else {
    01017       /* Assumption: target == NULL, so we are looking for a depot */
    01018       DEBUG(npf, 1, "Could not find route to a depot from tile 0x%X.", start1->tile);
    01019     }
    01020
    01021   }
    01022   return result;
    01023 }
    01024
    01025 /* Will search as below, but with two start nodes, the second being the
    01026  * reverse. Look at the NPF_FLAG_REVERSE flag in the result node to see which
    01027  * direction was taken (NPFGetFlag(result.node, NPF_FLAG_REVERSE)) */
    01028 static NPFFoundTargetData NPFRouteToStationOrTileTwoWay(TileIndex tile1, Trackdir trackdir1, bool ignore_start_tile1, TileIndex tile2, Trackdir trackdir2, bool ignore_start_tile2, NPFFindStationOrTileData *target, TransportType type, uint sub_type, Owner owner, RailTypes railtypes)
    01029 {
    01030   AyStarNode start1;
    01031   AyStarNode start2;
    01032
    01033   start1.tile = tile1;
    01034   start2.tile = tile2;
    01035   /* We set this in case the target is also the start tile, we will just
    01036    * return a not found then */
    01037   start1.user_data[NPF_TRACKDIR_CHOICE] = INVALID_TRACKDIR;
    01038   start1.direction = trackdir1;
    01039   start2.direction = trackdir2;
    01040   start2.user_data[NPF_TRACKDIR_CHOICE] = INVALID_TRACKDIR;
    01041
    01042   return NPFRouteInternal(&start1, ignore_start_tile1, (IsValidTile(tile2) ? &start2 : NULL), ignore_start_tile2, target, NPFFindStationOrTile, NPFCalcStationOrTileHeuristic, type, sub_type, owner, railtypes, 0);
    01043 }
    01044
    01045 /* Will search from the given tile and direction, for a route to the given
    01046  * station for the given transport type. See the declaration of
    01047  * NPFFoundTargetData above for the meaning of the result. */
    01048 static NPFFoundTargetData NPFRouteToStationOrTile(TileIndex tile, Trackdir trackdir, bool ignore_start_tile, NPFFindStationOrTileData *target, TransportType type, uint sub_type, Owner owner, RailTypes railtypes)
    01049 {
    01050   return NPFRouteToStationOrTileTwoWay(tile, trackdir, ignore_start_tile, INVALID_TILE, INVALID_TRACKDIR, false, target, type, sub_type, owner, railtypes);
    01051 }
    01052
    01053 /* Search using breadth first. Good for little track choice and inaccurate
    01054  * heuristic, such as railway/road with two start nodes, the second being the reverse. Call
    01055  * NPFGetFlag(result.node, NPF_FLAG_REVERSE) to see from which node the path
    01056  * orginated. All pathfs from the second node will have the given
    01057  * reverse_penalty applied (NPF_TILE_LENGTH is the equivalent of one full
    01058  * tile).
    01059  */
    01060 static NPFFoundTargetData NPFRouteToDepotBreadthFirstTwoWay(TileIndex tile1, Trackdir trackdir1, bool ignore_start_tile1, TileIndex tile2, Trackdir trackdir2, bool ignore_start_tile2, NPFFindStationOrTileData *target, TransportType type, uint sub_type, Owner owner, RailTypes railtypes, uint reverse_penalty)
    01061 {
    01062   AyStarNode start1;
    01063   AyStarNode start2;
    01064
    01065   start1.tile = tile1;
    01066   start2.tile = tile2;
    01067   /* We set this in case the target is also the start tile, we will just
    01068    * return a not found then */
    01069   start1.user_data[NPF_TRACKDIR_CHOICE] = INVALID_TRACKDIR;
    01070   start1.direction = trackdir1;
    01071   start2.direction = trackdir2;
    01072   start2.user_data[NPF_TRACKDIR_CHOICE] = INVALID_TRACKDIR;
    01073
    01074   /* perform a breadth first search. Target is NULL,
    01075    * since we are just looking for any depot...*/
    01076   return NPFRouteInternal(&start1, ignore_start_tile1, (IsValidTile(tile2) ? &start2 : NULL), ignore_start_tile2, target, NPFFindDepot, NPFCalcZero, type, sub_type, owner, railtypes, reverse_penalty);
    01077 }
    01078
    01079 void InitializeNPF()
    01080 {
    01081   static bool first_init = true;
    01082   if (first_init) {
    01083     first_init = false;
    01084     _npf_aystar.Init(NPFHash, NPF_HASH_SIZE);
    01085   } else {
    01086     _npf_aystar.Clear();
    01087   }
    01088   _npf_aystar.loops_per_tick = 0;
    01089   _npf_aystar.max_path_cost = 0;
    01090   //_npf_aystar.max_search_nodes = 0;
    01091   /* We will limit the number of nodes for now, until we have a better
    01092    * solution to really fix performance */
    01093   _npf_aystar.max_search_nodes = _settings_game.pf.npf.npf_max_search_nodes;
    01094 }
    01095
    01096 static void NPFFillWithOrderData(NPFFindStationOrTileData *fstd, const Vehicle *v, bool reserve_path = false)
    01097 {
    01098   /* Ships don't really reach their stations, but the tile in front. So don't
    01099    * save the station id for ships. For roadvehs we don't store it either,
    01100    * because multistop depends on vehicles actually reaching the exact
    01101    * dest_tile, not just any stop of that station.
    01102    * So only for train orders to stations we fill fstd->station_index, for all
    01103    * others only dest_coords */
    01104   if (v->type != VEH_SHIP && (v->current_order.IsType(OT_GOTO_STATION) || v->current_order.IsType(OT_GOTO_WAYPOINT))) {
    01105     assert(v->IsGroundVehicle());
    01106     fstd->station_index = v->current_order.GetDestination();
    01107     fstd->station_type = (v->type == VEH_TRAIN) ? (v->current_order.IsType(OT_GOTO_STATION) ? STATION_RAIL : STATION_WAYPOINT) : (RoadVehicle::From(v)->IsBus() ? STATION_BUS : STATION_TRUCK);
    01108     fstd->not_articulated = v->type == VEH_ROAD && !RoadVehicle::From(v)->HasArticulatedPart();
    01109     /* Let's take the closest tile of the station as our target for vehicles */
    01110     fstd->dest_coords = CalcClosestStationTile(fstd->station_index, v->tile, fstd->station_type);
    01111   } else {
    01112     fstd->dest_coords = v->dest_tile;
    01113     fstd->station_index = INVALID_STATION;
    01114   }
    01115   fstd->reserve_path = reserve_path;
    01116   fstd->v = v;
    01117 }
    01118
    01119 /*** Road vehicles ***/
    01120
    01121 FindDepotData NPFRoadVehicleFindNearestDepot(const RoadVehicle *v, int max_penalty)
    01122 {
    01123   Trackdir trackdir = v->GetVehicleTrackdir();
    01124
    01125   NPFFoundTargetData ftd = NPFRouteToDepotBreadthFirstTwoWay(v->tile, trackdir, false, v->tile, ReverseTrackdir(trackdir), false, NULL, TRANSPORT_ROAD, v->compatible_roadtypes, v->owner, INVALID_RAILTYPES, 0);
    01126
    01127   if (ftd.best_bird_dist != 0) return FindDepotData();
    01128
    01129   /* Found target */
    01130   /* Our caller expects a number of tiles, so we just approximate that
    01131    * number by this. It might not be completely what we want, but it will
    01132    * work for now :-) We can possibly change this when the old pathfinder
    01133    * is removed. */
    01134   return FindDepotData(ftd.node.tile, ftd.best_path_dist);
    01135 }
    01136
    01137 Trackdir NPFRoadVehicleChooseTrack(const RoadVehicle *v, TileIndex tile, DiagDirection enterdir, TrackdirBits trackdirs, bool &path_found)
    01138 {
    01139   NPFFindStationOrTileData fstd;
    01140
    01141   NPFFillWithOrderData(&fstd, v);
    01142   Trackdir trackdir = DiagDirToDiagTrackdir(enterdir);
    01143
    01144   NPFFoundTargetData ftd = NPFRouteToStationOrTile(tile - TileOffsByDiagDir(enterdir), trackdir, true, &fstd, TRANSPORT_ROAD, v->compatible_roadtypes, v->owner, INVALID_RAILTYPES);
    01145   if (ftd.best_trackdir == INVALID_TRACKDIR) {
    01146     /* We are already at our target. Just do something
    01147      * @todo: maybe display error?
    01148      * @todo: go straight ahead if possible? */
    01149     path_found = true;
    01150     return (Trackdir)FindFirstBit2x64(trackdirs);
    01151   }
    01152
    01153   /* If ftd.best_bird_dist is 0, we found our target and ftd.best_trackdir contains
    01154    * the direction we need to take to get there, if ftd.best_bird_dist is not 0,
    01155    * we did not find our target, but ftd.best_trackdir contains the direction leading
    01156    * to the tile closest to our target. */
    01157   path_found = (ftd.best_bird_dist == 0);
    01158   return ftd.best_trackdir;
    01159 }
    01160
    01161 /*** Ships ***/
    01162
    01163 Track NPFShipChooseTrack(const Ship *v, TileIndex tile, DiagDirection enterdir, TrackBits tracks, bool &path_found)
    01164 {
    01165   NPFFindStationOrTileData fstd;
    01166   Trackdir trackdir = v->GetVehicleTrackdir();
    01167   assert(trackdir != INVALID_TRACKDIR); // Check that we are not in a depot
    01168
    01169   NPFFillWithOrderData(&fstd, v);
    01170
    01171   NPFFoundTargetData ftd = NPFRouteToStationOrTile(tile - TileOffsByDiagDir(enterdir), trackdir, true, &fstd, TRANSPORT_WATER, 0, v->owner, INVALID_RAILTYPES);
    01172
    01173   /* If ftd.best_bird_dist is 0, we found our target and ftd.best_trackdir contains
    01174    * the direction we need to take to get there, if ftd.best_bird_dist is not 0,
    01175    * we did not find our target, but ftd.best_trackdir contains the direction leading
    01176    * to the tile closest to our target. */
    01177   path_found = (ftd.best_bird_dist == 0);
    01178   if (ftd.best_trackdir == 0xff) return INVALID_TRACK;
    01179   return TrackdirToTrack(ftd.best_trackdir);
    01180 }
    01181
    01182 /*** Trains ***/
    01183
    01184 FindDepotData NPFTrainFindNearestDepot(const Train *v, int max_penalty)
    01185 {
    01186   const Train *last = v->Last();
    01187   Trackdir trackdir = v->GetVehicleTrackdir();
    01188   Trackdir trackdir_rev = ReverseTrackdir(last->GetVehicleTrackdir());
    01189   NPFFindStationOrTileData fstd;
    01190   fstd.v = v;
    01191   fstd.reserve_path = false;
    01192
    01193   assert(trackdir != INVALID_TRACKDIR);
    01194   NPFFoundTargetData ftd = NPFRouteToDepotBreadthFirstTwoWay(v->tile, trackdir, false, last->tile, trackdir_rev, false, &fstd, TRANSPORT_RAIL, 0, v->owner, v->compatible_railtypes, NPF_INFINITE_PENALTY);
    01195   if (ftd.best_bird_dist != 0) return FindDepotData();
    01196
    01197   /* Found target */
    01198   /* Our caller expects a number of tiles, so we just approximate that
    01199    * number by this. It might not be completely what we want, but it will
    01200    * work for now :-) We can possibly change this when the old pathfinder
    01201    * is removed. */
    01202   return FindDepotData(ftd.node.tile, ftd.best_path_dist, NPFGetFlag(&ftd.node, NPF_FLAG_REVERSE));
    01203 }
    01204
    01205 bool NPFTrainFindNearestSafeTile(const Train *v, TileIndex tile, Trackdir trackdir, bool override_railtype)
    01206 {
    01207   assert(v->type == VEH_TRAIN);
    01208
    01209   NPFFindStationOrTileData fstd;
    01210   fstd.v = v;
    01211   fstd.reserve_path = true;
    01212
    01213   AyStarNode start1;
    01214   start1.tile = tile;
    01215   /* We set this in case the target is also the start tile, we will just
    01216    * return a not found then */
    01217   start1.user_data[NPF_TRACKDIR_CHOICE] = INVALID_TRACKDIR;
    01218   start1.direction = trackdir;
    01219   NPFSetFlag(&start1, NPF_FLAG_IGNORE_RESERVED, true);
    01220
    01221   RailTypes railtypes = v->compatible_railtypes;
    01222   if (override_railtype) railtypes |= GetRailTypeInfo(v->railtype)->compatible_railtypes;
    01223
    01224   /* perform a breadth first search. Target is NULL,
    01225    * since we are just looking for any safe tile...*/
    01226   return NPFRouteInternal(&start1, true, NULL, false, &fstd, NPFFindSafeTile, NPFCalcZero, TRANSPORT_RAIL, 0, v->owner, railtypes, 0).res_okay;
    01227 }
    01228
    01229 bool NPFTrainCheckReverse(const Train *v)
    01230 {
    01231   NPFFindStationOrTileData fstd;
    01232   NPFFoundTargetData ftd;
    01233   const Train *last = v->Last();
    01234
    01235   NPFFillWithOrderData(&fstd, v);
    01236
    01237   Trackdir trackdir = v->GetVehicleTrackdir();
    01238   Trackdir trackdir_rev = ReverseTrackdir(last->GetVehicleTrackdir());
    01239   assert(trackdir != INVALID_TRACKDIR);
    01240   assert(trackdir_rev != INVALID_TRACKDIR);
    01241
    01242   ftd = NPFRouteToStationOrTileTwoWay(v->tile, trackdir, false, last->tile, trackdir_rev, false, &fstd, TRANSPORT_RAIL, 0, v->owner, v->compatible_railtypes);
    01243   /* If we didn't find anything, just keep on going straight ahead, otherwise take the reverse flag */
    01244   return ftd.best_bird_dist != 0 && NPFGetFlag(&ftd.node, NPF_FLAG_REVERSE);
    01245 }
    01246
    01247 Track NPFTrainChooseTrack(const Train *v, TileIndex tile, DiagDirection enterdir, TrackBits tracks, bool &path_found, bool reserve_track, struct PBSTileInfo *target)
    01248 {
    01249   NPFFindStationOrTileData fstd;
    01250   NPFFillWithOrderData(&fstd, v, reserve_track);
    01251
    01252   PBSTileInfo origin = FollowTrainReservation(v);
    01253   assert(IsValidTrackdir(origin.trackdir));
    01254
    01255   NPFFoundTargetData ftd = NPFRouteToStationOrTile(origin.tile, origin.trackdir, true, &fstd, TRANSPORT_RAIL, 0, v->owner, v->compatible_railtypes);
    01256
    01257   if (target != NULL) {
    01258     target->tile = ftd.node.tile;
    01259     target->trackdir = (Trackdir)ftd.node.direction;
    01260     target->okay = ftd.res_okay;
    01261   }
    01262
    01263   if (ftd.best_trackdir == INVALID_TRACKDIR) {
    01264     /* We are already at our target. Just do something
    01265      * @todo maybe display error?
    01266      * @todo: go straight ahead if possible? */
    01267     path_found = true;
    01268     return FindFirstTrack(tracks);
    01269   }
    01270
    01271   /* If ftd.best_bird_dist is 0, we found our target and ftd.best_trackdir contains
    01272    * the direction we need to take to get there, if ftd.best_bird_dist is not 0,
    01273    * we did not find our target, but ftd.best_trackdir contains the direction leading
    01274    * to the tile closest to our target. */
    01275   path_found = (ftd.best_bird_dist == 0);
    01276   /* Discard enterdir information, making it a normal track */
    01277   return TrackdirToTrack(ftd.best_trackdir);
    01278 }