# 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 "../../landscape.h"
    00015 #include "../../depot_base.h"
    00016 #include "../../network/network.h"
    00017 #include "../../tunnelbridge_map.h"
    00018 #include "../../functions.h"
    00019 #include "../../tunnelbridge.h"
    00020 #include "../../pbs.h"
    00021 #include "../../roadveh.h"
    00022 #include "../../ship.h"
    00023 #include "../../train.h"
    00024 #include "../../roadstop_base.h"
    00025 #include "../../infrastructure_func.h"
    00026 #include "../pathfinder_func.h"
    00027 #include "../pathfinder_type.h"
    00028 #include "../follow_track.hpp"
    00029 #include "aystar.h"
    00030
    00031 enum {
    00032   NPF_HASH_BITS = 12,
    00033   /* Do no change below values */
    00034   NPF_HASH_SIZE = 1 << NPF_HASH_BITS,
    00035   NPF_HASH_HALFBITS = NPF_HASH_BITS / 2,
    00036   NPF_HASH_HALFMASK = (1 << NPF_HASH_HALFBITS) - 1
    00037 };
    00038
    00039 /* Meant to be stored in AyStar.targetdata */
    00040 struct NPFFindStationOrTileData {
    00041   TileIndex dest_coords;
    00042   StationID station_index;
    00043   bool reserve_path;
    00044   StationType station_type;
    00045   bool not_articulated;
    00046   const Vehicle *v;
    00047 };
    00048
    00049 /* Indices into AyStar.userdata[] */
    00050 enum {
    00051   NPF_TYPE = 0,
    00052   NPF_SUB_TYPE,
    00053   NPF_OWNER,
    00054   NPF_RAILTYPES,
    00055 };
    00056
    00057 /* Indices into AyStarNode.userdata[] */
    00058 enum {
    00059   NPF_TRACKDIR_CHOICE = 0,
    00060   NPF_NODE_FLAGS,
    00061 };
    00062
    00063 /* Flags for AyStarNode.userdata[NPF_NODE_FLAGS]. Use NPFSetFlag() and NPFGetFlag() to use them. */
    00064 enum NPFNodeFlag {
    00065   NPF_FLAG_SEEN_SIGNAL,
    00066   NPF_FLAG_2ND_SIGNAL,
    00067   NPF_FLAG_3RD_SIGNAL,
    00068   NPF_FLAG_REVERSE,
    00069   NPF_FLAG_LAST_SIGNAL_RED,
    00070   NPF_FLAG_LAST_SIGNAL_BLOCK,
    00071   NPF_FLAG_IGNORE_START_TILE,
    00072   NPF_FLAG_TARGET_RESERVED,
    00073   NPF_FLAG_IGNORE_RESERVED,
    00074 };
    00075
    00076 /* Meant to be stored in AyStar.userpath */
    00077 struct NPFFoundTargetData {
    00078   uint best_bird_dist;
    00079   uint best_path_dist;
    00080   Trackdir best_trackdir;
    00081   AyStarNode node;
    00082   bool res_okay;
    00083 };
    00084
    00085 static AyStar _npf_aystar;
    00086
    00087 /* The cost of each trackdir. A diagonal piece is the full NPF_TILE_LENGTH,
    00088  * the shorter piece is sqrt(2)/2*NPF_TILE_LENGTH =~ 0.7071
    00089  */
    00090 #define NPF_STRAIGHT_LENGTH (uint)(NPF_TILE_LENGTH * STRAIGHT_TRACK_LENGTH)
    00091 static const uint _trackdir_length[TRACKDIR_END] = {
    00092   NPF_TILE_LENGTH, NPF_TILE_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH,
    00093   0, 0,
    00094   NPF_TILE_LENGTH, NPF_TILE_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH
    00095 };
    00096
    00100 static inline bool NPFGetFlag(const AyStarNode *node, NPFNodeFlag flag)
    00101 {
    00102   return HasBit(node->user_data[NPF_NODE_FLAGS], flag);
    00103 }
    00104
    00108 static inline void NPFSetFlag(AyStarNode *node, NPFNodeFlag flag, bool value)
    00109 {
    00110   SB(node->user_data[NPF_NODE_FLAGS], flag, 1, value);
    00111 }
    00112
    00119 static uint NPFDistanceTrack(TileIndex t0, TileIndex t1)
    00120 {
    00121   const uint dx = Delta(TileX(t0), TileX(t1));
    00122   const uint dy = Delta(TileY(t0), TileY(t1));
    00123
    00124   const uint straightTracks = 2 * min(dx, dy); // The number of straight (not full length) tracks
    00125   /* OPTIMISATION:
    00126    * Original: diagTracks = max(dx, dy) - min(dx,dy);
    00127    * Proof:
    00128    * (dx+dy) - straightTracks  == (min + max) - straightTracks = min + max - 2 * min = max - min */
    00129   const uint diagTracks = dx + dy - straightTracks; // The number of diagonal (full tile length) tracks.
    00130
    00131   /* Don't factor out NPF_TILE_LENGTH below, this will round values and lose
    00132    * precision */
    00133   return diagTracks * NPF_TILE_LENGTH + straightTracks * NPF_TILE_LENGTH * STRAIGHT_TRACK_LENGTH;
    00134 }
    00135
    00136
    00137 #if 0
    00138 static uint NTPHash(uint key1, uint key2)
    00139 {
    00140   /* This function uses the old hash, which is fixed on 10 bits (1024 buckets) */
    00141   return PATHFIND_HASH_TILE(key1);
    00142 }
    00143 #endif
    00144
    00152 static uint NPFHash(uint key1, uint key2)
    00153 {
    00154   /* TODO: think of a better hash? */
    00155   uint part1 = TileX(key1) & NPF_HASH_HALFMASK;
    00156   uint part2 = TileY(key1) & NPF_HASH_HALFMASK;
    00157
    00158   assert(IsValidTrackdir((Trackdir)key2));
    00159   assert(IsValidTile(key1));
    00160   return ((part1 << NPF_HASH_HALFBITS | part2) + (NPF_HASH_SIZE * key2 / TRACKDIR_END)) % NPF_HASH_SIZE;
    00161 }
    00162
    00163 static int32 NPFCalcZero(AyStar *as, AyStarNode *current, OpenListNode *parent)
    00164 {
    00165   return 0;
    00166 }
    00167
    00168 /* Calcs the heuristic to the target station or tile. For train stations, it
    00169  * takes into account the direction of approach.
    00170  */
    00171 static int32 NPFCalcStationOrTileHeuristic(AyStar *as, AyStarNode *current, OpenListNode *parent)
    00172 {
    00173   NPFFindStationOrTileData *fstd = (NPFFindStationOrTileData*)as->user_target;
    00174   NPFFoundTargetData *ftd = (NPFFoundTargetData*)as->user_path;
    00175   TileIndex from = current->tile;
    00176   TileIndex to = fstd->dest_coords;
    00177   uint dist;
    00178
    00179   /* for train-stations, we are going to aim for the closest station tile */
    00180   if (as->user_data[NPF_TYPE] != TRANSPORT_WATER && fstd->station_index != INVALID_STATION)
    00181     to = CalcClosestStationTile(fstd->station_index, from, fstd->station_type);
    00182
    00183   if (as->user_data[NPF_TYPE] == TRANSPORT_ROAD) {
    00184     /* Since roads only have diagonal pieces, we use manhattan distance here */
    00185     dist = DistanceManhattan(from, to) * NPF_TILE_LENGTH;
    00186   } else {
    00187     /* Ships and trains can also go diagonal, so the minimum distance is shorter */
    00188     dist = NPFDistanceTrack(from, to);
    00189   }
    00190
    00191   DEBUG(npf, 4, "Calculating H for: (%d, %d). Result: %d", TileX(current->tile), TileY(current->tile), dist);
    00192
    00193   if (dist < ftd->best_bird_dist) {
    00194     ftd->best_bird_dist = dist;
    00195     ftd->best_trackdir = (Trackdir)current->user_data[NPF_TRACKDIR_CHOICE];
    00196   }
    00197   return dist;
    00198 }
    00199
    00200
    00201 /* Fills AyStarNode.user_data[NPF_TRACKDIRCHOICE] with the chosen direction to
    00202  * get here, either getting it from the current choice or from the parent's
    00203  * choice */
    00204 static void NPFFillTrackdirChoice(AyStarNode *current, OpenListNode *parent)
    00205 {
    00206   if (parent->path.parent == NULL) {
    00207     Trackdir trackdir = current->direction;
    00208     /* This is a first order decision, so we'd better save the
    00209      * direction we chose */
    00210     current->user_data[NPF_TRACKDIR_CHOICE] = trackdir;
    00211     DEBUG(npf, 6, "Saving trackdir: 0x%X", trackdir);
    00212   } else {
    00213     /* We've already made the decision, so just save our parent's decision */
    00214     current->user_data[NPF_TRACKDIR_CHOICE] = parent->path.node.user_data[NPF_TRACKDIR_CHOICE];
    00215   }
    00216 }
    00217
    00218 /* Will return the cost of the tunnel. If it is an entry, it will return the
    00219  * cost of that tile. If the tile is an exit, it will return the tunnel length
    00220  * including the exit tile. Requires that this is a Tunnel tile */
    00221 static uint NPFTunnelCost(AyStarNode *current)
    00222 {
    00223   DiagDirection exitdir = TrackdirToExitdir(current->direction);
    00224   TileIndex tile = current->tile;
    00225   if (GetTunnelBridgeDirection(tile) == ReverseDiagDir(exitdir)) {
    00226     /* We just popped out if this tunnel, since were
    00227      * facing the tunnel exit */
    00228     return NPF_TILE_LENGTH * (GetTunnelBridgeLength(current->tile, GetOtherTunnelEnd(current->tile)) + 1);
    00229     /* @todo: Penalty for tunnels? */
    00230   } else {
    00231     /* We are entering the tunnel, the enter tile is just a
    00232      * straight track */
    00233     return NPF_TILE_LENGTH;
    00234   }
    00235 }
    00236
    00237 static inline uint NPFBridgeCost(AyStarNode *current)
    00238 {
    00239   return NPF_TILE_LENGTH * GetTunnelBridgeLength(current->tile, GetOtherBridgeEnd(current->tile));
    00240 }
    00241
    00242 static uint NPFSlopeCost(AyStarNode *current)
    00243 {
    00244   TileIndex next = current->tile + TileOffsByDiagDir(TrackdirToExitdir(current->direction));
    00245
    00246   /* Get center of tiles */
    00247   int x1 = TileX(current->tile) * TILE_SIZE + TILE_SIZE / 2;
    00248   int y1 = TileY(current->tile) * TILE_SIZE + TILE_SIZE / 2;
    00249   int x2 = TileX(next) * TILE_SIZE + TILE_SIZE / 2;
    00250   int y2 = TileY(next) * TILE_SIZE + TILE_SIZE / 2;
    00251
    00252   int dx4 = (x2 - x1) / 4;
    00253   int dy4 = (y2 - y1) / 4;
    00254
    00255   /* Get the height on both sides of the tile edge.
    00256    * Avoid testing the height on the tile-center. This will fail for halftile-foundations.
    00257    */
    00258   int z1 = GetSlopeZ(x1 + dx4, y1 + dy4);
    00259   int z2 = GetSlopeZ(x2 - dx4, y2 - dy4);
    00260
    00261   if (z2 - z1 > 1) {
    00262     /* Slope up */
    00263     return _settings_game.pf.npf.npf_rail_slope_penalty;
    00264   }
    00265   return 0;
    00266   /* Should we give a bonus for slope down? Probably not, we
    00267    * could just substract that bonus from the penalty, because
    00268    * there is only one level of steepness... */
    00269 }
    00270
    00271 static uint NPFReservedTrackCost(AyStarNode *current)
    00272 {
    00273   TileIndex tile = current->tile;
    00274   TrackBits track = TrackToTrackBits(TrackdirToTrack(current->direction));
    00275   TrackBits res = GetReservedTrackbits(tile);
    00276
    00277   if (NPFGetFlag(current, NPF_FLAG_3RD_SIGNAL) || NPFGetFlag(current, NPF_FLAG_LAST_SIGNAL_BLOCK) || ((res & track) == TRACK_BIT_NONE && !TracksOverlap(res | track))) return 0;
    00278
    00279   if (IsTileType(tile, MP_TUNNELBRIDGE)) {
    00280     DiagDirection exitdir = TrackdirToExitdir(current->direction);
    00281     if (GetTunnelBridgeDirection(tile) == ReverseDiagDir(exitdir)) {
    00282       return  _settings_game.pf.npf.npf_rail_pbs_cross_penalty * (GetTunnelBridgeLength(tile, GetOtherTunnelBridgeEnd(tile)) + 1);
    00283     }
    00284   }
    00285   return  _settings_game.pf.npf.npf_rail_pbs_cross_penalty;
    00286 }
    00287
    00292 static void NPFMarkTile(TileIndex tile)
    00293 {
    00294 #ifndef NO_DEBUG_MESSAGES
    00295   if (_debug_npf_level < 1 || _networking) return;
    00296   switch (GetTileType(tile)) {
    00297     case MP_RAILWAY:
    00298       /* DEBUG: mark visited tiles by mowing the grass under them ;-) */
    00299       if (!IsRailDepot(tile)) {
    00300         SetRailGroundType(tile, RAIL_GROUND_BARREN);
    00301         MarkTileDirtyByTile(tile);
    00302       }
    00303       break;
    00304
    00305     case MP_ROAD:
    00306       if (!IsRoadDepot(tile)) {
    00307         SetRoadside(tile, ROADSIDE_BARREN);
    00308         MarkTileDirtyByTile(tile);
    00309       }
    00310       break;
    00311
    00312     default:
    00313       break;
    00314   }
    00315 #endif
    00316 }
    00317
    00318 static int32 NPFWaterPathCost(AyStar *as, AyStarNode *current, OpenListNode *parent)
    00319 {
    00320   /* TileIndex tile = current->tile; */
    00321   int32 cost = 0;
    00322   Trackdir trackdir = current->direction;
    00323
    00324   cost = _trackdir_length[trackdir]; // Should be different for diagonal tracks
    00325
    00326   if (IsBuoyTile(current->tile) && IsDiagonalTrackdir(trackdir))
    00327     cost += _settings_game.pf.npf.npf_buoy_penalty; // A small penalty for going over buoys
    00328
    00329   if (current->direction != NextTrackdir((Trackdir)parent->path.node.direction))
    00330     cost += _settings_game.pf.npf.npf_water_curve_penalty;
    00331
    00332   /* @todo More penalties? */
    00333
    00334   return cost;
    00335 }
    00336
    00337 /* Determine the cost of this node, for road tracks */
    00338 static int32 NPFRoadPathCost(AyStar *as, AyStarNode *current, OpenListNode *parent)
    00339 {
    00340   TileIndex tile = current->tile;
    00341   int32 cost = 0;
    00342
    00343   /* Determine base length */
    00344   switch (GetTileType(tile)) {
    00345     case MP_TUNNELBRIDGE:
    00346       cost = IsTunnel(tile) ? NPFTunnelCost(current) : NPFBridgeCost(current);
    00347       break;
    00348
    00349     case MP_ROAD:
    00350       cost = NPF_TILE_LENGTH;
    00351       /* Increase the cost for level crossings */
    00352       if (IsLevelCrossing(tile)) cost += _settings_game.pf.npf.npf_crossing_penalty;
    00353       break;
    00354
    00355     case MP_STATION: {
    00356       cost = NPF_TILE_LENGTH;
    00357       const RoadStop *rs = RoadStop::GetByTile(tile, GetRoadStopType(tile));
    00358       if (IsDriveThroughStopTile(tile)) {
    00359         /* Increase the cost for drive-through road stops */
    00360         cost += _settings_game.pf.npf.npf_road_drive_through_penalty;
    00361         DiagDirection dir = TrackdirToExitdir(current->direction);
    00362         if (!RoadStop::IsDriveThroughRoadStopContinuation(tile, tile - TileOffsByDiagDir(dir))) {
    00363           /* When we're the first road stop in a 'queue' of them we increase
    00364            * cost based on the fill percentage of the whole queue. */
    00365           const RoadStop::Entry *entry = rs->GetEntry(dir);
    00366           cost += entry->GetOccupied() * _settings_game.pf.npf.npf_road_dt_occupied_penalty / entry->GetLength();
    00367         }
    00368       } else {
    00369         /* Increase cost for filled road stops */
    00370         cost += _settings_game.pf.npf.npf_road_bay_occupied_penalty * (!rs->IsFreeBay(0) + !rs->IsFreeBay(1)) / 2;
    00371       }
    00372     } break;
    00373
    00374     default:
    00375       break;
    00376   }
    00377
    00378   /* Determine extra costs */
    00379
    00380   /* Check for slope */
    00381   cost += NPFSlopeCost(current);
    00382
    00383   /* Check for turns. Road vehicles only really drive diagonal, turns are
    00384    * represented by non-diagonal tracks */
    00385   if (!IsDiagonalTrackdir(current->direction))
    00386     cost += _settings_game.pf.npf.npf_road_curve_penalty;
    00387
    00388   NPFMarkTile(tile);
    00389   DEBUG(npf, 4, "Calculating G for: (%d, %d). Result: %d", TileX(current->tile), TileY(current->tile), cost);
    00390   return cost;
    00391 }
    00392
    00393
    00394 /* Determine the cost of this node, for railway tracks */
    00395 static int32 NPFRailPathCost(AyStar *as, AyStarNode *current, OpenListNode *parent)
    00396 {
    00397   TileIndex tile = current->tile;
    00398   Trackdir trackdir = current->direction;
    00399   int32 cost = 0;
    00400   /* HACK: We create a OpenListNode manually, so we can call EndNodeCheck */
    00401   OpenListNode new_node;
    00402
    00403   /* Determine base length */
    00404   switch (GetTileType(tile)) {
    00405     case MP_TUNNELBRIDGE:
    00406       cost = IsTunnel(tile) ? NPFTunnelCost(current) : NPFBridgeCost(current);
    00407       break;
    00408
    00409     case MP_RAILWAY:
    00410       cost = _trackdir_length[trackdir]; // Should be different for diagonal tracks
    00411       break;
    00412
    00413     case MP_ROAD: // Railway crossing
    00414       cost = NPF_TILE_LENGTH;
    00415       break;
    00416
    00417     case MP_STATION:
    00418       /* We give a station tile a penalty. Logically we would only want to give
    00419        * station tiles that are not our destination this penalty. This would
    00420        * discourage trains to drive through busy stations. But, we can just
    00421        * give any station tile a penalty, because every possible route will get
    00422        * this penalty exactly once, on its end tile (if it's a station) and it
    00423        * will therefore not make a difference. */
    00424       cost = NPF_TILE_LENGTH + _settings_game.pf.npf.npf_rail_station_penalty;
    00425
    00426       if (IsRailWaypoint(tile)) {
    00427         NPFFindStationOrTileData *fstd = (NPFFindStationOrTileData*)as->user_target;
    00428         if (fstd->v->current_order.IsType(OT_GOTO_WAYPOINT) && GetStationIndex(tile) == fstd->v->current_order.GetDestination()) {
    00429           /* This waypoint is our destination; maybe this isn't an unreserved
    00430            * one, so check that and if so see that as the last signal being
    00431            * red. This way waypoints near stations should work better. */
    00432           const Train *train = Train::From(fstd->v);
    00433           CFollowTrackRail ft(train);
    00434           TileIndex t = tile;
    00435           Trackdir td = trackdir;
    00436           while (ft.Follow(t, td)) {
    00437             assert(t != ft.m_new_tile);
    00438             t = ft.m_new_tile;
    00439             if (KillFirstBit(ft.m_new_td_bits) != TRACKDIR_BIT_NONE) {
    00440               /* We encountered a junction; it's going to be too complex to
    00441                * handle this perfectly, so just bail out. There is no simple
    00442                * free path, so try the other possibilities. */
    00443               td = INVALID_TRACKDIR;
    00444               break;
    00445             }
    00446             td = RemoveFirstTrackdir(&ft.m_new_td_bits);
    00447             /* If this is a safe waiting position we're done searching for it */
    00448             if (IsSafeWaitingPosition(train, t, td, true, _settings_game.pf.forbid_90_deg)) break;
    00449           }
    00450           if (td == INVALID_TRACKDIR ||
    00451               !IsSafeWaitingPosition(train, t, td, true, _settings_game.pf.forbid_90_deg) ||
    00452               !IsWaitingPositionFree(train, t, td, _settings_game.pf.forbid_90_deg)) {
    00453             cost += _settings_game.pf.npf.npf_rail_lastred_penalty;
    00454           }
    00455         }
    00456       }
    00457       break;
    00458
    00459     default:
    00460       break;
    00461   }
    00462
    00463   /* Determine extra costs */
    00464
    00465   /* Check for signals */
    00466   if (IsTileType(tile, MP_RAILWAY)) {
    00467     if (HasSignalOnTrackdir(tile, trackdir)) {
    00468       SignalType sigtype = GetSignalType(tile, TrackdirToTrack(trackdir));
    00469       /* Ordinary track with signals */
    00470       if (GetSignalStateByTrackdir(tile, trackdir) == SIGNAL_STATE_RED) {
    00471         /* Signal facing us is red */
    00472         if (!NPFGetFlag(current, NPF_FLAG_SEEN_SIGNAL)) {
    00473           /* Penalize the first signal we
    00474            * encounter, if it is red */
    00475
    00476           /* Is this a presignal exit or combo? */
    00477           if (!IsPbsSignal(sigtype)) {
    00478             if (sigtype == SIGTYPE_EXIT || sigtype == SIGTYPE_COMBO) {
    00479               /* Penalise exit and combo signals differently (heavier) */
    00480               cost += _settings_game.pf.npf.npf_rail_firstred_exit_penalty;
    00481             } else {
    00482               cost += _settings_game.pf.npf.npf_rail_firstred_penalty;
    00483             }
    00484           }
    00485         }
    00486         /* Record the state of this signal */
    00487         NPFSetFlag(current, NPF_FLAG_LAST_SIGNAL_RED, true);
    00488       } else {
    00489         /* Record the state of this signal */
    00490         NPFSetFlag(current, NPF_FLAG_LAST_SIGNAL_RED, false);
    00491       }
    00492       if (NPFGetFlag(current, NPF_FLAG_SEEN_SIGNAL)) {
    00493         if (NPFGetFlag(current, NPF_FLAG_2ND_SIGNAL)) {
    00494           NPFSetFlag(current, NPF_FLAG_3RD_SIGNAL, true);
    00495         } else {
    00496           NPFSetFlag(current, NPF_FLAG_2ND_SIGNAL, true);
    00497         }
    00498       } else {
    00499         NPFSetFlag(current, NPF_FLAG_SEEN_SIGNAL, true);
    00500       }
    00501       NPFSetFlag(current, NPF_FLAG_LAST_SIGNAL_BLOCK, !IsPbsSignal(sigtype));
    00502     }
    00503
    00504     if (HasPbsSignalOnTrackdir(tile, ReverseTrackdir(trackdir)) && !NPFGetFlag(current, NPF_FLAG_3RD_SIGNAL)) {
    00505       cost += _settings_game.pf.npf.npf_rail_pbs_signal_back_penalty;
    00506     }
    00507   }
    00508
    00509   /* Penalise the tile if it is a target tile and the last signal was
    00510    * red */
    00511   /* HACK: We create a new_node here so we can call EndNodeCheck. Ugly as hell
    00512    * of course... */
    00513   new_node.path.node = *current;
    00514   if (as->EndNodeCheck(as, &new_node) == AYSTAR_FOUND_END_NODE && NPFGetFlag(current, NPF_FLAG_LAST_SIGNAL_RED))
    00515     cost += _settings_game.pf.npf.npf_rail_lastred_penalty;
    00516
    00517   /* Check for slope */
    00518   cost += NPFSlopeCost(current);
    00519
    00520   /* Check for turns */
    00521   if (current->direction != NextTrackdir((Trackdir)parent->path.node.direction))
    00522     cost += _settings_game.pf.npf.npf_rail_curve_penalty;
    00523   /* TODO, with realistic acceleration, also the amount of straight track between
    00524    *      curves should be taken into account, as this affects the speed limit. */
    00525
    00526   /* Check for reverse in depot */
    00527   if (IsRailDepotTile(tile) && as->EndNodeCheck(as, &new_node) != AYSTAR_FOUND_END_NODE) {
    00528     /* Penalise any depot tile that is not the last tile in the path. This
    00529      * _should_ penalise every occurence of reversing in a depot (and only
    00530      * that) */
    00531     cost += _settings_game.pf.npf.npf_rail_depot_reverse_penalty;
    00532   }
    00533
    00534   /* Check for occupied track */
    00535   cost += NPFReservedTrackCost(current);
    00536
    00537   NPFMarkTile(tile);
    00538   DEBUG(npf, 4, "Calculating G for: (%d, %d). Result: %d", TileX(current->tile), TileY(current->tile), cost);
    00539   return cost;
    00540 }
    00541
    00542 /* Will find any depot */
    00543 static int32 NPFFindDepot(AyStar *as, OpenListNode *current)
    00544 {
    00545   /* It's not worth caching the result with NPF_FLAG_IS_TARGET here as below,
    00546    * since checking the cache not that much faster than the actual check */
    00547   return IsDepotTypeTile(current->path.node.tile, (TransportType)as->user_data[NPF_TYPE]) ?
    00548     AYSTAR_FOUND_END_NODE : AYSTAR_DONE;
    00549 }
    00550
    00552 static int32 NPFFindSafeTile(AyStar *as, OpenListNode *current)
    00553 {
    00554   const Train *v = Train::From(((NPFFindStationOrTileData *)as->user_target)->v);
    00555
    00556   return
    00557     IsSafeWaitingPosition(v, current->path.node.tile, current->path.node.direction, true, _settings_game.pf.forbid_90_deg) &&
    00558     IsWaitingPositionFree(v, current->path.node.tile, current->path.node.direction, _settings_game.pf.forbid_90_deg) ?
    00559       AYSTAR_FOUND_END_NODE : AYSTAR_DONE;
    00560 }
    00561
    00562 /* Will find a station identified using the NPFFindStationOrTileData */
    00563 static int32 NPFFindStationOrTile(AyStar *as, OpenListNode *current)
    00564 {
    00565   NPFFindStationOrTileData *fstd = (NPFFindStationOrTileData*)as->user_target;
    00566   AyStarNode *node = &current->path.node;
    00567   TileIndex tile = node->tile;
    00568
    00569   if (fstd->station_index == INVALID_STATION && tile == fstd->dest_coords) return AYSTAR_FOUND_END_NODE;
    00570
    00571   if (IsTileType(tile, MP_STATION) && GetStationIndex(tile) == fstd->station_index) {
    00572     if (fstd->v->type == VEH_TRAIN) return AYSTAR_FOUND_END_NODE;
    00573
    00574     assert(fstd->v->type == VEH_ROAD);
    00575     /* Only if it is a valid station *and* we can stop there */
    00576     if (GetStationType(tile) == fstd->station_type && (fstd->not_articulated || IsDriveThroughStopTile(tile))) return AYSTAR_FOUND_END_NODE;
    00577   }
    00578   return AYSTAR_DONE;
    00579 }
    00580
    00588 static const PathNode *FindSafePosition(PathNode *path, const Train *v)
    00589 {
    00590   /* If there is no signal, reserve the whole path. */
    00591   PathNode *sig = path;
    00592
    00593   for (; path->parent != NULL; path = path->parent) {
    00594     if (IsSafeWaitingPosition(v, path->node.tile, path->node.direction, true, _settings_game.pf.forbid_90_deg)) {
    00595       sig = path;
    00596     }
    00597   }
    00598
    00599   return sig;
    00600 }
    00601
    00605 static void ClearPathReservation(const PathNode *start, const PathNode *end)
    00606 {
    00607   bool first_run = true;
    00608   for (; start != end; start = start->parent) {
    00609     if (IsRailStationTile(start->node.tile) && first_run) {
    00610       SetRailStationPlatformReservation(start->node.tile, TrackdirToExitdir(start->node.direction), false);
    00611     } else {
    00612       UnreserveRailTrack(start->node.tile, TrackdirToTrack(start->node.direction));
    00613     }
    00614     first_run = false;
    00615   }
    00616 }
    00617
    00624 static void NPFSaveTargetData(AyStar *as, OpenListNode *current)
    00625 {
    00626   NPFFoundTargetData *ftd = (NPFFoundTargetData*)as->user_path;
    00627   ftd->best_trackdir = (Trackdir)current->path.node.user_data[NPF_TRACKDIR_CHOICE];
    00628   ftd->best_path_dist = current->g;
    00629   ftd->best_bird_dist = 0;
    00630   ftd->node = current->path.node;
    00631   ftd->res_okay = false;
    00632
    00633   if (as->user_target != NULL && ((NPFFindStationOrTileData*)as->user_target)->reserve_path && as->user_data[NPF_TYPE] == TRANSPORT_RAIL) {
    00634     /* Path reservation is requested. */
    00635     const Train *v = Train::From(((NPFFindStationOrTileData *)as->user_target)->v);
    00636
    00637     const PathNode *target = FindSafePosition(&current->path, v);
    00638     ftd->node = target->node;
    00639
    00640     /* If the target is a station skip to platform end. */
    00641     if (IsRailStationTile(target->node.tile)) {
    00642       DiagDirection dir = TrackdirToExitdir(target->node.direction);
    00643       uint len = Station::GetByTile(target->node.tile)->GetPlatformLength(target->node.tile, dir);
    00644       TileIndex end_tile = TILE_ADD(target->node.tile, (len - 1) * TileOffsByDiagDir(dir));
    00645
    00646       /* Update only end tile, trackdir of a station stays the same. */
    00647       ftd->node.tile = end_tile;
    00648       if (!IsWaitingPositionFree(v, end_tile, target->node.direction, _settings_game.pf.forbid_90_deg)) return;
    00649       SetRailStationPlatformReservation(target->node.tile, dir, true);
    00650       SetRailStationReservation(target->node.tile, false);
    00651     } else {
    00652       if (!IsWaitingPositionFree(v, target->node.tile, target->node.direction, _settings_game.pf.forbid_90_deg)) return;
    00653     }
    00654
    00655     for (const PathNode *cur = target; cur->parent != NULL; cur = cur->parent) {
    00656       if (!TryReserveRailTrack(cur->node.tile, TrackdirToTrack(cur->node.direction))) {
    00657         /* Reservation failed, undo. */
    00658         ClearPathReservation(target, cur);
    00659         return;
    00660       }
    00661     }
    00662
    00663     ftd->res_okay = true;
    00664   }
    00665 }
    00666
    00676 static bool CanEnterTileOwnerCheck(Owner owner, TileIndex tile, DiagDirection enterdir)
    00677 {
    00678   switch (GetTileType(tile)) {
    00679     case MP_RAILWAY:
    00680       return IsInfraTileUsageAllowed(tile, owner, VEH_TRAIN); // Rail tile (also rail depot)
    00681
    00682     case MP_ROAD:
    00683       /* rail-road crossing : are we looking at the railway part? */
    00684       if (IsLevelCrossing(tile) &&
    00685           DiagDirToAxis(enterdir) != GetCrossingRoadAxis(tile)) {
    00686         return IsInfraTileUsageAllowed(tile, owner, VEH_TRAIN); // Railway needs owner check, while the street is public
    00687       } else if (IsRoadDepot(tile)) { // Road depot tile
    00688         return IsInfraTileUsageAllowed(tile, owner, VEH_ROAD);
    00689       }
    00690       break;
    00691
    00692     case MP_STATION:
    00693       if (HasStationRail(tile)) { // Rail station tile/waypoint
    00694         return IsInfraTileUsageAllowed(tile, owner, VEH_TRAIN);
    00695       } else if (IsStandardRoadStopTile(tile)) { // Road station tile (but not drive-through stops)
    00696         return IsInfraTileUsageAllowed(tile, owner, VEH_ROAD);
    00697       }
    00698       break;
    00699
    00700     case MP_TUNNELBRIDGE:
    00701       if (GetTunnelBridgeTransportType(tile) == TRANSPORT_RAIL) {
    00702         return IsInfraTileUsageAllowed(tile, owner, VEH_TRAIN);
    00703       }
    00704       break;
    00705
    00706     default:
    00707       break;
    00708   }
    00709
    00710   return true; // no need to check
    00711 }
    00712
    00713
    00717 static DiagDirection GetDepotDirection(TileIndex tile, TransportType type)
    00718 {
    00719   assert(IsDepotTypeTile(tile, type));
    00720
    00721   switch (type) {
    00722     case TRANSPORT_RAIL:  return GetRailDepotDirection(tile);
    00723     case TRANSPORT_ROAD:  return GetRoadDepotDirection(tile);
    00724     case TRANSPORT_WATER: return GetShipDepotDirection(tile);
    00725     default: return INVALID_DIAGDIR; // Not reached
    00726   }
    00727 }
    00728
    00730 static DiagDirection GetSingleTramBit(TileIndex tile)
    00731 {
    00732   if (IsNormalRoadTile(tile)) {
    00733     RoadBits rb = GetRoadBits(tile, ROADTYPE_TRAM);
    00734     switch (rb) {
    00735       case ROAD_NW: return DIAGDIR_NW;
    00736       case ROAD_SW: return DIAGDIR_SW;
    00737       case ROAD_SE: return DIAGDIR_SE;
    00738       case ROAD_NE: return DIAGDIR_NE;
    00739       default: break;
    00740     }
    00741   }
    00742   return INVALID_DIAGDIR;
    00743 }
    00744
    00755 static DiagDirection GetTileSingleEntry(TileIndex tile, TransportType type, uint subtype)
    00756 {
    00757   if (type != TRANSPORT_WATER && IsDepotTypeTile(tile, type)) return GetDepotDirection(tile, type);
    00758
    00759   if (type == TRANSPORT_ROAD) {
    00760     if (IsStandardRoadStopTile(tile)) return GetRoadStopDir(tile);
    00761     if (HasBit(subtype, ROADTYPE_TRAM)) return GetSingleTramBit(tile);
    00762   }
    00763
    00764   return INVALID_DIAGDIR;
    00765 }
    00766
    00776 static inline bool ForceReverse(TileIndex tile, DiagDirection dir, TransportType type, uint subtype)
    00777 {
    00778   DiagDirection single_entry = GetTileSingleEntry(tile, type, subtype);
    00779   return single_entry != INVALID_DIAGDIR && single_entry != dir;
    00780 }
    00781
    00793 static bool CanEnterTile(TileIndex tile, DiagDirection dir, TransportType type, uint subtype, RailTypes railtypes, Owner owner)
    00794 {
    00795   /* Check tunnel entries and bridge ramps */
    00796   if (IsTileType(tile, MP_TUNNELBRIDGE) && GetTunnelBridgeDirection(tile) != dir) return false;
    00797
    00798   /* Test ownership */
    00799   if (!CanEnterTileOwnerCheck(owner, tile, dir)) return false;
    00800
    00801   /* check correct rail type (mono, maglev, etc) */
    00802   if (type == TRANSPORT_RAIL) {
    00803     RailType rail_type = GetTileRailType(tile);
    00804     if (!HasBit(railtypes, rail_type)) return false;
    00805   }
    00806
    00807   /* Depots, standard roadstops and single tram bits can only be entered from one direction */
    00808   DiagDirection single_entry = GetTileSingleEntry(tile, type, subtype);
    00809   if (single_entry != INVALID_DIAGDIR && single_entry != ReverseDiagDir(dir)) return false;
    00810
    00811   return true;
    00812 }
    00813
    00825 static TrackdirBits GetDriveableTrackdirBits(TileIndex dst_tile, Trackdir src_trackdir, TransportType type, uint subtype)
    00826 {
    00827   TrackdirBits trackdirbits = TrackStatusToTrackdirBits(GetTileTrackStatus(dst_tile, type, subtype));
    00828
    00829   if (trackdirbits == 0 && type == TRANSPORT_ROAD && HasBit(subtype, ROADTYPE_TRAM)) {
    00830     /* GetTileTrackStatus() returns 0 for single tram bits.
    00831      * As we cannot change it there (easily) without breaking something, change it here */
    00832     switch (GetSingleTramBit(dst_tile)) {
    00833       case DIAGDIR_NE:
    00834       case DIAGDIR_SW:
    00835         trackdirbits = TRACKDIR_BIT_X_NE | TRACKDIR_BIT_X_SW;
    00836         break;
    00837
    00838       case DIAGDIR_NW:
    00839       case DIAGDIR_SE:
    00840         trackdirbits = TRACKDIR_BIT_Y_NW | TRACKDIR_BIT_Y_SE;
    00841         break;
    00842
    00843       default: break;
    00844     }
    00845   }
    00846
    00847   DEBUG(npf, 4, "Next node: (%d, %d) [%d], possible trackdirs: 0x%X", TileX(dst_tile), TileY(dst_tile), dst_tile, trackdirbits);
    00848
    00849   /* Select only trackdirs we can reach from our current trackdir */
    00850   trackdirbits &= TrackdirReachesTrackdirs(src_trackdir);
    00851
    00852   /* Filter out trackdirs that would make 90 deg turns for trains */
    00853   if (_settings_game.pf.forbid_90_deg && (type == TRANSPORT_RAIL || type == TRANSPORT_WATER)) trackdirbits &= ~TrackdirCrossesTrackdirs(src_trackdir);
    00854
    00855   DEBUG(npf, 6, "After filtering: (%d, %d), possible trackdirs: 0x%X", TileX(dst_tile), TileY(dst_tile), trackdirbits);
    00856
    00857   return trackdirbits;
    00858 }
    00859
    00860
    00861 /* Will just follow the results of GetTileTrackStatus concerning where we can
    00862  * go and where not. Uses AyStar.user_data[NPF_TYPE] as the transport type and
    00863  * an argument to GetTileTrackStatus. Will skip tunnels, meaning that the
    00864  * entry and exit are neighbours. Will fill
    00865  * AyStarNode.user_data[NPF_TRACKDIR_CHOICE] with an appropriate value, and
    00866  * copy AyStarNode.user_data[NPF_NODE_FLAGS] from the parent */
    00867 static void NPFFollowTrack(AyStar *aystar, OpenListNode *current)
    00868 {
    00869   /* We leave src_tile on track src_trackdir in direction src_exitdir */
    00870   Trackdir src_trackdir = current->path.node.direction;
    00871   TileIndex src_tile = current->path.node.tile;
    00872   DiagDirection src_exitdir = TrackdirToExitdir(src_trackdir);
    00873
    00874   /* Is src_tile valid, and can be used?
    00875    * When choosing track on a junction src_tile is the tile neighboured to the junction wrt. exitdir.
    00876    * 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. */
    00877   bool ignore_src_tile = (current->path.parent == NULL && NPFGetFlag(&current->path.node, NPF_FLAG_IGNORE_START_TILE));
    00878
    00879   /* Information about the vehicle: TransportType (road/rail/water) and SubType (compatible rail/road types) */
    00880   TransportType type = (TransportType)aystar->user_data[NPF_TYPE];
    00881   uint subtype = aystar->user_data[NPF_SUB_TYPE];
    00882
    00883   /* Initialize to 0, so we can jump out (return) somewhere an have no neighbours */
    00884   aystar->num_neighbours = 0;
    00885   DEBUG(npf, 4, "Expanding: (%d, %d, %d) [%d]", TileX(src_tile), TileY(src_tile), src_trackdir, src_tile);
    00886
    00887   /* We want to determine the tile we arrive, and which choices we have there */
    00888   TileIndex dst_tile;
    00889   TrackdirBits trackdirbits;
    00890
    00891   /* Find dest tile */
    00892   if (ignore_src_tile) {
    00893     /* Do not perform any checks that involve src_tile */
    00894     dst_tile = src_tile + TileOffsByDiagDir(src_exitdir);
    00895     trackdirbits = GetDriveableTrackdirBits(dst_tile, src_trackdir, type, subtype);
    00896   } else if (IsTileType(src_tile, MP_TUNNELBRIDGE) && GetTunnelBridgeDirection(src_tile) == src_exitdir) {
    00897     /* We drive through the wormhole and arrive on the other side */
    00898     dst_tile = GetOtherTunnelBridgeEnd(src_tile);
    00899     trackdirbits = TrackdirToTrackdirBits(src_trackdir);
    00900   } else if (ForceReverse(src_tile, src_exitdir, type, subtype)) {
    00901     /* We can only reverse on this tile */
    00902     dst_tile = src_tile;
    00903     src_trackdir = ReverseTrackdir(src_trackdir);
    00904     trackdirbits = TrackdirToTrackdirBits(src_trackdir);
    00905   } else {
    00906     /* We leave src_tile in src_exitdir and reach dst_tile */
    00907     dst_tile = AddTileIndexDiffCWrap(src_tile, TileIndexDiffCByDiagDir(src_exitdir));
    00908
    00909     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;
    00910
    00911     if (dst_tile == INVALID_TILE) {
    00912       /* We cannot enter the next tile. Road vehicles can reverse, others reach dead end */
    00913       if (type != TRANSPORT_ROAD || HasBit(subtype, ROADTYPE_TRAM)) return;
    00914
    00915       dst_tile = src_tile;
    00916       src_trackdir = ReverseTrackdir(src_trackdir);
    00917     }
    00918
    00919     trackdirbits = GetDriveableTrackdirBits(dst_tile, src_trackdir, type, subtype);
    00920
    00921     if (trackdirbits == 0) {
    00922       /* We cannot enter the next tile. Road vehicles can reverse, others reach dead end */
    00923       if (type != TRANSPORT_ROAD || HasBit(subtype, ROADTYPE_TRAM)) return;
    00924
    00925       dst_tile = src_tile;
    00926       src_trackdir = ReverseTrackdir(src_trackdir);
    00927
    00928       trackdirbits = GetDriveableTrackdirBits(dst_tile, src_trackdir, type, subtype);
    00929     }
    00930   }
    00931
    00932   if (NPFGetFlag(&current->path.node, NPF_FLAG_IGNORE_RESERVED)) {
    00933     /* Mask out any reserved tracks. */
    00934     TrackBits reserved = GetReservedTrackbits(dst_tile);
    00935     trackdirbits &= ~TrackBitsToTrackdirBits(reserved);
    00936
    00937     uint bits = TrackdirBitsToTrackBits(trackdirbits);
    00938     int i;
    00939     FOR_EACH_SET_BIT(i, bits) {
    00940       if (TracksOverlap(reserved | TrackToTrackBits((Track)i))) trackdirbits &= ~TrackToTrackdirBits((Track)i);
    00941     }
    00942   }
    00943
    00944   /* Enumerate possible track */
    00945   uint i = 0;
    00946   while (trackdirbits != 0) {
    00947     Trackdir dst_trackdir = RemoveFirstTrackdir(&trackdirbits);
    00948     DEBUG(npf, 5, "Expanded into trackdir: %d, remaining trackdirs: 0x%X", dst_trackdir, trackdirbits);
    00949
    00950     /* Tile with signals? */
    00951     if (IsTileType(dst_tile, MP_RAILWAY) && GetRailTileType(dst_tile) == RAIL_TILE_SIGNALS) {
    00952       if (HasSignalOnTrackdir(dst_tile, ReverseTrackdir(dst_trackdir)) && !HasSignalOnTrackdir(dst_tile, dst_trackdir) && IsOnewaySignal(dst_tile, TrackdirToTrack(dst_trackdir)))
    00953         /* If there's a one-way signal not pointing towards us, stop going in this direction. */
    00954         break;
    00955     }
    00956     {
    00957       /* We've found ourselves a neighbour :-) */
    00958       AyStarNode *neighbour = &aystar->neighbours[i];
    00959       neighbour->tile = dst_tile;
    00960       neighbour->direction = dst_trackdir;
    00961       /* Save user data */
    00962       neighbour->user_data[NPF_NODE_FLAGS] = current->path.node.user_data[NPF_NODE_FLAGS];
    00963       NPFFillTrackdirChoice(neighbour, current);
    00964     }
    00965     i++;
    00966   }
    00967   aystar->num_neighbours = i;
    00968 }
    00969
    00970 /*
    00971  * Plan a route to the specified target (which is checked by target_proc),
    00972  * from start1 and if not NULL, from start2 as well. The type of transport we
    00973  * are checking is in type. reverse_penalty is applied to all routes that
    00974  * originate from the second start node.
    00975  * When we are looking for one specific target (optionally multiple tiles), we
    00976  * should use a good heuristic to perform aystar search. When we search for
    00977  * multiple targets that are spread around, we should perform a breadth first
    00978  * search by specifiying CalcZero as our heuristic.
    00979  */
    00980 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)
    00981 {
    00982   int r;
    00983   NPFFoundTargetData result;
    00984
    00985   /* Initialize procs */
    00986   _npf_aystar.CalculateH = heuristic_proc;
    00987   _npf_aystar.EndNodeCheck = target_proc;
    00988   _npf_aystar.FoundEndNode = NPFSaveTargetData;
    00989   _npf_aystar.GetNeighbours = NPFFollowTrack;
    00990   switch (type) {
    00991     default: NOT_REACHED();
    00992     case TRANSPORT_RAIL:  _npf_aystar.CalculateG = NPFRailPathCost;  break;
    00993     case TRANSPORT_ROAD:  _npf_aystar.CalculateG = NPFRoadPathCost;  break;
    00994     case TRANSPORT_WATER: _npf_aystar.CalculateG = NPFWaterPathCost; break;
    00995   }
    00996
    00997   /* Initialize Start Node(s) */
    00998   start1->user_data[NPF_TRACKDIR_CHOICE] = INVALID_TRACKDIR;
    00999   start1->user_data[NPF_NODE_FLAGS] = 0;
    01000   NPFSetFlag(start1, NPF_FLAG_IGNORE_START_TILE, ignore_start_tile1);
    01001   _npf_aystar.addstart(&_npf_aystar, start1, 0);
    01002   if (start2) {
    01003     start2->user_data[NPF_TRACKDIR_CHOICE] = INVALID_TRACKDIR;
    01004     start2->user_data[NPF_NODE_FLAGS] = 0;
    01005     NPFSetFlag(start2, NPF_FLAG_IGNORE_START_TILE, ignore_start_tile2);
    01006     NPFSetFlag(start2, NPF_FLAG_REVERSE, true);
    01007     _npf_aystar.addstart(&_npf_aystar, start2, reverse_penalty);
    01008   }
    01009
    01010   /* Initialize result */
    01011   result.best_bird_dist = UINT_MAX;
    01012   result.best_path_dist = UINT_MAX;
    01013   result.best_trackdir  = INVALID_TRACKDIR;
    01014   result.node.tile      = INVALID_TILE;
    01015   result.res_okay       = false;
    01016   _npf_aystar.user_path = &result;
    01017
    01018   /* Initialize target */
    01019   _npf_aystar.user_target = target;
    01020
    01021   /* Initialize user_data */
    01022   _npf_aystar.user_data[NPF_TYPE] = type;
    01023   _npf_aystar.user_data[NPF_SUB_TYPE] = sub_type;
    01024   _npf_aystar.user_data[NPF_OWNER] = owner;
    01025   _npf_aystar.user_data[NPF_RAILTYPES] = railtypes;
    01026
    01027   /* GO! */
    01028   r = AyStarMain_Main(&_npf_aystar);
    01029   assert(r != AYSTAR_STILL_BUSY);
    01030
    01031   if (result.best_bird_dist != 0) {
    01032     if (target != NULL) {
    01033       DEBUG(npf, 1, "Could not find route to tile 0x%X from 0x%X.", target->dest_coords, start1->tile);
    01034     } else {
    01035       /* Assumption: target == NULL, so we are looking for a depot */
    01036       DEBUG(npf, 1, "Could not find route to a depot from tile 0x%X.", start1->tile);
    01037     }
    01038
    01039   }
    01040   return result;
    01041 }
    01042
    01043 /* Will search as below, but with two start nodes, the second being the
    01044  * reverse. Look at the NPF_FLAG_REVERSE flag in the result node to see which
    01045  * direction was taken (NPFGetFlag(result.node, NPF_FLAG_REVERSE)) */
    01046 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)
    01047 {
    01048   AyStarNode start1;
    01049   AyStarNode start2;
    01050
    01051   start1.tile = tile1;
    01052   start2.tile = tile2;
    01053   /* We set this in case the target is also the start tile, we will just
    01054    * return a not found then */
    01055   start1.user_data[NPF_TRACKDIR_CHOICE] = INVALID_TRACKDIR;
    01056   start1.direction = trackdir1;
    01057   start2.direction = trackdir2;
    01058   start2.user_data[NPF_TRACKDIR_CHOICE] = INVALID_TRACKDIR;
    01059
    01060   return NPFRouteInternal(&start1, ignore_start_tile1, (IsValidTile(tile2) ? &start2 : NULL), ignore_start_tile2, target, NPFFindStationOrTile, NPFCalcStationOrTileHeuristic, type, sub_type, owner, railtypes, 0);
    01061 }
    01062
    01063 /* Will search from the given tile and direction, for a route to the given
    01064  * station for the given transport type. See the declaration of
    01065  * NPFFoundTargetData above for the meaning of the result. */
    01066 static NPFFoundTargetData NPFRouteToStationOrTile(TileIndex tile, Trackdir trackdir, bool ignore_start_tile, NPFFindStationOrTileData *target, TransportType type, uint sub_type, Owner owner, RailTypes railtypes)
    01067 {
    01068   return NPFRouteToStationOrTileTwoWay(tile, trackdir, ignore_start_tile, INVALID_TILE, INVALID_TRACKDIR, false, target, type, sub_type, owner, railtypes);
    01069 }
    01070
    01071 /* Search using breadth first. Good for little track choice and inaccurate
    01072  * heuristic, such as railway/road with two start nodes, the second being the reverse. Call
    01073  * NPFGetFlag(result.node, NPF_FLAG_REVERSE) to see from which node the path
    01074  * orginated. All pathfs from the second node will have the given
    01075  * reverse_penalty applied (NPF_TILE_LENGTH is the equivalent of one full
    01076  * tile).
    01077  */
    01078 static NPFFoundTargetData NPFRouteToDepotBreadthFirstTwoWay(TileIndex tile1, Trackdir trackdir1, bool ignore_start_tile1, TileIndex tile2, Trackdir trackdir2, bool ignore_start_tile2, TransportType type, uint sub_type, Owner owner, RailTypes railtypes, uint reverse_penalty)
    01079 {
    01080   AyStarNode start1;
    01081   AyStarNode start2;
    01082
    01083   start1.tile = tile1;
    01084   start2.tile = tile2;
    01085   /* We set this in case the target is also the start tile, we will just
    01086    * return a not found then */
    01087   start1.user_data[NPF_TRACKDIR_CHOICE] = INVALID_TRACKDIR;
    01088   start1.direction = trackdir1;
    01089   start2.direction = trackdir2;
    01090   start2.user_data[NPF_TRACKDIR_CHOICE] = INVALID_TRACKDIR;
    01091
    01092   /* perform a breadth first search. Target is NULL,
    01093    * since we are just looking for any depot...*/
    01094   return NPFRouteInternal(&start1, ignore_start_tile1, (IsValidTile(tile2) ? &start2 : NULL), ignore_start_tile2, NULL, NPFFindDepot, NPFCalcZero, type, sub_type, owner, railtypes, reverse_penalty);
    01095 }
    01096
    01097 void InitializeNPF()
    01098 {
    01099   static bool first_init = true;
    01100   if (first_init) {
    01101     first_init = false;
    01102     init_AyStar(&_npf_aystar, NPFHash, NPF_HASH_SIZE);
    01103   } else {
    01104     AyStarMain_Clear(&_npf_aystar);
    01105   }
    01106   _npf_aystar.loops_per_tick = 0;
    01107   _npf_aystar.max_path_cost = 0;
    01108   //_npf_aystar.max_search_nodes = 0;
    01109   /* We will limit the number of nodes for now, until we have a better
    01110    * solution to really fix performance */
    01111   _npf_aystar.max_search_nodes = _settings_game.pf.npf.npf_max_search_nodes;
    01112 }
    01113
    01114 static void NPFFillWithOrderData(NPFFindStationOrTileData *fstd, const Vehicle *v, bool reserve_path = false)
    01115 {
    01116   /* Ships don't really reach their stations, but the tile in front. So don't
    01117    * save the station id for ships. For roadvehs we don't store it either,
    01118    * because multistop depends on vehicles actually reaching the exact
    01119    * dest_tile, not just any stop of that station.
    01120    * So only for train orders to stations we fill fstd->station_index, for all
    01121    * others only dest_coords */
    01122   if (v->type != VEH_SHIP && (v->current_order.IsType(OT_GOTO_STATION) || v->current_order.IsType(OT_GOTO_WAYPOINT))) {
    01123     assert(v->type == VEH_TRAIN || v->type == VEH_ROAD);
    01124     fstd->station_index = v->current_order.GetDestination();
    01125     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);
    01126     fstd->not_articulated = v->type == VEH_ROAD && !RoadVehicle::From(v)->HasArticulatedPart();
    01127     /* Let's take the closest tile of the station as our target for vehicles */
    01128     fstd->dest_coords = CalcClosestStationTile(fstd->station_index, v->tile, fstd->station_type);
    01129   } else {
    01130     fstd->dest_coords = v->dest_tile;
    01131     fstd->station_index = INVALID_STATION;
    01132   }
    01133   fstd->reserve_path = reserve_path;
    01134   fstd->v = v;
    01135 }
    01136
    01137 /*** Road vehicles ***/
    01138
    01139 FindDepotData NPFRoadVehicleFindNearestDepot(const RoadVehicle *v, int max_penalty)
    01140 {
    01141   Trackdir trackdir = v->GetVehicleTrackdir();
    01142
    01143   NPFFoundTargetData ftd = NPFRouteToDepotBreadthFirstTwoWay(v->tile, trackdir, false, v->tile, ReverseTrackdir(trackdir), false, TRANSPORT_ROAD, v->compatible_roadtypes, v->owner, INVALID_RAILTYPES, 0);
    01144
    01145   if (ftd.best_bird_dist != 0) return FindDepotData();
    01146
    01147   /* Found target */
    01148   /* Our caller expects a number of tiles, so we just approximate that
    01149    * number by this. It might not be completely what we want, but it will
    01150    * work for now :-) We can possibly change this when the old pathfinder
    01151    * is removed. */
    01152   return FindDepotData(ftd.node.tile, ftd.best_path_dist);
    01153 }
    01154
    01155 Trackdir NPFRoadVehicleChooseTrack(const RoadVehicle *v, TileIndex tile, DiagDirection enterdir, TrackdirBits trackdirs)
    01156 {
    01157   NPFFindStationOrTileData fstd;
    01158
    01159   NPFFillWithOrderData(&fstd, v);
    01160   Trackdir trackdir = DiagDirToDiagTrackdir(enterdir);
    01161
    01162   NPFFoundTargetData ftd = NPFRouteToStationOrTile(tile - TileOffsByDiagDir(enterdir), trackdir, true, &fstd, TRANSPORT_ROAD, v->compatible_roadtypes, v->owner, INVALID_RAILTYPES);
    01163   if (ftd.best_trackdir == INVALID_TRACKDIR) {
    01164     /* We are already at our target. Just do something
    01165      * @todo: maybe display error?
    01166      * @todo: go straight ahead if possible? */
    01167     return (Trackdir)FindFirstBit2x64(trackdirs);
    01168   }
    01169
    01170   /* If ftd.best_bird_dist is 0, we found our target and ftd.best_trackdir contains
    01171    * the direction we need to take to get there, if ftd.best_bird_dist is not 0,
    01172    * we did not find our target, but ftd.best_trackdir contains the direction leading
    01173    * to the tile closest to our target. */
    01174   return ftd.best_trackdir;
    01175 }
    01176
    01177 /*** Ships ***/
    01178
    01179 Track NPFShipChooseTrack(const Ship *v, TileIndex tile, DiagDirection enterdir, TrackBits tracks)
    01180 {
    01181   NPFFindStationOrTileData fstd;
    01182   Trackdir trackdir = v->GetVehicleTrackdir();
    01183   assert(trackdir != INVALID_TRACKDIR); // Check that we are not in a depot
    01184
    01185   NPFFillWithOrderData(&fstd, v);
    01186
    01187   NPFFoundTargetData ftd = NPFRouteToStationOrTile(tile - TileOffsByDiagDir(enterdir), trackdir, true, &fstd, TRANSPORT_WATER, 0, v->owner, INVALID_RAILTYPES);
    01188
    01189   /* If ftd.best_bird_dist is 0, we found our target and ftd.best_trackdir contains
    01190    * the direction we need to take to get there, if ftd.best_bird_dist is not 0,
    01191    * we did not find our target, but ftd.best_trackdir contains the direction leading
    01192    * to the tile closest to our target. */
    01193   if (ftd.best_trackdir == 0xff) return INVALID_TRACK;
    01194   return TrackdirToTrack(ftd.best_trackdir);
    01195 }
    01196
    01197 /*** Trains ***/
    01198
    01199 FindDepotData NPFTrainFindNearestDepot(const Train *v, int max_penalty)
    01200 {
    01201   const Train *last = v->Last();
    01202   Trackdir trackdir = v->GetVehicleTrackdir();
    01203   Trackdir trackdir_rev = ReverseTrackdir(last->GetVehicleTrackdir());
    01204
    01205   assert(trackdir != INVALID_TRACKDIR);
    01206   NPFFoundTargetData ftd = NPFRouteToDepotBreadthFirstTwoWay(v->tile, trackdir, false, last->tile, trackdir_rev, false, TRANSPORT_RAIL, 0, v->owner, v->compatible_railtypes, NPF_INFINITE_PENALTY);
    01207   if (ftd.best_bird_dist != 0) return FindDepotData();
    01208
    01209   /* Found target */
    01210   /* Our caller expects a number of tiles, so we just approximate that
    01211    * number by this. It might not be completely what we want, but it will
    01212    * work for now :-) We can possibly change this when the old pathfinder
    01213    * is removed. */
    01214   return FindDepotData(ftd.node.tile, ftd.best_path_dist, NPFGetFlag(&ftd.node, NPF_FLAG_REVERSE));
    01215 }
    01216
    01217 bool NPFTrainFindNearestSafeTile(const Train *v, TileIndex tile, Trackdir trackdir, bool override_railtype)
    01218 {
    01219   assert(v->type == VEH_TRAIN);
    01220
    01221   NPFFindStationOrTileData fstd;
    01222   fstd.v = v;
    01223   fstd.reserve_path = true;
    01224
    01225   AyStarNode start1;
    01226   start1.tile = tile;
    01227   /* We set this in case the target is also the start tile, we will just
    01228    * return a not found then */
    01229   start1.user_data[NPF_TRACKDIR_CHOICE] = INVALID_TRACKDIR;
    01230   start1.direction = trackdir;
    01231   NPFSetFlag(&start1, NPF_FLAG_IGNORE_RESERVED, true);
    01232
    01233   RailTypes railtypes = v->compatible_railtypes;
    01234   if (override_railtype) railtypes |= GetRailTypeInfo(v->railtype)->compatible_railtypes;
    01235
    01236   /* perform a breadth first search. Target is NULL,
    01237    * since we are just looking for any safe tile...*/
    01238   return NPFRouteInternal(&start1, true, NULL, false, &fstd, NPFFindSafeTile, NPFCalcZero, TRANSPORT_RAIL, 0, v->owner, railtypes, 0).res_okay;
    01239 }
    01240
    01241 bool NPFTrainCheckReverse(const Train *v)
    01242 {
    01243   NPFFindStationOrTileData fstd;
    01244   NPFFoundTargetData ftd;
    01245   const Train *last = v->Last();
    01246
    01247   NPFFillWithOrderData(&fstd, v);
    01248
    01249   Trackdir trackdir = v->GetVehicleTrackdir();
    01250   Trackdir trackdir_rev = ReverseTrackdir(last->GetVehicleTrackdir());
    01251   assert(trackdir != INVALID_TRACKDIR);
    01252   assert(trackdir_rev != INVALID_TRACKDIR);
    01253
    01254   ftd = NPFRouteToStationOrTileTwoWay(v->tile, trackdir, false, last->tile, trackdir_rev, false, &fstd, TRANSPORT_RAIL, 0, v->owner, v->compatible_railtypes);
    01255   /* If we didn't find anything, just keep on going straight ahead, otherwise take the reverse flag */
    01256   return ftd.best_bird_dist != 0 && NPFGetFlag(&ftd.node, NPF_FLAG_REVERSE);
    01257 }
    01258
    01259 Track NPFTrainChooseTrack(const Train *v, TileIndex tile, DiagDirection enterdir, TrackBits tracks, bool *path_not_found, bool reserve_track, struct PBSTileInfo *target)
    01260 {
    01261   NPFFindStationOrTileData fstd;
    01262   NPFFillWithOrderData(&fstd, v, reserve_track);
    01263
    01264   PBSTileInfo origin = FollowTrainReservation(v);
    01265   assert(IsValidTrackdir(origin.trackdir));
    01266
    01267   NPFFoundTargetData ftd = NPFRouteToStationOrTile(origin.tile, origin.trackdir, true, &fstd, TRANSPORT_RAIL, 0, v->owner, v->compatible_railtypes);
    01268
    01269   if (target != NULL) {
    01270     target->tile = ftd.node.tile;
    01271     target->trackdir = (Trackdir)ftd.node.direction;
    01272     target->okay = ftd.res_okay;
    01273   }
    01274
    01275   if (ftd.best_trackdir == INVALID_TRACKDIR) {
    01276     /* We are already at our target. Just do something
    01277      * @todo maybe display error?
    01278      * @todo: go straight ahead if possible? */
    01279     if (path_not_found) *path_not_found = false;
    01280     return FindFirstTrack(tracks);
    01281   }
    01282
    01283   /* If ftd.best_bird_dist is 0, we found our target and ftd.best_trackdir contains
    01284    * the direction we need to take to get there, if ftd.best_bird_dist is not 0,
    01285    * we did not find our target, but ftd.best_trackdir contains the direction leading
    01286    * to the tile closest to our target. */
    01287   if (path_not_found != NULL) *path_not_found = (ftd.best_bird_dist != 0);
    01288   /* Discard enterdir information, making it a normal track */
    01289   return TrackdirToTrack(ftd.best_trackdir);
    01290 }