OpenTTD
npf.cpp
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1 /* $Id: npf.cpp 26482 2014-04-23 20:13:33Z rubidium $ */
2 
3 /*
4  * This file is part of OpenTTD.
5  * 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.
6  * 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.
7  * 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/>.
8  */
9 
12 #include "../../stdafx.h"
13 #include "../../network/network.h"
14 #include "../../viewport_func.h"
15 #include "../../ship.h"
16 #include "../../roadstop_base.h"
17 #include "../pathfinder_func.h"
18 #include "../pathfinder_type.h"
19 #include "../follow_track.hpp"
20 #include "aystar.h"
21 
22 #include "../../safeguards.h"
23 
24 static const uint NPF_HASH_BITS = 12;
25 /* Do no change below values */
26 static const uint NPF_HASH_SIZE = 1 << NPF_HASH_BITS;
27 static const uint NPF_HASH_HALFBITS = NPF_HASH_BITS / 2;
28 static const uint NPF_HASH_HALFMASK = (1 << NPF_HASH_HALFBITS) - 1;
29 
33  StationID station_index;
34  bool reserve_path;
37  const Vehicle *v;
38 };
39 
42  NPF_TYPE = 0,
46 };
47 
51  NPF_NODE_FLAGS,
52 };
53 
65 };
66 
73  bool res_okay;
74 };
75 
76 static AyStar _npf_aystar;
77 
78 /* The cost of each trackdir. A diagonal piece is the full NPF_TILE_LENGTH,
79  * the shorter piece is sqrt(2)/2*NPF_TILE_LENGTH =~ 0.7071
80  */
81 #define NPF_STRAIGHT_LENGTH (uint)(NPF_TILE_LENGTH * STRAIGHT_TRACK_LENGTH)
82 static const uint _trackdir_length[TRACKDIR_END] = {
83  NPF_TILE_LENGTH, NPF_TILE_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH,
84  0, 0,
85  NPF_TILE_LENGTH, NPF_TILE_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH
86 };
87 
91 static inline bool NPFGetFlag(const AyStarNode *node, NPFNodeFlag flag)
92 {
93  return HasBit(node->user_data[NPF_NODE_FLAGS], flag);
94 }
95 
99 static inline void NPFSetFlag(AyStarNode *node, NPFNodeFlag flag, bool value)
100 {
101  SB(node->user_data[NPF_NODE_FLAGS], flag, 1, value);
102 }
103 
111 {
112  const uint dx = Delta(TileX(t0), TileX(t1));
113  const uint dy = Delta(TileY(t0), TileY(t1));
114 
115  const uint straightTracks = 2 * min(dx, dy); // The number of straight (not full length) tracks
116  /* OPTIMISATION:
117  * Original: diagTracks = max(dx, dy) - min(dx,dy);
118  * Proof:
119  * (dx+dy) - straightTracks == (min + max) - straightTracks = min + max - 2 * min = max - min */
120  const uint diagTracks = dx + dy - straightTracks; // The number of diagonal (full tile length) tracks.
121 
122  /* Don't factor out NPF_TILE_LENGTH below, this will round values and lose
123  * precision */
124  return diagTracks * NPF_TILE_LENGTH + straightTracks * NPF_TILE_LENGTH * STRAIGHT_TRACK_LENGTH;
125 }
126 
134 static uint NPFHash(uint key1, uint key2)
135 {
136  /* TODO: think of a better hash? */
137  uint part1 = TileX(key1) & NPF_HASH_HALFMASK;
138  uint part2 = TileY(key1) & NPF_HASH_HALFMASK;
139 
140  assert(IsValidTrackdir((Trackdir)key2));
141  assert(IsValidTile(key1));
142  return ((part1 << NPF_HASH_HALFBITS | part2) + (NPF_HASH_SIZE * key2 / TRACKDIR_END)) % NPF_HASH_SIZE;
143 }
144 
145 static int32 NPFCalcZero(AyStar *as, AyStarNode *current, OpenListNode *parent)
146 {
147  return 0;
148 }
149 
150 /* Calculates the heuristic to the target station or tile. For train stations, it
151  * takes into account the direction of approach.
152  */
153 static int32 NPFCalcStationOrTileHeuristic(AyStar *as, AyStarNode *current, OpenListNode *parent)
154 {
155  NPFFindStationOrTileData *fstd = (NPFFindStationOrTileData*)as->user_target;
156  NPFFoundTargetData *ftd = (NPFFoundTargetData*)as->user_path;
157  TileIndex from = current->tile;
158  TileIndex to = fstd->dest_coords;
159  uint dist;
160 
161  /* for train-stations, we are going to aim for the closest station tile */
162  if (as->user_data[NPF_TYPE] != TRANSPORT_WATER && fstd->station_index != INVALID_STATION) {
163  to = CalcClosestStationTile(fstd->station_index, from, fstd->station_type);
164  }
165 
166  if (as->user_data[NPF_TYPE] == TRANSPORT_ROAD) {
167  /* Since roads only have diagonal pieces, we use manhattan distance here */
168  dist = DistanceManhattan(from, to) * NPF_TILE_LENGTH;
169  } else {
170  /* Ships and trains can also go diagonal, so the minimum distance is shorter */
171  dist = NPFDistanceTrack(from, to);
172  }
173 
174  DEBUG(npf, 4, "Calculating H for: (%d, %d). Result: %d", TileX(current->tile), TileY(current->tile), dist);
175 
176  if (dist < ftd->best_bird_dist) {
177  ftd->best_bird_dist = dist;
178  ftd->best_trackdir = (Trackdir)current->user_data[NPF_TRACKDIR_CHOICE];
179  }
180  return dist;
181 }
182 
183 
184 /* Fills AyStarNode.user_data[NPF_TRACKDIRCHOICE] with the chosen direction to
185  * get here, either getting it from the current choice or from the parent's
186  * choice */
187 static void NPFFillTrackdirChoice(AyStarNode *current, OpenListNode *parent)
188 {
189  if (parent->path.parent == NULL) {
190  Trackdir trackdir = current->direction;
191  /* This is a first order decision, so we'd better save the
192  * direction we chose */
193  current->user_data[NPF_TRACKDIR_CHOICE] = trackdir;
194  DEBUG(npf, 6, "Saving trackdir: 0x%X", trackdir);
195  } else {
196  /* We've already made the decision, so just save our parent's decision */
197  current->user_data[NPF_TRACKDIR_CHOICE] = parent->path.node.user_data[NPF_TRACKDIR_CHOICE];
198  }
199 }
200 
201 /* Will return the cost of the tunnel. If it is an entry, it will return the
202  * cost of that tile. If the tile is an exit, it will return the tunnel length
203  * including the exit tile. Requires that this is a Tunnel tile */
204 static uint NPFTunnelCost(AyStarNode *current)
205 {
206  DiagDirection exitdir = TrackdirToExitdir(current->direction);
207  TileIndex tile = current->tile;
208  if (GetTunnelBridgeDirection(tile) == ReverseDiagDir(exitdir)) {
209  /* We just popped out if this tunnel, since were
210  * facing the tunnel exit */
211  return NPF_TILE_LENGTH * (GetTunnelBridgeLength(current->tile, GetOtherTunnelEnd(current->tile)) + 1);
212  /* @todo: Penalty for tunnels? */
213  } else {
214  /* We are entering the tunnel, the enter tile is just a
215  * straight track */
216  return NPF_TILE_LENGTH;
217  }
218 }
219 
220 static inline uint NPFBridgeCost(AyStarNode *current)
221 {
222  return NPF_TILE_LENGTH * GetTunnelBridgeLength(current->tile, GetOtherBridgeEnd(current->tile));
223 }
224 
225 static uint NPFSlopeCost(AyStarNode *current)
226 {
227  TileIndex next = current->tile + TileOffsByDiagDir(TrackdirToExitdir(current->direction));
228 
229  /* Get center of tiles */
230  int x1 = TileX(current->tile) * TILE_SIZE + TILE_SIZE / 2;
231  int y1 = TileY(current->tile) * TILE_SIZE + TILE_SIZE / 2;
232  int x2 = TileX(next) * TILE_SIZE + TILE_SIZE / 2;
233  int y2 = TileY(next) * TILE_SIZE + TILE_SIZE / 2;
234 
235  int dx4 = (x2 - x1) / 4;
236  int dy4 = (y2 - y1) / 4;
237 
238  /* Get the height on both sides of the tile edge.
239  * Avoid testing the height on the tile-center. This will fail for halftile-foundations.
240  */
241  int z1 = GetSlopePixelZ(x1 + dx4, y1 + dy4);
242  int z2 = GetSlopePixelZ(x2 - dx4, y2 - dy4);
243 
244  if (z2 - z1 > 1) {
245  /* Slope up */
247  }
248  return 0;
249  /* Should we give a bonus for slope down? Probably not, we
250  * could just subtract that bonus from the penalty, because
251  * there is only one level of steepness... */
252 }
253 
254 static uint NPFReservedTrackCost(AyStarNode *current)
255 {
256  TileIndex tile = current->tile;
257  TrackBits track = TrackToTrackBits(TrackdirToTrack(current->direction));
258  TrackBits res = GetReservedTrackbits(tile);
259 
260  if (NPFGetFlag(current, NPF_FLAG_3RD_SIGNAL) || NPFGetFlag(current, NPF_FLAG_LAST_SIGNAL_BLOCK) || ((res & track) == TRACK_BIT_NONE && !TracksOverlap(res | track))) return 0;
261 
262  if (IsTileType(tile, MP_TUNNELBRIDGE)) {
263  DiagDirection exitdir = TrackdirToExitdir(current->direction);
264  if (GetTunnelBridgeDirection(tile) == ReverseDiagDir(exitdir)) {
266  }
267  }
269 }
270 
275 static void NPFMarkTile(TileIndex tile)
276 {
277 #ifndef NO_DEBUG_MESSAGES
278  if (_debug_npf_level < 1 || _networking) return;
279  switch (GetTileType(tile)) {
280  case MP_RAILWAY:
281  /* DEBUG: mark visited tiles by mowing the grass under them ;-) */
282  if (!IsRailDepot(tile)) {
283  SetRailGroundType(tile, RAIL_GROUND_BARREN);
284  MarkTileDirtyByTile(tile);
285  }
286  break;
287 
288  case MP_ROAD:
289  if (!IsRoadDepot(tile)) {
291  MarkTileDirtyByTile(tile);
292  }
293  break;
294 
295  default:
296  break;
297  }
298 #endif
299 }
300 
301 static int32 NPFWaterPathCost(AyStar *as, AyStarNode *current, OpenListNode *parent)
302 {
303  /* TileIndex tile = current->tile; */
304  int32 cost = 0;
305  Trackdir trackdir = current->direction;
306 
307  cost = _trackdir_length[trackdir]; // Should be different for diagonal tracks
308 
309  if (IsBuoyTile(current->tile) && IsDiagonalTrackdir(trackdir)) {
310  cost += _settings_game.pf.npf.npf_buoy_penalty; // A small penalty for going over buoys
311  }
312 
313  if (current->direction != NextTrackdir((Trackdir)parent->path.node.direction)) {
315  }
316 
317  /* @todo More penalties? */
318 
319  return cost;
320 }
321 
322 /* Determine the cost of this node, for road tracks */
323 static int32 NPFRoadPathCost(AyStar *as, AyStarNode *current, OpenListNode *parent)
324 {
325  TileIndex tile = current->tile;
326  int32 cost = 0;
327 
328  /* Determine base length */
329  switch (GetTileType(tile)) {
330  case MP_TUNNELBRIDGE:
331  cost = IsTunnel(tile) ? NPFTunnelCost(current) : NPFBridgeCost(current);
332  break;
333 
334  case MP_ROAD:
335  cost = NPF_TILE_LENGTH;
336  /* Increase the cost for level crossings */
338  break;
339 
340  case MP_STATION: {
341  cost = NPF_TILE_LENGTH;
342  const RoadStop *rs = RoadStop::GetByTile(tile, GetRoadStopType(tile));
343  if (IsDriveThroughStopTile(tile)) {
344  /* Increase the cost for drive-through road stops */
346  DiagDirection dir = TrackdirToExitdir(current->direction);
348  /* When we're the first road stop in a 'queue' of them we increase
349  * cost based on the fill percentage of the whole queue. */
350  const RoadStop::Entry *entry = rs->GetEntry(dir);
352  }
353  } else {
354  /* Increase cost for filled road stops */
355  cost += _settings_game.pf.npf.npf_road_bay_occupied_penalty * (!rs->IsFreeBay(0) + !rs->IsFreeBay(1)) / 2;
356  }
357  break;
358  }
359 
360  default:
361  break;
362  }
363 
364  /* Determine extra costs */
365 
366  /* Check for slope */
367  cost += NPFSlopeCost(current);
368 
369  /* Check for turns. Road vehicles only really drive diagonal, turns are
370  * represented by non-diagonal tracks */
371  if (!IsDiagonalTrackdir(current->direction)) {
373  }
374 
375  NPFMarkTile(tile);
376  DEBUG(npf, 4, "Calculating G for: (%d, %d). Result: %d", TileX(current->tile), TileY(current->tile), cost);
377  return cost;
378 }
379 
380 
381 /* Determine the cost of this node, for railway tracks */
382 static int32 NPFRailPathCost(AyStar *as, AyStarNode *current, OpenListNode *parent)
383 {
384  TileIndex tile = current->tile;
385  Trackdir trackdir = current->direction;
386  int32 cost = 0;
387  /* HACK: We create a OpenListNode manually, so we can call EndNodeCheck */
388  OpenListNode new_node;
389 
390  /* Determine base length */
391  switch (GetTileType(tile)) {
392  case MP_TUNNELBRIDGE:
393  cost = IsTunnel(tile) ? NPFTunnelCost(current) : NPFBridgeCost(current);
394  break;
395 
396  case MP_RAILWAY:
397  cost = _trackdir_length[trackdir]; // Should be different for diagonal tracks
398  break;
399 
400  case MP_ROAD: // Railway crossing
401  cost = NPF_TILE_LENGTH;
402  break;
403 
404  case MP_STATION:
405  /* We give a station tile a penalty. Logically we would only want to give
406  * station tiles that are not our destination this penalty. This would
407  * discourage trains to drive through busy stations. But, we can just
408  * give any station tile a penalty, because every possible route will get
409  * this penalty exactly once, on its end tile (if it's a station) and it
410  * will therefore not make a difference. */
412 
413  if (IsRailWaypoint(tile)) {
414  NPFFindStationOrTileData *fstd = (NPFFindStationOrTileData*)as->user_target;
415  if (fstd->v->current_order.IsType(OT_GOTO_WAYPOINT) && GetStationIndex(tile) == fstd->v->current_order.GetDestination()) {
416  /* This waypoint is our destination; maybe this isn't an unreserved
417  * one, so check that and if so see that as the last signal being
418  * red. This way waypoints near stations should work better. */
419  const Train *train = Train::From(fstd->v);
420  CFollowTrackRail ft(train);
421  TileIndex t = tile;
422  Trackdir td = trackdir;
423  while (ft.Follow(t, td)) {
424  assert(t != ft.m_new_tile);
425  t = ft.m_new_tile;
426  if (KillFirstBit(ft.m_new_td_bits) != TRACKDIR_BIT_NONE) {
427  /* We encountered a junction; it's going to be too complex to
428  * handle this perfectly, so just bail out. There is no simple
429  * free path, so try the other possibilities. */
430  td = INVALID_TRACKDIR;
431  break;
432  }
433  td = RemoveFirstTrackdir(&ft.m_new_td_bits);
434  /* If this is a safe waiting position we're done searching for it */
435  if (IsSafeWaitingPosition(train, t, td, true, _settings_game.pf.forbid_90_deg)) break;
436  }
437  if (td == INVALID_TRACKDIR ||
438  !IsSafeWaitingPosition(train, t, td, true, _settings_game.pf.forbid_90_deg) ||
441  }
442  }
443  }
444  break;
445 
446  default:
447  break;
448  }
449 
450  /* Determine extra costs */
451 
452  /* Check for signals */
453  if (IsTileType(tile, MP_RAILWAY)) {
454  if (HasSignalOnTrackdir(tile, trackdir)) {
455  SignalType sigtype = GetSignalType(tile, TrackdirToTrack(trackdir));
456  /* Ordinary track with signals */
457  if (GetSignalStateByTrackdir(tile, trackdir) == SIGNAL_STATE_RED) {
458  /* Signal facing us is red */
459  if (!NPFGetFlag(current, NPF_FLAG_SEEN_SIGNAL)) {
460  /* Penalize the first signal we
461  * encounter, if it is red */
462 
463  /* Is this a presignal exit or combo? */
464  if (!IsPbsSignal(sigtype)) {
465  if (sigtype == SIGTYPE_EXIT || sigtype == SIGTYPE_COMBO) {
466  /* Penalise exit and combo signals differently (heavier) */
468  } else {
470  }
471  }
472  }
473  /* Record the state of this signal. Path signals are assumed to
474  * be green as the signal state of them has no meaning for this. */
475  NPFSetFlag(current, NPF_FLAG_LAST_SIGNAL_RED, !IsPbsSignal(sigtype));
476  } else {
477  /* Record the state of this signal */
478  NPFSetFlag(current, NPF_FLAG_LAST_SIGNAL_RED, false);
479  }
480  if (NPFGetFlag(current, NPF_FLAG_SEEN_SIGNAL)) {
481  if (NPFGetFlag(current, NPF_FLAG_2ND_SIGNAL)) {
482  NPFSetFlag(current, NPF_FLAG_3RD_SIGNAL, true);
483  } else {
484  NPFSetFlag(current, NPF_FLAG_2ND_SIGNAL, true);
485  }
486  } else {
487  NPFSetFlag(current, NPF_FLAG_SEEN_SIGNAL, true);
488  }
489  NPFSetFlag(current, NPF_FLAG_LAST_SIGNAL_BLOCK, !IsPbsSignal(sigtype));
490  }
491 
492  if (HasPbsSignalOnTrackdir(tile, ReverseTrackdir(trackdir)) && !NPFGetFlag(current, NPF_FLAG_3RD_SIGNAL)) {
494  }
495  }
496 
497  /* Penalise the tile if it is a target tile and the last signal was
498  * red */
499  /* HACK: We create a new_node here so we can call EndNodeCheck. Ugly as hell
500  * of course... */
501  new_node.path.node = *current;
502  if (as->EndNodeCheck(as, &new_node) == AYSTAR_FOUND_END_NODE && NPFGetFlag(current, NPF_FLAG_LAST_SIGNAL_RED)) {
504  }
505 
506  /* Check for slope */
507  cost += NPFSlopeCost(current);
508 
509  /* Check for turns */
510  if (current->direction != NextTrackdir((Trackdir)parent->path.node.direction)) {
512  }
513  /* TODO, with realistic acceleration, also the amount of straight track between
514  * curves should be taken into account, as this affects the speed limit. */
515 
516  /* Check for reverse in depot */
517  if (IsRailDepotTile(tile) && as->EndNodeCheck(as, &new_node) != AYSTAR_FOUND_END_NODE) {
518  /* Penalise any depot tile that is not the last tile in the path. This
519  * _should_ penalise every occurrence of reversing in a depot (and only
520  * that) */
522  }
523 
524  /* Check for occupied track */
525  cost += NPFReservedTrackCost(current);
526 
527  NPFMarkTile(tile);
528  DEBUG(npf, 4, "Calculating G for: (%d, %d). Result: %d", TileX(current->tile), TileY(current->tile), cost);
529  return cost;
530 }
531 
532 /* Will find any depot */
533 static int32 NPFFindDepot(AyStar *as, OpenListNode *current)
534 {
535  /* It's not worth caching the result with NPF_FLAG_IS_TARGET here as below,
536  * since checking the cache not that much faster than the actual check */
537  return IsDepotTypeTile(current->path.node.tile, (TransportType)as->user_data[NPF_TYPE]) ?
539 }
540 
542 static int32 NPFFindSafeTile(AyStar *as, OpenListNode *current)
543 {
544  const Train *v = Train::From(((NPFFindStationOrTileData *)as->user_target)->v);
545 
546  return (IsSafeWaitingPosition(v, current->path.node.tile, current->path.node.direction, true, _settings_game.pf.forbid_90_deg) &&
547  IsWaitingPositionFree(v, current->path.node.tile, current->path.node.direction, _settings_game.pf.forbid_90_deg)) ?
549 }
550 
551 /* Will find a station identified using the NPFFindStationOrTileData */
552 static int32 NPFFindStationOrTile(AyStar *as, OpenListNode *current)
553 {
554  NPFFindStationOrTileData *fstd = (NPFFindStationOrTileData*)as->user_target;
555  AyStarNode *node = &current->path.node;
556  TileIndex tile = node->tile;
557 
558  if (fstd->station_index == INVALID_STATION && tile == fstd->dest_coords) return AYSTAR_FOUND_END_NODE;
559 
560  if (IsTileType(tile, MP_STATION) && GetStationIndex(tile) == fstd->station_index) {
561  if (fstd->v->type == VEH_TRAIN) return AYSTAR_FOUND_END_NODE;
562 
563  assert(fstd->v->type == VEH_ROAD);
564  /* Only if it is a valid station *and* we can stop there */
565  if (GetStationType(tile) == fstd->station_type && (fstd->not_articulated || IsDriveThroughStopTile(tile))) return AYSTAR_FOUND_END_NODE;
566  }
567  return AYSTAR_DONE;
568 }
569 
577 static const PathNode *FindSafePosition(PathNode *path, const Train *v)
578 {
579  /* If there is no signal, reserve the whole path. */
580  PathNode *sig = path;
581 
582  for (; path->parent != NULL; path = path->parent) {
583  if (IsSafeWaitingPosition(v, path->node.tile, path->node.direction, true, _settings_game.pf.forbid_90_deg)) {
584  sig = path;
585  }
586  }
587 
588  return sig;
589 }
590 
594 static void ClearPathReservation(const PathNode *start, const PathNode *end)
595 {
596  bool first_run = true;
597  for (; start != end; start = start->parent) {
598  if (IsRailStationTile(start->node.tile) && first_run) {
599  SetRailStationPlatformReservation(start->node.tile, TrackdirToExitdir(start->node.direction), false);
600  } else {
601  UnreserveRailTrack(start->node.tile, TrackdirToTrack(start->node.direction));
602  }
603  first_run = false;
604  }
605 }
606 
613 static void NPFSaveTargetData(AyStar *as, OpenListNode *current)
614 {
615  NPFFoundTargetData *ftd = (NPFFoundTargetData*)as->user_path;
616  ftd->best_trackdir = (Trackdir)current->path.node.user_data[NPF_TRACKDIR_CHOICE];
617  ftd->best_path_dist = current->g;
618  ftd->best_bird_dist = 0;
619  ftd->node = current->path.node;
620  ftd->res_okay = false;
621 
622  if (as->user_target != NULL && ((NPFFindStationOrTileData*)as->user_target)->reserve_path && as->user_data[NPF_TYPE] == TRANSPORT_RAIL) {
623  /* Path reservation is requested. */
624  const Train *v = Train::From(((NPFFindStationOrTileData *)as->user_target)->v);
625 
626  const PathNode *target = FindSafePosition(&current->path, v);
627  ftd->node = target->node;
628 
629  /* If the target is a station skip to platform end. */
630  if (IsRailStationTile(target->node.tile)) {
631  DiagDirection dir = TrackdirToExitdir(target->node.direction);
632  uint len = Station::GetByTile(target->node.tile)->GetPlatformLength(target->node.tile, dir);
633  TileIndex end_tile = TILE_ADD(target->node.tile, (len - 1) * TileOffsByDiagDir(dir));
634 
635  /* Update only end tile, trackdir of a station stays the same. */
636  ftd->node.tile = end_tile;
637  if (!IsWaitingPositionFree(v, end_tile, target->node.direction, _settings_game.pf.forbid_90_deg)) return;
638  SetRailStationPlatformReservation(target->node.tile, dir, true);
639  SetRailStationReservation(target->node.tile, false);
640  } else {
641  if (!IsWaitingPositionFree(v, target->node.tile, target->node.direction, _settings_game.pf.forbid_90_deg)) return;
642  }
643 
644  for (const PathNode *cur = target; cur->parent != NULL; cur = cur->parent) {
645  if (!TryReserveRailTrack(cur->node.tile, TrackdirToTrack(cur->node.direction))) {
646  /* Reservation failed, undo. */
647  ClearPathReservation(target, cur);
648  return;
649  }
650  }
651 
652  ftd->res_okay = true;
653  }
654 }
655 
665 static bool CanEnterTileOwnerCheck(Owner owner, TileIndex tile, DiagDirection enterdir)
666 {
667  if (IsTileType(tile, MP_RAILWAY) || // Rail tile (also rail depot)
668  HasStationTileRail(tile) || // Rail station tile/waypoint
669  IsRoadDepotTile(tile) || // Road depot tile
670  IsStandardRoadStopTile(tile)) { // Road station tile (but not drive-through stops)
671  return IsTileOwner(tile, owner); // You need to own these tiles entirely to use them
672  }
673 
674  switch (GetTileType(tile)) {
675  case MP_ROAD:
676  /* rail-road crossing : are we looking at the railway part? */
677  if (IsLevelCrossing(tile) &&
678  DiagDirToAxis(enterdir) != GetCrossingRoadAxis(tile)) {
679  return IsTileOwner(tile, owner); // Railway needs owner check, while the street is public
680  }
681  break;
682 
683  case MP_TUNNELBRIDGE:
685  return IsTileOwner(tile, owner);
686  }
687  break;
688 
689  default:
690  break;
691  }
692 
693  return true; // no need to check
694 }
695 
696 
701 {
702  assert(IsDepotTypeTile(tile, type));
703 
704  switch (type) {
705  case TRANSPORT_RAIL: return GetRailDepotDirection(tile);
706  case TRANSPORT_ROAD: return GetRoadDepotDirection(tile);
707  case TRANSPORT_WATER: return GetShipDepotDirection(tile);
708  default: return INVALID_DIAGDIR; // Not reached
709  }
710 }
711 
714 {
715  if (IsNormalRoadTile(tile)) {
716  RoadBits rb = GetRoadBits(tile, ROADTYPE_TRAM);
717  switch (rb) {
718  case ROAD_NW: return DIAGDIR_NW;
719  case ROAD_SW: return DIAGDIR_SW;
720  case ROAD_SE: return DIAGDIR_SE;
721  case ROAD_NE: return DIAGDIR_NE;
722  default: break;
723  }
724  }
725  return INVALID_DIAGDIR;
726 }
727 
738 static DiagDirection GetTileSingleEntry(TileIndex tile, TransportType type, uint subtype)
739 {
740  if (type != TRANSPORT_WATER && IsDepotTypeTile(tile, type)) return GetDepotDirection(tile, type);
741 
742  if (type == TRANSPORT_ROAD) {
743  if (IsStandardRoadStopTile(tile)) return GetRoadStopDir(tile);
744  if (HasBit(subtype, ROADTYPE_TRAM)) return GetSingleTramBit(tile);
745  }
746 
747  return INVALID_DIAGDIR;
748 }
749 
759 static inline bool ForceReverse(TileIndex tile, DiagDirection dir, TransportType type, uint subtype)
760 {
761  DiagDirection single_entry = GetTileSingleEntry(tile, type, subtype);
762  return single_entry != INVALID_DIAGDIR && single_entry != dir;
763 }
764 
776 static bool CanEnterTile(TileIndex tile, DiagDirection dir, TransportType type, uint subtype, RailTypes railtypes, Owner owner)
777 {
778  /* Check tunnel entries and bridge ramps */
779  if (IsTileType(tile, MP_TUNNELBRIDGE) && GetTunnelBridgeDirection(tile) != dir) return false;
780 
781  /* Test ownership */
782  if (!CanEnterTileOwnerCheck(owner, tile, dir)) return false;
783 
784  /* check correct rail type (mono, maglev, etc) */
785  if (type == TRANSPORT_RAIL) {
786  RailType rail_type = GetTileRailType(tile);
787  if (!HasBit(railtypes, rail_type)) return false;
788  }
789 
790  /* Depots, standard roadstops and single tram bits can only be entered from one direction */
791  DiagDirection single_entry = GetTileSingleEntry(tile, type, subtype);
792  if (single_entry != INVALID_DIAGDIR && single_entry != ReverseDiagDir(dir)) return false;
793 
794  return true;
795 }
796 
808 static TrackdirBits GetDriveableTrackdirBits(TileIndex dst_tile, Trackdir src_trackdir, TransportType type, uint subtype)
809 {
810  TrackdirBits trackdirbits = TrackStatusToTrackdirBits(GetTileTrackStatus(dst_tile, type, subtype));
811 
812  if (trackdirbits == 0 && type == TRANSPORT_ROAD && HasBit(subtype, ROADTYPE_TRAM)) {
813  /* GetTileTrackStatus() returns 0 for single tram bits.
814  * As we cannot change it there (easily) without breaking something, change it here */
815  switch (GetSingleTramBit(dst_tile)) {
816  case DIAGDIR_NE:
817  case DIAGDIR_SW:
818  trackdirbits = TRACKDIR_BIT_X_NE | TRACKDIR_BIT_X_SW;
819  break;
820 
821  case DIAGDIR_NW:
822  case DIAGDIR_SE:
823  trackdirbits = TRACKDIR_BIT_Y_NW | TRACKDIR_BIT_Y_SE;
824  break;
825 
826  default: break;
827  }
828  }
829 
830  DEBUG(npf, 4, "Next node: (%d, %d) [%d], possible trackdirs: 0x%X", TileX(dst_tile), TileY(dst_tile), dst_tile, trackdirbits);
831 
832  /* Select only trackdirs we can reach from our current trackdir */
833  trackdirbits &= TrackdirReachesTrackdirs(src_trackdir);
834 
835  /* Filter out trackdirs that would make 90 deg turns for trains */
836  if (_settings_game.pf.forbid_90_deg && (type == TRANSPORT_RAIL || type == TRANSPORT_WATER)) trackdirbits &= ~TrackdirCrossesTrackdirs(src_trackdir);
837 
838  DEBUG(npf, 6, "After filtering: (%d, %d), possible trackdirs: 0x%X", TileX(dst_tile), TileY(dst_tile), trackdirbits);
839 
840  return trackdirbits;
841 }
842 
843 
844 /* Will just follow the results of GetTileTrackStatus concerning where we can
845  * go and where not. Uses AyStar.user_data[NPF_TYPE] as the transport type and
846  * an argument to GetTileTrackStatus. Will skip tunnels, meaning that the
847  * entry and exit are neighbours. Will fill
848  * AyStarNode.user_data[NPF_TRACKDIR_CHOICE] with an appropriate value, and
849  * copy AyStarNode.user_data[NPF_NODE_FLAGS] from the parent */
850 static void NPFFollowTrack(AyStar *aystar, OpenListNode *current)
851 {
852  /* We leave src_tile on track src_trackdir in direction src_exitdir */
853  Trackdir src_trackdir = current->path.node.direction;
854  TileIndex src_tile = current->path.node.tile;
855  DiagDirection src_exitdir = TrackdirToExitdir(src_trackdir);
856 
857  /* Is src_tile valid, and can be used?
858  * When choosing track on a junction src_tile is the tile neighboured to the junction wrt. exitdir.
859  * 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. */
860  bool ignore_src_tile = (current->path.parent == NULL && NPFGetFlag(&current->path.node, NPF_FLAG_IGNORE_START_TILE));
861 
862  /* Information about the vehicle: TransportType (road/rail/water) and SubType (compatible rail/road types) */
863  TransportType type = (TransportType)aystar->user_data[NPF_TYPE];
864  uint subtype = aystar->user_data[NPF_SUB_TYPE];
865 
866  /* Initialize to 0, so we can jump out (return) somewhere an have no neighbours */
867  aystar->num_neighbours = 0;
868  DEBUG(npf, 4, "Expanding: (%d, %d, %d) [%d]", TileX(src_tile), TileY(src_tile), src_trackdir, src_tile);
869 
870  /* We want to determine the tile we arrive, and which choices we have there */
871  TileIndex dst_tile;
872  TrackdirBits trackdirbits;
873 
874  /* Find dest tile */
875  if (ignore_src_tile) {
876  /* Do not perform any checks that involve src_tile */
877  dst_tile = src_tile + TileOffsByDiagDir(src_exitdir);
878  trackdirbits = GetDriveableTrackdirBits(dst_tile, src_trackdir, type, subtype);
879  } else if (IsTileType(src_tile, MP_TUNNELBRIDGE) && GetTunnelBridgeDirection(src_tile) == src_exitdir) {
880  /* We drive through the wormhole and arrive on the other side */
881  dst_tile = GetOtherTunnelBridgeEnd(src_tile);
882  trackdirbits = TrackdirToTrackdirBits(src_trackdir);
883  } else if (ForceReverse(src_tile, src_exitdir, type, subtype)) {
884  /* We can only reverse on this tile */
885  dst_tile = src_tile;
886  src_trackdir = ReverseTrackdir(src_trackdir);
887  trackdirbits = TrackdirToTrackdirBits(src_trackdir);
888  } else {
889  /* We leave src_tile in src_exitdir and reach dst_tile */
890  dst_tile = AddTileIndexDiffCWrap(src_tile, TileIndexDiffCByDiagDir(src_exitdir));
891 
892  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;
893 
894  if (dst_tile == INVALID_TILE) {
895  /* We cannot enter the next tile. Road vehicles can reverse, others reach dead end */
896  if (type != TRANSPORT_ROAD || HasBit(subtype, ROADTYPE_TRAM)) return;
897 
898  dst_tile = src_tile;
899  src_trackdir = ReverseTrackdir(src_trackdir);
900  }
901 
902  trackdirbits = GetDriveableTrackdirBits(dst_tile, src_trackdir, type, subtype);
903 
904  if (trackdirbits == 0) {
905  /* We cannot enter the next tile. Road vehicles can reverse, others reach dead end */
906  if (type != TRANSPORT_ROAD || HasBit(subtype, ROADTYPE_TRAM)) return;
907 
908  dst_tile = src_tile;
909  src_trackdir = ReverseTrackdir(src_trackdir);
910 
911  trackdirbits = GetDriveableTrackdirBits(dst_tile, src_trackdir, type, subtype);
912  }
913  }
914 
915  if (NPFGetFlag(&current->path.node, NPF_FLAG_IGNORE_RESERVED)) {
916  /* Mask out any reserved tracks. */
917  TrackBits reserved = GetReservedTrackbits(dst_tile);
918  trackdirbits &= ~TrackBitsToTrackdirBits(reserved);
919 
920  Track t;
921  FOR_EACH_SET_TRACK(t, TrackdirBitsToTrackBits(trackdirbits)) {
922  if (TracksOverlap(reserved | TrackToTrackBits(t))) trackdirbits &= ~TrackToTrackdirBits(t);
923  }
924  }
925 
926  /* Enumerate possible track */
927  uint i = 0;
928  while (trackdirbits != 0) {
929  Trackdir dst_trackdir = RemoveFirstTrackdir(&trackdirbits);
930  DEBUG(npf, 5, "Expanded into trackdir: %d, remaining trackdirs: 0x%X", dst_trackdir, trackdirbits);
931 
932  /* Tile with signals? */
933  if (IsTileType(dst_tile, MP_RAILWAY) && GetRailTileType(dst_tile) == RAIL_TILE_SIGNALS) {
934  if (HasSignalOnTrackdir(dst_tile, ReverseTrackdir(dst_trackdir)) && !HasSignalOnTrackdir(dst_tile, dst_trackdir) && IsOnewaySignal(dst_tile, TrackdirToTrack(dst_trackdir))) {
935  /* If there's a one-way signal not pointing towards us, stop going in this direction. */
936  break;
937  }
938  }
939  {
940  /* We've found ourselves a neighbour :-) */
941  AyStarNode *neighbour = &aystar->neighbours[i];
942  neighbour->tile = dst_tile;
943  neighbour->direction = dst_trackdir;
944  /* Save user data */
945  neighbour->user_data[NPF_NODE_FLAGS] = current->path.node.user_data[NPF_NODE_FLAGS];
946  NPFFillTrackdirChoice(neighbour, current);
947  }
948  i++;
949  }
950  aystar->num_neighbours = i;
951 }
952 
953 /*
954  * Plan a route to the specified target (which is checked by target_proc),
955  * from start1 and if not NULL, from start2 as well. The type of transport we
956  * are checking is in type. reverse_penalty is applied to all routes that
957  * originate from the second start node.
958  * When we are looking for one specific target (optionally multiple tiles), we
959  * should use a good heuristic to perform aystar search. When we search for
960  * multiple targets that are spread around, we should perform a breadth first
961  * search by specifiying CalcZero as our heuristic.
962  */
963 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)
964 {
965  int r;
966  NPFFoundTargetData result;
967 
968  /* Initialize procs */
969  _npf_aystar.CalculateH = heuristic_proc;
970  _npf_aystar.EndNodeCheck = target_proc;
971  _npf_aystar.FoundEndNode = NPFSaveTargetData;
972  _npf_aystar.GetNeighbours = NPFFollowTrack;
973  switch (type) {
974  default: NOT_REACHED();
975  case TRANSPORT_RAIL: _npf_aystar.CalculateG = NPFRailPathCost; break;
976  case TRANSPORT_ROAD: _npf_aystar.CalculateG = NPFRoadPathCost; break;
977  case TRANSPORT_WATER: _npf_aystar.CalculateG = NPFWaterPathCost; break;
978  }
979 
980  /* Initialize Start Node(s) */
981  start1->user_data[NPF_TRACKDIR_CHOICE] = INVALID_TRACKDIR;
982  start1->user_data[NPF_NODE_FLAGS] = 0;
983  NPFSetFlag(start1, NPF_FLAG_IGNORE_START_TILE, ignore_start_tile1);
984  _npf_aystar.AddStartNode(start1, 0);
985  if (start2 != NULL) {
986  start2->user_data[NPF_TRACKDIR_CHOICE] = INVALID_TRACKDIR;
987  start2->user_data[NPF_NODE_FLAGS] = 0;
988  NPFSetFlag(start2, NPF_FLAG_IGNORE_START_TILE, ignore_start_tile2);
989  NPFSetFlag(start2, NPF_FLAG_REVERSE, true);
990  _npf_aystar.AddStartNode(start2, reverse_penalty);
991  }
992 
993  /* Initialize result */
994  result.best_bird_dist = UINT_MAX;
995  result.best_path_dist = UINT_MAX;
997  result.node.tile = INVALID_TILE;
998  result.res_okay = false;
999  _npf_aystar.user_path = &result;
1000 
1001  /* Initialize target */
1002  _npf_aystar.user_target = target;
1003 
1004  /* Initialize user_data */
1005  _npf_aystar.user_data[NPF_TYPE] = type;
1006  _npf_aystar.user_data[NPF_SUB_TYPE] = sub_type;
1007  _npf_aystar.user_data[NPF_OWNER] = owner;
1008  _npf_aystar.user_data[NPF_RAILTYPES] = railtypes;
1009 
1010  /* GO! */
1011  r = _npf_aystar.Main();
1012  assert(r != AYSTAR_STILL_BUSY);
1013 
1014  if (result.best_bird_dist != 0) {
1015  if (target != NULL) {
1016  DEBUG(npf, 1, "Could not find route to tile 0x%X from 0x%X.", target->dest_coords, start1->tile);
1017  } else {
1018  /* Assumption: target == NULL, so we are looking for a depot */
1019  DEBUG(npf, 1, "Could not find route to a depot from tile 0x%X.", start1->tile);
1020  }
1021 
1022  }
1023  return result;
1024 }
1025 
1026 /* Will search as below, but with two start nodes, the second being the
1027  * reverse. Look at the NPF_FLAG_REVERSE flag in the result node to see which
1028  * direction was taken (NPFGetFlag(result.node, NPF_FLAG_REVERSE)) */
1029 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)
1030 {
1031  AyStarNode start1;
1032  AyStarNode start2;
1033 
1034  start1.tile = tile1;
1035  start2.tile = tile2;
1036  /* We set this in case the target is also the start tile, we will just
1037  * return a not found then */
1038  start1.user_data[NPF_TRACKDIR_CHOICE] = INVALID_TRACKDIR;
1039  start1.direction = trackdir1;
1040  start2.direction = trackdir2;
1041  start2.user_data[NPF_TRACKDIR_CHOICE] = INVALID_TRACKDIR;
1042 
1043  return NPFRouteInternal(&start1, ignore_start_tile1, (IsValidTile(tile2) ? &start2 : NULL), ignore_start_tile2, target, NPFFindStationOrTile, NPFCalcStationOrTileHeuristic, type, sub_type, owner, railtypes, 0);
1044 }
1045 
1046 /* Will search from the given tile and direction, for a route to the given
1047  * station for the given transport type. See the declaration of
1048  * NPFFoundTargetData above for the meaning of the result. */
1049 static NPFFoundTargetData NPFRouteToStationOrTile(TileIndex tile, Trackdir trackdir, bool ignore_start_tile, NPFFindStationOrTileData *target, TransportType type, uint sub_type, Owner owner, RailTypes railtypes)
1050 {
1051  return NPFRouteToStationOrTileTwoWay(tile, trackdir, ignore_start_tile, INVALID_TILE, INVALID_TRACKDIR, false, target, type, sub_type, owner, railtypes);
1052 }
1053 
1054 /* Search using breadth first. Good for little track choice and inaccurate
1055  * heuristic, such as railway/road with two start nodes, the second being the reverse. Call
1056  * NPFGetFlag(result.node, NPF_FLAG_REVERSE) to see from which node the path
1057  * originated. All paths from the second node will have the given
1058  * reverse_penalty applied (NPF_TILE_LENGTH is the equivalent of one full
1059  * tile).
1060  */
1061 static NPFFoundTargetData NPFRouteToDepotBreadthFirstTwoWay(TileIndex tile1, Trackdir trackdir1, bool ignore_start_tile1, TileIndex tile2, Trackdir trackdir2, bool ignore_start_tile2, NPFFindStationOrTileData *target, TransportType type, uint sub_type, Owner owner, RailTypes railtypes, uint reverse_penalty)
1062 {
1063  AyStarNode start1;
1064  AyStarNode start2;
1065 
1066  start1.tile = tile1;
1067  start2.tile = tile2;
1068  /* We set this in case the target is also the start tile, we will just
1069  * return a not found then */
1070  start1.user_data[NPF_TRACKDIR_CHOICE] = INVALID_TRACKDIR;
1071  start1.direction = trackdir1;
1072  start2.direction = trackdir2;
1073  start2.user_data[NPF_TRACKDIR_CHOICE] = INVALID_TRACKDIR;
1074 
1075  /* perform a breadth first search. Target is NULL,
1076  * since we are just looking for any depot...*/
1077  return NPFRouteInternal(&start1, ignore_start_tile1, (IsValidTile(tile2) ? &start2 : NULL), ignore_start_tile2, target, NPFFindDepot, NPFCalcZero, type, sub_type, owner, railtypes, reverse_penalty);
1078 }
1079 
1080 void InitializeNPF()
1081 {
1082  static bool first_init = true;
1083  if (first_init) {
1084  first_init = false;
1085  _npf_aystar.Init(NPFHash, NPF_HASH_SIZE);
1086  } else {
1087  _npf_aystar.Clear();
1088  }
1089  _npf_aystar.loops_per_tick = 0;
1090  _npf_aystar.max_path_cost = 0;
1091  //_npf_aystar.max_search_nodes = 0;
1092  /* We will limit the number of nodes for now, until we have a better
1093  * solution to really fix performance */
1095 }
1096 
1097 static void NPFFillWithOrderData(NPFFindStationOrTileData *fstd, const Vehicle *v, bool reserve_path = false)
1098 {
1099  /* Ships don't really reach their stations, but the tile in front. So don't
1100  * save the station id for ships. For roadvehs we don't store it either,
1101  * because multistop depends on vehicles actually reaching the exact
1102  * dest_tile, not just any stop of that station.
1103  * So only for train orders to stations we fill fstd->station_index, for all
1104  * others only dest_coords */
1105  if (v->type != VEH_SHIP && (v->current_order.IsType(OT_GOTO_STATION) || v->current_order.IsType(OT_GOTO_WAYPOINT))) {
1106  assert(v->IsGroundVehicle());
1108  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);
1110  /* Let's take the closest tile of the station as our target for vehicles */
1112  } else {
1113  fstd->dest_coords = v->dest_tile;
1114  fstd->station_index = INVALID_STATION;
1115  }
1116  fstd->reserve_path = reserve_path;
1117  fstd->v = v;
1118 }
1119 
1120 /*** Road vehicles ***/
1121 
1123 {
1124  Trackdir trackdir = v->GetVehicleTrackdir();
1125 
1126  NPFFoundTargetData ftd = NPFRouteToDepotBreadthFirstTwoWay(v->tile, trackdir, false, v->tile, ReverseTrackdir(trackdir), false, NULL, TRANSPORT_ROAD, v->compatible_roadtypes, v->owner, INVALID_RAILTYPES, 0);
1127 
1128  if (ftd.best_bird_dist != 0) return FindDepotData();
1129 
1130  /* Found target */
1131  /* Our caller expects a number of tiles, so we just approximate that
1132  * number by this. It might not be completely what we want, but it will
1133  * work for now :-) We can possibly change this when the old pathfinder
1134  * is removed. */
1135  return FindDepotData(ftd.node.tile, ftd.best_path_dist);
1136 }
1137 
1138 Trackdir NPFRoadVehicleChooseTrack(const RoadVehicle *v, TileIndex tile, DiagDirection enterdir, TrackdirBits trackdirs, bool &path_found)
1139 {
1141 
1142  NPFFillWithOrderData(&fstd, v);
1143  Trackdir trackdir = DiagDirToDiagTrackdir(enterdir);
1144 
1145  NPFFoundTargetData ftd = NPFRouteToStationOrTile(tile - TileOffsByDiagDir(enterdir), trackdir, true, &fstd, TRANSPORT_ROAD, v->compatible_roadtypes, v->owner, INVALID_RAILTYPES);
1146  if (ftd.best_trackdir == INVALID_TRACKDIR) {
1147  /* We are already at our target. Just do something
1148  * @todo: maybe display error?
1149  * @todo: go straight ahead if possible? */
1150  path_found = true;
1151  return (Trackdir)FindFirstBit2x64(trackdirs);
1152  }
1153 
1154  /* If ftd.best_bird_dist is 0, we found our target and ftd.best_trackdir contains
1155  * the direction we need to take to get there, if ftd.best_bird_dist is not 0,
1156  * we did not find our target, but ftd.best_trackdir contains the direction leading
1157  * to the tile closest to our target. */
1158  path_found = (ftd.best_bird_dist == 0);
1159  return ftd.best_trackdir;
1160 }
1161 
1162 /*** Ships ***/
1163 
1164 Track NPFShipChooseTrack(const Ship *v, TileIndex tile, DiagDirection enterdir, TrackBits tracks, bool &path_found)
1165 {
1167  Trackdir trackdir = v->GetVehicleTrackdir();
1168  assert(trackdir != INVALID_TRACKDIR); // Check that we are not in a depot
1169 
1170  NPFFillWithOrderData(&fstd, v);
1171 
1172  NPFFoundTargetData ftd = NPFRouteToStationOrTile(tile - TileOffsByDiagDir(enterdir), trackdir, true, &fstd, TRANSPORT_WATER, 0, v->owner, INVALID_RAILTYPES);
1173 
1174  /* If ftd.best_bird_dist is 0, we found our target and ftd.best_trackdir contains
1175  * the direction we need to take to get there, if ftd.best_bird_dist is not 0,
1176  * we did not find our target, but ftd.best_trackdir contains the direction leading
1177  * to the tile closest to our target. */
1178  path_found = (ftd.best_bird_dist == 0);
1179  if (ftd.best_trackdir == 0xff) return INVALID_TRACK;
1180  return TrackdirToTrack(ftd.best_trackdir);
1181 }
1182 
1184 {
1186  NPFFoundTargetData ftd;
1187 
1188  NPFFillWithOrderData(&fstd, v);
1189 
1190  Trackdir trackdir = v->GetVehicleTrackdir();
1191  Trackdir trackdir_rev = ReverseTrackdir(trackdir);
1192  assert(trackdir != INVALID_TRACKDIR);
1193  assert(trackdir_rev != INVALID_TRACKDIR);
1194 
1195  ftd = NPFRouteToStationOrTileTwoWay(v->tile, trackdir, false, v->tile, trackdir_rev, false, &fstd, TRANSPORT_WATER, 0, v->owner, INVALID_RAILTYPES);
1196  /* If we didn't find anything, just keep on going straight ahead, otherwise take the reverse flag */
1197  return ftd.best_bird_dist == 0 && NPFGetFlag(&ftd.node, NPF_FLAG_REVERSE);
1198 }
1199 
1200 /*** Trains ***/
1201 
1203 {
1204  const Train *last = v->Last();
1205  Trackdir trackdir = v->GetVehicleTrackdir();
1206  Trackdir trackdir_rev = ReverseTrackdir(last->GetVehicleTrackdir());
1208  fstd.v = v;
1209  fstd.reserve_path = false;
1210 
1211  assert(trackdir != INVALID_TRACKDIR);
1212  NPFFoundTargetData ftd = NPFRouteToDepotBreadthFirstTwoWay(v->tile, trackdir, false, last->tile, trackdir_rev, false, &fstd, TRANSPORT_RAIL, 0, v->owner, v->compatible_railtypes, NPF_INFINITE_PENALTY);
1213  if (ftd.best_bird_dist != 0) return FindDepotData();
1214 
1215  /* Found target */
1216  /* Our caller expects a number of tiles, so we just approximate that
1217  * number by this. It might not be completely what we want, but it will
1218  * work for now :-) We can possibly change this when the old pathfinder
1219  * is removed. */
1220  return FindDepotData(ftd.node.tile, ftd.best_path_dist, NPFGetFlag(&ftd.node, NPF_FLAG_REVERSE));
1221 }
1222 
1223 bool NPFTrainFindNearestSafeTile(const Train *v, TileIndex tile, Trackdir trackdir, bool override_railtype)
1224 {
1225  assert(v->type == VEH_TRAIN);
1226 
1228  fstd.v = v;
1229  fstd.reserve_path = true;
1230 
1231  AyStarNode start1;
1232  start1.tile = tile;
1233  /* We set this in case the target is also the start tile, we will just
1234  * return a not found then */
1235  start1.user_data[NPF_TRACKDIR_CHOICE] = INVALID_TRACKDIR;
1236  start1.direction = trackdir;
1237  NPFSetFlag(&start1, NPF_FLAG_IGNORE_RESERVED, true);
1238 
1239  RailTypes railtypes = v->compatible_railtypes;
1240  if (override_railtype) railtypes |= GetRailTypeInfo(v->railtype)->compatible_railtypes;
1241 
1242  /* perform a breadth first search. Target is NULL,
1243  * since we are just looking for any safe tile...*/
1244  return NPFRouteInternal(&start1, true, NULL, false, &fstd, NPFFindSafeTile, NPFCalcZero, TRANSPORT_RAIL, 0, v->owner, railtypes, 0).res_okay;
1245 }
1246 
1248 {
1250  NPFFoundTargetData ftd;
1251  const Train *last = v->Last();
1252 
1253  NPFFillWithOrderData(&fstd, v);
1254 
1255  Trackdir trackdir = v->GetVehicleTrackdir();
1256  Trackdir trackdir_rev = ReverseTrackdir(last->GetVehicleTrackdir());
1257  assert(trackdir != INVALID_TRACKDIR);
1258  assert(trackdir_rev != INVALID_TRACKDIR);
1259 
1260  ftd = NPFRouteToStationOrTileTwoWay(v->tile, trackdir, false, last->tile, trackdir_rev, false, &fstd, TRANSPORT_RAIL, 0, v->owner, v->compatible_railtypes);
1261  /* If we didn't find anything, just keep on going straight ahead, otherwise take the reverse flag */
1262  return ftd.best_bird_dist == 0 && NPFGetFlag(&ftd.node, NPF_FLAG_REVERSE);
1263 }
1264 
1265 Track NPFTrainChooseTrack(const Train *v, TileIndex tile, DiagDirection enterdir, TrackBits tracks, bool &path_found, bool reserve_track, struct PBSTileInfo *target)
1266 {
1268  NPFFillWithOrderData(&fstd, v, reserve_track);
1269 
1270  PBSTileInfo origin = FollowTrainReservation(v);
1271  assert(IsValidTrackdir(origin.trackdir));
1272 
1273  NPFFoundTargetData ftd = NPFRouteToStationOrTile(origin.tile, origin.trackdir, true, &fstd, TRANSPORT_RAIL, 0, v->owner, v->compatible_railtypes);
1274 
1275  if (target != NULL) {
1276  target->tile = ftd.node.tile;
1277  target->trackdir = (Trackdir)ftd.node.direction;
1278  target->okay = ftd.res_okay;
1279  }
1280 
1281  if (ftd.best_trackdir == INVALID_TRACKDIR) {
1282  /* We are already at our target. Just do something
1283  * @todo maybe display error?
1284  * @todo: go straight ahead if possible? */
1285  path_found = true;
1286  return FindFirstTrack(tracks);
1287  }
1288 
1289  /* If ftd.best_bird_dist is 0, we found our target and ftd.best_trackdir contains
1290  * the direction we need to take to get there, if ftd.best_bird_dist is not 0,
1291  * we did not find our target, but ftd.best_trackdir contains the direction leading
1292  * to the tile closest to our target. */
1293  path_found = (ftd.best_bird_dist == 0);
1294  /* Discard enterdir information, making it a normal track */
1295  return TrackdirToTrack(ftd.best_trackdir);
1296 }