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 0x200
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)
92 #define EP_BEROLIN_A 16 /* [HGM] berolina: add to file if pawn to be taken of a-side of e.p.file */
93 #define EP_CHECKMATE 100 /* [HGM] verify: record mates in epStatus for easy claim verification */
94 #define EP_STALEMATE -16
96 /* Call callback once for each pseudo-legal move in the given
97 position, except castling moves. A move is pseudo-legal if it is
98 legal, or if it would be legal except that it leaves the king in
99 check. In the arguments, epfile is EP_NONE if the previous move
100 was not a double pawn push, or the file 0..7 if it was, or
101 EP_UNKNOWN if we don't know and want to allow all e.p. captures.
102 Promotion moves generated are to Queen only.
104 extern void GenPseudoLegal P((Board board, int flags, int epfile,
105 MoveCallback callback, VOIDSTAR closure));
107 /* Like GenPseudoLegal, but include castling moves and (unless
108 F_IGNORE_CHECK is set in the flags) omit moves that would leave the
109 king in check. The CASTLE_OK flags are true if castling is not yet
110 ruled out by a move of the king or rook. Return TRUE if the player
111 on move is currently in check and F_IGNORE_CHECK is not set.
113 extern int GenLegal P((Board board, int flags, int epfile,
114 char castlingRights[], /* [HGM] */
115 MoveCallback callback, VOIDSTAR closure));
117 /* If the player on move were to move from (rf, ff) to (rt, ft), would
118 he leave himself in check? Or if rf == -1, is the player on move
119 in check now? enPassant must be TRUE if the indicated move is an
120 e.p. capture. The possibility of castling out of a check along the
121 back rank is not accounted for (i.e., we still return nonzero), as
122 this is illegal anyway. Return value is the number of times the
124 extern int CheckTest P((Board board, int flags,
125 int rf, int ff, int rt, int ft, int enPassant));
127 /* Is a move from (rf, ff) to (rt, ft) legal for the player whom the
128 flags say is on move? Other arguments as in GenPseudoLegal.
129 Returns the type of move made, taking promoChar into account. */
130 extern ChessMove LegalityTest P((Board board, int flags, int epfile,
131 char castlingRights[], /* [HGM] */
132 int rf, int ff, int rt, int ft,
137 #define MT_CHECKMATE 2
138 #define MT_STALEMATE 3
139 #define MT_STAINMATE 4 /* [HGM] xq: for games where being stalemated counts as a loss */
140 #define MT_STEALMATE 5 /* [HGM] losers: for games where being stalemated counts as a win */
141 #define MT_TRICKMATE 6 /* [HGM] losers: for games where being checkmated counts as a win */
142 #define MT_BARE 7 /* [HGM] shatranj: for games where having bare king loses */
143 #define MT_DRAW 8 /* [HGM] shatranj: other draws */
144 #define MT_NOKING 9 /* [HGM] atomic: for games lost through king capture */
146 /* Return MT_NONE, MT_CHECK, MT_CHECKMATE, or MT_STALEMATE */
147 extern int MateTest P((Board board, int flags, int epfile,
148 char castlingRights[])); /* [HGM] */
152 ChessSquare pieceIn; /* EmptySquare if unknown */
153 int rfIn, ffIn, rtIn, ftIn; /* -1 if unknown */
154 int promoCharIn; /* NULLCHAR if unknown */
155 /* Output data for matched move */
159 int promoChar; /* 'q' if a promotion and promoCharIn was NULLCHAR */
160 int count; /* Number of possibilities found */
161 } DisambiguateClosure;
163 /* Disambiguate a partially-known move */
164 void Disambiguate P((Board board, int flags, int epfile,
165 DisambiguateClosure *closure));
168 /* Convert coordinates to normal algebraic notation.
169 promoChar must be NULLCHAR or '.' if not a promotion.
171 ChessMove CoordsToAlgebraic P((Board board, int flags, int epfile,
172 int rf, int ff, int rt, int ft,
173 int promoChar, char out[MOVE_LEN]));