2 * moves.c - Move generation and checking
4 * Copyright 1991 by Digital Equipment Corporation, Maynard,
7 * Enhancements Copyright 1992-2001, 2002, 2003, 2004, 2005, 2006,
8 * 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014 Free Software Foundation, Inc.
10 * Enhancements Copyright 2005 Alessandro Scotti
12 * The following terms apply to Digital Equipment Corporation's copyright
14 * ------------------------------------------------------------------------
17 * Permission to use, copy, modify, and distribute this software and its
18 * documentation for any purpose and without fee is hereby granted,
19 * provided that the above copyright notice appear in all copies and that
20 * both that copyright notice and this permission notice appear in
21 * supporting documentation, and that the name of Digital not be
22 * used in advertising or publicity pertaining to distribution of the
23 * software without specific, written prior permission.
25 * DIGITAL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
26 * ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL
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28 * ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
29 * WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
30 * ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
32 * ------------------------------------------------------------------------
34 * The following terms apply to the enhanced version of XBoard
35 * distributed by the Free Software Foundation:
36 * ------------------------------------------------------------------------
38 * GNU XBoard is free software: you can redistribute it and/or modify
39 * it under the terms of the GNU General Public License as published by
40 * the Free Software Foundation, either version 3 of the License, or (at
41 * your option) any later version.
43 * GNU XBoard is distributed in the hope that it will be useful, but
44 * WITHOUT ANY WARRANTY; without even the implied warranty of
45 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
46 * General Public License for more details.
48 * You should have received a copy of the GNU General Public License
49 * along with this program. If not, see http://www.gnu.org/licenses/. *
51 *------------------------------------------------------------------------
52 ** See the file ChangeLog for a revision history. */
61 #else /* not HAVE_STRING_H */
63 #endif /* not HAVE_STRING_H */
69 int WhitePiece P((ChessSquare));
70 int BlackPiece P((ChessSquare));
71 int SameColor P((ChessSquare, ChessSquare));
72 int PosFlags(int index);
74 extern signed char initialRights[BOARD_FILES]; /* [HGM] all rights enabled, set in InitPosition */
76 char *pieceDesc[EmptySquare];
77 char *defaultDesc[EmptySquare] = {
78 "fmWfceFifmnD", "N", "B", "R", "Q",
79 "F", "A", "BN", "RN", "W", "K",
80 "mRcpR", "N0", "BW", "RF", "gQ",
81 "", "", "QN", "", "N", "",
83 "", "", "", "", "", "",
85 "", "", "", "", "", "K"
89 WhitePiece (ChessSquare piece)
91 return (int) piece >= (int) WhitePawn && (int) piece < (int) BlackPawn;
95 BlackPiece (ChessSquare piece)
97 return (int) piece >= (int) BlackPawn && (int) piece < (int) EmptySquare;
102 SameColor (ChessSquare piece1, ChessSquare piece2)
104 return ((int) piece1 >= (int) WhitePawn && /* [HGM] can be > King ! */
105 (int) piece1 < (int) BlackPawn &&
106 (int) piece2 >= (int) WhitePawn &&
107 (int) piece2 < (int) BlackPawn)
108 || ((int) piece1 >= (int) BlackPawn &&
109 (int) piece1 < (int) EmptySquare &&
110 (int) piece2 >= (int) BlackPawn &&
111 (int) piece2 < (int) EmptySquare);
114 #define SameColor(piece1, piece2) (piece1 < EmptySquare && piece2 < EmptySquare && (piece1 < BlackPawn) == (piece2 < BlackPawn) || piece1 == DarkSquare || piece2 == DarkSquare)
117 char pieceToChar[] = {
118 'P', 'N', 'B', 'R', 'Q', 'F', 'E', 'A', 'C', 'W', 'M',
119 'O', 'H', 'I', 'J', 'G', 'D', 'V', 'L', 'S', 'U', 'K',
120 'p', 'n', 'b', 'r', 'q', 'f', 'e', 'a', 'c', 'w', 'm',
121 'o', 'h', 'i', 'j', 'g', 'd', 'v', 'l', 's', 'u', 'k',
123 char pieceNickName[EmptySquare];
126 PieceToChar (ChessSquare p)
128 if((int)p < 0 || (int)p >= (int)EmptySquare) return('x'); /* [HGM] for safety */
129 return pieceToChar[(int) p];
133 PieceToNumber (ChessSquare p) /* [HGM] holdings: count piece type, ignoring non-participating piece types */
136 ChessSquare start = (int)p >= (int)BlackPawn ? BlackPawn : WhitePawn;
138 while(start++ != p) if(pieceToChar[start-1] != '.' && pieceToChar[start-1] != '+') i++;
146 if(c == '.') return EmptySquare;
147 for(i=0; i< (int) EmptySquare; i++)
148 if(pieceNickName[i] == c) return (ChessSquare) i;
149 for(i=0; i< (int) EmptySquare; i++)
150 if(pieceToChar[i] == c) return (ChessSquare) i;
155 CopyBoard (Board to, Board from)
159 for (i = 0; i < BOARD_HEIGHT; i++)
160 for (j = 0; j < BOARD_WIDTH; j++)
161 to[i][j] = from[i][j];
162 for (j = 0; j < BOARD_FILES; j++) // [HGM] gamestate: copy castling rights and ep status
163 to[VIRGIN][j] = from[VIRGIN][j],
164 to[CASTLING][j] = from[CASTLING][j];
165 to[HOLDINGS_SET] = 0; // flag used in ICS play
169 CompareBoards (Board board1, Board board2)
173 for (i = 0; i < BOARD_HEIGHT; i++)
174 for (j = 0; j < BOARD_WIDTH; j++) {
175 if (board1[i][j] != board2[i][j])
181 char defaultName[] = "PNBRQ......................................K" // white
182 "pnbrq......................................k"; // black
183 char shogiName[] = "PNBRLS...G.++++++..........................K" // white
184 "pnbrls...g.++++++..........................k"; // black
185 char xqName[] = "PH.R.AE..K.C................................" // white
186 "ph.r.ae..k.c................................"; // black
189 CollectPieceDescriptors ()
190 { // make a line of piece descriptions for use in the PGN Piece tag:
191 // dump all engine defined pieces, and pieces with non-standard names,
192 // but suppress black pieces that are the same as their white counterpart
194 static char buf[MSG_SIZ];
195 char *m, c, d, *pieceName = defaultName;
198 if(!pieceDefs) return "";
199 if(gameInfo.variant == VariantChu) return ""; // for now don't do this for Chu Shogi
200 if(gameInfo.variant == VariantShogi) pieceName = shogiName;
201 if(gameInfo.variant == VariantXiangqi) pieceName = xqName;
202 for(p=WhitePawn; p<EmptySquare; p++) {
203 if((c = pieceToChar[p]) == '.' || c == '~') continue; // does not participate
204 m = pieceDesc[p]; d = (c == '+' ? pieceToChar[DEMOTED p] : c);
205 if(p >= BlackPawn && pieceToChar[BLACK_TO_WHITE p] == toupper(c)
206 && (c != '+' || pieceToChar[DEMOTED BLACK_TO_WHITE p] == d)) { // black member of normal pair
207 char *wm = pieceDesc[BLACK_TO_WHITE p];
208 if(!m && !wm || m && wm && !strcmp(wm, m)) continue; // moves as a white piece
209 } else // white or unpaired black
210 if((p < BlackPawn || CharToPiece(toupper(d)) != EmptySquare) && // white or lone black
211 !pieceDesc[p] /*&& pieceName[p] == c*/) continue; // orthodox piece known by its usual name
212 // TODO: listing pieces because of unusual name can only be done if we have accurate Betza of all defaults
213 if(!m) m = defaultDesc[p];
215 snprintf(buf+len, MSG_SIZ-len, "%s%s%c:%s", len ? ";" : "", c == '+' ? "+" : "", d, m);
220 // [HGM] gen: configurable move generation from Betza notation sent by engine.
224 // alphabet "abcdefghijklmnopqrstuvwxyz"
225 char symmetry[] = "FBNW.FFW.NKN.NW.QR....W..N";
226 char xStep[] = "2110.130.102.10.00....0..2";
227 char yStep[] = "2132.133.313.20.11....1..3";
228 char dirType[] = "01000104000200000260050000";
229 // alphabet "a b c d e f g h i j k l m n o p q r s t u v w x y z "
230 int dirs1[] = { 0,0x3C,0,0,0,0xC3,0,0, 0,0,0,0xF0,0,0,0,0,0,0x0F,0 ,0,0,0 ,0,0,0,0 };
231 int dirs2[] = { 0,0x18,0,0,0,0x81,0,0xFF,0,0,0,0x60,0,0,0,0,0,0x06,0x66,0,0,0x99,0,0,0,0 };
233 int rot[][4] = { // rotation matrices for each direction
245 MovesFromString (Board board, int flags, int f, int r, char *desc, MoveCallback cb, VOIDSTAR cl)
248 int mine, his, dir, bit, occup, i;
249 if(flags & F_WHITE_ON_MOVE) his = 2, mine = 1; else his = 1, mine = 2;
250 while(*p) { // more moves to go
251 int expo = 1, dx, dy, x, y, mode, dirSet, retry=0, initial=0, jump=1, skip = 0;
252 if(*p == 'i') initial = 1, desc = ++p;
253 while(islower(*p)) p++; // skip prefixes
254 if(!isupper(*p)) return; // syntax error: no atom
255 dirSet = 0; // build direction set based on atom symmetry
256 switch(symmetry[*p-'A']) {
257 case 'B': expo = 0; // bishop, slide
258 case 'F': // diagonal atom (degenerate 4-fold)
259 while(islower(*desc) && (i = dirType[*desc-'a']) != '0') {
260 int b = dirs1[*desc-'a']; // use wide version
261 if( islower(desc[1]) &&
262 ((i | dirType[desc[1]-'a']) & 3) == 3) { // combinable (perpendicular dim)
263 b = dirs1[*desc-'a'] & dirs1[desc[1]-'a']; // intersect wide & perp wide
268 dirSet &= 0x55; if(!dirSet) dirSet = 0x55;
270 case 'R': expo = 0; // rook, slide
271 case 'W': // orthogonal atom (non-deg 4-fold)
272 while(islower(*desc) && (dirType[*desc-'a'] & ~4) != '0') dirSet |= dirs2[*desc++-'a'];
273 dirSet &= 0x55; if(!dirSet) dirSet = 0x55;
275 case 'N': // oblique atom (degenerate 8-fold)
276 while(islower(*desc) && (i = dirType[*desc-'a']) != '0') {
277 int b = dirs2[*desc-'a']; // when alone, use narrow version
278 if(desc[1] == 'h') b = dirs1[*desc-'a'], desc += 2; // dirs1 is wide version
279 else if(*desc == desc[1] || islower(desc[1]) && i < '4'
280 && ((i | dirType[desc[1]-'a']) & 3) == 3) { // combinable (perpendicular dim or same)
281 b = dirs1[*desc-'a'] & dirs2[desc[1]-'a']; // intersect wide & perp narrow
286 if(!dirSet) dirSet = 0xFF;
288 case 'Q': expo = 0; // queen, slide
289 case 'K': // non-deg (pseudo) 8-fold
290 dirSet=0x55; // start with orthogonal moves
291 retry = 1; // and schedule the diagonal moves for later
292 break; // should not have direction indicators
293 default: return; // syntax error: invalid atom
295 if(mine == 2) dirSet = dirSet >> 4 | dirSet << 4 & 255; // invert black moves
296 mode = 0; // build mode mask
297 if(*desc == 'm') mode |= 4, desc++;
298 if(*desc == 'c') mode |= his, desc++;
299 if(*desc == 'd') mode |= mine, desc++;
300 if(*desc == 'e') mode |= 8, desc++;
301 if(!mode) mode = his + 4;// no mode spec, use default = mc
302 if(*desc == 'p') mode |= 32, desc++;
303 if(*desc == 'g') mode |= 64, desc++;
304 if(*desc == 'o') mode |= 128, desc++;
305 if(*desc == 'n') jump = 0, desc++;
306 while(*desc == 'j') jump++, desc++;
307 dx = xStep[*p-'A'] - '0'; // step vector of atom
308 dy = yStep[*p-'A'] - '0';
309 if(isdigit(*++p)) expo = atoi(p++); // read exponent
310 if(expo > 9) p++; // allow double-digit
311 desc = p; // this is start of next move
312 if(initial && (board[r][f] != initialPosition[r][f] ||
313 r == 0 && board[TOUCHED_W] & 1<<f ||
314 r == BOARD_HEIGHT-1 && board[TOUCHED_B] & 1<<f ) ) continue;
315 if(expo > 1 && dx == 0 && dy == 0) { // castling indicated by O + number
318 if(dy == 1) skip = jump - 1, jump = 1; // on W & F atoms 'j' = skip first square
320 for(dir=0, bit=1; dir<8; dir++, bit += bit) { // loop over directions
321 int i = expo, j = skip, hop = mode, vx, vy;
322 if(!(bit & dirSet)) continue; // does not move in this direction
323 if(dy != 1) j = 0; //
324 vx = dx*rot[dir][0] + dy*rot[dir][1]; // rotate step vector
325 vy = dx*rot[dir][2] + dy*rot[dir][3];
326 x = f; y = r; // start square
328 x += vx; y += vy; // step to next square
329 if(y < 0 || y >= BOARD_HEIGHT) break; // vertically off-board: always done
330 if(x < BOARD_LEFT) { if(mode & 128) x += BOARD_RGHT - BOARD_LEFT; else break; }
331 if(x >= BOARD_RGHT) { if(mode & 128) x -= BOARD_RGHT - BOARD_LEFT; else break; }
332 if(j) { j--; continue; } // skip irrespective of occupation
333 if(!jump && board[y - vy + vy/2][x - vx + vx/2] != EmptySquare) break; // blocked
334 if(jump > 1 && board[y - vy + vy/2][x - vx + vx/2] == EmptySquare) break; // no hop
335 if(board[y][x] < BlackPawn) occup = 1; else
336 if(board[y][x] < EmptySquare) occup = 2; else
338 if(hop & 32+64) { if(occup != 4) { if(hop & 64 && i != 1) i = 2; hop &= 31; } continue; } // hopper
339 if(mode & 8 && y == board[EP_RANK] && occup == 4 && board[EP_FILE] == x) { // to e.p. square
340 cb(board, flags, mine == 1 ? WhiteCapturesEnPassant : BlackCapturesEnPassant, r, f, y, x, cl);
342 if(mode & 16) { // castling
343 i = 2; // kludge to elongate move indefinitely
344 if(occup == 4) continue; // skip empty squares
345 if(x == BOARD_LEFT && board[y][x] == initialPosition[y][x]) // reached initial corner piece
346 cb(board, flags, mine == 1 ? WhiteQueenSideCastle : BlackQueenSideCastle, r, f, y, f - expo, cl);
347 if(x == BOARD_RGHT-1 && board[y][x] == initialPosition[y][x])
348 cb(board, flags, mine == 1 ? WhiteKingSideCastle : BlackKingSideCastle, r, f, y, f + expo, cl);
351 if(occup & mode) cb(board, flags, NormalMove, r, f, y, x, cl); // allowed, generate
352 if(occup != 4) break; // not valid transit square
355 dx = dy = 1; dirSet = 0x99; // prepare for diagonal moves of K,Q
356 } while(retry--); // and start doing them
360 // [HGM] move generation now based on hierarchy of subroutines for rays and combinations of rays
363 SlideForward (Board board, int flags, int rf, int ff, MoveCallback callback, VOIDSTAR closure)
368 if (rt >= BOARD_HEIGHT) break;
369 if (SameColor(board[rf][ff], board[rt][ft])) break;
370 callback(board, flags, NormalMove, rf, ff, rt, ft, closure);
371 if (board[rt][ft] != EmptySquare) break;
376 SlideBackward (Board board, int flags, int rf, int ff, MoveCallback callback, VOIDSTAR closure)
382 if (SameColor(board[rf][ff], board[rt][ft])) break;
383 callback(board, flags, NormalMove, rf, ff, rt, ft, closure);
384 if (board[rt][ft] != EmptySquare) break;
389 SlideVertical (Board board, int flags, int rf, int ff, MoveCallback callback, VOIDSTAR closure)
391 SlideForward(board, flags, rf, ff, callback, closure);
392 SlideBackward(board, flags, rf, ff, callback, closure);
396 SlideSideways (Board board, int flags, int rf, int ff, MoveCallback callback, VOIDSTAR closure)
398 int i, s, rt = rf, ft;
399 for(s = -1; s <= 1; s+= 2) {
402 if (ft < BOARD_LEFT || ft >= BOARD_RGHT) break;
403 if (SameColor(board[rf][ff], board[rt][ft])) break;
404 callback(board, flags, NormalMove, rf, ff, rt, ft, closure);
405 if (board[rt][ft] != EmptySquare) break;
411 SlideDiagForward (Board board, int flags, int rf, int ff, MoveCallback callback, VOIDSTAR closure)
414 for(s = -1; s <= 1; s+= 2) {
418 if (rt >= BOARD_HEIGHT || ft < BOARD_LEFT || ft >= BOARD_RGHT) break;
419 if (SameColor(board[rf][ff], board[rt][ft])) break;
420 callback(board, flags, NormalMove, rf, ff, rt, ft, closure);
421 if (board[rt][ft] != EmptySquare) break;
427 SlideDiagBackward (Board board, int flags, int rf, int ff, MoveCallback callback, VOIDSTAR closure)
430 for(s = -1; s <= 1; s+= 2) {
434 if (rt < 0 || ft < BOARD_LEFT || ft >= BOARD_RGHT) break;
435 if (SameColor(board[rf][ff], board[rt][ft])) break;
436 callback(board, flags, NormalMove, rf, ff, rt, ft, closure);
437 if (board[rt][ft] != EmptySquare) break;
443 Rook (Board board, int flags, int rf, int ff, MoveCallback callback, VOIDSTAR closure)
445 SlideVertical(board, flags, rf, ff, callback, closure);
446 SlideSideways(board, flags, rf, ff, callback, closure);
450 Bishop (Board board, int flags, int rf, int ff, MoveCallback callback, VOIDSTAR closure)
452 SlideDiagForward(board, flags, rf, ff, callback, closure);
453 SlideDiagBackward(board, flags, rf, ff, callback, closure);
457 Sting (Board board, int flags, int rf, int ff, int dy, int dx, MoveCallback callback, VOIDSTAR closure)
458 { // Lion-like move of Horned Falcon and Souring Eagle
459 int ft = ff + dx, rt = rf + dy;
460 if (rt < 0 || rt >= BOARD_HEIGHT || ft < BOARD_LEFT || ft >= BOARD_RGHT) return;
461 if (!SameColor(board[rf][ff], board[rt][ft]))
462 callback(board, flags, board[rt][ft] != EmptySquare ? FirstLeg : NormalMove, rf, ff, rt, ft, closure);
464 if (rt < 0 || rt >= BOARD_HEIGHT || ft < BOARD_LEFT || ft >= BOARD_RGHT) return;
465 if (!SameColor(board[rf][ff], board[rt][ft]))
466 callback(board, flags, NormalMove, rf, ff, rt, ft, closure);
470 StepForward (Board board, int flags, int rf, int ff, MoveCallback callback, VOIDSTAR closure)
472 int ft = ff, rt = rf + 1;
473 if (rt >= BOARD_HEIGHT) return;
474 if (SameColor(board[rf][ff], board[rt][ft])) return;
475 callback(board, flags, NormalMove, rf, ff, rt, ft, closure);
479 StepBackward (Board board, int flags, int rf, int ff, MoveCallback callback, VOIDSTAR closure)
481 int ft = ff, rt = rf - 1;
483 if (SameColor(board[rf][ff], board[rt][ft])) return;
484 callback(board, flags, NormalMove, rf, ff, rt, ft, closure);
488 StepSideways (Board board, int flags, int rf, int ff, MoveCallback callback, VOIDSTAR closure)
492 if (!(rt >= BOARD_HEIGHT || ft >= BOARD_RGHT) && !SameColor(board[rf][ff], board[rt][ft]))
493 callback(board, flags, NormalMove, rf, ff, rt, ft, closure);
495 if (!(rt >= BOARD_HEIGHT || ft < BOARD_LEFT) && !SameColor(board[rf][ff], board[rt][ft]))
496 callback(board, flags, NormalMove, rf, ff, rt, ft, closure);
500 StepDiagForward (Board board, int flags, int rf, int ff, MoveCallback callback, VOIDSTAR closure)
503 if (rt >= BOARD_HEIGHT) return;
505 if (!(rt >= BOARD_HEIGHT || ft >= BOARD_RGHT) && !SameColor(board[rf][ff], board[rt][ft]))
506 callback(board, flags, NormalMove, rf, ff, rt, ft, closure);
508 if (!(rt >= BOARD_HEIGHT || ft < BOARD_LEFT) && !SameColor(board[rf][ff], board[rt][ft]))
509 callback(board, flags, NormalMove, rf, ff, rt, ft, closure);
513 StepDiagBackward (Board board, int flags, int rf, int ff, MoveCallback callback, VOIDSTAR closure)
518 if (!(rt < 0 || ft >= BOARD_RGHT) && !SameColor(board[rf][ff], board[rt][ft]))
519 callback(board, flags, NormalMove, rf, ff, rt, ft, closure);
521 if (!(rt < 0 || ft < BOARD_LEFT) && !SameColor(board[rf][ff], board[rt][ft]))
522 callback(board, flags, NormalMove, rf, ff, rt, ft, closure);
526 StepVertical (Board board, int flags, int rf, int ff, MoveCallback callback, VOIDSTAR closure)
528 StepForward(board, flags, rf, ff, callback, closure);
529 StepBackward(board, flags, rf, ff, callback, closure);
533 Ferz (Board board, int flags, int rf, int ff, MoveCallback callback, VOIDSTAR closure)
535 StepDiagForward(board, flags, rf, ff, callback, closure);
536 StepDiagBackward(board, flags, rf, ff, callback, closure);
540 Wazir (Board board, int flags, int rf, int ff, MoveCallback callback, VOIDSTAR closure)
542 StepVertical(board, flags, rf, ff, callback, closure);
543 StepSideways(board, flags, rf, ff, callback, closure);
547 Knight (Board board, int flags, int rf, int ff, MoveCallback callback, VOIDSTAR closure)
550 for (i = -1; i <= 1; i += 2)
551 for (j = -1; j <= 1; j += 2)
552 for (s = 1; s <= 2; s++) {
555 if (!(rt < 0 || rt >= BOARD_HEIGHT || ft < BOARD_LEFT || ft >= BOARD_RGHT)
556 && ( gameInfo.variant != VariantXiangqi || board[rf+i*(s-1)][ff+j*(2-s)] == EmptySquare)
557 && !SameColor(board[rf][ff], board[rt][ft]))
558 callback(board, flags, NormalMove, rf, ff, rt, ft, closure);
562 /* Call callback once for each pseudo-legal move in the given
563 position, except castling moves. A move is pseudo-legal if it is
564 legal, or if it would be legal except that it leaves the king in
565 check. In the arguments, epfile is EP_NONE if the previous move
566 was not a double pawn push, or the file 0..7 if it was, or
567 EP_UNKNOWN if we don't know and want to allow all e.p. captures.
568 Promotion moves generated are to Queen only.
571 GenPseudoLegal (Board board, int flags, MoveCallback callback, VOIDSTAR closure, ChessSquare filter)
572 // speed: only do moves with this piece type
575 int i, j, d, s, fs, rs, rt, ft, m;
576 int epfile = (signed char)board[EP_STATUS]; // [HGM] gamestate: extract ep status from board
577 int promoRank = gameInfo.variant == VariantMakruk || gameInfo.variant == VariantGrand || gameInfo.variant == VariantChuChess ? 3 : 1;
579 for (rf = 0; rf < BOARD_HEIGHT; rf++)
580 for (ff = BOARD_LEFT; ff < BOARD_RGHT; ff++) {
583 if(board[rf][ff] == EmptySquare) continue;
584 if ((flags & F_WHITE_ON_MOVE) != (board[rf][ff] < BlackPawn)) continue; // [HGM] speed: wrong color
585 m = 0; piece = board[rf][ff];
586 if(PieceToChar(piece) == '~')
587 piece = (ChessSquare) ( DEMOTED piece );
588 if(filter != EmptySquare && piece != filter) continue;
589 if(pieceDefs && pieceDesc[piece]) { // [HGM] gen: use engine-defined moves
590 MovesFromString(board, flags, ff, rf, pieceDesc[piece], callback, closure);
593 if(IS_SHOGI(gameInfo.variant))
594 piece = (ChessSquare) ( SHOGI piece );
596 switch ((int)piece) {
597 /* case EmptySquare: [HGM] this is nonsense, and conflicts with Shogi cases */
599 /* can't happen ([HGM] except for faries...) */
603 if(gameInfo.variant == VariantXiangqi) {
604 /* [HGM] capture and move straight ahead in Xiangqi */
605 if (rf < BOARD_HEIGHT-1 &&
606 !SameColor(board[rf][ff], board[rf + 1][ff]) ) {
607 callback(board, flags, NormalMove,
608 rf, ff, rf + 1, ff, closure);
610 /* and move sideways when across the river */
611 for (s = -1; s <= 1; s += 2) {
612 if (rf >= BOARD_HEIGHT>>1 &&
613 ff + s >= BOARD_LEFT && ff + s < BOARD_RGHT &&
614 !WhitePiece(board[rf][ff+s]) ) {
615 callback(board, flags, NormalMove,
616 rf, ff, rf, ff+s, closure);
621 if (rf < BOARD_HEIGHT-1 && board[rf + 1][ff] == EmptySquare) {
622 callback(board, flags,
623 rf >= BOARD_HEIGHT-1-promoRank ? WhitePromotion : NormalMove,
624 rf, ff, rf + 1, ff, closure);
626 if (rf <= (BOARD_HEIGHT>>1)-3 && board[rf+1][ff] == EmptySquare && // [HGM] grand: also on 3rd rank on 10-board
627 gameInfo.variant != VariantShatranj && /* [HGM] */
628 gameInfo.variant != VariantCourier && /* [HGM] */
629 board[rf+2][ff] == EmptySquare ) {
630 callback(board, flags, NormalMove,
631 rf, ff, rf+2, ff, closure);
633 for (s = -1; s <= 1; s += 2) {
634 if (rf < BOARD_HEIGHT-1 && ff + s >= BOARD_LEFT && ff + s < BOARD_RGHT &&
635 ((flags & F_KRIEGSPIEL_CAPTURE) ||
636 BlackPiece(board[rf + 1][ff + s]))) {
637 callback(board, flags,
638 rf >= BOARD_HEIGHT-1-promoRank ? WhitePromotion : NormalMove,
639 rf, ff, rf + 1, ff + s, closure);
641 if (rf >= BOARD_HEIGHT+1>>1) {// [HGM] grand: 4th & 5th rank on 10-board
642 if (ff + s >= BOARD_LEFT && ff + s < BOARD_RGHT &&
643 (epfile == ff + s || epfile == EP_UNKNOWN) && rf < BOARD_HEIGHT-3 &&
644 board[rf][ff + s] == BlackPawn &&
645 board[rf+1][ff + s] == EmptySquare) {
646 callback(board, flags, WhiteCapturesEnPassant,
647 rf, ff, rf+1, ff + s, closure);
654 if(gameInfo.variant == VariantXiangqi) {
655 /* [HGM] capture straight ahead in Xiangqi */
656 if (rf > 0 && !SameColor(board[rf][ff], board[rf - 1][ff]) ) {
657 callback(board, flags, NormalMove,
658 rf, ff, rf - 1, ff, closure);
660 /* and move sideways when across the river */
661 for (s = -1; s <= 1; s += 2) {
662 if (rf < BOARD_HEIGHT>>1 &&
663 ff + s >= BOARD_LEFT && ff + s < BOARD_RGHT &&
664 !BlackPiece(board[rf][ff+s]) ) {
665 callback(board, flags, NormalMove,
666 rf, ff, rf, ff+s, closure);
671 if (rf > 0 && board[rf - 1][ff] == EmptySquare) {
672 callback(board, flags,
673 rf <= promoRank ? BlackPromotion : NormalMove,
674 rf, ff, rf - 1, ff, closure);
676 if (rf >= (BOARD_HEIGHT+1>>1)+2 && board[rf-1][ff] == EmptySquare && // [HGM] grand
677 gameInfo.variant != VariantShatranj && /* [HGM] */
678 gameInfo.variant != VariantCourier && /* [HGM] */
679 board[rf-2][ff] == EmptySquare) {
680 callback(board, flags, NormalMove,
681 rf, ff, rf-2, ff, closure);
683 for (s = -1; s <= 1; s += 2) {
684 if (rf > 0 && ff + s >= BOARD_LEFT && ff + s < BOARD_RGHT &&
685 ((flags & F_KRIEGSPIEL_CAPTURE) ||
686 WhitePiece(board[rf - 1][ff + s]))) {
687 callback(board, flags,
688 rf <= promoRank ? BlackPromotion : NormalMove,
689 rf, ff, rf - 1, ff + s, closure);
691 if (rf < BOARD_HEIGHT>>1) {
692 if (ff + s >= BOARD_LEFT && ff + s < BOARD_RGHT &&
693 (epfile == ff + s || epfile == EP_UNKNOWN) && rf > 2 &&
694 board[rf][ff + s] == WhitePawn &&
695 board[rf-1][ff + s] == EmptySquare) {
696 callback(board, flags, BlackCapturesEnPassant,
697 rf, ff, rf-1, ff + s, closure);
707 for (i = -1; i <= 1; i += 2)
708 for (j = -1; j <= 1; j += 2)
709 for (s = 1; s <= 2; s++) {
712 if (!(rt < 0 || rt >= BOARD_HEIGHT || ft < BOARD_LEFT || ft >= BOARD_RGHT)
713 && ( gameInfo.variant != VariantXiangqi || board[rf+i*(s-1)][ff+j*(2-s)] == EmptySquare)
714 && !SameColor(board[rf][ff], board[rt][ft]))
715 callback(board, flags, NormalMove,
716 rf, ff, rt, ft, closure);
720 case SHOGI WhiteKnight:
721 for (s = -1; s <= 1; s += 2) {
722 if (rf < BOARD_HEIGHT-2 && ff + s >= BOARD_LEFT && ff + s < BOARD_RGHT &&
723 !SameColor(board[rf][ff], board[rf + 2][ff + s])) {
724 callback(board, flags, NormalMove,
725 rf, ff, rf + 2, ff + s, closure);
730 case SHOGI BlackKnight:
731 for (s = -1; s <= 1; s += 2) {
732 if (rf > 1 && ff + s >= BOARD_LEFT && ff + s < BOARD_RGHT &&
733 !SameColor(board[rf][ff], board[rf - 2][ff + s])) {
734 callback(board, flags, NormalMove,
735 rf, ff, rf - 2, ff + s, closure);
742 for (d = 0; d <= 1; d++)
743 for (s = -1; s <= 1; s += 2) {
746 rt = rf + (i * s) * d;
747 ft = ff + (i * s) * (1 - d);
748 if (rt < 0 || rt >= BOARD_HEIGHT || ft < BOARD_LEFT || ft >= BOARD_RGHT) break;
749 if (m == 0 && board[rt][ft] == EmptySquare)
750 callback(board, flags, NormalMove,
751 rf, ff, rt, ft, closure);
752 if (m == 1 && board[rt][ft] != EmptySquare &&
753 !SameColor(board[rf][ff], board[rt][ft]) )
754 callback(board, flags, NormalMove,
755 rf, ff, rt, ft, closure);
756 if (board[rt][ft] != EmptySquare && m++) break;
761 /* Gold General (and all its promoted versions) . First do the */
762 /* diagonal forward steps, then proceed as normal Wazir */
763 case SHOGI (PROMOTED WhitePawn):
764 if(gameInfo.variant == VariantShogi) goto WhiteGold;
765 case SHOGI (PROMOTED BlackPawn):
766 if(gameInfo.variant == VariantShogi) goto BlackGold;
767 SlideVertical(board, flags, rf, ff, callback, closure);
770 case SHOGI (PROMOTED WhiteKnight):
771 if(gameInfo.variant == VariantShogi) goto WhiteGold;
772 case SHOGI BlackDrunk:
773 case SHOGI BlackAlfil:
774 Ferz(board, flags, rf, ff, callback, closure);
775 StepSideways(board, flags, rf, ff, callback, closure);
776 StepBackward(board, flags, rf, ff, callback, closure);
779 case SHOGI (PROMOTED BlackKnight):
780 if(gameInfo.variant == VariantShogi) goto BlackGold;
781 case SHOGI WhiteDrunk:
782 case SHOGI WhiteAlfil:
783 Ferz(board, flags, rf, ff, callback, closure);
784 StepSideways(board, flags, rf, ff, callback, closure);
785 StepForward(board, flags, rf, ff, callback, closure);
789 case SHOGI WhiteStag:
790 case SHOGI BlackStag:
791 if(gameInfo.variant == VariantShogi) goto BlackGold;
792 SlideVertical(board, flags, rf, ff, callback, closure);
793 Ferz(board, flags, rf, ff, callback, closure);
794 StepSideways(board, flags, rf, ff, callback, closure);
797 case SHOGI (PROMOTED WhiteQueen):
798 case SHOGI WhiteTokin:
799 case SHOGI WhiteWazir:
801 StepDiagForward(board, flags, rf, ff, callback, closure);
802 Wazir(board, flags, rf, ff, callback, closure);
805 case SHOGI (PROMOTED BlackQueen):
806 case SHOGI BlackTokin:
807 case SHOGI BlackWazir:
809 StepDiagBackward(board, flags, rf, ff, callback, closure);
810 Wazir(board, flags, rf, ff, callback, closure);
815 Wazir(board, flags, rf, ff, callback, closure);
818 case SHOGI WhiteMarshall:
819 case SHOGI BlackMarshall:
820 Ferz(board, flags, rf, ff, callback, closure);
821 for (d = 0; d <= 1; d++)
822 for (s = -2; s <= 2; s += 4) {
824 ft = ff + s * (1 - d);
825 if (rt < 0 || rt >= BOARD_HEIGHT || ft < BOARD_LEFT || ft >= BOARD_RGHT) continue;
826 if (!SameColor(board[rf][ff], board[rt][ft]) )
827 callback(board, flags, NormalMove, rf, ff, rt, ft, closure);
831 case SHOGI WhiteAngel:
832 case SHOGI BlackAngel:
833 Wazir(board, flags, rf, ff, callback, closure);
837 /* [HGM] support Shatranj pieces */
838 for (rs = -1; rs <= 1; rs += 2)
839 for (fs = -1; fs <= 1; fs += 2) {
842 if (!(rt < 0 || rt >= BOARD_HEIGHT || ft < BOARD_LEFT || ft >= BOARD_RGHT)
843 && ( gameInfo.variant != VariantXiangqi ||
844 board[rf+rs][ff+fs] == EmptySquare && (2*rf < BOARD_HEIGHT) == (2*rt < BOARD_HEIGHT) )
846 && !SameColor(board[rf][ff], board[rt][ft]))
847 callback(board, flags, NormalMove,
848 rf, ff, rt, ft, closure);
849 if(gameInfo.variant == VariantShatranj || gameInfo.variant == VariantCourier ||
850 gameInfo.variant == VariantChu || gameInfo.variant == VariantXiangqi) continue; // classical Alfil
851 rt = rf + rs; // in unknown variant we assume Modern Elephant, which can also do one step
853 if (!(rt < 0 || rt >= BOARD_HEIGHT || ft < BOARD_LEFT || ft >= BOARD_RGHT)
854 && !SameColor(board[rf][ff], board[rt][ft]))
855 callback(board, flags, NormalMove,
856 rf, ff, rt, ft, closure);
858 if(gameInfo.variant == VariantSpartan)
859 for(fs = -1; fs <= 1; fs += 2) {
861 if (!(ft < BOARD_LEFT || ft >= BOARD_RGHT) && board[rf][ft] == EmptySquare)
862 callback(board, flags, NormalMove, rf, ff, rf, ft, closure);
866 /* Make Dragon-Horse also do Dababba moves outside Shogi, for better disambiguation in variant Fairy */
869 if(gameInfo.variant == VariantChuChess) goto DragonHorse;
870 for (d = 0; d <= 1; d++) // Dababba moves that Rook cannot do
871 for (s = -2; s <= 2; s += 4) {
873 ft = ff + s * (1 - d);
874 if (rt < 0 || rt >= BOARD_HEIGHT || ft < BOARD_LEFT || ft >= BOARD_RGHT) continue;
875 if (SameColor(board[rf][ff], board[rt][ft])) continue;
876 callback(board, flags, NormalMove, rf, ff, rt, ft, closure);
879 /* Shogi Dragon Horse has to continue with Wazir after Bishop */
880 case SHOGI WhiteCardinal:
881 case SHOGI BlackCardinal:
882 case SHOGI WhitePCardinal:
883 case SHOGI BlackPCardinal:
885 Bishop(board, flags, rf, ff, callback, closure);
886 Wazir(board, flags, rf, ff, callback, closure);
889 /* Capablanca Archbishop continues as Knight */
892 Knight(board, flags, rf, ff, callback, closure);
894 /* Shogi Bishops are ordinary Bishops */
895 case SHOGI WhiteBishop:
896 case SHOGI BlackBishop:
897 case SHOGI WhitePBishop:
898 case SHOGI BlackPBishop:
901 Bishop(board, flags, rf, ff, callback, closure);
904 /* Shogi Lance is unlike anything, and asymmetric at that */
905 case SHOGI WhiteQueen:
906 if(gameInfo.variant == VariantChu) goto doQueen;
910 if (rt >= BOARD_HEIGHT) break;
911 if (SameColor(board[rf][ff], board[rt][ft])) break;
912 callback(board, flags, NormalMove,
913 rf, ff, rt, ft, closure);
914 if (board[rt][ft] != EmptySquare) break;
918 case SHOGI BlackQueen:
919 if(gameInfo.variant == VariantChu) goto doQueen;
924 if (SameColor(board[rf][ff], board[rt][ft])) break;
925 callback(board, flags, NormalMove,
926 rf, ff, rt, ft, closure);
927 if (board[rt][ft] != EmptySquare) break;
931 /* Make Dragon-King Dababba & Rook-like outside Shogi, for better disambiguation in variant Fairy */
934 if(gameInfo.variant == VariantChuChess) goto DragonKing;
935 for (d = 0; d <= 1; d++) // Dababba moves that Rook cannot do
936 for (s = -2; s <= 2; s += 4) {
938 ft = ff + s * (1 - d);
939 if (rt < 0 || rt >= BOARD_HEIGHT || ft < BOARD_LEFT || ft >= BOARD_RGHT) continue;
940 if (board[rf+rt>>1][ff+ft>>1] == EmptySquare && gameInfo.variant != VariantSpartan) continue;
941 if (SameColor(board[rf][ff], board[rt][ft])) continue;
942 callback(board, flags, NormalMove, rf, ff, rt, ft, closure);
944 if(gameInfo.variant == VariantSpartan) // in Spartan Chess restrict range to modern Dababba
945 Wazir(board, flags, rf, ff, callback, closure);
947 Rook(board, flags, rf, ff, callback, closure);
950 /* Shogi Dragon King has to continue as Ferz after Rook moves */
951 case SHOGI WhiteDragon:
952 case SHOGI BlackDragon:
953 case SHOGI WhitePDragon:
954 case SHOGI BlackPDragon:
956 Rook(board, flags, rf, ff, callback, closure);
957 Ferz(board, flags, rf, ff, callback, closure);
961 /* Capablanca Chancellor sets flag to continue as Knight */
964 Rook(board, flags, rf, ff, callback, closure);
965 if(gameInfo.variant == VariantSpartan) // in Spartan Chess Chancellor is used for Dragon King.
966 Ferz(board, flags, rf, ff, callback, closure);
968 Knight(board, flags, rf, ff, callback, closure);
971 /* Shogi Rooks are ordinary Rooks */
972 case SHOGI WhiteRook:
973 case SHOGI BlackRook:
974 case SHOGI WhitePRook:
975 case SHOGI BlackPRook:
978 Rook(board, flags, rf, ff, callback, closure);
983 case SHOGI WhiteMother:
984 case SHOGI BlackMother:
986 Rook(board, flags, rf, ff, callback, closure);
987 Bishop(board, flags, rf, ff, callback, closure);
990 case SHOGI WhitePawn:
991 StepForward(board, flags, rf, ff, callback, closure);
994 case SHOGI BlackPawn:
995 StepBackward(board, flags, rf, ff, callback, closure);
999 if(gameInfo.variant != VariantMakruk && gameInfo.variant != VariantASEAN) goto commoner;
1000 case SHOGI WhiteFerz:
1001 Ferz(board, flags, rf, ff, callback, closure);
1002 StepForward(board, flags, rf, ff, callback, closure);
1006 if(gameInfo.variant != VariantMakruk && gameInfo.variant != VariantASEAN) goto commoner;
1007 case SHOGI BlackFerz:
1008 StepBackward(board, flags, rf, ff, callback, closure);
1012 /* [HGM] support Shatranj pieces */
1013 Ferz(board, flags, rf, ff, callback, closure);
1018 Knight(board, flags, rf, ff, callback, closure); // [HGM] superchess: use for Centaur
1021 case SHOGI WhiteMonarch:
1022 case SHOGI BlackMonarch:
1023 case SHOGI WhiteKing:
1024 case SHOGI BlackKing:
1027 Ferz(board, flags, rf, ff, callback, closure);
1028 Wazir(board, flags, rf, ff, callback, closure);
1031 case WhiteNightrider:
1032 case BlackNightrider:
1033 for (i = -1; i <= 1; i += 2)
1034 for (j = -1; j <= 1; j += 2)
1035 for (s = 1; s <= 2; s++) { int k;
1038 ft = ff + k*j*(3-s);
1039 if (rt < 0 || rt >= BOARD_HEIGHT || ft < BOARD_LEFT || ft >= BOARD_RGHT) break;
1040 if (SameColor(board[rf][ff], board[rt][ft])) break;
1041 callback(board, flags, NormalMove,
1042 rf, ff, rt, ft, closure);
1043 if (board[rt][ft] != EmptySquare) break;
1049 Bishop(board, flags, rf, ff, callback, closure);
1050 Rook(board, flags, rf, ff, callback, closure);
1051 Knight(board, flags, rf, ff, callback, closure);
1054 // Use Lance as Berolina / Spartan Pawn.
1056 if(gameInfo.variant == VariantSuper) goto Amazon;
1057 if (rf < BOARD_HEIGHT-1 && BlackPiece(board[rf + 1][ff]))
1058 callback(board, flags,
1059 rf >= BOARD_HEIGHT-1-promoRank ? WhitePromotion : NormalMove,
1060 rf, ff, rf + 1, ff, closure);
1061 for (s = -1; s <= 1; s += 2) {
1062 if (rf < BOARD_HEIGHT-1 && ff + s >= BOARD_LEFT && ff + s < BOARD_RGHT && board[rf + 1][ff + s] == EmptySquare)
1063 callback(board, flags,
1064 rf >= BOARD_HEIGHT-1-promoRank ? WhitePromotion : NormalMove,
1065 rf, ff, rf + 1, ff + s, closure);
1066 if (rf == 1 && ff + 2*s >= BOARD_LEFT && ff + 2*s < BOARD_RGHT && board[3][ff + 2*s] == EmptySquare )
1067 callback(board, flags, NormalMove, rf, ff, 3, ff + 2*s, closure);
1072 if(gameInfo.variant == VariantSuper) goto Amazon;
1073 if (rf > 0 && WhitePiece(board[rf - 1][ff]))
1074 callback(board, flags,
1075 rf <= promoRank ? BlackPromotion : NormalMove,
1076 rf, ff, rf - 1, ff, closure);
1077 for (s = -1; s <= 1; s += 2) {
1078 if (rf > 0 && ff + s >= BOARD_LEFT && ff + s < BOARD_RGHT && board[rf - 1][ff + s] == EmptySquare)
1079 callback(board, flags,
1080 rf <= promoRank ? BlackPromotion : NormalMove,
1081 rf, ff, rf - 1, ff + s, closure);
1082 if (rf == BOARD_HEIGHT-2 && ff + 2*s >= BOARD_LEFT && ff + 2*s < BOARD_RGHT && board[rf-2][ff + 2*s] == EmptySquare )
1083 callback(board, flags, NormalMove, rf, ff, rf-2, ff + 2*s, closure);
1087 case SHOGI WhiteNothing:
1088 case SHOGI BlackNothing:
1089 case SHOGI WhiteLion:
1090 case SHOGI BlackLion:
1093 for(rt = rf - 2; rt <= rf + 2; rt++) for(ft = ff - 2; ft <= ff + 2; ft++) {
1094 if (rt < 0 || rt >= BOARD_HEIGHT || ft < BOARD_LEFT || ft >= BOARD_RGHT) continue;
1095 if (!(ff == ft && rf == rt) && SameColor(board[rf][ff], board[rt][ft])) continue;
1096 callback(board, flags, (rt-rf)*(rt-rf) + (ff-ft)*(ff-ft) < 3 && board[rt][ft] != EmptySquare ? FirstLeg : NormalMove,
1097 rf, ff, rt, ft, closure);
1101 case SHOGI WhiteFalcon:
1102 case SHOGI BlackFalcon:
1103 case SHOGI WhitePDagger:
1104 case SHOGI BlackPDagger:
1105 SlideSideways(board, flags, rf, ff, callback, closure);
1106 StepVertical(board, flags, rf, ff, callback, closure);
1109 case SHOGI WhiteCobra:
1110 case SHOGI BlackCobra:
1111 StepVertical(board, flags, rf, ff, callback, closure);
1114 case SHOGI (PROMOTED WhiteFerz):
1115 if(gameInfo.variant == VariantShogi) goto WhiteGold;
1116 case SHOGI (PROMOTED BlackFerz):
1117 if(gameInfo.variant == VariantShogi) goto BlackGold;
1118 case SHOGI WhitePSword:
1119 case SHOGI BlackPSword:
1120 SlideVertical(board, flags, rf, ff, callback, closure);
1121 StepSideways(board, flags, rf, ff, callback, closure);
1124 case SHOGI WhiteUnicorn:
1125 case SHOGI BlackUnicorn:
1126 Ferz(board, flags, rf, ff, callback, closure);
1127 StepVertical(board, flags, rf, ff, callback, closure);
1130 case SHOGI WhiteMan:
1131 StepDiagForward(board, flags, rf, ff, callback, closure);
1132 StepVertical(board, flags, rf, ff, callback, closure);
1135 case SHOGI BlackMan:
1136 StepDiagBackward(board, flags, rf, ff, callback, closure);
1137 StepVertical(board, flags, rf, ff, callback, closure);
1140 case SHOGI WhiteHCrown:
1141 case SHOGI BlackHCrown:
1142 Bishop(board, flags, rf, ff, callback, closure);
1143 SlideSideways(board, flags, rf, ff, callback, closure);
1146 case SHOGI WhiteCrown:
1147 case SHOGI BlackCrown:
1148 Bishop(board, flags, rf, ff, callback, closure);
1149 SlideVertical(board, flags, rf, ff, callback, closure);
1152 case SHOGI WhiteHorned:
1153 Sting(board, flags, rf, ff, 1, 0, callback, closure);
1154 callback(board, flags, NormalMove, rf, ff, rf, ff, closure);
1155 if(killX >= 0) break;
1156 Bishop(board, flags, rf, ff, callback, closure);
1157 SlideSideways(board, flags, rf, ff, callback, closure);
1158 SlideBackward(board, flags, rf, ff, callback, closure);
1161 case SHOGI BlackHorned:
1162 Sting(board, flags, rf, ff, -1, 0, callback, closure);
1163 callback(board, flags, NormalMove, rf, ff, rf, ff, closure);
1164 if(killX >= 0) break;
1165 Bishop(board, flags, rf, ff, callback, closure);
1166 SlideSideways(board, flags, rf, ff, callback, closure);
1167 SlideForward(board, flags, rf, ff, callback, closure);
1170 case SHOGI WhiteEagle:
1171 Sting(board, flags, rf, ff, 1, 1, callback, closure);
1172 Sting(board, flags, rf, ff, 1, -1, callback, closure);
1173 callback(board, flags, NormalMove, rf, ff, rf, ff, closure);
1174 if(killX >= 0) break;
1175 Rook(board, flags, rf, ff, callback, closure);
1176 SlideDiagBackward(board, flags, rf, ff, callback, closure);
1179 case SHOGI BlackEagle:
1180 Sting(board, flags, rf, ff, -1, 1, callback, closure);
1181 Sting(board, flags, rf, ff, -1, -1, callback, closure);
1182 callback(board, flags, NormalMove, rf, ff, rf, ff, closure);
1183 if(killX >= 0) break;
1184 Rook(board, flags, rf, ff, callback, closure);
1185 SlideDiagForward(board, flags, rf, ff, callback, closure);
1188 case SHOGI WhiteDolphin:
1189 case SHOGI BlackHorse:
1190 SlideDiagBackward(board, flags, rf, ff, callback, closure);
1191 SlideVertical(board, flags, rf, ff, callback, closure);
1194 case SHOGI BlackDolphin:
1195 case SHOGI WhiteHorse:
1196 SlideDiagForward(board, flags, rf, ff, callback, closure);
1197 SlideVertical(board, flags, rf, ff, callback, closure);
1200 case SHOGI WhiteLance:
1201 SlideForward(board, flags, rf, ff, callback, closure);
1204 case SHOGI BlackLance:
1205 SlideBackward(board, flags, rf, ff, callback, closure);
1208 case WhiteFalcon: // [HGM] wild: for wildcards, self-capture symbolizes move to anywhere
1212 callback(board, flags, NormalMove, rf, ff, rf, ff, closure);
1225 int rFilter, fFilter; // [HGM] speed: sorry, but I get a bit tired of this closure madness
1226 Board xqCheckers, nullBoard;
1228 extern void GenLegalCallback P((Board board, int flags, ChessMove kind,
1229 int rf, int ff, int rt, int ft,
1233 GenLegalCallback (Board board, int flags, ChessMove kind, int rf, int ff, int rt, int ft, VOIDSTAR closure)
1235 register GenLegalClosure *cl = (GenLegalClosure *) closure;
1237 if(rFilter >= 0 && rFilter != rt || fFilter >= 0 && fFilter != ft) return; // [HGM] speed: ignore moves with wrong to-square
1239 if (board[EP_STATUS] == EP_IRON_LION && (board[rt][ft] == WhiteLion || board[rt][ft] == BlackLion)) return; //[HGM] lion
1241 if (!(flags & F_IGNORE_CHECK) ) {
1242 int check, promo = (gameInfo.variant == VariantSpartan && kind == BlackPromotion);
1245 for(r=0; r<BOARD_HEIGHT; r++) for(f=BOARD_LEFT; f<BOARD_RGHT; f++)
1246 kings += (board[r][f] == BlackKing);
1250 board[rf][ff] = BlackKing; // [HGM] spartan: promote to King before check-test
1252 check = CheckTest(board, flags, rf, ff, rt, ft,
1253 kind == WhiteCapturesEnPassant ||
1254 kind == BlackCapturesEnPassant);
1255 if(promo) board[rf][ff] = BlackLance;
1258 if (flags & F_ATOMIC_CAPTURE) {
1259 if (board[rt][ft] != EmptySquare ||
1260 kind == WhiteCapturesEnPassant || kind == BlackCapturesEnPassant) {
1262 ChessSquare king = (flags & F_WHITE_ON_MOVE) ? WhiteKing : BlackKing;
1263 if (board[rf][ff] == king) return;
1264 for (r = rt-1; r <= rt+1; r++) {
1265 for (f = ft-1; f <= ft+1; f++) {
1266 if (r >= 0 && r < BOARD_HEIGHT && f >= BOARD_LEFT && f < BOARD_RGHT &&
1267 board[r][f] == king) return;
1272 cl->cb(board, flags, kind, rf, ff, rt, ft, cl->cl);
1279 int captures; // [HGM] losers
1280 } LegalityTestClosure;
1283 /* Like GenPseudoLegal, but (1) include castling moves, (2) unless
1284 F_IGNORE_CHECK is set in the flags, omit moves that would leave the
1285 king in check, and (3) if F_ATOMIC_CAPTURE is set in the flags, omit
1286 moves that would destroy your own king. The CASTLE_OK flags are
1287 true if castling is not yet ruled out by a move of the king or
1288 rook. Return TRUE if the player on move is currently in check and
1289 F_IGNORE_CHECK is not set. [HGM] add castlingRights parameter */
1291 GenLegal (Board board, int flags, MoveCallback callback, VOIDSTAR closure, ChessSquare filter)
1294 int ff, ft, k, left, right, swap;
1295 int ignoreCheck = (flags & F_IGNORE_CHECK) != 0;
1296 ChessSquare wKing = WhiteKing, bKing = BlackKing, *castlingRights = board[CASTLING];
1297 int inCheck = !ignoreCheck && CheckTest(board, flags, -1, -1, -1, -1, FALSE); // kludge alert: this would mark pre-existing checkers if status==1
1302 xqCheckers[EP_STATUS] *= 2; // quasi: if previous CheckTest has been marking, we now set flag for suspending same checkers
1303 if(filter == EmptySquare) rFilter = fFilter = -1; // [HGM] speed: do not filter on square if we do not filter on piece
1304 GenPseudoLegal(board, flags, GenLegalCallback, (VOIDSTAR) &cl, filter);
1306 if (inCheck) return TRUE;
1308 /* Generate castling moves */
1309 if(gameInfo.variant == VariantKnightmate) { /* [HGM] Knightmate */
1310 wKing = WhiteUnicorn; bKing = BlackUnicorn;
1313 p = (flags & F_WHITE_ON_MOVE ? pieceDesc[wKing] : pieceDesc[bKing]);
1314 if(p && strchr(p, 'O')) return FALSE; // [HGM] gen: castlings were already generated from string
1316 for (ff = BOARD_WIDTH>>1; ff >= (BOARD_WIDTH-1)>>1; ff-- /*ics wild 1*/) {
1317 if ((flags & F_WHITE_ON_MOVE) &&
1318 (flags & F_WHITE_KCASTLE_OK) &&
1319 board[0][ff] == wKing &&
1320 board[0][ff + 1] == EmptySquare &&
1321 board[0][ff + 2] == EmptySquare &&
1322 board[0][BOARD_RGHT-3] == EmptySquare &&
1323 board[0][BOARD_RGHT-2] == EmptySquare &&
1324 board[0][BOARD_RGHT-1] == WhiteRook &&
1325 castlingRights[0] != NoRights && /* [HGM] check rights */
1326 ( castlingRights[2] == ff || castlingRights[6] == ff ) &&
1328 (!CheckTest(board, flags, 0, ff, 0, ff + 1, FALSE) &&
1329 !CheckTest(board, flags, 0, ff, 0, BOARD_RGHT-3, FALSE) &&
1330 (gameInfo.variant != VariantJanus || !CheckTest(board, flags, 0, ff, 0, BOARD_RGHT-2, FALSE)) &&
1331 !CheckTest(board, flags, 0, ff, 0, ff + 2, FALSE)))) {
1333 callback(board, flags,
1334 ff==BOARD_WIDTH>>1 ? WhiteKingSideCastle : WhiteKingSideCastleWild,
1335 0, ff, 0, ff + ((gameInfo.boardWidth+2)>>2) + (gameInfo.variant == VariantJanus), closure);
1337 if ((flags & F_WHITE_ON_MOVE) &&
1338 (flags & F_WHITE_QCASTLE_OK) &&
1339 board[0][ff] == wKing &&
1340 board[0][ff - 1] == EmptySquare &&
1341 board[0][ff - 2] == EmptySquare &&
1342 board[0][BOARD_LEFT+2] == EmptySquare &&
1343 board[0][BOARD_LEFT+1] == EmptySquare &&
1344 board[0][BOARD_LEFT+0] == WhiteRook &&
1345 castlingRights[1] != NoRights && /* [HGM] check rights */
1346 ( castlingRights[2] == ff || castlingRights[6] == ff ) &&
1348 (!CheckTest(board, flags, 0, ff, 0, ff - 1, FALSE) &&
1349 !CheckTest(board, flags, 0, ff, 0, BOARD_LEFT+3, FALSE) &&
1350 !CheckTest(board, flags, 0, ff, 0, ff - 2, FALSE)))) {
1352 callback(board, flags,
1353 ff==BOARD_WIDTH>>1 ? WhiteQueenSideCastle : WhiteQueenSideCastleWild,
1354 0, ff, 0, ff - ((gameInfo.boardWidth+2)>>2), closure);
1356 if (!(flags & F_WHITE_ON_MOVE) &&
1357 (flags & F_BLACK_KCASTLE_OK) &&
1358 board[BOARD_HEIGHT-1][ff] == bKing &&
1359 board[BOARD_HEIGHT-1][ff + 1] == EmptySquare &&
1360 board[BOARD_HEIGHT-1][ff + 2] == EmptySquare &&
1361 board[BOARD_HEIGHT-1][BOARD_RGHT-3] == EmptySquare &&
1362 board[BOARD_HEIGHT-1][BOARD_RGHT-2] == EmptySquare &&
1363 board[BOARD_HEIGHT-1][BOARD_RGHT-1] == BlackRook &&
1364 castlingRights[3] != NoRights && /* [HGM] check rights */
1365 ( castlingRights[5] == ff || castlingRights[7] == ff ) &&
1367 (!CheckTest(board, flags, BOARD_HEIGHT-1, ff, BOARD_HEIGHT-1, ff + 1, FALSE) &&
1368 !CheckTest(board, flags, BOARD_HEIGHT-1, ff, BOARD_HEIGHT-1, BOARD_RGHT-3, FALSE) &&
1369 (gameInfo.variant != VariantJanus || !CheckTest(board, flags, BOARD_HEIGHT-1, ff, BOARD_HEIGHT-1, BOARD_RGHT-2, FALSE)) &&
1370 !CheckTest(board, flags, BOARD_HEIGHT-1, ff, BOARD_HEIGHT-1, ff + 2, FALSE)))) {
1372 callback(board, flags,
1373 ff==BOARD_WIDTH>>1 ? BlackKingSideCastle : BlackKingSideCastleWild,
1374 BOARD_HEIGHT-1, ff, BOARD_HEIGHT-1, ff + ((gameInfo.boardWidth+2)>>2) + (gameInfo.variant == VariantJanus), closure);
1376 if (!(flags & F_WHITE_ON_MOVE) &&
1377 (flags & F_BLACK_QCASTLE_OK) &&
1378 board[BOARD_HEIGHT-1][ff] == bKing &&
1379 board[BOARD_HEIGHT-1][ff - 1] == EmptySquare &&
1380 board[BOARD_HEIGHT-1][ff - 2] == EmptySquare &&
1381 board[BOARD_HEIGHT-1][BOARD_LEFT+2] == EmptySquare &&
1382 board[BOARD_HEIGHT-1][BOARD_LEFT+1] == EmptySquare &&
1383 board[BOARD_HEIGHT-1][BOARD_LEFT+0] == BlackRook &&
1384 castlingRights[4] != NoRights && /* [HGM] check rights */
1385 ( castlingRights[5] == ff || castlingRights[7] == ff ) &&
1387 (!CheckTest(board, flags, BOARD_HEIGHT-1, ff, BOARD_HEIGHT-1, ff - 1, FALSE) &&
1388 !CheckTest(board, flags, BOARD_HEIGHT-1, ff, BOARD_HEIGHT-1, BOARD_LEFT+3, FALSE) &&
1389 !CheckTest(board, flags, BOARD_HEIGHT-1, ff, BOARD_HEIGHT-1, ff - 2, FALSE)))) {
1391 callback(board, flags,
1392 ff==BOARD_WIDTH>>1 ? BlackQueenSideCastle : BlackQueenSideCastleWild,
1393 BOARD_HEIGHT-1, ff, BOARD_HEIGHT-1, ff - ((gameInfo.boardWidth+2)>>2), closure);
1397 if((swap = gameInfo.variant == VariantSChess) || flags & F_FRC_TYPE_CASTLING) {
1399 /* generate all potential FRC castling moves (KxR), ignoring flags */
1400 /* [HGM] test if the Rooks we find have castling rights */
1401 /* In S-Chess we generate RxK for allowed castlings, for gating at Rook square */
1404 if ((flags & F_WHITE_ON_MOVE) != 0) {
1405 ff = castlingRights[2]; /* King file if we have any rights */
1406 if(ff != NoRights && board[0][ff] == WhiteKing) {
1407 if (appData.debugMode) {
1408 fprintf(debugFP, "FRC castling, %d %d %d %d %d %d\n",
1409 castlingRights[0],castlingRights[1],ff,castlingRights[3],castlingRights[4],castlingRights[5]);
1411 ft = castlingRights[0]; /* Rook file if we have H-side rights */
1413 right = BOARD_RGHT-2;
1414 if(ff == BOARD_RGHT-2) left = right = ff-1; /* special case */
1415 for(k=left; k<=right && ft != NoRights; k++) /* first test if blocked */
1416 if(k != ft && board[0][k] != EmptySquare) ft = NoRights;
1417 for(k=left; k<right && ft != NoRights; k++) /* then if not checked */
1418 if(!ignoreCheck && CheckTest(board, flags, 0, ff, 0, k, FALSE)) ft = NoRights;
1419 if(ft != NoRights && board[0][ft] == WhiteRook) {
1420 if(flags & F_FRC_TYPE_CASTLING) callback(board, flags, WhiteHSideCastleFR, 0, ff, 0, ft, closure);
1421 if(swap) callback(board, flags, WhiteHSideCastleFR, 0, ft, 0, ff, closure);
1424 ft = castlingRights[1]; /* Rook file if we have A-side rights */
1425 left = BOARD_LEFT+2;
1427 if(ff <= BOARD_LEFT+2) { left = ff+1; right = BOARD_LEFT+3; }
1428 for(k=left; k<=right && ft != NoRights; k++) /* first test if blocked */
1429 if(k != ft && board[0][k] != EmptySquare) ft = NoRights;
1430 if(ft == 0 && ff != 1 && board[0][1] != EmptySquare) ft = NoRights; /* Rook can be blocked on b1 */
1431 if(ff > BOARD_LEFT+2)
1432 for(k=left+1; k<=right && ft != NoRights; k++) /* then if not checked */
1433 if(!ignoreCheck && CheckTest(board, flags, 0, ff, 0, k, FALSE)) ft = NoRights;
1434 if(ft != NoRights && board[0][ft] == WhiteRook) {
1435 if(flags & F_FRC_TYPE_CASTLING) callback(board, flags, WhiteASideCastleFR, 0, ff, 0, ft, closure);
1436 if(swap) callback(board, flags, WhiteASideCastleFR, 0, ft, 0, ff, closure);
1440 ff = castlingRights[5]; /* King file if we have any rights */
1441 if(ff != NoRights && board[BOARD_HEIGHT-1][ff] == BlackKing) {
1442 ft = castlingRights[3]; /* Rook file if we have H-side rights */
1444 right = BOARD_RGHT-2;
1445 if(ff == BOARD_RGHT-2) left = right = ff-1; /* special case */
1446 for(k=left; k<=right && ft != NoRights; k++) /* first test if blocked */
1447 if(k != ft && board[BOARD_HEIGHT-1][k] != EmptySquare) ft = NoRights;
1448 for(k=left; k<right && ft != NoRights; k++) /* then if not checked */
1449 if(!ignoreCheck && CheckTest(board, flags, BOARD_HEIGHT-1, ff, BOARD_HEIGHT-1, k, FALSE)) ft = NoRights;
1450 if(ft != NoRights && board[BOARD_HEIGHT-1][ft] == BlackRook) {
1451 if(flags & F_FRC_TYPE_CASTLING) callback(board, flags, BlackHSideCastleFR, BOARD_HEIGHT-1, ff, BOARD_HEIGHT-1, ft, closure);
1452 if(swap) callback(board, flags, BlackHSideCastleFR, BOARD_HEIGHT-1, ft, BOARD_HEIGHT-1, ff, closure);
1455 ft = castlingRights[4]; /* Rook file if we have A-side rights */
1456 left = BOARD_LEFT+2;
1458 if(ff <= BOARD_LEFT+2) { left = ff+1; right = BOARD_LEFT+3; }
1459 for(k=left; k<=right && ft != NoRights; k++) /* first test if blocked */
1460 if(k != ft && board[BOARD_HEIGHT-1][k] != EmptySquare) ft = NoRights;
1461 if(ft == 0 && ff != 1 && board[BOARD_HEIGHT-1][1] != EmptySquare) ft = NoRights; /* Rook can be blocked on b8 */
1462 if(ff > BOARD_LEFT+2)
1463 for(k=left+1; k<=right && ft != NoRights; k++) /* then if not checked */
1464 if(!ignoreCheck && CheckTest(board, flags, BOARD_HEIGHT-1, ff, BOARD_HEIGHT-1, k, FALSE)) ft = NoRights;
1465 if(ft != NoRights && board[BOARD_HEIGHT-1][ft] == BlackRook) {
1466 if(flags & F_FRC_TYPE_CASTLING) callback(board, flags, BlackASideCastleFR, BOARD_HEIGHT-1, ff, BOARD_HEIGHT-1, ft, closure);
1467 if(swap) callback(board, flags, BlackASideCastleFR, BOARD_HEIGHT-1, ft, BOARD_HEIGHT-1, ff, closure);
1484 extern void CheckTestCallback P((Board board, int flags, ChessMove kind,
1485 int rf, int ff, int rt, int ft,
1490 CheckTestCallback (Board board, int flags, ChessMove kind, int rf, int ff, int rt, int ft, VOIDSTAR closure)
1492 register CheckTestClosure *cl = (CheckTestClosure *) closure;
1494 if (rt == cl->rking && ft == cl->fking) {
1495 if(xqCheckers[EP_STATUS] >= 2 && xqCheckers[rf][ff]) return; // checker is piece with suspended checking power
1497 xqCheckers[rf][ff] = xqCheckers[EP_STATUS] & 1; // remember who is checking (if status == 1)
1499 if( board[EP_STATUS] == EP_ROYAL_LION && (board[rt][ft] == WhiteLion || board[rt][ft] == BlackLion)
1500 && (gameInfo.variant != VariantLion || board[rf][ff] != WhiteKing && board[rf][ff] != BlackKing) )
1501 cl->check++; // [HGM] lion: forbidden counterstrike against Lion equated to putting yourself in check
1505 /* If the player on move were to move from (rf, ff) to (rt, ft), would
1506 he leave himself in check? Or if rf == -1, is the player on move
1507 in check now? enPassant must be TRUE if the indicated move is an
1508 e.p. capture. The possibility of castling out of a check along the
1509 back rank is not accounted for (i.e., we still return nonzero), as
1510 this is illegal anyway. Return value is the number of times the
1511 king is in check. */
1513 CheckTest (Board board, int flags, int rf, int ff, int rt, int ft, int enPassant)
1515 CheckTestClosure cl;
1516 ChessSquare king = flags & F_WHITE_ON_MOVE ? WhiteKing : BlackKing;
1517 ChessSquare captured = EmptySquare, ep=0, trampled=0;
1518 /* Suppress warnings on uninitialized variables */
1520 if(gameInfo.variant == VariantXiangqi)
1521 king = flags & F_WHITE_ON_MOVE ? WhiteWazir : BlackWazir;
1522 if(gameInfo.variant == VariantKnightmate)
1523 king = flags & F_WHITE_ON_MOVE ? WhiteUnicorn : BlackUnicorn;
1524 if(gameInfo.variant == VariantChu) { // strictly speaking this is not needed, as Chu officially has no check
1525 int r, f, k = king, royals=0, prince = flags & F_WHITE_ON_MOVE ? WhiteMonarch : BlackMonarch;
1526 for(r=0; r<BOARD_HEIGHT; r++) for(f=BOARD_LEFT; f<BOARD_RGHT; f++) {
1527 if(board[r][f] == k || board[r][f] == prince) {
1528 if(++royals > 1) return FALSE; // no check if we have two royals (ignores double captureby Lion!)
1529 king = board[r][f]; // remember hich one we had
1536 captured = board[rf][ft];
1537 board[rf][ft] = EmptySquare;
1539 captured = board[rt][ft];
1540 if(killX >= 0) { trampled = board[killY][killX]; board[killY][killX] = EmptySquare; }
1542 if(rf == DROP_RANK) board[rt][ft] = ff; else { // [HGM] drop
1543 board[rt][ft] = board[rf][ff];
1544 board[rf][ff] = EmptySquare;
1546 ep = board[EP_STATUS];
1547 if( captured == WhiteLion || captured == BlackLion ) { // [HGM] lion: Chu Lion-capture rules
1548 ChessSquare victim = killX < 0 ? EmptySquare : trampled;
1549 if( (board[rt][ft] == WhiteLion || board[rt][ft] == BlackLion) && // capturer is Lion
1550 (ff - ft > 1 || ft - ff > 1 || rf - rt > 1 || rt - rf > 1) && // captures from a distance
1551 (victim == EmptySquare || victim == WhitePawn || victim == BlackPawn) ) // no or worthless 'bridge'
1552 board[EP_STATUS] = EP_ROYAL_LION; // on distant Lion x Lion victim must not be pseudo-legally protected
1556 /* For compatibility with ICS wild 9, we scan the board in the
1557 order a1, a2, a3, ... b1, b2, ..., h8 to find the first king,
1558 and we test only whether that one is in check. */
1559 for (cl.fking = BOARD_LEFT+0; cl.fking < BOARD_RGHT; cl.fking++)
1560 for (cl.rking = 0; cl.rking < BOARD_HEIGHT; cl.rking++) {
1561 if (board[cl.rking][cl.fking] == king) {
1563 if(gameInfo.variant == VariantXiangqi) {
1564 /* [HGM] In Xiangqi opposing Kings means check as well */
1566 dir = (king >= BlackPawn) ? -1 : 1;
1567 for( i=cl.rking+dir; i>=0 && i<BOARD_HEIGHT &&
1568 board[i][cl.fking] == EmptySquare; i+=dir );
1569 if(i>=0 && i<BOARD_HEIGHT &&
1570 board[i][cl.fking] == (dir>0 ? BlackWazir : WhiteWazir) )
1573 GenPseudoLegal(board, flags ^ F_WHITE_ON_MOVE, CheckTestCallback, (VOIDSTAR) &cl, EmptySquare);
1574 if(gameInfo.variant != VariantSpartan || cl.check == 0) // in Spartan Chess go on to test if other King is checked too
1575 goto undo_move; /* 2-level break */
1582 if(rf != DROP_RANK) // [HGM] drop
1583 board[rf][ff] = board[rt][ft];
1585 board[rf][ft] = captured;
1586 board[rt][ft] = EmptySquare;
1588 if(killX >= 0) board[killY][killX] = trampled;
1589 board[rt][ft] = captured;
1591 board[EP_STATUS] = ep;
1594 return cl.fking < BOARD_RGHT ? cl.check : 1000; // [HGM] atomic: return 1000 if we have no king
1598 HasLion (Board board, int flags)
1600 int lion = F_WHITE_ON_MOVE & flags ? WhiteLion : BlackLion;
1602 for(r=0; r<BOARD_HEIGHT; r++) for(f=BOARD_LEFT; f<BOARD_RGHT; f++)
1603 if(board[r][f] == lion) return 1;
1608 LegalDrop (Board board, int flags, ChessSquare piece, int rt, int ft)
1609 { // [HGM] put drop legality testing in separate routine for clarity
1611 if(appData.debugMode) fprintf(debugFP, "LegalDrop: %d @ %d,%d)\n", piece, ft, rt);
1612 if(board[rt][ft] != EmptySquare) return ImpossibleMove; // must drop to empty square
1613 n = PieceToNumber(piece);
1614 if((gameInfo.holdingsWidth == 0 || (flags & F_WHITE_ON_MOVE ? board[n][BOARD_WIDTH-1] : board[BOARD_HEIGHT-1-n][0]) != piece)
1615 && gameInfo.variant != VariantBughouse) // in bughouse we don't check for availability, because ICS doesn't always tell us
1616 return ImpossibleMove; // piece not available
1617 if(gameInfo.variant == VariantShogi) { // in Shogi lots of drops are forbidden!
1618 if((piece == WhitePawn || piece == WhiteQueen) && rt == BOARD_HEIGHT-1 ||
1619 (piece == BlackPawn || piece == BlackQueen) && rt == 0 ||
1620 piece == WhiteKnight && rt > BOARD_HEIGHT-3 ||
1621 piece == BlackKnight && rt < 2 ) return IllegalMove; // e.g. where dropped piece has no moves
1622 if(piece == WhitePawn || piece == BlackPawn) {
1623 int r, max = 1 + (BOARD_HEIGHT == 7); // two Pawns per file in Tori!
1624 for(r=1; r<BOARD_HEIGHT-1; r++)
1625 if(!(max -= (board[r][ft] == piece))) return IllegalMove; // or there already is a Pawn in file
1626 // should still test if we mate with this Pawn
1628 } else if(gameInfo.variant == VariantSChess) { // only back-rank drops
1629 if (rt != (piece < BlackPawn ? 0 : BOARD_HEIGHT-1)) return IllegalMove;
1631 if( (piece == WhitePawn || piece == BlackPawn) &&
1632 (rt == 0 || rt == BOARD_HEIGHT -1 ) )
1633 return IllegalMove; /* no pawn drops on 1st/8th */
1635 if(appData.debugMode) fprintf(debugFP, "LegalDrop: %d @ %d,%d)\n", piece, ft, rt);
1636 if (!(flags & F_IGNORE_CHECK) &&
1637 CheckTest(board, flags, DROP_RANK, piece, rt, ft, FALSE) ) return IllegalMove;
1638 return flags & F_WHITE_ON_MOVE ? WhiteDrop : BlackDrop;
1641 extern void LegalityTestCallback P((Board board, int flags, ChessMove kind,
1642 int rf, int ff, int rt, int ft,
1646 LegalityTestCallback (Board board, int flags, ChessMove kind, int rf, int ff, int rt, int ft, VOIDSTAR closure)
1648 register LegalityTestClosure *cl = (LegalityTestClosure *) closure;
1650 if(board[rt][ft] != EmptySquare || kind==WhiteCapturesEnPassant || kind==BlackCapturesEnPassant)
1651 cl->captures++; // [HGM] losers: count legal captures
1652 if (rf == cl->rf && ff == cl->ff && rt == cl->rt && ft == cl->ft)
1657 LegalityTest (Board board, int flags, int rf, int ff, int rt, int ft, int promoChar)
1659 LegalityTestClosure cl; ChessSquare piece, filterPiece;
1661 if(quickFlag) flags = flags & ~1 | quickFlag & 1; // [HGM] speed: in quick mode quickFlag specifies side-to-move.
1662 if(rf == DROP_RANK) return LegalDrop(board, flags, ff, rt, ft);
1663 piece = filterPiece = board[rf][ff];
1664 if(PieceToChar(piece) == '~') filterPiece = DEMOTED piece;
1666 /* [HGM] Cobra and Falcon are wildcard pieces; consider all their moves legal */
1667 /* (perhaps we should disallow moves that obviously leave us in check?) */
1668 if((piece == WhiteFalcon || piece == BlackFalcon ||
1669 piece == WhiteCobra || piece == BlackCobra) && gameInfo.variant != VariantChu && !pieceDesc[piece])
1670 return CheckTest(board, flags, rf, ff, rt, ft, FALSE) ? IllegalMove : NormalMove;
1674 cl.rt = rFilter = rt; // [HGM] speed: filter on to-square
1675 cl.ft = fFilter = ft;
1676 cl.kind = IllegalMove;
1677 cl.captures = 0; // [HGM] losers: prepare to count legal captures.
1678 if(flags & F_MANDATORY_CAPTURE) filterPiece = EmptySquare; // [HGM] speed: do not filter in suicide, to find all captures
1679 GenLegal(board, flags, LegalityTestCallback, (VOIDSTAR) &cl, filterPiece);
1680 if((flags & F_MANDATORY_CAPTURE) && cl.captures && board[rt][ft] == EmptySquare
1681 && cl.kind != WhiteCapturesEnPassant && cl.kind != BlackCapturesEnPassant)
1682 return(IllegalMove); // [HGM] losers: if there are legal captures, non-capts are illegal
1684 if(promoChar == 'x') promoChar = NULLCHAR; // [HGM] is this ever the case?
1685 if(gameInfo.variant == VariantSChess && promoChar && promoChar != '=' && board[rf][ff] != WhitePawn && board[rf][ff] != BlackPawn) {
1686 if(board[rf][ff] < BlackPawn) { // white
1687 if(rf != 0) return IllegalMove; // must be on back rank
1688 if(!(board[VIRGIN][ff] & VIRGIN_W)) return IllegalMove; // non-virgin
1689 if(board[PieceToNumber(CharToPiece(ToUpper(promoChar)))][BOARD_WIDTH-2] == 0) return ImpossibleMove;// must be in stock
1690 if(cl.kind == WhiteHSideCastleFR && (ff == BOARD_RGHT-2 || ff == BOARD_RGHT-3)) return ImpossibleMove;
1691 if(cl.kind == WhiteASideCastleFR && (ff == BOARD_LEFT+2 || ff == BOARD_LEFT+3)) return ImpossibleMove;
1693 if(rf != BOARD_HEIGHT-1) return IllegalMove;
1694 if(!(board[VIRGIN][ff] & VIRGIN_B)) return IllegalMove; // non-virgin
1695 if(board[BOARD_HEIGHT-1-PieceToNumber(CharToPiece(ToLower(promoChar)))][1] == 0) return ImpossibleMove;
1696 if(cl.kind == BlackHSideCastleFR && (ff == BOARD_RGHT-2 || ff == BOARD_RGHT-3)) return ImpossibleMove;
1697 if(cl.kind == BlackASideCastleFR && (ff == BOARD_LEFT+2 || ff == BOARD_LEFT+3)) return ImpossibleMove;
1700 if(gameInfo.variant == VariantChu) {
1701 if(cl.kind != NormalMove || promoChar == NULLCHAR || promoChar == '=') return cl.kind;
1702 if(promoChar != '+')
1703 return CharToPiece(promoChar) == EmptySquare ? ImpossibleMove : IllegalMove;
1704 if(PieceToChar(CHUPROMOTED board[rf][ff]) != '+') return ImpossibleMove;
1705 return flags & F_WHITE_ON_MOVE ? WhitePromotion : BlackPromotion;
1707 if(gameInfo.variant == VariantShogi) {
1708 /* [HGM] Shogi promotions. '=' means defer */
1709 if(rf != DROP_RANK && cl.kind == NormalMove) {
1710 ChessSquare piece = board[rf][ff];
1712 if(promoChar == PieceToChar(BlackQueen)) promoChar = NULLCHAR; /* [HGM] Kludge */
1713 if(promoChar == 'd' && (piece == WhiteRook || piece == BlackRook) ||
1714 promoChar == 'h' && (piece == WhiteBishop || piece == BlackBishop) ||
1715 promoChar == 'g' && (piece <= WhiteFerz || piece <= BlackFerz && piece >= BlackPawn) )
1716 promoChar = '+'; // allowed ICS notations
1717 if(appData.debugMode)fprintf(debugFP,"SHOGI promoChar = %c\n", promoChar ? promoChar : '-');
1718 if(promoChar != NULLCHAR && promoChar != '+' && promoChar != '=')
1719 return CharToPiece(promoChar) == EmptySquare ? ImpossibleMove : IllegalMove;
1720 else if(flags & F_WHITE_ON_MOVE) {
1721 if( (int) piece < (int) WhiteWazir &&
1722 (rf >= BOARD_HEIGHT - BOARD_HEIGHT/3 || rt >= BOARD_HEIGHT - BOARD_HEIGHT/3) ) {
1723 if( (piece == WhitePawn || piece == WhiteQueen) && rt > BOARD_HEIGHT-2 ||
1724 piece == WhiteKnight && rt > BOARD_HEIGHT-3) /* promotion mandatory */
1725 cl.kind = promoChar == '=' ? IllegalMove : WhitePromotion;
1726 else /* promotion optional, default is defer */
1727 cl.kind = promoChar == '+' ? WhitePromotion : WhiteNonPromotion;
1728 } else cl.kind = promoChar == '+' ? IllegalMove : NormalMove;
1730 if( (int) piece < (int) BlackWazir && (rf < BOARD_HEIGHT/3 || rt < BOARD_HEIGHT/3) ) {
1731 if( (piece == BlackPawn || piece == BlackQueen) && rt < 1 ||
1732 piece == BlackKnight && rt < 2 ) /* promotion obligatory */
1733 cl.kind = promoChar == '=' ? IllegalMove : BlackPromotion;
1734 else /* promotion optional, default is defer */
1735 cl.kind = promoChar == '+' ? BlackPromotion : BlackNonPromotion;
1736 } else cl.kind = promoChar == '+' ? IllegalMove : NormalMove;
1740 if (promoChar != NULLCHAR) {
1741 if(cl.kind == NormalMove && promoChar == '+') { // allow shogi-style promotion is pieceToChar specifies them
1742 ChessSquare piece = board[rf][ff];
1743 if(piece < BlackPawn ? piece > WhiteMan : piece > BlackMan) return ImpossibleMove; // already promoted
1744 // should test if in zone, really
1745 if(gameInfo.variant == VariantChuChess && (piece == WhiteKnight || piece == BlackKnight) && HasLion(board, flags))
1747 if(PieceToChar(PROMOTED piece) == '+') return flags & F_WHITE_ON_MOVE ? WhitePromotion : BlackPromotion;
1749 if(promoChar == '=') cl.kind = IllegalMove; else // [HGM] shogi: no deferred promotion outside Shogi
1750 if (cl.kind == WhitePromotion || cl.kind == BlackPromotion) {
1751 ChessSquare piece = CharToPiece(flags & F_WHITE_ON_MOVE ? ToUpper(promoChar) : ToLower(promoChar));
1752 if(piece == EmptySquare)
1753 cl.kind = ImpossibleMove; // non-existing piece
1754 if(gameInfo.variant == VariantChuChess && promoChar == 'l' && HasLion(board, flags)) {
1755 cl.kind = IllegalMove; // no two Lions
1756 } else if(gameInfo.variant == VariantSpartan && cl.kind == BlackPromotion ) {
1757 if(promoChar != PieceToChar(BlackKing)) {
1758 if(CheckTest(board, flags, rf, ff, rt, ft, FALSE)) cl.kind = IllegalMove; // [HGM] spartan: only promotion to King was possible
1759 if(piece == BlackLance) cl.kind = ImpossibleMove;
1760 } else { // promotion to King allowed only if we do not have two yet
1761 int r, f, kings = 0;
1762 for(r=0; r<BOARD_HEIGHT; r++) for(f=BOARD_LEFT; f<BOARD_RGHT; f++) kings += (board[r][f] == BlackKing);
1763 if(kings == 2) cl.kind = IllegalMove;
1765 } else if(piece == WhitePawn && rt == BOARD_HEIGHT-1 ||
1766 piece == BlackPawn && rt == 0) cl.kind = IllegalMove; // cannot stay Pawn on last rank in any variant
1767 else if((piece == WhiteUnicorn || piece == BlackUnicorn) && gameInfo.variant == VariantKnightmate)
1768 cl.kind = IllegalMove; // promotion to Royal Knight not allowed
1769 else if((piece == WhiteKing || piece == BlackKing) && gameInfo.variant != VariantSuicide && gameInfo.variant != VariantGiveaway)
1770 cl.kind = IllegalMove; // promotion to King usually not allowed
1772 cl.kind = IllegalMove;
1782 extern void MateTestCallback P((Board board, int flags, ChessMove kind,
1783 int rf, int ff, int rt, int ft,
1787 MateTestCallback (Board board, int flags, ChessMove kind, int rf, int ff, int rt, int ft, VOIDSTAR closure)
1789 register MateTestClosure *cl = (MateTestClosure *) closure;
1794 /* Return MT_NONE, MT_CHECK, MT_CHECKMATE, or MT_STALEMATE */
1796 MateTest (Board board, int flags)
1799 int inCheck, r, f, myPieces=0, hisPieces=0, nrKing=0;
1800 ChessSquare king = flags & F_WHITE_ON_MOVE ? WhiteKing : BlackKing;
1802 for(r=0; r<BOARD_HEIGHT; r++) for(f=BOARD_LEFT; f<BOARD_RGHT; f++) {
1803 // [HGM] losers: Count pieces and kings, to detect other unorthodox winning conditions
1804 nrKing += (board[r][f] == king); // stm has king
1805 if( board[r][f] != EmptySquare ) {
1806 if((int)board[r][f] <= (int)king && (int)board[r][f] >= (int)king - (int)WhiteKing + (int)WhitePawn)
1811 switch(gameInfo.variant) { // [HGM] losers: extinction wins
1812 case VariantShatranj:
1813 if(hisPieces == 1) return myPieces > 1 ? MT_BARE : MT_DRAW;
1817 if(nrKing == 0) return MT_NOKING;
1820 if(myPieces == 1) return MT_BARE;
1823 inCheck = GenLegal(board, flags, MateTestCallback, (VOIDSTAR) &cl, EmptySquare);
1824 // [HGM] 3check: yet to do!
1826 return inCheck ? MT_CHECK : MT_NONE;
1828 if(gameInfo.holdingsWidth && gameInfo.variant != VariantSuper && gameInfo.variant != VariantGreat
1829 && gameInfo.variant != VariantSChess && gameInfo.variant != VariantGrand) { // drop game
1830 int r, f, n, holdings = flags & F_WHITE_ON_MOVE ? BOARD_WIDTH-1 : 0;
1831 for(r=0; r<BOARD_HEIGHT; r++) for(f=BOARD_LEFT; f<BOARD_RGHT; f++) if(board[r][f] == EmptySquare) // all empty squares
1832 for(n=0; n<BOARD_HEIGHT; n++) // all pieces in hand
1833 if(board[n][holdings] != EmptySquare) {
1834 int moveType = LegalDrop(board, flags, board[n][holdings], r, f);
1835 if(moveType == WhiteDrop || moveType == BlackDrop) return (inCheck ? MT_CHECK : MT_NONE); // we have legal drop
1838 if(gameInfo.variant == VariantSuicide) // [HGM] losers: always stalemate, since no check, but result varies
1839 return myPieces == hisPieces ? MT_STALEMATE :
1840 myPieces > hisPieces ? MT_STAINMATE : MT_STEALMATE;
1841 else if(gameInfo.variant == VariantLosers) return inCheck ? MT_TRICKMATE : MT_STEALMATE;
1842 else if(gameInfo.variant == VariantGiveaway) return MT_STEALMATE; // no check exists, stalemated = win
1844 return inCheck ? MT_CHECKMATE
1845 : (gameInfo.variant == VariantXiangqi || gameInfo.variant == VariantShatranj || IS_SHOGI(gameInfo.variant)) ?
1846 MT_STAINMATE : MT_STALEMATE;
1851 extern void DisambiguateCallback P((Board board, int flags, ChessMove kind,
1852 int rf, int ff, int rt, int ft,
1856 DisambiguateCallback (Board board, int flags, ChessMove kind, int rf, int ff, int rt, int ft, VOIDSTAR closure)
1858 register DisambiguateClosure *cl = (DisambiguateClosure *) closure;
1859 int wildCard = FALSE; ChessSquare piece = board[rf][ff];
1861 // [HGM] wild: for wild-card pieces rt and rf are dummies
1862 if(piece == WhiteFalcon || piece == BlackFalcon ||
1863 piece == WhiteCobra || piece == BlackCobra)
1866 if ((cl->pieceIn == EmptySquare || cl->pieceIn == board[rf][ff]
1867 || PieceToChar(board[rf][ff]) == '~'
1868 && cl->pieceIn == (ChessSquare)(DEMOTED board[rf][ff])
1870 (cl->rfIn == -1 || cl->rfIn == rf) &&
1871 (cl->ffIn == -1 || cl->ffIn == ff) &&
1872 (cl->rtIn == -1 || cl->rtIn == rt || wildCard) &&
1873 (cl->ftIn == -1 || cl->ftIn == ft || wildCard)) {
1875 if(cl->count && rf == cl->rf && ff == cl->ff) return; // duplicate move
1878 if(cl->count == 1 || board[rt][ft] != EmptySquare) {
1879 // [HGM] oneclick: if multiple moves, be sure we remember capture
1880 cl->piece = board[rf][ff];
1883 cl->rt = wildCard ? cl->rtIn : rt;
1884 cl->ft = wildCard ? cl->ftIn : ft;
1887 cl->captures += (board[rt][ft] != EmptySquare); // [HGM] oneclick: count captures
1892 Disambiguate (Board board, int flags, DisambiguateClosure *closure)
1894 int illegal = 0; char c = closure->promoCharIn;
1896 if(quickFlag) flags = flags & ~1 | quickFlag & 1; // [HGM] speed: in quick mode quickFlag specifies side-to-move.
1897 closure->count = closure->captures = 0;
1898 closure->rf = closure->ff = closure->rt = closure->ft = 0;
1899 closure->kind = ImpossibleMove;
1900 rFilter = closure->rtIn; // [HGM] speed: only consider moves to given to-square
1901 fFilter = closure->ftIn;
1902 if(quickFlag) { // [HGM] speed: try without check test first, because if that is not ambiguous, we are happy
1903 GenLegal(board, flags|F_IGNORE_CHECK, DisambiguateCallback, (VOIDSTAR) closure, closure->pieceIn);
1904 if(closure->count > 1) { // gamble did not pay off. retry with check test to resolve ambiguity
1905 closure->count = closure->captures = 0;
1906 closure->rf = closure->ff = closure->rt = closure->ft = 0;
1907 closure->kind = ImpossibleMove;
1908 GenLegal(board, flags, DisambiguateCallback, (VOIDSTAR) closure, closure->pieceIn); // [HGM] speed: only pieces of requested type
1911 GenLegal(board, flags, DisambiguateCallback, (VOIDSTAR) closure, closure->pieceIn); // [HGM] speed: only pieces of requested type
1912 if (closure->count == 0) {
1913 /* See if it's an illegal move due to check */
1915 GenLegal(board, flags|F_IGNORE_CHECK, DisambiguateCallback, (VOIDSTAR) closure, closure->pieceIn);
1916 if (closure->count == 0) {
1917 /* No, it's not even that */
1918 if(!appData.testLegality && closure->pieceIn != EmptySquare) {
1919 int f, r; // if there is only a single piece of the requested type on the board, use that
1920 closure->rt = closure->rtIn, closure->ft = closure->ftIn;
1921 for(r=0; r<BOARD_HEIGHT; r++) for(f=BOARD_LEFT; f<BOARD_RGHT; f++)
1922 if(board[r][f] == closure->pieceIn) closure->count++, closure->rf = r, closure->ff = f;
1923 if(closure->count > 1) illegal = 0; // ambiguous
1925 if(closure->count == 0) {
1926 if (appData.debugMode) { int i, j;
1927 for(i=BOARD_HEIGHT-1; i>=0; i--) {
1928 for(j=0; j<BOARD_WIDTH; j++)
1929 fprintf(debugFP, "%3d", (int) board[i][j]);
1930 fprintf(debugFP, "\n");
1936 } else if(pieceDefs && closure->count > 1) { // [HGM] gen: move is ambiguous under engine-defined rules
1937 DisambiguateClosure spare = *closure;
1938 pieceDefs = FALSE; spare.count = 0; // See if the (erroneous) built-in rules would resolve that
1939 GenLegal(board, flags, DisambiguateCallback, (VOIDSTAR) &spare, closure->pieceIn);
1940 if(spare.count == 1) *closure = spare; // It does, so use those in stead (game from file saved before gen patch?)
1944 if (c == 'x') c = NULLCHAR; // get rid of any 'x' (which should never happen?)
1945 if(gameInfo.variant == VariantSChess && c && c != '=' && closure->piece != WhitePawn && closure->piece != BlackPawn) {
1946 if(closure->piece < BlackPawn) { // white
1947 if(closure->rf != 0) closure->kind = IllegalMove; // must be on back rank
1948 if(!(board[VIRGIN][closure->ff] & VIRGIN_W)) closure->kind = IllegalMove; // non-virgin
1949 if(board[PieceToNumber(CharToPiece(ToUpper(c)))][BOARD_WIDTH-2] == 0) closure->kind = ImpossibleMove;// must be in stock
1950 if(closure->kind == WhiteHSideCastleFR && (closure->ff == BOARD_RGHT-2 || closure->ff == BOARD_RGHT-3)) closure->kind = ImpossibleMove;
1951 if(closure->kind == WhiteASideCastleFR && (closure->ff == BOARD_LEFT+2 || closure->ff == BOARD_LEFT+3)) closure->kind = ImpossibleMove;
1953 if(closure->rf != BOARD_HEIGHT-1) closure->kind = IllegalMove;
1954 if(!(board[VIRGIN][closure->ff] & VIRGIN_B)) closure->kind = IllegalMove; // non-virgin
1955 if(board[BOARD_HEIGHT-1-PieceToNumber(CharToPiece(ToLower(c)))][1] == 0) closure->kind = ImpossibleMove;
1956 if(closure->kind == BlackHSideCastleFR && (closure->ff == BOARD_RGHT-2 || closure->ff == BOARD_RGHT-3)) closure->kind = ImpossibleMove;
1957 if(closure->kind == BlackASideCastleFR && (closure->ff == BOARD_LEFT+2 || closure->ff == BOARD_LEFT+3)) closure->kind = ImpossibleMove;
1960 if(gameInfo.variant == VariantChu) {
1961 if(c == '+') closure->kind = (flags & F_WHITE_ON_MOVE ? WhitePromotion : BlackPromotion); // for now, accept any
1963 if(gameInfo.variant == VariantShogi) {
1964 /* [HGM] Shogi promotions. On input, '=' means defer, '+' promote. Afterwards, c is set to '+' for promotions, NULL other */
1965 if(closure->rfIn != DROP_RANK && closure->kind == NormalMove) {
1966 ChessSquare piece = closure->piece;
1967 if (c == 'd' && (piece == WhiteRook || piece == BlackRook) ||
1968 c == 'h' && (piece == WhiteBishop || piece == BlackBishop) ||
1969 c == 'g' && (piece <= WhiteFerz || piece <= BlackFerz && piece >= BlackPawn) )
1970 c = '+'; // allowed ICS notations
1971 if(c != NULLCHAR && c != '+' && c != '=') closure->kind = IllegalMove; // otherwise specifying a piece is illegal
1972 else if(flags & F_WHITE_ON_MOVE) {
1973 if( (int) piece < (int) WhiteWazir &&
1974 (closure->rf >= BOARD_HEIGHT-(BOARD_HEIGHT/3) || closure->rt >= BOARD_HEIGHT-(BOARD_HEIGHT/3)) ) {
1975 if( (piece == WhitePawn || piece == WhiteQueen) && closure->rt > BOARD_HEIGHT-2 ||
1976 piece == WhiteKnight && closure->rt > BOARD_HEIGHT-3) /* promotion mandatory */
1977 closure->kind = c == '=' ? IllegalMove : WhitePromotion;
1978 else /* promotion optional, default is defer */
1979 closure->kind = c == '+' ? WhitePromotion : WhiteNonPromotion;
1980 } else closure->kind = c == '+' ? IllegalMove : NormalMove;
1982 if( (int) piece < (int) BlackWazir && (closure->rf < BOARD_HEIGHT/3 || closure->rt < BOARD_HEIGHT/3) ) {
1983 if( (piece == BlackPawn || piece == BlackQueen) && closure->rt < 1 ||
1984 piece == BlackKnight && closure->rt < 2 ) /* promotion obligatory */
1985 closure->kind = c == '=' ? IllegalMove : BlackPromotion;
1986 else /* promotion optional, default is defer */
1987 closure->kind = c == '+' ? BlackPromotion : BlackNonPromotion;
1988 } else closure->kind = c == '+' ? IllegalMove : NormalMove;
1991 if(closure->kind == WhitePromotion || closure->kind == BlackPromotion) c = '+'; else
1992 if(closure->kind == WhiteNonPromotion || closure->kind == BlackNonPromotion) c = '=';
1994 if (closure->kind == WhitePromotion || closure->kind == BlackPromotion) {
1995 if(c == NULLCHAR) { // missing promoChar on mandatory promotion; use default for variant
1996 if(gameInfo.variant == VariantShatranj || gameInfo.variant == VariantCourier ||
1997 gameInfo.variant == VariantMakruk || gameInfo.variant == VariantASEAN)
1998 c = PieceToChar(BlackFerz);
1999 else if(gameInfo.variant == VariantGreat)
2000 c = PieceToChar(BlackMan);
2001 else if(gameInfo.variant == VariantGrand)
2002 closure->kind = closure->rt != 0 && closure->rt != BOARD_HEIGHT-1 ? NormalMove : AmbiguousMove; // no default in Grand Chess
2004 c = PieceToChar(BlackQueen);
2005 } else if(c == '=') closure->kind = IllegalMove; // no deferral outside Shogi
2006 else if(c == 'l' && gameInfo.variant == VariantChuChess && HasLion(board, flags)) closure->kind = IllegalMove;
2007 } else if (c == '+') { // '+' outside shogi, check if pieceToCharTable enabled it
2008 ChessSquare p = closure->piece;
2009 if(p > WhiteMan && p < BlackPawn || p > BlackMan || PieceToChar(PROMOTED p) != '+')
2010 closure->kind = ImpossibleMove; // used on non-promotable piece
2011 else if(gameInfo.variant == VariantChuChess && HasLion(board, flags)) closure->kind = IllegalMove;
2012 } else if (c != NULLCHAR) closure->kind = IllegalMove;
2014 closure->promoChar = ToLower(c); // this can be NULLCHAR! Note we keep original promoChar even if illegal.
2015 if(c != '+' && c != '=' && c != NULLCHAR && CharToPiece(flags & F_WHITE_ON_MOVE ? ToUpper(c) : ToLower(c)) == EmptySquare)
2016 closure->kind = ImpossibleMove; // but we cannot handle non-existing piece types!
2017 if (closure->count > 1) {
2018 closure->kind = AmbiguousMove;
2021 /* Note: If more than one illegal move matches, but no legal
2022 moves, we return IllegalMove, not AmbiguousMove. Caller
2023 can look at closure->count to detect this.
2025 closure->kind = IllegalMove;
2039 } CoordsToAlgebraicClosure;
2041 extern void CoordsToAlgebraicCallback P((Board board, int flags,
2042 ChessMove kind, int rf, int ff,
2043 int rt, int ft, VOIDSTAR closure));
2046 CoordsToAlgebraicCallback (Board board, int flags, ChessMove kind, int rf, int ff, int rt, int ft, VOIDSTAR closure)
2048 register CoordsToAlgebraicClosure *cl =
2049 (CoordsToAlgebraicClosure *) closure;
2051 if ((rt == cl->rt && ft == cl->ft || rt == rf && ft == ff) && // [HGM] null move matches any toSquare
2052 (board[rf][ff] == cl->piece
2053 || PieceToChar(board[rf][ff]) == '~' &&
2054 (ChessSquare) (DEMOTED board[rf][ff]) == cl->piece)
2058 cl->kind = kind; /* this is the move we want */
2060 cl->file++; /* need file to rule out this move */
2064 cl->rank++; /* need rank to rule out this move */
2066 cl->either++; /* rank or file will rule out this move */
2072 /* Convert coordinates to normal algebraic notation.
2073 promoChar must be NULLCHAR or 'x' if not a promotion.
2076 CoordsToAlgebraic (Board board, int flags, int rf, int ff, int rt, int ft, int promoChar, char out[MOVE_LEN])
2080 char *outp = out, c, capture;
2081 CoordsToAlgebraicClosure cl;
2083 if (rf == DROP_RANK) {
2084 if(ff == EmptySquare) { strncpy(outp, "--",3); return NormalMove; } // [HGM] pass
2085 /* Bughouse piece drop */
2086 *outp++ = ToUpper(PieceToChar((ChessSquare) ff));
2091 else { *outp++ = (rt+ONE-'0')/10 + '0';*outp++ = (rt+ONE-'0')%10 + '0'; }
2093 return (flags & F_WHITE_ON_MOVE) ? WhiteDrop : BlackDrop;
2096 if (promoChar == 'x') promoChar = NULLCHAR;
2097 piece = board[rf][ff];
2098 if(PieceToChar(piece)=='~') piece = (ChessSquare)(DEMOTED piece);
2103 kind = LegalityTest(board, flags, rf, ff, rt, ft, promoChar);
2104 if (kind == IllegalMove && !(flags&F_IGNORE_CHECK)) {
2105 /* Keep short notation if move is illegal only because it
2106 leaves the player in check, but still return IllegalMove */
2107 kind = LegalityTest(board, flags|F_IGNORE_CHECK, rf, ff, rt, ft, promoChar);
2108 if (kind == IllegalMove) break;
2113 capture = board[rt][ft] != EmptySquare || kind == WhiteCapturesEnPassant || kind == BlackCapturesEnPassant;
2114 if (ff == ft && !capture) { /* [HGM] Xiangqi has straight noncapts! */
2115 /* Non-capture; use style "e5" */
2118 else { *outp++ = (rt+ONE-'0')/10 + '0';*outp++ = (rt+ONE-'0')%10 + '0'; }
2120 /* Capture; use style "exd5" */
2122 *outp++ = 'x'; /* [HGM] Xiangqi has sideway noncaptures across river! */
2126 else { *outp++ = (rt+ONE-'0')/10 + '0';*outp++ = (rt+ONE-'0')%10 + '0'; }
2128 /* Use promotion suffix style "=Q" */
2130 if (promoChar != NULLCHAR) {
2131 if(IS_SHOGI(gameInfo.variant)) {
2132 /* [HGM] ... but not in Shogi! */
2133 *outp++ = promoChar == '=' ? '=' : '+';
2136 *outp++ = ToUpper(promoChar);
2145 /* Fabien moved code: FRC castling first (if KxR), wild castling second */
2146 /* Code added by Tord: FRC castling. */
2147 if((piece == WhiteKing && board[rt][ft] == WhiteRook) ||
2148 (piece == BlackKing && board[rt][ft] == BlackRook)) {
2150 safeStrCpy(out, "O-O", MOVE_LEN);
2152 safeStrCpy(out, "O-O-O", MOVE_LEN);
2153 return LegalityTest(board, flags, rf, ff, rt, ft, promoChar);
2155 /* End of code added by Tord */
2156 /* Test for castling or ICS wild castling */
2157 /* Use style "O-O" (oh-oh) for PGN compatibility */
2158 else if (rf == rt &&
2159 rf == ((piece == WhiteKing) ? 0 : BOARD_HEIGHT-1) &&
2160 (ft - ff > 1 || ff - ft > 1) && // No castling if legal King move (on narrow boards!)
2161 ((ff == BOARD_WIDTH>>1 && (ft == BOARD_LEFT+2 || ft == BOARD_RGHT-2)) ||
2162 (ff == (BOARD_WIDTH-1)>>1 && (ft == BOARD_LEFT+1 || ft == BOARD_RGHT-3)))) {
2163 if(ft==BOARD_LEFT+1 || ft==BOARD_RGHT-2)
2164 snprintf(out, MOVE_LEN, "O-O%c%c", promoChar ? '/' : 0, ToUpper(promoChar));
2166 snprintf(out, MOVE_LEN, "O-O-O%c%c", promoChar ? '/' : 0, ToUpper(promoChar));
2168 /* This notation is always unambiguous, unless there are
2169 kings on both the d and e files, with "wild castling"
2170 possible for the king on the d file and normal castling
2171 possible for the other. ICS rules for wild 9
2172 effectively make castling illegal for either king in
2173 this situation. So I am not going to worry about it;
2174 I'll just generate an ambiguous O-O in this case.
2176 return LegalityTest(board, flags, rf, ff, rt, ft, promoChar);
2179 /* else fall through */
2184 cl.rt = rFilter = rt; // [HGM] speed: filter on to-square
2185 cl.ft = fFilter = ft;
2187 cl.kind = IllegalMove;
2188 cl.rank = cl.file = cl.either = 0;
2189 c = PieceToChar(piece) ;
2190 GenLegal(board, flags, CoordsToAlgebraicCallback, (VOIDSTAR) &cl, c!='~' ? piece : (DEMOTED piece)); // [HGM] speed
2192 if (cl.kind == IllegalMove && !(flags&F_IGNORE_CHECK)) {
2193 /* Generate pretty moves for moving into check, but
2194 still return IllegalMove.
2196 GenLegal(board, flags|F_IGNORE_CHECK, CoordsToAlgebraicCallback, (VOIDSTAR) &cl, c!='~' ? piece : (DEMOTED piece));
2197 if (cl.kind == IllegalMove) break;
2198 cl.kind = IllegalMove;
2201 /* Style is "Nf3" or "Nxf7" if this is unambiguous,
2202 else "Ngf3" or "Ngxf7",
2203 else "N1f3" or "N5xf7",
2204 else "Ng1f3" or "Ng5xf7".
2206 if( c == '~' || c == '+') {
2207 /* [HGM] print nonexistent piece as its demoted version */
2208 piece = (ChessSquare) (DEMOTED piece - 11*(gameInfo.variant == VariantChu));
2210 if(c=='+') *outp++ = c;
2211 *outp++ = ToUpper(PieceToChar(piece));
2213 if (cl.file || (cl.either && !cl.rank)) {
2219 else { *outp++ = (rf+ONE-'0')/10 + '0';*outp++ = (rf+ONE-'0')%10 + '0'; }
2222 if(board[rt][ft] != EmptySquare)
2228 else { *outp++ = (rt+ONE-'0')/10 + '0';*outp++ = (rt+ONE-'0')%10 + '0'; }
2229 if (IS_SHOGI(gameInfo.variant)) {
2230 /* [HGM] in Shogi non-pawns can promote */
2231 *outp++ = promoChar; // Don't bother to correct move type, return value is never used!
2233 else if (gameInfo.variant == VariantChuChess && promoChar ||
2234 gameInfo.variant != VariantSuper && promoChar &&
2235 (piece == WhiteLance || piece == BlackLance) ) { // Lance sometimes represents Pawn
2237 *outp++ = ToUpper(promoChar);
2239 else if (gameInfo.variant == VariantSChess && promoChar) { // and in S-Chess we have gating
2241 *outp++ = ToUpper(promoChar);
2247 /* Moving a nonexistent piece */
2251 /* Not a legal move, even ignoring check.
2252 If there was a piece on the from square,
2253 use style "Ng1g3" or "Ng1xe8";
2254 if there was a pawn or nothing (!),
2255 use style "g1g3" or "g1xe8". Use "x"
2256 if a piece was on the to square, even
2257 a piece of the same color.
2261 if (piece != EmptySquare && piece != WhitePawn && piece != BlackPawn) {
2263 for(r=0; r<BOARD_HEIGHT; r++) for(f=BOARD_LEFT; f<=BOARD_RGHT; f++)
2264 c += (board[r][f] == piece); // count on-board pieces of given type
2265 *outp++ = ToUpper(PieceToChar(piece));
2267 if(c != 1) { // [HGM] but if there is only one piece of the mentioned type, no from-square, thank you!
2271 else { *outp++ = (rf+ONE-'0')/10 + '0';*outp++ = (rf+ONE-'0')%10 + '0'; }
2273 if (board[rt][ft] != EmptySquare) *outp++ = 'x';
2277 else { *outp++ = (rt+ONE-'0')/10 + '0';*outp++ = (rt+ONE-'0')%10 + '0'; }
2278 /* Use promotion suffix style "=Q" */
2279 if (promoChar != NULLCHAR && promoChar != 'x') {
2281 *outp++ = ToUpper(promoChar);
2288 // [HGM] XQ: the following code serves to detect perpetual chasing (Asian rules)
2297 // I guess the following variables logically belong in the closure too, but I was too lazy and used globals
2299 int preyStackPointer, chaseStackPointer;
2302 unsigned char rf, ff, rt, ft;
2306 unsigned char rank, file;
2312 // there are three new callbacks for use with GenLegal: for adding captures, deleting them, and finding a recapture
2314 extern void AtacksCallback P((Board board, int flags, ChessMove kind,
2315 int rf, int ff, int rt, int ft,
2319 AttacksCallback (Board board, int flags, ChessMove kind, int rf, int ff, int rt, int ft, VOIDSTAR closure)
2320 { // For adding captures that can lead to chase indictment to the chaseStack
2321 if(board[rt][ft] == EmptySquare) return; // non-capture
2322 if(board[rt][ft] == WhitePawn && rt < BOARD_HEIGHT/2) return; // Pawn before river can be chased
2323 if(board[rt][ft] == BlackPawn && rt >= BOARD_HEIGHT/2) return; // Pawn before river can be chased
2324 if(board[rf][ff] == WhitePawn || board[rf][ff] == BlackPawn) return; // Pawns are allowed to chase
2325 if(board[rf][ff] == WhiteWazir || board[rf][ff] == BlackWazir) return; // King is allowed to chase
2326 // move cannot be excluded from being a chase trivially (based on attacker and victim); save it on chaseStack
2327 chaseStack[chaseStackPointer].rf = rf;
2328 chaseStack[chaseStackPointer].ff = ff;
2329 chaseStack[chaseStackPointer].rt = rt;
2330 chaseStack[chaseStackPointer].ft = ft;
2331 chaseStackPointer++;
2334 extern void ExistingAtacksCallback P((Board board, int flags, ChessMove kind,
2335 int rf, int ff, int rt, int ft,
2339 ExistingAttacksCallback (Board board, int flags, ChessMove kind, int rf, int ff, int rt, int ft, VOIDSTAR closure)
2340 { // for removing pre-exsting captures from the chaseStack, to be left with newly created ones
2342 register ChaseClosure *cl = (ChaseClosure *) closure; //closure tells us the move played in the repeat loop
2344 if(board[rt][ft] == EmptySquare) return; // no capture
2345 if(rf == cl->rf && ff == cl->ff) { // attacks with same piece from new position are not considered new
2346 rf = cl->rt; ff = cl->ft; // doctor their fromSquare so they will be recognized in chaseStack
2348 // search move in chaseStack, and delete it if it occurred there (as we know now it is not a new capture)
2349 for(i=0; i<chaseStackPointer; i++) {
2350 if(chaseStack[i].rf == rf && chaseStack[i].ff == ff &&
2351 chaseStack[i].rt == rt && chaseStack[i].ft == ft ) {
2352 // move found on chaseStack, delete it by overwriting with move popped from top of chaseStack
2353 chaseStack[i] = chaseStack[--chaseStackPointer];
2359 extern void ProtectedCallback P((Board board, int flags, ChessMove kind,
2360 int rf, int ff, int rt, int ft,
2364 ProtectedCallback (Board board, int flags, ChessMove kind, int rf, int ff, int rt, int ft, VOIDSTAR closure)
2365 { // for determining if a piece (given through the closure) is protected
2366 register ChaseClosure *cl = (ChaseClosure *) closure; // closure tells us where to recapture
2368 if(rt == cl->rt && ft == cl->ft) cl->recaptures++; // count legal recaptures to this square
2369 if(appData.debugMode && board[rt][ft] != EmptySquare)
2370 fprintf(debugFP, "try %c%c%c%c=%d\n", ff+AAA, rf+ONE,ft+AAA, rt+ONE, cl->recaptures);
2373 extern char moveList[MAX_MOVES][MOVE_LEN];
2376 PerpetualChase (int first, int last)
2377 { // this routine detects if the side to move in the 'first' position is perpetually chasing (when not checking)
2380 ChessSquare captured;
2382 preyStackPointer = 0; // clear stack of chased pieces
2383 for(i=first; i<last; i+=2) { // for all positions with same side to move
2384 if(appData.debugMode) fprintf(debugFP, "judge position %i\n", i);
2385 chaseStackPointer = 0; // clear stack that is going to hold possible chases
2386 // determine all captures possible after the move, and put them on chaseStack
2387 GenLegal(boards[i+1], PosFlags(i), AttacksCallback, &cl, EmptySquare);
2388 if(appData.debugMode) { int n;
2389 for(n=0; n<chaseStackPointer; n++)
2390 fprintf(debugFP, "%c%c%c%c ", chaseStack[n].ff+AAA, chaseStack[n].rf+ONE,
2391 chaseStack[n].ft+AAA, chaseStack[n].rt+ONE);
2392 fprintf(debugFP, ": all capts\n");
2394 // determine all captures possible before the move, and delete them from chaseStack
2395 cl.rf = moveList[i][1]-ONE; // prepare closure to pass move that led from i to i+1
2396 cl.ff = moveList[i][0]-AAA+BOARD_LEFT;
2397 cl.rt = moveList[i][3]-ONE;
2398 cl.ft = moveList[i][2]-AAA+BOARD_LEFT;
2399 CopyBoard(xqCheckers, nullBoard); xqCheckers[EP_STATUS] = 1; // giant kludge to make GenLegal ignore pre-existing checks
2400 GenLegal(boards[i], PosFlags(i), ExistingAttacksCallback, &cl, EmptySquare);
2401 xqCheckers[EP_STATUS] = 0; // disable the generation of quasi-legal moves again
2402 if(appData.debugMode) { int n;
2403 for(n=0; n<chaseStackPointer; n++)
2404 fprintf(debugFP, "%c%c%c%c ", chaseStack[n].ff+AAA, chaseStack[n].rf+ONE,
2405 chaseStack[n].ft+AAA, chaseStack[n].rt+ONE);
2406 fprintf(debugFP, ": new capts after %c%c%c%c\n", cl.ff+AAA, cl.rf+ONE, cl.ft+AAA, cl.rt+ONE);
2408 // chaseSack now contains all captures made possible by the move
2409 for(j=0; j<chaseStackPointer; j++) { // run through chaseStack to identify true chases
2410 int attacker = (int)boards[i+1][chaseStack[j].rf][chaseStack[j].ff];
2411 int victim = (int)boards[i+1][chaseStack[j].rt][chaseStack[j].ft];
2413 if(attacker >= (int) BlackPawn) attacker = BLACK_TO_WHITE attacker; // convert to white, as piecee type
2414 if(victim >= (int) BlackPawn) victim = BLACK_TO_WHITE victim;
2416 if((attacker == WhiteKnight || attacker == WhiteCannon) && victim == WhiteRook)
2417 continue; // C or H attack on R is always chase; leave on chaseStack
2419 if(attacker == victim) {
2420 if(LegalityTest(boards[i+1], PosFlags(i+1), chaseStack[j].rt,
2421 chaseStack[j].ft, chaseStack[j].rf, chaseStack[j].ff, NULLCHAR) == NormalMove) {
2422 // we can capture back with equal piece, so this is no chase but a sacrifice
2423 chaseStack[j] = chaseStack[--chaseStackPointer]; // delete the capture from the chaseStack
2424 j--; /* ! */ continue;
2429 // the attack is on a lower piece, or on a pinned or blocked equal one
2430 CopyBoard(xqCheckers, nullBoard); xqCheckers[EP_STATUS] = 1;
2431 CheckTest(boards[i+1], PosFlags(i+1), -1, -1, -1, -1, FALSE); // if we deliver check with our move, the checkers get marked
2432 // test if the victim is protected by a true protector. First make the capture.
2433 captured = boards[i+1][chaseStack[j].rt][chaseStack[j].ft];
2434 boards[i+1][chaseStack[j].rt][chaseStack[j].ft] = boards[i+1][chaseStack[j].rf][chaseStack[j].ff];
2435 boards[i+1][chaseStack[j].rf][chaseStack[j].ff] = EmptySquare;
2436 // Then test if the opponent can recapture
2437 cl.recaptures = 0; // prepare closure to pass recapture square and count moves to it
2438 cl.rt = chaseStack[j].rt;
2439 cl.ft = chaseStack[j].ft;
2440 if(appData.debugMode) {
2441 fprintf(debugFP, "test if we can recapture %c%c\n", cl.ft+AAA, cl.rt+ONE);
2443 xqCheckers[EP_STATUS] = 2; // causes GenLegal to ignore the checks we delivered with the move, in real life evaded before we captured
2444 GenLegal(boards[i+1], PosFlags(i+1), ProtectedCallback, &cl, EmptySquare); // try all moves
2445 xqCheckers[EP_STATUS] = 0; // disable quasi-legal moves again
2446 // unmake the capture
2447 boards[i+1][chaseStack[j].rf][chaseStack[j].ff] = boards[i+1][chaseStack[j].rt][chaseStack[j].ft];
2448 boards[i+1][chaseStack[j].rt][chaseStack[j].ft] = captured;
2449 // if a recapture was found, piece is protected, and we are not chasing it.
2450 if(cl.recaptures) { // attacked piece was defended by true protector, no chase
2451 chaseStack[j] = chaseStack[--chaseStackPointer]; // so delete from chaseStack
2455 // chaseStack now contains all moves that chased
2456 if(appData.debugMode) { int n;
2457 for(n=0; n<chaseStackPointer; n++)
2458 fprintf(debugFP, "%c%c%c%c ", chaseStack[n].ff+AAA, chaseStack[n].rf+ONE,
2459 chaseStack[n].ft+AAA, chaseStack[n].rt+ONE);
2460 fprintf(debugFP, ": chases\n");
2462 if(i == first) { // copy all people chased by first move of repeat cycle to preyStack
2463 for(j=0; j<chaseStackPointer; j++) {
2464 preyStack[j].rank = chaseStack[j].rt;
2465 preyStack[j].file = chaseStack[j].ft;
2467 preyStackPointer = chaseStackPointer;
2470 for(j=0; j<chaseStackPointer; j++) {
2471 for(k=0; k<preyStackPointer; k++) {
2472 // search the victim of each chase move on the preyStack (first occurrence)
2473 if(chaseStack[j].ft == preyStack[k].file && chaseStack[j].rt == preyStack[k].rank ) {
2474 if(k < tail) break; // piece was already identified as still being chased
2475 preyStack[preyStackPointer] = preyStack[tail]; // move chased piece to bottom part of preyStack
2476 preyStack[tail] = preyStack[k]; // by swapping
2477 preyStack[k] = preyStack[preyStackPointer];
2483 preyStackPointer = tail; // keep bottom part of preyStack, popping pieces unchased on move i.
2484 if(appData.debugMode) { int n;
2485 for(n=0; n<preyStackPointer; n++)
2486 fprintf(debugFP, "%c%c ", preyStack[n].file+AAA, preyStack[n].rank+ONE);
2487 fprintf(debugFP, "always chased upto ply %d\n", i);
2489 // now adjust the location of the chased pieces according to opponent move
2490 for(j=0; j<preyStackPointer; j++) {
2491 if(preyStack[j].rank == moveList[i+1][1]-ONE &&
2492 preyStack[j].file == moveList[i+1][0]-AAA+BOARD_LEFT) {
2493 preyStack[j].rank = moveList[i+1][3]-ONE;
2494 preyStack[j].file = moveList[i+1][2]-AAA+BOARD_LEFT;
2499 return preyStackPointer ? 256*(preyStack[preyStackPointer].file - BOARD_LEFT + AAA) + (preyStack[preyStackPointer].rank + ONE)
2500 : 0; // if any piece was left on preyStack, it has been perpetually chased,and we return the