OpenTTD
aystar.h
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1 /* $Id: aystar.h 24900 2013-01-08 22:46:42Z planetmaker $ */
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 
18 #ifndef AYSTAR_H
19 #define AYSTAR_H
20 
21 #include "queue.h"
22 #include "../../tile_type.h"
23 #include "../../track_type.h"
24 
25 //#define AYSTAR_DEBUG
26 
35 };
36 
37 static const int AYSTAR_INVALID_NODE = -1;
38 
40 struct AyStarNode {
41  TileIndex tile;
42  Trackdir direction;
43  uint user_data[2];
44 };
45 
47 struct PathNode {
48  AyStarNode node;
50 };
51 
57 struct OpenListNode {
58  int g;
59  PathNode path;
60 };
61 
62 struct AyStar;
63 
78 typedef int32 AyStar_EndNodeCheck(AyStar *aystar, OpenListNode *current);
79 
86 typedef int32 AyStar_CalculateG(AyStar *aystar, AyStarNode *current, OpenListNode *parent);
87 
93 typedef int32 AyStar_CalculateH(AyStar *aystar, AyStarNode *current, OpenListNode *parent);
94 
100 typedef void AyStar_GetNeighbours(AyStar *aystar, OpenListNode *current);
101 
106 typedef void AyStar_FoundEndNode(AyStar *aystar, OpenListNode *current);
107 
116 struct AyStar {
117 /* These fields should be filled before initing the AyStar, but not changed
118  * afterwards (except for user_data and user_path)! (free and init again to change them) */
119 
120  /* These should point to the application specific routines that do the
121  * actual work */
122  AyStar_CalculateG *CalculateG;
123  AyStar_CalculateH *CalculateH;
124  AyStar_GetNeighbours *GetNeighbours;
125  AyStar_EndNodeCheck *EndNodeCheck;
126  AyStar_FoundEndNode *FoundEndNode;
127 
128  /* These are completely untouched by AyStar, they can be accessed by
129  * the application specific routines to input and output data.
130  * user_path should typically contain data about the resulting path
131  * afterwards, user_target should typically contain information about
132  * what you where looking for, and user_data can contain just about
133  * everything */
134  void *user_path;
135  void *user_target;
136  uint user_data[10];
137 
141 
142  /* These should be filled with the neighbours of a tile by
143  * GetNeighbours */
144  AyStarNode neighbours[12];
145  byte num_neighbours;
146 
147  void Init(Hash_HashProc hash, uint num_buckets);
148 
149  /* These will contain the methods for manipulating the AyStar. Only
150  * Main() should be called externally */
151  void AddStartNode(AyStarNode *start_node, uint g);
152  int Main();
153  int Loop();
154  void Free();
155  void Clear();
156  void CheckTile(AyStarNode *current, OpenListNode *parent);
157 
158 protected:
162 
163  void OpenListAdd(PathNode *parent, const AyStarNode *node, int f, int g);
166 
167  void ClosedListAdd(const PathNode *node);
168  PathNode *ClosedListIsInList(const AyStarNode *node);
169 };
170 
171 #endif /* AYSTAR_H */