2 * moves.h - Move generation and checking
3 * $Id: moves.h,v 2.1 2003/10/27 19:21:00 mann Exp $
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49 *------------------------------------------------------------------------
50 ** See the file ChangeLog for a revision history. */
52 extern ChessSquare PromoPiece P((ChessMove moveType));
53 extern ChessMove PromoCharToMoveType P((int whiteOnMove, int promoChar));
54 extern char PieceToChar P((ChessSquare p));
55 extern ChessSquare CharToPiece P((int c));
56 extern int PieceToNumber P((ChessSquare p));
58 extern void CopyBoard P((Board to, Board from));
59 extern int CompareBoards P((Board board1, Board board2));
60 extern char pieceToChar[(int)EmptySquare+1];
62 typedef void (*MoveCallback) P((Board board, int flags, ChessMove kind,
63 int rf, int ff, int rt, int ft,
66 /* Values for flags arguments */
67 #define F_WHITE_ON_MOVE 1
68 #define F_WHITE_KCASTLE_OK 2
69 #define F_WHITE_QCASTLE_OK 4
70 #define F_BLACK_KCASTLE_OK 8
71 #define F_BLACK_QCASTLE_OK 16
72 #define F_ALL_CASTLE_OK (F_WHITE_KCASTLE_OK | F_WHITE_QCASTLE_OK | \
73 F_BLACK_KCASTLE_OK | F_BLACK_QCASTLE_OK)
74 #define F_IGNORE_CHECK 32
75 #define F_KRIEGSPIEL_CAPTURE 64 /* pawns can try to capture invisible pieces */
76 #define F_ATOMIC_CAPTURE 128 /* capturing piece explodes, destroying itself
77 and all non-pawns on adjacent squares;
78 destroying your own king is illegal */
79 #define F_FRC_TYPE_CASTLING 256 /* generate castlings as captures of own Rook */
80 #define F_MANDATORY_CAPTURE 0x100
82 /* Special epfile values. [HGM] positive values are non-reversible moves! */
83 #define EP_NONE (-4) /* [HGM] Tricky! order matters: */
84 #define EP_UNKNOWN (-1) /* >= EP_UNKNOWN spils rep-draw */
85 #define EP_CAPTURE (-2) /* <= EP_NONE is reversible move */
86 #define EP_PAWN_MOVE (-3)
87 #define EP_REP_DRAW (-15)
88 #define EP_RULE_DRAW (-14)
89 #define EP_INSUF_DRAW (-13)
90 #define EP_DRAWS (-10)
91 #define EP_BEROLIN_A 16 /* [HGM] berolina: add to file if pawn to be taken of a-side of e.p.file */
92 #define EP_CHECKMATE 100 /* [HGM] verify: record mates in epStatus for easy claim verification */
93 #define EP_STALEMATE -16
95 /* Call callback once for each pseudo-legal move in the given
96 position, except castling moves. A move is pseudo-legal if it is
97 legal, or if it would be legal except that it leaves the king in
98 check. In the arguments, epfile is EP_NONE if the previous move
99 was not a double pawn push, or the file 0..7 if it was, or
100 EP_UNKNOWN if we don't know and want to allow all e.p. captures.
101 Promotion moves generated are to Queen only.
103 extern void GenPseudoLegal P((Board board, int flags, int epfile,
104 MoveCallback callback, VOIDSTAR closure));
106 /* Like GenPseudoLegal, but include castling moves and (unless
107 F_IGNORE_CHECK is set in the flags) omit moves that would leave the
108 king in check. The CASTLE_OK flags are true if castling is not yet
109 ruled out by a move of the king or rook. Return TRUE if the player
110 on move is currently in check and F_IGNORE_CHECK is not set.
112 extern int GenLegal P((Board board, int flags, int epfile,
113 char castlingRights[], /* [HGM] */
114 MoveCallback callback, VOIDSTAR closure));
116 /* If the player on move were to move from (rf, ff) to (rt, ft), would
117 he leave himself in check? Or if rf == -1, is the player on move
118 in check now? enPassant must be TRUE if the indicated move is an
119 e.p. capture. The possibility of castling out of a check along the
120 back rank is not accounted for (i.e., we still return nonzero), as
121 this is illegal anyway. Return value is the number of times the
123 extern int CheckTest P((Board board, int flags,
124 int rf, int ff, int rt, int ft, int enPassant));
126 /* Is a move from (rf, ff) to (rt, ft) legal for the player whom the
127 flags say is on move? Other arguments as in GenPseudoLegal.
128 Returns the type of move made, taking promoChar into account. */
129 extern ChessMove LegalityTest P((Board board, int flags, int epfile,
130 char castlingRights[], /* [HGM] */
131 int rf, int ff, int rt, int ft,
136 #define MT_CHECKMATE 2
137 #define MT_STALEMATE 3
139 /* Return MT_NONE, MT_CHECK, MT_CHECKMATE, or MT_STALEMATE */
140 extern int MateTest P((Board board, int flags, int epfile,
141 char castlingRights[])); /* [HGM] */
145 ChessSquare pieceIn; /* EmptySquare if unknown */
146 int rfIn, ffIn, rtIn, ftIn; /* -1 if unknown */
147 int promoCharIn; /* NULLCHAR if unknown */
148 /* Output data for matched move */
152 int promoChar; /* 'q' if a promotion and promoCharIn was NULLCHAR */
153 int count; /* Number of possibilities found */
154 } DisambiguateClosure;
156 /* Disambiguate a partially-known move */
157 void Disambiguate P((Board board, int flags, int epfile,
158 DisambiguateClosure *closure));
161 /* Convert coordinates to normal algebraic notation.
162 promoChar must be NULLCHAR or '.' if not a promotion.
164 ChessMove CoordsToAlgebraic P((Board board, int flags, int epfile,
165 int rf, int ff, int rt, int ft,
166 int promoChar, char out[MOVE_LEN]));