# npf.cpp

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    00001 /* $Id: npf.cpp 12199 2008-02-20 17:49:50Z frosch $ */
    00002
    00005 #include "stdafx.h"
    00006 #include "openttd.h"
    00007 #include "npf.h"
    00008 #include "bridge_map.h"
    00009 #include "debug.h"
    00010 #include "tile_cmd.h"
    00011 #include "bridge.h"
    00012 #include "landscape.h"
    00013 #include "aystar.h"
    00014 #include "pathfind.h"
    00015 #include "station.h"
    00016 #include "station_map.h"
    00017 #include "depot.h"
    00018 #include "tunnel_map.h"
    00019 #include "network/network.h"
    00020 #include "water_map.h"
    00021 #include "tunnelbridge_map.h"
    00022 #include "functions.h"
    00023 #include "vehicle_base.h"
    00024 #include "settings_type.h"
    00025 #include "tunnelbridge.h"
    00026
    00027 static AyStar _npf_aystar;
    00028
    00029 /* The cost of each trackdir. A diagonal piece is the full NPF_TILE_LENGTH,
    00030  * the shorter piece is sqrt(2)/2*NPF_TILE_LENGTH =~ 0.7071
    00031  */
    00032 #define NPF_STRAIGHT_LENGTH (uint)(NPF_TILE_LENGTH * STRAIGHT_TRACK_LENGTH)
    00033 static const uint _trackdir_length[TRACKDIR_END] = {
    00034   NPF_TILE_LENGTH, NPF_TILE_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH,
    00035   0, 0,
    00036   NPF_TILE_LENGTH, NPF_TILE_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH
    00037 };
    00038
    00045 static uint NPFDistanceTrack(TileIndex t0, TileIndex t1)
    00046 {
    00047   const uint dx = Delta(TileX(t0), TileX(t1));
    00048   const uint dy = Delta(TileY(t0), TileY(t1));
    00049
    00050   const uint straightTracks = 2 * min(dx, dy); /* The number of straight (not full length) tracks */
    00051   /* OPTIMISATION:
    00052    * Original: diagTracks = max(dx, dy) - min(dx,dy);
    00053    * Proof:
    00054    * (dx+dy) - straightTracks  == (min + max) - straightTracks = min + max - 2 * min = max - min */
    00055   const uint diagTracks = dx + dy - straightTracks; /* The number of diagonal (full tile length) tracks. */
    00056
    00057   /* Don't factor out NPF_TILE_LENGTH below, this will round values and lose
    00058    * precision */
    00059   return diagTracks * NPF_TILE_LENGTH + straightTracks * NPF_TILE_LENGTH * STRAIGHT_TRACK_LENGTH;
    00060 }
    00061
    00062
    00063 #if 0
    00064 static uint NTPHash(uint key1, uint key2)
    00065 {
    00066   /* This function uses the old hash, which is fixed on 10 bits (1024 buckets) */
    00067   return PATHFIND_HASH_TILE(key1);
    00068 }
    00069 #endif
    00070
    00078 static uint NPFHash(uint key1, uint key2)
    00079 {
    00080   /* TODO: think of a better hash? */
    00081   uint part1 = TileX(key1) & NPF_HASH_HALFMASK;
    00082   uint part2 = TileY(key1) & NPF_HASH_HALFMASK;
    00083
    00084   assert(IsValidTrackdir((Trackdir)key2));
    00085   assert(IsValidTile(key1));
    00086   return ((part1 << NPF_HASH_HALFBITS | part2) + (NPF_HASH_SIZE * key2 / TRACKDIR_END)) % NPF_HASH_SIZE;
    00087 }
    00088
    00089 static int32 NPFCalcZero(AyStar* as, AyStarNode* current, OpenListNode* parent)
    00090 {
    00091   return 0;
    00092 }
    00093
    00094 /* Calcs the tile of given station that is closest to a given tile
    00095  * for this we assume the station is a rectangle,
    00096  * as defined by its top tile (st->train_tile) and its width/height (st->trainst_w, st->trainst_h)
    00097  */
    00098 static TileIndex CalcClosestStationTile(StationID station, TileIndex tile)
    00099 {
    00100   const Station* st = GetStation(station);
    00101
    00102   uint minx = TileX(st->train_tile);  // topmost corner of station
    00103   uint miny = TileY(st->train_tile);
    00104   uint maxx = minx + st->trainst_w - 1; // lowermost corner of station
    00105   uint maxy = miny + st->trainst_h - 1;
    00106   uint x;
    00107   uint y;
    00108
    00109   /* we are going the aim for the x coordinate of the closest corner
    00110    * but if we are between those coordinates, we will aim for our own x coordinate */
    00111   x = Clamp(TileX(tile), minx, maxx);
    00112
    00113   /* same for y coordinate, see above comment */
    00114   y = Clamp(TileY(tile), miny, maxy);
    00115
    00116   /* return the tile of our target coordinates */
    00117   return TileXY(x, y);
    00118 }
    00119
    00120 /* Calcs the heuristic to the target station or tile. For train stations, it
    00121  * takes into account the direction of approach.
    00122  */
    00123 static int32 NPFCalcStationOrTileHeuristic(AyStar* as, AyStarNode* current, OpenListNode* parent)
    00124 {
    00125   NPFFindStationOrTileData* fstd = (NPFFindStationOrTileData*)as->user_target;
    00126   NPFFoundTargetData* ftd = (NPFFoundTargetData*)as->user_path;
    00127   TileIndex from = current->tile;
    00128   TileIndex to = fstd->dest_coords;
    00129   uint dist;
    00130
    00131   /* for train-stations, we are going to aim for the closest station tile */
    00132   if (as->user_data[NPF_TYPE] == TRANSPORT_RAIL && fstd->station_index != INVALID_STATION)
    00133     to = CalcClosestStationTile(fstd->station_index, from);
    00134
    00135   if (as->user_data[NPF_TYPE] == TRANSPORT_ROAD) {
    00136     /* Since roads only have diagonal pieces, we use manhattan distance here */
    00137     dist = DistanceManhattan(from, to) * NPF_TILE_LENGTH;
    00138   } else {
    00139     /* Ships and trains can also go diagonal, so the minimum distance is shorter */
    00140     dist = NPFDistanceTrack(from, to);
    00141   }
    00142
    00143   DEBUG(npf, 4, "Calculating H for: (%d, %d). Result: %d", TileX(current->tile), TileY(current->tile), dist);
    00144
    00145   if (dist < ftd->best_bird_dist) {
    00146     ftd->best_bird_dist = dist;
    00147     ftd->best_trackdir = (Trackdir)current->user_data[NPF_TRACKDIR_CHOICE];
    00148   }
    00149   return dist;
    00150 }
    00151
    00152
    00153 /* Fills AyStarNode.user_data[NPF_TRACKDIRCHOICE] with the chosen direction to
    00154  * get here, either getting it from the current choice or from the parent's
    00155  * choice */
    00156 static void NPFFillTrackdirChoice(AyStarNode* current, OpenListNode* parent)
    00157 {
    00158   if (parent->path.parent == NULL) {
    00159     Trackdir trackdir = (Trackdir)current->direction;
    00160     /* This is a first order decision, so we'd better save the
    00161      * direction we chose */
    00162     current->user_data[NPF_TRACKDIR_CHOICE] = trackdir;
    00163     DEBUG(npf, 6, "Saving trackdir: 0x%X", trackdir);
    00164   } else {
    00165     /* We've already made the decision, so just save our parent's decision */
    00166     current->user_data[NPF_TRACKDIR_CHOICE] = parent->path.node.user_data[NPF_TRACKDIR_CHOICE];
    00167   }
    00168 }
    00169
    00170 /* Will return the cost of the tunnel. If it is an entry, it will return the
    00171  * cost of that tile. If the tile is an exit, it will return the tunnel length
    00172  * including the exit tile. Requires that this is a Tunnel tile */
    00173 static uint NPFTunnelCost(AyStarNode* current)
    00174 {
    00175   DiagDirection exitdir = TrackdirToExitdir((Trackdir)current->direction);
    00176   TileIndex tile = current->tile;
    00177   if (GetTunnelBridgeDirection(tile) == ReverseDiagDir(exitdir)) {
    00178     /* We just popped out if this tunnel, since were
    00179      * facing the tunnel exit */
    00180     return NPF_TILE_LENGTH * (GetTunnelBridgeLength(current->tile, GetOtherTunnelEnd(current->tile)) + 1);
    00181     /* @todo: Penalty for tunnels? */
    00182   } else {
    00183     /* We are entering the tunnel, the enter tile is just a
    00184      * straight track */
    00185     return NPF_TILE_LENGTH;
    00186   }
    00187 }
    00188
    00189 static inline uint NPFBridgeCost(AyStarNode *current)
    00190 {
    00191   return NPF_TILE_LENGTH * GetTunnelBridgeLength(current->tile, GetOtherBridgeEnd(current->tile));
    00192 }
    00193
    00194 static uint NPFSlopeCost(AyStarNode* current)
    00195 {
    00196   TileIndex next = current->tile + TileOffsByDiagDir(TrackdirToExitdir((Trackdir)current->direction));
    00197
    00198   /* Get center of tiles */
    00199   int x1 = TileX(current->tile) * TILE_SIZE + TILE_SIZE / 2;
    00200   int y1 = TileY(current->tile) * TILE_SIZE + TILE_SIZE / 2;
    00201   int x2 = TileX(next) * TILE_SIZE + TILE_SIZE / 2;
    00202   int y2 = TileY(next) * TILE_SIZE + TILE_SIZE / 2;
    00203
    00204   int dx4 = (x2 - x1) / 4;
    00205   int dy4 = (y2 - y1) / 4;
    00206
    00207   /* Get the height on both sides of the tile edge.
    00208    * Avoid testing the height on the tile-center. This will fail for halftile-foundations.
    00209    */
    00210   int z1 = GetSlopeZ(x1 + dx4, y1 + dy4);
    00211   int z2 = GetSlopeZ(x2 - dx4, y2 - dy4);
    00212
    00213   if (z2 - z1 > 1) {
    00214     /* Slope up */
    00215     return _patches.npf_rail_slope_penalty;
    00216   }
    00217   return 0;
    00218   /* Should we give a bonus for slope down? Probably not, we
    00219    * could just substract that bonus from the penalty, because
    00220    * there is only one level of steepness... */
    00221 }
    00222
    00227 static void NPFMarkTile(TileIndex tile)
    00228 {
    00229 #ifndef NO_DEBUG_MESSAGES
    00230   if (_debug_npf_level < 1 || _networking) return;
    00231   switch (GetTileType(tile)) {
    00232     case MP_RAILWAY:
    00233       /* DEBUG: mark visited tiles by mowing the grass under them ;-) */
    00234       if (!IsTileDepotType(tile, TRANSPORT_RAIL)) {
    00235         SetRailGroundType(tile, RAIL_GROUND_BARREN);
    00236         MarkTileDirtyByTile(tile);
    00237       }
    00238       break;
    00239
    00240     case MP_ROAD:
    00241       if (!IsTileDepotType(tile, TRANSPORT_ROAD)) {
    00242         SetRoadside(tile, ROADSIDE_BARREN);
    00243         MarkTileDirtyByTile(tile);
    00244       }
    00245       break;
    00246
    00247     default:
    00248       break;
    00249   }
    00250 #endif
    00251 }
    00252
    00253 static int32 NPFWaterPathCost(AyStar* as, AyStarNode* current, OpenListNode* parent)
    00254 {
    00255   /* TileIndex tile = current->tile; */
    00256   int32 cost = 0;
    00257   Trackdir trackdir = (Trackdir)current->direction;
    00258
    00259   cost = _trackdir_length[trackdir]; // Should be different for diagonal tracks
    00260
    00261   if (IsBuoyTile(current->tile) && IsDiagonalTrackdir(trackdir))
    00262     cost += _patches.npf_buoy_penalty; // A small penalty for going over buoys
    00263
    00264   if (current->direction != NextTrackdir((Trackdir)parent->path.node.direction))
    00265     cost += _patches.npf_water_curve_penalty;
    00266
    00267   /* @todo More penalties? */
    00268
    00269   return cost;
    00270 }
    00271
    00272 /* Determine the cost of this node, for road tracks */
    00273 static int32 NPFRoadPathCost(AyStar* as, AyStarNode* current, OpenListNode* parent)
    00274 {
    00275   TileIndex tile = current->tile;
    00276   int32 cost = 0;
    00277
    00278   /* Determine base length */
    00279   switch (GetTileType(tile)) {
    00280     case MP_TUNNELBRIDGE:
    00281       cost = IsTunnel(tile) ? NPFTunnelCost(current) : NPFBridgeCost(current);
    00282       break;
    00283
    00284     case MP_ROAD:
    00285       cost = NPF_TILE_LENGTH;
    00286       /* Increase the cost for level crossings */
    00287       if (IsLevelCrossing(tile)) cost += _patches.npf_crossing_penalty;
    00288       break;
    00289
    00290     case MP_STATION:
    00291       cost = NPF_TILE_LENGTH;
    00292       /* Increase the cost for drive-through road stops */
    00293       if (IsDriveThroughStopTile(tile)) cost += _patches.npf_road_drive_through_penalty;
    00294       break;
    00295
    00296     default:
    00297       break;
    00298   }
    00299
    00300   /* Determine extra costs */
    00301
    00302   /* Check for slope */
    00303   cost += NPFSlopeCost(current);
    00304
    00305   /* Check for turns. Road vehicles only really drive diagonal, turns are
    00306    * represented by non-diagonal tracks */
    00307   if (!IsDiagonalTrackdir((Trackdir)current->direction))
    00308     cost += _patches.npf_road_curve_penalty;
    00309
    00310   NPFMarkTile(tile);
    00311   DEBUG(npf, 4, "Calculating G for: (%d, %d). Result: %d", TileX(current->tile), TileY(current->tile), cost);
    00312   return cost;
    00313 }
    00314
    00315
    00316 /* Determine the cost of this node, for railway tracks */
    00317 static int32 NPFRailPathCost(AyStar* as, AyStarNode* current, OpenListNode* parent)
    00318 {
    00319   TileIndex tile = current->tile;
    00320   Trackdir trackdir = (Trackdir)current->direction;
    00321   int32 cost = 0;
    00322   /* HACK: We create a OpenListNode manually, so we can call EndNodeCheck */
    00323   OpenListNode new_node;
    00324
    00325   /* Determine base length */
    00326   switch (GetTileType(tile)) {
    00327     case MP_TUNNELBRIDGE:
    00328       cost = IsTunnel(tile) ? NPFTunnelCost(current) : NPFBridgeCost(current);
    00329       break;
    00330
    00331     case MP_RAILWAY:
    00332       cost = _trackdir_length[trackdir]; /* Should be different for diagonal tracks */
    00333       break;
    00334
    00335     case MP_ROAD: /* Railway crossing */
    00336       cost = NPF_TILE_LENGTH;
    00337       break;
    00338
    00339     case MP_STATION:
    00340       /* We give a station tile a penalty. Logically we would only want to give
    00341        * station tiles that are not our destination this penalty. This would
    00342        * discourage trains to drive through busy stations. But, we can just
    00343        * give any station tile a penalty, because every possible route will get
    00344        * this penalty exactly once, on its end tile (if it's a station) and it
    00345        * will therefore not make a difference. */
    00346       cost = NPF_TILE_LENGTH + _patches.npf_rail_station_penalty;
    00347       break;
    00348
    00349     default:
    00350       break;
    00351   }
    00352
    00353   /* Determine extra costs */
    00354
    00355   /* Check for signals */
    00356   if (IsTileType(tile, MP_RAILWAY) && HasSignalOnTrackdir(tile, trackdir)) {
    00357     /* Ordinary track with signals */
    00358     if (GetSignalStateByTrackdir(tile, trackdir) == SIGNAL_STATE_RED) {
    00359       /* Signal facing us is red */
    00360       if (!NPFGetFlag(current, NPF_FLAG_SEEN_SIGNAL)) {
    00361         /* Penalize the first signal we
    00362          * encounter, if it is red */
    00363
    00364         /* Is this a presignal exit or combo? */
    00365         SignalType sigtype = GetSignalType(tile, TrackdirToTrack(trackdir));
    00366         if (sigtype == SIGTYPE_EXIT || sigtype == SIGTYPE_COMBO) {
    00367           /* Penalise exit and combo signals differently (heavier) */
    00368           cost += _patches.npf_rail_firstred_exit_penalty;
    00369         } else {
    00370           cost += _patches.npf_rail_firstred_penalty;
    00371         }
    00372       }
    00373       /* Record the state of this signal */
    00374       NPFSetFlag(current, NPF_FLAG_LAST_SIGNAL_RED, true);
    00375     } else {
    00376       /* Record the state of this signal */
    00377       NPFSetFlag(current, NPF_FLAG_LAST_SIGNAL_RED, false);
    00378     }
    00379     NPFSetFlag(current, NPF_FLAG_SEEN_SIGNAL, true);
    00380   }
    00381
    00382   /* Penalise the tile if it is a target tile and the last signal was
    00383    * red */
    00384   /* HACK: We create a new_node here so we can call EndNodeCheck. Ugly as hell
    00385    * of course... */
    00386   new_node.path.node = *current;
    00387   if (as->EndNodeCheck(as, &new_node) == AYSTAR_FOUND_END_NODE && NPFGetFlag(current, NPF_FLAG_LAST_SIGNAL_RED))
    00388     cost += _patches.npf_rail_lastred_penalty;
    00389
    00390   /* Check for slope */
    00391   cost += NPFSlopeCost(current);
    00392
    00393   /* Check for turns */
    00394   if (current->direction != NextTrackdir((Trackdir)parent->path.node.direction))
    00395     cost += _patches.npf_rail_curve_penalty;
    00396   /*TODO, with realistic acceleration, also the amount of straight track between
    00397    *      curves should be taken into account, as this affects the speed limit. */
    00398
    00399   /* Check for reverse in depot */
    00400   if (IsTileDepotType(tile, TRANSPORT_RAIL) && as->EndNodeCheck(as, &new_node) != AYSTAR_FOUND_END_NODE) {
    00401     /* Penalise any depot tile that is not the last tile in the path. This
    00402      * _should_ penalise every occurence of reversing in a depot (and only
    00403      * that) */
    00404     cost += _patches.npf_rail_depot_reverse_penalty;
    00405   }
    00406
    00407   /* Check for occupied track */
    00408   //TODO
    00409
    00410   NPFMarkTile(tile);
    00411   DEBUG(npf, 4, "Calculating G for: (%d, %d). Result: %d", TileX(current->tile), TileY(current->tile), cost);
    00412   return cost;
    00413 }
    00414
    00415 /* Will find any depot */
    00416 static int32 NPFFindDepot(AyStar* as, OpenListNode *current)
    00417 {
    00418   /* It's not worth caching the result with NPF_FLAG_IS_TARGET here as below,
    00419    * since checking the cache not that much faster than the actual check */
    00420   return IsTileDepotType(current->path.node.tile, (TransportType)as->user_data[NPF_TYPE]) ?
    00421     AYSTAR_FOUND_END_NODE : AYSTAR_DONE;
    00422 }
    00423
    00424 /* Will find a station identified using the NPFFindStationOrTileData */
    00425 static int32 NPFFindStationOrTile(AyStar* as, OpenListNode *current)
    00426 {
    00427   NPFFindStationOrTileData* fstd = (NPFFindStationOrTileData*)as->user_target;
    00428   AyStarNode *node = &current->path.node;
    00429   TileIndex tile = node->tile;
    00430
    00431   /* If GetNeighbours said we could get here, we assume the station type
    00432    * is correct */
    00433   if (
    00434     (fstd->station_index == INVALID_STATION && tile == fstd->dest_coords) || /* We've found the tile, or */
    00435     (IsTileType(tile, MP_STATION) && GetStationIndex(tile) == fstd->station_index) /* the station */
    00436   ) {
    00437     return AYSTAR_FOUND_END_NODE;
    00438   } else {
    00439     return AYSTAR_DONE;
    00440   }
    00441 }
    00442
    00443 /* To be called when current contains the (shortest route to) the target node.
    00444  * Will fill the contents of the NPFFoundTargetData using
    00445  * AyStarNode[NPF_TRACKDIR_CHOICE].
    00446  */
    00447 static void NPFSaveTargetData(AyStar* as, OpenListNode* current)
    00448 {
    00449   NPFFoundTargetData* ftd = (NPFFoundTargetData*)as->user_path;
    00450   ftd->best_trackdir = (Trackdir)current->path.node.user_data[NPF_TRACKDIR_CHOICE];
    00451   ftd->best_path_dist = current->g;
    00452   ftd->best_bird_dist = 0;
    00453   ftd->node = current->path.node;
    00454 }
    00455
    00465 static bool CanEnterTileOwnerCheck(Owner owner, TileIndex tile, DiagDirection enterdir)
    00466 {
    00467   if (IsTileType(tile, MP_RAILWAY) ||           /* Rail tile (also rail depot) */
    00468       IsRailwayStationTile(tile) ||               /* Rail station tile */
    00469       IsTileDepotType(tile, TRANSPORT_ROAD) ||  /* Road depot tile */
    00470       IsStandardRoadStopTile(tile)) { /* Road station tile (but not drive-through stops) */
    00471     return IsTileOwner(tile, owner); /* You need to own these tiles entirely to use them */
    00472   }
    00473
    00474   switch (GetTileType(tile)) {
    00475     case MP_ROAD:
    00476       /* rail-road crossing : are we looking at the railway part? */
    00477       if (IsLevelCrossing(tile) &&
    00478           DiagDirToAxis(enterdir) != GetCrossingRoadAxis(tile)) {
    00479         return IsTileOwner(tile, owner); /* Railway needs owner check, while the street is public */
    00480       }
    00481       break;
    00482
    00483     case MP_TUNNELBRIDGE:
    00484       if (GetTunnelBridgeTransportType(tile) == TRANSPORT_RAIL) {
    00485         return IsTileOwner(tile, owner);
    00486       }
    00487       break;
    00488
    00489     default:
    00490       break;
    00491   }
    00492
    00493   return true; // no need to check
    00494 }
    00495
    00496
    00500 static DiagDirection GetDepotDirection(TileIndex tile, TransportType type)
    00501 {
    00502   assert(IsTileDepotType(tile, type));
    00503
    00504   switch (type) {
    00505     case TRANSPORT_RAIL:  return GetRailDepotDirection(tile);
    00506     case TRANSPORT_ROAD:  return GetRoadDepotDirection(tile);
    00507     case TRANSPORT_WATER: return GetShipDepotDirection(tile);
    00508     default: return INVALID_DIAGDIR; /* Not reached */
    00509   }
    00510 }
    00511
    00513 static DiagDirection GetSingleTramBit(TileIndex tile)
    00514 {
    00515   if (IsNormalRoadTile(tile)) {
    00516     RoadBits rb = GetRoadBits(tile, ROADTYPE_TRAM);
    00517     switch (rb) {
    00518       case ROAD_NW: return DIAGDIR_NW;
    00519       case ROAD_SW: return DIAGDIR_SW;
    00520       case ROAD_SE: return DIAGDIR_SE;
    00521       case ROAD_NE: return DIAGDIR_NE;
    00522       default: break;
    00523     }
    00524   }
    00525   return INVALID_DIAGDIR;
    00526 }
    00527
    00538 static DiagDirection GetTileSingleEntry(TileIndex tile, TransportType type, uint subtype)
    00539 {
    00540   if (type != TRANSPORT_WATER && IsTileDepotType(tile, type)) return GetDepotDirection(tile, type);
    00541
    00542   if (type == TRANSPORT_ROAD) {
    00543     if (IsStandardRoadStopTile(tile)) return GetRoadStopDir(tile);
    00544     if (HasBit(subtype, ROADTYPE_TRAM)) return GetSingleTramBit(tile);
    00545   }
    00546
    00547   return INVALID_DIAGDIR;
    00548 }
    00549
    00559 static inline bool ForceReverse(TileIndex tile, DiagDirection dir, TransportType type, uint subtype)
    00560 {
    00561   DiagDirection single_entry = GetTileSingleEntry(tile, type, subtype);
    00562   return single_entry != INVALID_DIAGDIR && single_entry != dir;
    00563 }
    00564
    00576 static bool CanEnterTile(TileIndex tile, DiagDirection dir, TransportType type, uint subtype, RailTypes railtypes, Owner owner)
    00577 {
    00578   /* Check tunnel entries and bridge ramps */
    00579   if (IsTileType(tile, MP_TUNNELBRIDGE) && GetTunnelBridgeDirection(tile) != dir) return false;
    00580
    00581   /* Test ownership */
    00582   if (!CanEnterTileOwnerCheck(owner, tile, dir)) return false;
    00583
    00584   /* check correct rail type (mono, maglev, etc) */
    00585   if (type == TRANSPORT_RAIL) {
    00586     RailType rail_type = GetTileRailType(tile);
    00587     if (!HasBit(railtypes, rail_type)) return false;
    00588   }
    00589
    00590   /* Depots, standard roadstops and single tram bits can only be entered from one direction */
    00591   DiagDirection single_entry = GetTileSingleEntry(tile, type, subtype);
    00592   if (single_entry != INVALID_DIAGDIR && single_entry != ReverseDiagDir(dir)) return false;
    00593
    00594   return true;
    00595 }
    00596
    00608 static TrackdirBits GetDriveableTrackdirBits(TileIndex dst_tile, Trackdir src_trackdir, TransportType type, uint subtype)
    00609 {
    00610   TrackdirBits trackdirbits = TrackStatusToTrackdirBits(GetTileTrackStatus(dst_tile, type, subtype));
    00611
    00612   if (trackdirbits == 0 && type == TRANSPORT_ROAD && HasBit(subtype, ROADTYPE_TRAM)) {
    00613     /* GetTileTrackStatus() returns 0 for single tram bits.
    00614      * As we cannot change it there (easily) without breaking something, change it here */
    00615     switch (GetSingleTramBit(dst_tile)) {
    00616       case DIAGDIR_NE:
    00617       case DIAGDIR_SW:
    00618         trackdirbits = TRACKDIR_BIT_X_NE | TRACKDIR_BIT_X_SW;
    00619         break;
    00620
    00621       case DIAGDIR_NW:
    00622       case DIAGDIR_SE:
    00623         trackdirbits = TRACKDIR_BIT_Y_NW | TRACKDIR_BIT_Y_SE;
    00624         break;
    00625
    00626       default: break;
    00627     }
    00628   }
    00629
    00630   DEBUG(npf, 4, "Next node: (%d, %d) [%d], possible trackdirs: 0x%X", TileX(dst_tile), TileY(dst_tile), dst_tile, trackdirbits);
    00631
    00632   /* Select only trackdirs we can reach from our current trackdir */
    00633   trackdirbits &= TrackdirReachesTrackdirs(src_trackdir);
    00634
    00635   /* Filter out trackdirs that would make 90 deg turns for trains */
    00636   if (_patches.forbid_90_deg && (type == TRANSPORT_RAIL || type == TRANSPORT_WATER)) trackdirbits &= ~TrackdirCrossesTrackdirs(src_trackdir);
    00637
    00638   DEBUG(npf, 6, "After filtering: (%d, %d), possible trackdirs: 0x%X", TileX(dst_tile), TileY(dst_tile), trackdirbits);
    00639
    00640   return trackdirbits;
    00641 }
    00642
    00643
    00644 /* Will just follow the results of GetTileTrackStatus concerning where we can
    00645  * go and where not. Uses AyStar.user_data[NPF_TYPE] as the transport type and
    00646  * an argument to GetTileTrackStatus. Will skip tunnels, meaning that the
    00647  * entry and exit are neighbours. Will fill
    00648  * AyStarNode.user_data[NPF_TRACKDIR_CHOICE] with an appropriate value, and
    00649  * copy AyStarNode.user_data[NPF_NODE_FLAGS] from the parent */
    00650 static void NPFFollowTrack(AyStar* aystar, OpenListNode* current)
    00651 {
    00652   /* We leave src_tile on track src_trackdir in direction src_exitdir */
    00653   Trackdir src_trackdir = (Trackdir)current->path.node.direction;
    00654   TileIndex src_tile = current->path.node.tile;
    00655   DiagDirection src_exitdir = TrackdirToExitdir(src_trackdir);
    00656
    00657   /* Is src_tile valid, and can be used?
    00658    * When choosing track on a junction src_tile is the tile neighboured to the junction wrt. exitdir.
    00659    * 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. */
    00660   bool ignore_src_tile = (current->path.parent == NULL && NPFGetFlag(&current->path.node, NPF_FLAG_IGNORE_START_TILE));
    00661
    00662   /* Information about the vehicle: TransportType (road/rail/water) and SubType (compatible rail/road types) */
    00663   TransportType type = (TransportType)aystar->user_data[NPF_TYPE];
    00664   uint subtype = aystar->user_data[NPF_SUB_TYPE];
    00665
    00666   /* Initialize to 0, so we can jump out (return) somewhere an have no neighbours */
    00667   aystar->num_neighbours = 0;
    00668   DEBUG(npf, 4, "Expanding: (%d, %d, %d) [%d]", TileX(src_tile), TileY(src_tile), src_trackdir, src_tile);
    00669
    00670   /* We want to determine the tile we arrive, and which choices we have there */
    00671   TileIndex dst_tile;
    00672   TrackdirBits trackdirbits;
    00673
    00674   /* Find dest tile */
    00675   if (ignore_src_tile) {
    00676     /* Do not perform any checks that involve src_tile */
    00677     dst_tile = src_tile + TileOffsByDiagDir(src_exitdir);
    00678     trackdirbits = GetDriveableTrackdirBits(dst_tile, src_trackdir, type, subtype);
    00679   } else if (IsTileType(src_tile, MP_TUNNELBRIDGE) && GetTunnelBridgeDirection(src_tile) == src_exitdir) {
    00680     /* We drive through the wormhole and arrive on the other side */
    00681     dst_tile = GetOtherTunnelBridgeEnd(src_tile);
    00682     trackdirbits = TrackdirToTrackdirBits(src_trackdir);
    00683   } else if (ForceReverse(src_tile, src_exitdir, type, subtype)) {
    00684     /* We can only reverse on this tile */
    00685     dst_tile = src_tile;
    00686     src_trackdir = ReverseTrackdir(src_trackdir);
    00687     trackdirbits = TrackdirToTrackdirBits(src_trackdir);
    00688   } else {
    00689     /* We leave src_tile in src_exitdir and reach dst_tile */
    00690     dst_tile = AddTileIndexDiffCWrap(src_tile, TileIndexDiffCByDiagDir(src_exitdir));
    00691
    00692     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;
    00693
    00694     if (dst_tile == INVALID_TILE) {
    00695       /* We cannot enter the next tile. Road vehicles can reverse, others reach dead end */
    00696       if (type != TRANSPORT_ROAD || HasBit(subtype, ROADTYPE_TRAM)) return;
    00697
    00698       dst_tile = src_tile;
    00699       src_trackdir = ReverseTrackdir(src_trackdir);
    00700     }
    00701
    00702     trackdirbits = GetDriveableTrackdirBits(dst_tile, src_trackdir, type, subtype);
    00703
    00704     if (trackdirbits == 0) {
    00705       /* We cannot enter the next tile. Road vehicles can reverse, others reach dead end */
    00706       if (type != TRANSPORT_ROAD || HasBit(subtype, ROADTYPE_TRAM)) return;
    00707
    00708       dst_tile = src_tile;
    00709       src_trackdir = ReverseTrackdir(src_trackdir);
    00710
    00711       trackdirbits = GetDriveableTrackdirBits(dst_tile, src_trackdir, type, subtype);
    00712     }
    00713   }
    00714
    00715   /* Enumerate possible track */
    00716   uint i = 0;
    00717   while (trackdirbits != 0) {
    00718     Trackdir dst_trackdir = RemoveFirstTrackdir(&trackdirbits);
    00719     DEBUG(npf, 5, "Expanded into trackdir: %d, remaining trackdirs: 0x%X", dst_trackdir, trackdirbits);
    00720
    00721     /* Check for oneway signal against us */
    00722     if (IsTileType(dst_tile, MP_RAILWAY) && GetRailTileType(dst_tile) == RAIL_TILE_SIGNALS) {
    00723       if (HasSignalOnTrackdir(dst_tile, ReverseTrackdir(dst_trackdir)) && !HasSignalOnTrackdir(dst_tile, dst_trackdir))
    00724         /* if one way signal not pointing towards us, stop going in this direction. */
    00725         break;
    00726     }
    00727     {
    00728       /* We've found ourselves a neighbour :-) */
    00729       AyStarNode* neighbour = &aystar->neighbours[i];
    00730       neighbour->tile = dst_tile;
    00731       neighbour->direction = dst_trackdir;
    00732       /* Save user data */
    00733       neighbour->user_data[NPF_NODE_FLAGS] = current->path.node.user_data[NPF_NODE_FLAGS];
    00734       NPFFillTrackdirChoice(neighbour, current);
    00735     }
    00736     i++;
    00737   }
    00738   aystar->num_neighbours = i;
    00739 }
    00740
    00741 /*
    00742  * Plan a route to the specified target (which is checked by target_proc),
    00743  * from start1 and if not NULL, from start2 as well. The type of transport we
    00744  * are checking is in type. reverse_penalty is applied to all routes that
    00745  * originate from the second start node.
    00746  * When we are looking for one specific target (optionally multiple tiles), we
    00747  * should use a good heuristic to perform aystar search. When we search for
    00748  * multiple targets that are spread around, we should perform a breadth first
    00749  * search by specifiying CalcZero as our heuristic.
    00750  */
    00751 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)
    00752 {
    00753   int r;
    00754   NPFFoundTargetData result;
    00755
    00756   /* Initialize procs */
    00757   _npf_aystar.CalculateH = heuristic_proc;
    00758   _npf_aystar.EndNodeCheck = target_proc;
    00759   _npf_aystar.FoundEndNode = NPFSaveTargetData;
    00760   _npf_aystar.GetNeighbours = NPFFollowTrack;
    00761   switch (type) {
    00762     default: NOT_REACHED();
    00763     case TRANSPORT_RAIL:  _npf_aystar.CalculateG = NPFRailPathCost;  break;
    00764     case TRANSPORT_ROAD:  _npf_aystar.CalculateG = NPFRoadPathCost;  break;
    00765     case TRANSPORT_WATER: _npf_aystar.CalculateG = NPFWaterPathCost; break;
    00766   }
    00767
    00768   /* Initialize Start Node(s) */
    00769   start1->user_data[NPF_TRACKDIR_CHOICE] = INVALID_TRACKDIR;
    00770   start1->user_data[NPF_NODE_FLAGS] = 0;
    00771   NPFSetFlag(start1, NPF_FLAG_IGNORE_START_TILE, ignore_start_tile1);
    00772   _npf_aystar.addstart(&_npf_aystar, start1, 0);
    00773   if (start2) {
    00774     start2->user_data[NPF_TRACKDIR_CHOICE] = INVALID_TRACKDIR;
    00775     start2->user_data[NPF_NODE_FLAGS] = 0;
    00776     NPFSetFlag(start2, NPF_FLAG_IGNORE_START_TILE, ignore_start_tile2);
    00777     NPFSetFlag(start2, NPF_FLAG_REVERSE, true);
    00778     _npf_aystar.addstart(&_npf_aystar, start2, reverse_penalty);
    00779   }
    00780
    00781   /* Initialize result */
    00782   result.best_bird_dist = (uint)-1;
    00783   result.best_path_dist = (uint)-1;
    00784   result.best_trackdir = INVALID_TRACKDIR;
    00785   _npf_aystar.user_path = &result;
    00786
    00787   /* Initialize target */
    00788   _npf_aystar.user_target = target;
    00789
    00790   /* Initialize user_data */
    00791   _npf_aystar.user_data[NPF_TYPE] = type;
    00792   _npf_aystar.user_data[NPF_SUB_TYPE] = sub_type;
    00793   _npf_aystar.user_data[NPF_OWNER] = owner;
    00794   _npf_aystar.user_data[NPF_RAILTYPES] = railtypes;
    00795
    00796   /* GO! */
    00797   r = AyStarMain_Main(&_npf_aystar);
    00798   assert(r != AYSTAR_STILL_BUSY);
    00799
    00800   if (result.best_bird_dist != 0) {
    00801     if (target != NULL) {
    00802       DEBUG(npf, 1, "Could not find route to tile 0x%X from 0x%X.", target->dest_coords, start1->tile);
    00803     } else {
    00804       /* Assumption: target == NULL, so we are looking for a depot */
    00805       DEBUG(npf, 1, "Could not find route to a depot from tile 0x%X.", start1->tile);
    00806     }
    00807
    00808   }
    00809   return result;
    00810 }
    00811
    00812 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)
    00813 {
    00814   AyStarNode start1;
    00815   AyStarNode start2;
    00816
    00817   start1.tile = tile1;
    00818   start2.tile = tile2;
    00819   /* We set this in case the target is also the start tile, we will just
    00820    * return a not found then */
    00821   start1.user_data[NPF_TRACKDIR_CHOICE] = INVALID_TRACKDIR;
    00822   start1.direction = trackdir1;
    00823   start2.direction = trackdir2;
    00824   start2.user_data[NPF_TRACKDIR_CHOICE] = INVALID_TRACKDIR;
    00825
    00826   return NPFRouteInternal(&start1, ignore_start_tile1, (IsValidTile(tile2) ? &start2 : NULL), ignore_start_tile2, target, NPFFindStationOrTile, NPFCalcStationOrTileHeuristic, type, sub_type, owner, railtypes, 0);
    00827 }
    00828
    00829 NPFFoundTargetData NPFRouteToStationOrTile(TileIndex tile, Trackdir trackdir, bool ignore_start_tile, NPFFindStationOrTileData* target, TransportType type, uint sub_type, Owner owner, RailTypes railtypes)
    00830 {
    00831   return NPFRouteToStationOrTileTwoWay(tile, trackdir, ignore_start_tile, INVALID_TILE, INVALID_TRACKDIR, false, target, type, sub_type, owner, railtypes);
    00832 }
    00833
    00834 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)
    00835 {
    00836   AyStarNode start1;
    00837   AyStarNode start2;
    00838
    00839   start1.tile = tile1;
    00840   start2.tile = tile2;
    00841   /* We set this in case the target is also the start tile, we will just
    00842    * return a not found then */
    00843   start1.user_data[NPF_TRACKDIR_CHOICE] = INVALID_TRACKDIR;
    00844   start1.direction = trackdir1;
    00845   start2.direction = trackdir2;
    00846   start2.user_data[NPF_TRACKDIR_CHOICE] = INVALID_TRACKDIR;
    00847
    00848   /* perform a breadth first search. Target is NULL,
    00849    * since we are just looking for any depot...*/
    00850   return NPFRouteInternal(&start1, ignore_start_tile1, (IsValidTile(tile2) ? &start2 : NULL), ignore_start_tile2, NULL, NPFFindDepot, NPFCalcZero, type, sub_type, owner, railtypes, reverse_penalty);
    00851 }
    00852
    00853 NPFFoundTargetData NPFRouteToDepotBreadthFirst(TileIndex tile, Trackdir trackdir, bool ignore_start_tile, TransportType type, uint sub_type, Owner owner, RailTypes railtypes)
    00854 {
    00855   return NPFRouteToDepotBreadthFirstTwoWay(tile, trackdir, ignore_start_tile, INVALID_TILE, INVALID_TRACKDIR, false, type, sub_type, owner, railtypes, 0);
    00856 }
    00857
    00858 NPFFoundTargetData NPFRouteToDepotTrialError(TileIndex tile, Trackdir trackdir, bool ignore_start_tile, TransportType type, uint sub_type, Owner owner, RailTypes railtypes)
    00859 {
    00860   /* Okay, what we're gonna do. First, we look at all depots, calculate
    00861    * the manhatten distance to get to each depot. We then sort them by
    00862    * distance. We start by trying to plan a route to the closest, then
    00863    * the next closest, etc. We stop when the best route we have found so
    00864    * far, is shorter than the manhattan distance. This will obviously
    00865    * always find the closest depot. It will probably be most efficient
    00866    * for ships, since the heuristic will not be to far off then. I hope.
    00867    */
    00868   Queue depots;
    00869   int r;
    00870   NPFFoundTargetData best_result = {(uint)-1, (uint)-1, INVALID_TRACKDIR, {INVALID_TILE, 0, {0, 0}}};
    00871   NPFFoundTargetData result;
    00872   NPFFindStationOrTileData target;
    00873   AyStarNode start;
    00874   Depot* current;
    00875   Depot *depot;
    00876
    00877   init_InsSort(&depots);
    00878   /* Okay, let's find all depots that we can use first */
    00879   FOR_ALL_DEPOTS(depot) {
    00880     /* Check if this is really a valid depot, it is of the needed type and
    00881      * owner */
    00882     if (IsTileDepotType(depot->xy, type) && IsTileOwner(depot->xy, owner))
    00883       /* If so, let's add it to the queue, sorted by distance */
    00884       depots.push(&depots, depot, DistanceManhattan(tile, depot->xy));
    00885   }
    00886
    00887   /* Now, let's initialise the aystar */
    00888
    00889   /* Initialize procs */
    00890   _npf_aystar.CalculateH = NPFCalcStationOrTileHeuristic;
    00891   _npf_aystar.EndNodeCheck = NPFFindStationOrTile;
    00892   _npf_aystar.FoundEndNode = NPFSaveTargetData;
    00893   _npf_aystar.GetNeighbours = NPFFollowTrack;
    00894   switch (type) {
    00895     default: NOT_REACHED();
    00896     case TRANSPORT_RAIL:  _npf_aystar.CalculateG = NPFRailPathCost;  break;
    00897     case TRANSPORT_ROAD:  _npf_aystar.CalculateG = NPFRoadPathCost;  break;
    00898     case TRANSPORT_WATER: _npf_aystar.CalculateG = NPFWaterPathCost; break;
    00899   }
    00900
    00901   /* Initialize target */
    00902   target.station_index = INVALID_STATION; /* We will initialize dest_coords inside the loop below */
    00903   _npf_aystar.user_target = &target;
    00904
    00905   /* Initialize user_data */
    00906   _npf_aystar.user_data[NPF_TYPE] = type;
    00907   _npf_aystar.user_data[NPF_SUB_TYPE] = sub_type;
    00908   _npf_aystar.user_data[NPF_OWNER] = owner;
    00909
    00910   /* Initialize Start Node */
    00911   start.tile = tile;
    00912   start.direction = trackdir; /* We will initialize user_data inside the loop below */
    00913
    00914   /* Initialize Result */
    00915   _npf_aystar.user_path = &result;
    00916   best_result.best_path_dist = (uint)-1;
    00917   best_result.best_bird_dist = (uint)-1;
    00918
    00919   /* Just iterate the depots in order of increasing distance */
    00920   while ((current = (Depot*)depots.pop(&depots))) {
    00921     /* Check to see if we already have a path shorter than this
    00922      * depot's manhattan distance. HACK: We call DistanceManhattan
    00923      * again, we should probably modify the queue to give us that
    00924      * value... */
    00925     if ( DistanceManhattan(tile, current->xy * NPF_TILE_LENGTH) > best_result.best_path_dist)
    00926       break;
    00927
    00928     /* Initialize Start Node */
    00929     /* We set this in case the target is also the start tile, we will just
    00930      * return a not found then */
    00931     start.user_data[NPF_TRACKDIR_CHOICE] = INVALID_TRACKDIR;
    00932     start.user_data[NPF_NODE_FLAGS] = 0;
    00933     NPFSetFlag(&start, NPF_FLAG_IGNORE_START_TILE, ignore_start_tile);
    00934     _npf_aystar.addstart(&_npf_aystar, &start, 0);
    00935
    00936     /* Initialize result */
    00937     result.best_bird_dist = (uint)-1;
    00938     result.best_path_dist = (uint)-1;
    00939     result.best_trackdir = INVALID_TRACKDIR;
    00940
    00941     /* Initialize target */
    00942     target.dest_coords = current->xy;
    00943
    00944     /* GO! */
    00945     r = AyStarMain_Main(&_npf_aystar);
    00946     assert(r != AYSTAR_STILL_BUSY);
    00947
    00948     /* This depot is closer */
    00949     if (result.best_path_dist < best_result.best_path_dist)
    00950       best_result = result;
    00951   }
    00952   if (result.best_bird_dist != 0) {
    00953     DEBUG(npf, 1, "Could not find route to any depot from tile 0x%X.", tile);
    00954   }
    00955   return best_result;
    00956 }
    00957
    00958 void InitializeNPF()
    00959 {
    00960   static bool first_init = true;
    00961   if (first_init) {
    00962     first_init = false;
    00963     init_AyStar(&_npf_aystar, NPFHash, NPF_HASH_SIZE);
    00964   } else {
    00965     AyStarMain_Clear(&_npf_aystar);
    00966   }
    00967   _npf_aystar.loops_per_tick = 0;
    00968   _npf_aystar.max_path_cost = 0;
    00969   //_npf_aystar.max_search_nodes = 0;
    00970   /* We will limit the number of nodes for now, until we have a better
    00971    * solution to really fix performance */
    00972   _npf_aystar.max_search_nodes = _patches.npf_max_search_nodes;
    00973 }
    00974
    00975 void NPFFillWithOrderData(NPFFindStationOrTileData* fstd, Vehicle* v)
    00976 {
    00977   /* Ships don't really reach their stations, but the tile in front. So don't
    00978    * save the station id for ships. For roadvehs we don't store it either,
    00979    * because multistop depends on vehicles actually reaching the exact
    00980    * dest_tile, not just any stop of that station.
    00981    * So only for train orders to stations we fill fstd->station_index, for all
    00982    * others only dest_coords */
    00983   if (v->current_order.type == OT_GOTO_STATION && v->type == VEH_TRAIN) {
    00984     fstd->station_index = v->current_order.dest;
    00985     /* Let's take the closest tile of the station as our target for trains */
    00986     fstd->dest_coords = CalcClosestStationTile(v->current_order.dest, v->tile);
    00987   } else {
    00988     fstd->dest_coords = v->dest_tile;
    00989     fstd->station_index = INVALID_STATION;
    00990   }
    00991 }