src/pathfinder/yapf/yapf.h

   1 /* $Id$ */
   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
  10 /** @file yapf.h Entry point for OpenTTD to YAPF. */
  11
  12 #ifndef YAPF_H
  13 #define YAPF_H
  14
  15 #include "../../direction_type.h"
  16 #include "../../track_type.h"
  17 #include "../../vehicle_type.h"
  18 #include "../types.h"
  19
  20 /** Length (penalty) of one tile with YAPF */
  21 static const int YAPF_TILE_LENGTH = 100;
  22
  23 /** Length (penalty) of a corner with YAPF */
  24 static const int YAPF_TILE_CORNER_LENGTH = 71;
  25
  26 /**
  27  * This penalty is the equivalent of "infinite", which means that paths that
  28  * get this penalty will be chosen, but only if there is no other route
  29  * without it. Be careful with not applying this penalty to often, or the
  30  * total path cost might overflow..
  31  */
  32 static const int YAPF_INFINITE_PENALTY = 1000 * YAPF_TILE_LENGTH;
  33
  34 /**
  35  * Finds the best path for given ship using YAPF.
  36  * @param v        the ship that needs to find a path
  37  * @param tile     the tile to find the path from (should be next tile the ship is about to enter)
  38  * @param enterdir diagonal direction which the ship will enter this new tile from
  39  * @param trackdirs available trackdirs on the new tile (to choose from)
  40  * @param path_found [out] Whether a path has been found (true) or has been guessed (false)
  41  * @return         the best trackdir for next turn or INVALID_TRACKDIR if the path could not be found
  42  */
  43 Trackdir YapfShipChooseTrack(const Ship *v, TileIndex tile, DiagDirection enterdir, TrackdirBits trackdirs, bool &path_found);
  44
  45 /**
  46  * Returns true if it is better to reverse the ship before leaving depot using YAPF.
  47  * @param v the ship leaving the depot
  48  * @return true if reversing is better
  49  */
  50 bool YapfShipCheckReverse(const Ship *v);
  51
  52 /**
  53  * Find the nearest depot to a ship
  54  * @param v the ship looking for a depot
  55  * @param max_distance maximum allowed distance, or 0 for any distance
  56  * @return the tile of the nearest depot
  57  */
  58 TileIndex YapfShipFindNearestDepot (const Ship *v, uint max_distance);
  59
  60 /**
  61  * Finds the best path for given road vehicle using YAPF.
  62  * @param v         the RV that needs to find a path
  63  * @param tile      the tile to find the path from (should be next tile the RV is about to enter)
  64  * @param enterdir  diagonal direction which the RV will enter this new tile from
  65  * @param trackdirs available trackdirs on the new tile (to choose from)
  66  * @param path_found [out] Whether a path has been found (true) or has been guessed (false)
  67  * @return          the best trackdir for next turn or INVALID_TRACKDIR if the path could not be found
  68  */
  69 Trackdir YapfRoadVehicleChooseTrack(const RoadVehicle *v, TileIndex tile, DiagDirection enterdir, TrackdirBits trackdirs, bool &path_found);
  70
  71 /**
  72  * Finds the best path for given train using YAPF.
  73  * @param v        the train that needs to find a path
  74  * @param origin   the end of the current reservation
  75  * @param reserve_track indicates whether YAPF should try to reserve the found path
  76  * @param target   [out] the target tile of the reservation, free is set to true if path was reserved
  77  * @return         the best trackdir for next turn
  78  */
  79 Trackdir YapfTrainChooseTrack(const Train *v, const RailPathPos &origin, bool reserve_track, struct PFResult *target);
  80
  81 /**
  82  * Used when user sends road vehicle to the nearest depot or if road vehicle needs servicing using YAPF.
  83  * @param v            vehicle that needs to go to some depot
  84  * @param max_penalty  max distance (in pathfinder penalty) from the current vehicle position
  85  *                     (used also as optimization - the pathfinder can stop path finding if max_penalty
  86  *                     was reached and no depot was seen)
  87  * @return             depot tile found, or INVALID_TILE if no depot was found
  88  */
  89 TileIndex YapfRoadVehicleFindNearestDepot(const RoadVehicle *v, uint max_penalty);
  90
  91 /**
  92  * Used when user sends train to the nearest depot or if train needs servicing using YAPF.
  93  * @param v            train that needs to go to some depot
  94  * @param origin       the end of the current reservation
  95  * @param max_distance max distance (int pathfinder penalty) from the current train position
  96  *                     (used also as optimization - the pathfinder can stop path finding if max_penalty
  97  *                     was reached and no depot was seen)
  98  * @param res          pointer to store the data about the depot
  99  * @return             whether a depot was found
 100  */
 101 bool YapfTrainFindNearestDepot (const Train *v, const RailPathPos &origin, uint max_distance, FindDepotData *res);
 102
 103 /**
 104  * Returns true if it is better to reverse the train before leaving station using YAPF.
 105  * @param v the train leaving the station
 106  * @return true if reversing is better
 107  */
 108 bool YapfTrainCheckReverse(const Train *v);
 109
 110 /**
 111  * Try to extend the reserved path of a train to the nearest safe tile using YAPF.
 112  *
 113  * @param v    The train that needs to find a safe tile.
 114  * @param pos  Last position of the current reserved path.
 115  * @param override_railtype Should all physically compatible railtypes be searched, even if the vehicle can't run on them on its own?
 116  * @return True if the path could be extended to a safe tile.
 117  */
 118 bool YapfTrainFindNearestSafeTile(const Train *v, const RailPathPos &pos, bool override_railtype);
 119
 120 /**
 121  * Use this function to notify YAPF that track layout (or signal configuration) has change.
 122  */
 123 void YapfNotifyTrackLayoutChange (void);
 124
 125 #endif /* YAPF_H */