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 */
81 /* Special epfile values. [HGM] positive values are non-reversible moves! */
82 #define EP_NONE (-4) /* [HGM] Tricky! order matters: */
83 #define EP_UNKNOWN (-1) /* >= EP_UNKNOWN spils rep-draw */
84 #define EP_CAPTURE (-2) /* <= EP_NONE is reversible move */
85 #define EP_PAWN_MOVE (-3)
86 #define EP_REP_DRAW (-15)
87 #define EP_RULE_DRAW (-14)
88 #define EP_INSUF_DRAW (-13)
89 #define EP_DRAWS (-10)
90 #define EP_BEROLIN_A 16 /* [HGM] berolina: add to file if pawn to be taken of a-side of e.p.file */
91 #define EP_CHECKMATE 100 /* [HGM] verify: record mates in epStatus for easy claim verification */
92 #define EP_STALEMATE -16
94 /* Call callback once for each pseudo-legal move in the given
95 position, except castling moves. A move is pseudo-legal if it is
96 legal, or if it would be legal except that it leaves the king in
97 check. In the arguments, epfile is EP_NONE if the previous move
98 was not a double pawn push, or the file 0..7 if it was, or
99 EP_UNKNOWN if we don't know and want to allow all e.p. captures.
100 Promotion moves generated are to Queen only.
102 extern void GenPseudoLegal P((Board board, int flags, int epfile,
103 MoveCallback callback, VOIDSTAR closure));
105 /* Like GenPseudoLegal, but include castling moves and (unless
106 F_IGNORE_CHECK is set in the flags) omit moves that would leave the
107 king in check. The CASTLE_OK flags are true if castling is not yet
108 ruled out by a move of the king or rook. Return TRUE if the player
109 on move is currently in check and F_IGNORE_CHECK is not set.
111 extern int GenLegal P((Board board, int flags, int epfile,
112 char castlingRights[], /* [HGM] */
113 MoveCallback callback, VOIDSTAR closure));
115 /* If the player on move were to move from (rf, ff) to (rt, ft), would
116 he leave himself in check? Or if rf == -1, is the player on move
117 in check now? enPassant must be TRUE if the indicated move is an
118 e.p. capture. The possibility of castling out of a check along the
119 back rank is not accounted for (i.e., we still return nonzero), as
120 this is illegal anyway. Return value is the number of times the
122 extern int CheckTest P((Board board, int flags,
123 int rf, int ff, int rt, int ft, int enPassant));
125 /* Is a move from (rf, ff) to (rt, ft) legal for the player whom the
126 flags say is on move? Other arguments as in GenPseudoLegal.
127 Returns the type of move made, taking promoChar into account. */
128 extern ChessMove LegalityTest P((Board board, int flags, int epfile,
129 char castlingRights[], /* [HGM] */
130 int rf, int ff, int rt, int ft,
135 #define MT_CHECKMATE 2
136 #define MT_STALEMATE 3
138 /* Return MT_NONE, MT_CHECK, MT_CHECKMATE, or MT_STALEMATE */
139 extern int MateTest P((Board board, int flags, int epfile,
140 char castlingRights[])); /* [HGM] */
144 ChessSquare pieceIn; /* EmptySquare if unknown */
145 int rfIn, ffIn, rtIn, ftIn; /* -1 if unknown */
146 int promoCharIn; /* NULLCHAR if unknown */
147 /* Output data for matched move */
151 int promoChar; /* 'q' if a promotion and promoCharIn was NULLCHAR */
152 int count; /* Number of possibilities found */
153 } DisambiguateClosure;
155 /* Disambiguate a partially-known move */
156 void Disambiguate P((Board board, int flags, int epfile,
157 DisambiguateClosure *closure));
160 /* Convert coordinates to normal algebraic notation.
161 promoChar must be NULLCHAR or '.' if not a promotion.
163 ChessMove CoordsToAlgebraic P((Board board, int flags, int epfile,
164 int rf, int ff, int rt, int ft,
165 int promoChar, char out[MOVE_LEN]));