static void add_en_passant_captures(list_t * list, const board_t * board) { int from, to; int me; int inc; int pawn; ASSERT(list!=NULL); ASSERT(board!=NULL); to = board->ep_square; if (to != SquareNone) { me = board->turn; inc = PAWN_MOVE_INC(me); pawn = PAWN_MAKE(me); from = to - (inc-1); if (board->square[from] == pawn) { ASSERT(!SQUARE_IS_PROMOTE(to)); LIST_ADD(list,MOVE_MAKE_FLAGS(from,to,MoveEnPassant)); } from = to - (inc+1); if (board->square[from] == pawn) { ASSERT(!SQUARE_IS_PROMOTE(to)); LIST_ADD(list,MOVE_MAKE_FLAGS(from,to,MoveEnPassant)); } } }
static void alist_build(alist_t * alist, const board_t * board, int to, int colour) { const sq_t * ptr; int from; int piece; int delta; int inc; int sq; int pawn; ASSERT(alist!=NULL); ASSERT(board!=NULL); ASSERT(SQUARE_IS_OK(to)); ASSERT(COLOUR_IS_OK(colour)); // piece attacks for (ptr = &board->piece[colour][0]; (from=*ptr) != SquareNone; ptr++) { piece = board->square[from]; delta = to - from; if (PSEUDO_ATTACK(piece,delta)) { inc = DELTA_INC_ALL(delta); ASSERT(inc!=IncNone); sq = from; do { sq += inc; if (sq == to) { // attack alist_add(alist,from,board); break; } } while (board->square[sq] == Empty); } } // pawn attacks inc = PAWN_MOVE_INC(colour); pawn = PAWN_MAKE(colour); from = to - (inc-1); if (board->square[from] == pawn) alist_add(alist,from,board); from = to - (inc+1); if (board->square[from] == pawn) alist_add(alist,from,board); }
static bool add_pawn_moves(list_t * list, const board_t * board, int to, bool legal, bool stop) { int me; int inc; int pawn; int from; int piece; ASSERT(list!=NULL); ASSERT(board!=NULL); ASSERT(SQUARE_IS_OK(to)); ASSERT(legal==true||legal==false); ASSERT(stop==true||stop==false); ASSERT(board->square[to]==Empty); me = board->turn; inc = PAWN_MOVE_INC(me); pawn = PAWN_MAKE(me); from = to - inc; piece = board->square[from]; if (piece == pawn) { // single push if (!legal || !is_pinned(board,from,me)) { if (stop) return true; add_pawn_move(list,from,to); } } else if (piece == Empty && PAWN_RANK(to,me) == Rank4) { // double push from = to - (2*inc); if (board->square[from] == pawn) { if (!legal || !is_pinned(board,from,me)) { if (stop) return true; ASSERT(!SQUARE_IS_PROMOTE(to)); LIST_ADD(list,MOVE_MAKE(from,to)); } } } return false; }
bool is_attacked(const board_t * board, int to, int colour) { int inc; int pawn; const sq_t * ptr; int from; int piece; int delta; int sq; ASSERT(board!=NULL); ASSERT(SQUARE_IS_OK(to)); ASSERT(COLOUR_IS_OK(colour)); // pawn attack inc = PAWN_MOVE_INC(colour); pawn = PAWN_MAKE(colour); if (board->square[to-(inc-1)] == pawn) return true; if (board->square[to-(inc+1)] == pawn) return true; // piece attack for (ptr = &board->piece[colour][0]; (from=*ptr) != SquareNone; ptr++) { piece = board->square[from]; delta = to - from; if (PSEUDO_ATTACK(piece,delta)) { inc = DELTA_INC_ALL(delta); ASSERT(inc!=IncNone); sq = from; do { sq += inc; if (sq == to) return true; } while (board->square[sq] == Empty); } } return false; }
void board_from_fen(board_t * board, const char fen[]) { int pos; int file, rank, sq; int c; int i, len; int piece; int pawn; ASSERT(board!=NULL); ASSERT(fen!=NULL); board_clear(board); pos = 0; c = fen[pos]; // piece placement for (rank = Rank8; rank >= Rank1; rank--) { for (file = FileA; file <= FileH;) { if (c >= '1' && c <= '8') { // empty square(s) len = c - '0'; for (i = 0; i < len; i++) { if (file > FileH) my_fatal("board_from_fen(): bad FEN (pos=%d)\n",pos); board->square[SQUARE_MAKE(file,rank)] = Empty; file++; } } else { // piece piece = piece_from_char(c); if (piece == PieceNone256) my_fatal("board_from_fen(): bad FEN (pos=%d)\n",pos); board->square[SQUARE_MAKE(file,rank)] = piece; file++; } c = fen[++pos]; } if (rank > Rank1) { if (c != '/') my_fatal("board_from_fen(): bad FEN (pos=%d)\n",pos); c = fen[++pos]; } } // active colour if (c != ' ') my_fatal("board_from_fen(): bad FEN (pos=%d)\n",pos); c = fen[++pos]; switch (c) { case 'w': board->turn = White; break; case 'b': board->turn = Black; break; default: my_fatal("board_from_fen(): bad FEN (pos=%d)\n",pos); break; } c = fen[++pos]; // castling if (c != ' ') my_fatal("board_from_fen(): bad FEN (pos=%d)\n",pos); c = fen[++pos]; board->flags = FlagsNone; if (c == '-') { // no castling rights c = fen[++pos]; } else { if (c == 'K') { if (board->square[E1] == WK && board->square[H1] == WR) board->flags |= FlagsWhiteKingCastle; c = fen[++pos]; } if (c == 'Q') { if (board->square[E1] == WK && board->square[A1] == WR) board->flags |= FlagsWhiteQueenCastle; c = fen[++pos]; } if (c == 'k') { if (board->square[E8] == BK && board->square[H8] == BR) board->flags |= FlagsBlackKingCastle; c = fen[++pos]; } if (c == 'q') { if (board->square[E8] == BK && board->square[A8] == BR) board->flags |= FlagsBlackQueenCastle; c = fen[++pos]; } } // en-passant if (c != ' ') my_fatal("board_from_fen(): bad FEN (pos=%d)\n",pos); c = fen[++pos]; if (c == '-') { // no en-passant sq = SquareNone; c = fen[++pos]; } else { if (c < 'a' || c > 'h') my_fatal("board_from_fen(): bad FEN (pos=%d)\n",pos); file = file_from_char(c); c = fen[++pos]; if (c != (COLOUR_IS_WHITE(board->turn) ? '6' : '3')) my_fatal("board_from_fen(): bad FEN (pos=%d)\n",pos); rank = rank_from_char(c); c = fen[++pos]; sq = SQUARE_MAKE(file,rank); pawn = SQUARE_EP_DUAL(sq); if (board->square[sq] != Empty || board->square[pawn] != PAWN_MAKE(COLOUR_OPP(board->turn)) || (board->square[pawn-1] != PAWN_MAKE(board->turn) && board->square[pawn+1] != PAWN_MAKE(board->turn))) { sq = SquareNone; } } board->ep_square = sq; // halfmove clock board->ply_nb = 0; if (c != ' ') { if (!Strict) goto update; my_fatal("board_from_fen(): bad FEN (pos=%d)\n",pos); } c = fen[++pos]; if (!isdigit(c)) { if (!Strict) goto update; my_fatal("board_from_fen(): bad FEN (pos=%d)\n",pos); } board->ply_nb = atoi(&fen[pos]); // board update update: board_init_list(board); }
static bool add_pawn_captures(list_t * list, const board_t * board, int to, bool legal, bool stop) { int me; int inc; int pawn; int from; ASSERT(list!=NULL); ASSERT(board!=NULL); ASSERT(SQUARE_IS_OK(to)); ASSERT(legal==true||legal==false); ASSERT(stop==true||stop==false); ASSERT(COLOUR_IS(board->square[to],COLOUR_OPP(board->turn))); me = board->turn; inc = PAWN_MOVE_INC(me); pawn = PAWN_MAKE(me); from = to - (inc-1); if (board->square[from] == pawn) { if (!legal || !is_pinned(board,from,me)) { if (stop) return true; add_pawn_move(list,from,to); } } from = to - (inc+1); if (board->square[from] == pawn) { if (!legal || !is_pinned(board,from,me)) { if (stop) return true; add_pawn_move(list,from,to); } } if (board->ep_square != SquareNone && to == SQUARE_EP_DUAL(board->ep_square)) { ASSERT(PAWN_RANK(to,me)==Rank5); ASSERT(PIECE_IS_PAWN(board->square[to])); to = board->ep_square; ASSERT(PAWN_RANK(to,me)==Rank6); ASSERT(board->square[to]==Empty); from = to - (inc-1); if (board->square[from] == pawn) { if (!legal || !is_pinned(board,from,me)) { if (stop) return true; ASSERT(!SQUARE_IS_PROMOTE(to)); LIST_ADD(list,MOVE_MAKE_FLAGS(from,to,MoveEnPassant)); } } from = to - (inc+1); if (board->square[from] == pawn) { if (!legal || !is_pinned(board,from,me)) { if (stop) return true; ASSERT(!SQUARE_IS_PROMOTE(to)); LIST_ADD(list,MOVE_MAKE_FLAGS(from,to,MoveEnPassant)); } } } return false; }
static void add_quiet_checks(list_t * list, const board_t * board) { int me, opp; int king; const sq_t * ptr, * ptr_2; int from, to, sq; int piece; const inc_t * inc_ptr; int inc; int pawn; int rank; int pin[8+1]; ASSERT(list!=NULL); ASSERT(board!=NULL); // init me = board->turn; opp = COLOUR_OPP(me); king = KING_POS(board,opp); find_pins(pin,board); // indirect checks for (ptr = pin; (from=*ptr) != SquareNone; ptr++) { piece = board->square[from]; ASSERT(is_pinned(board,from,opp)); if (PIECE_IS_PAWN(piece)) { inc = PAWN_MOVE_INC(me); rank = PAWN_RANK(from,me); if (rank != Rank7) { // promotes are generated with captures to = from + inc; if (board->square[to] == Empty) { if (DELTA_INC_LINE(to-king) != DELTA_INC_LINE(from-king)) { ASSERT(!SQUARE_IS_PROMOTE(to)); LIST_ADD(list,MOVE_MAKE(from,to)); if (rank == Rank2) { to = from + (2*inc); if (board->square[to] == Empty) { ASSERT(DELTA_INC_LINE(to-king)!=DELTA_INC_LINE(from-king)); ASSERT(!SQUARE_IS_PROMOTE(to)); LIST_ADD(list,MOVE_MAKE(from,to)); } } } } } } else if (PIECE_IS_SLIDER(piece)) { for (inc_ptr = PIECE_INC(piece); (inc=*inc_ptr) != IncNone; inc_ptr++) { for (to = from+inc; board->square[to] == Empty; to += inc) { ASSERT(DELTA_INC_LINE(to-king)!=DELTA_INC_LINE(from-king)); LIST_ADD(list,MOVE_MAKE(from,to)); } } } else { for (inc_ptr = PIECE_INC(piece); (inc=*inc_ptr) != IncNone; inc_ptr++) { to = from + inc; if (board->square[to] == Empty) { if (DELTA_INC_LINE(to-king) != DELTA_INC_LINE(from-king)) { LIST_ADD(list,MOVE_MAKE(from,to)); } } } } } // piece direct checks for (ptr = &board->piece[me][1]; (from=*ptr) != SquareNone; ptr++) { // HACK: no king for (ptr_2 = pin; (sq=*ptr_2) != SquareNone; ptr_2++) { if (sq == from) goto next_piece; } ASSERT(!is_pinned(board,from,opp)); piece = board->square[from]; inc_ptr = PIECE_INC(piece); if (PIECE_IS_SLIDER(piece)) { for (; (inc=*inc_ptr) != IncNone; inc_ptr++) { for (to = from+inc; board->square[to] == Empty; to += inc) { if (PIECE_ATTACK(board,piece,to,king)) { LIST_ADD(list,MOVE_MAKE(from,to)); } } } } else { for (; (inc=*inc_ptr) != IncNone; inc_ptr++) { to = from + inc; if (board->square[to] == Empty) { if (PSEUDO_ATTACK(piece,king-to)) { LIST_ADD(list,MOVE_MAKE(from,to)); } } } } next_piece: ; } // pawn direct checks inc = PAWN_MOVE_INC(me); pawn = PAWN_MAKE(me); to = king - (inc-1); ASSERT(PSEUDO_ATTACK(pawn,king-to)); from = to - inc; if (board->square[from] == pawn) { if (board->square[to] == Empty) { ASSERT(!SQUARE_IS_PROMOTE(to)); LIST_ADD(list,MOVE_MAKE(from,to)); } } else { from = to - (2*inc); if (board->square[from] == pawn) { if (PAWN_RANK(from,me) == Rank2 && board->square[to] == Empty && board->square[from+inc] == Empty) { ASSERT(!SQUARE_IS_PROMOTE(to)); LIST_ADD(list,MOVE_MAKE(from,to)); } } } to = king - (inc+1); ASSERT(PSEUDO_ATTACK(pawn,king-to)); from = to - inc; if (board->square[from] == pawn) { if (board->square[to] == Empty) { ASSERT(!SQUARE_IS_PROMOTE(to)); LIST_ADD(list,MOVE_MAKE(from,to)); } } else { from = to - (2*inc); if (board->square[from] == pawn) { if (PAWN_RANK(from,me) == Rank2 && board->square[to] == Empty && board->square[from+inc] == Empty) { ASSERT(!SQUARE_IS_PROMOTE(to)); LIST_ADD(list,MOVE_MAKE(from,to)); } } } }
void move_do(board_t * board, int move, undo_t * undo) { int me, opp; int from, to; int piece, pos, capture; int old_flags, new_flags; int delta; int sq; int pawn, rook; ASSERT(board!=NULL); ASSERT(move_is_ok(move)); ASSERT(undo!=NULL); ASSERT(board_is_legal(board)); // initialise undo undo->capture = false; undo->turn = board->turn; undo->flags = board->flags; undo->ep_square = board->ep_square; undo->ply_nb = board->ply_nb; undo->cap_sq = board->cap_sq; undo->opening = board->opening; undo->endgame = board->endgame; undo->key = board->key; undo->pawn_key = board->pawn_key; undo->material_key = board->material_key; // init me = board->turn; opp = COLOUR_OPP(me); from = MOVE_FROM(move); to = MOVE_TO(move); piece = board->square[from]; ASSERT(COLOUR_IS(piece,me)); // update key stack ASSERT(board->sp<StackSize); board->stack[board->sp++] = board->key; // update turn board->turn = opp; board->key ^= RANDOM_64(RandomTurn); // update castling rights old_flags = board->flags; new_flags = old_flags & CastleMask[from] & CastleMask[to]; board->flags = new_flags; board->key ^= Castle64[new_flags^old_flags]; // HACK // update en-passant square if ((sq=board->ep_square) != SquareNone) { board->key ^= RANDOM_64(RandomEnPassant+SQUARE_FILE(sq)-FileA); board->ep_square = SquareNone; } if (PIECE_IS_PAWN(piece)) { delta = to - from; if (delta == +32 || delta == -32) { pawn = PAWN_MAKE(opp); if (board->square[to-1] == pawn || board->square[to+1] == pawn) { board->ep_square = (from + to) / 2; board->key ^= RANDOM_64(RandomEnPassant+SQUARE_FILE(to)-FileA); } } } // update move number (captures are handled later) board->ply_nb++; if (PIECE_IS_PAWN(piece)) board->ply_nb = 0; // conversion // update last square board->cap_sq = SquareNone; // remove the captured piece sq = to; if (MOVE_IS_EN_PASSANT(move)) sq = SQUARE_EP_DUAL(sq); if ((capture=board->square[sq]) != Empty) { ASSERT(COLOUR_IS(capture,opp)); ASSERT(!PIECE_IS_KING(capture)); undo->capture = true; undo->capture_square = sq; undo->capture_piece = capture; undo->capture_pos = board->pos[sq]; square_clear(board,sq,capture,true); board->ply_nb = 0; // conversion board->cap_sq = to; } // move the piece if (MOVE_IS_PROMOTE(move)) { // promote undo->pawn_pos = board->pos[from]; square_clear(board,from,piece,true); piece = move_promote(move); // insert the promote piece in MV order for (pos = board->piece_size[me]; pos > 0 && piece > board->square[board->piece[me][pos-1]]; pos--) // HACK ; square_set(board,to,piece,pos,true); board->cap_sq = to; } else { // normal move square_move(board,from,to,piece,true); } // move the rook in case of castling if (MOVE_IS_CASTLE(move)) { rook = Rook64 | COLOUR_FLAG(me); // HACK if (to == G1) { square_move(board,H1,F1,rook,true); } else if (to == C1) { square_move(board,A1,D1,rook,true); } else if (to == G8) { square_move(board,H8,F8,rook,true); } else if (to == C8) { square_move(board,A8,D8,rook,true); } else { ASSERT(false); } } // debug ASSERT(board_is_ok(board)); }
void move_undo(board_t * board, int move, const undo_t * undo) { int me; int from, to; int piece, pos; int rook; ASSERT(board!=NULL); ASSERT(move_is_ok(move)); ASSERT(undo!=NULL); // init me = undo->turn; from = MOVE_FROM(move); to = MOVE_TO(move); piece = board->square[to]; ASSERT(COLOUR_IS(piece,me)); // castle if (MOVE_IS_CASTLE(move)) { rook = Rook64 | COLOUR_FLAG(me); // HACK if (to == G1) { square_move(board,F1,H1,rook,false); } else if (to == C1) { square_move(board,D1,A1,rook,false); } else if (to == G8) { square_move(board,F8,H8,rook,false); } else if (to == C8) { square_move(board,D8,A8,rook,false); } else { ASSERT(false); } } // move the piece backward if (MOVE_IS_PROMOTE(move)) { // promote ASSERT(piece==move_promote(move)); square_clear(board,to,piece,false); piece = PAWN_MAKE(me); pos = undo->pawn_pos; square_set(board,from,piece,pos,false); } else { // normal move square_move(board,to,from,piece,false); } // put the captured piece back if (undo->capture) { square_set(board,undo->capture_square,undo->capture_piece,undo->capture_pos,false); } // update board info board->turn = undo->turn; board->flags = undo->flags; board->ep_square = undo->ep_square; board->ply_nb = undo->ply_nb; board->cap_sq = undo->cap_sq; board->opening = undo->opening; board->endgame = undo->endgame; board->key = undo->key; board->pawn_key = undo->pawn_key; board->material_key = undo->material_key; // update key stack ASSERT(board->sp>0); board->sp--; // debug ASSERT(board_is_ok(board)); ASSERT(board_is_legal(board)); }
void attack_set(attack_t * attack, const board_t * board) { int me, opp; const sq_t * ptr; int from, to; int inc; int pawn; int delta, piece; int sq; ASSERT(attack!=NULL); ASSERT(board!=NULL); // init attack->dn = 0; me = board->turn; opp = COLOUR_OPP(me); to = KING_POS(board,me); // pawn attacks inc = PAWN_MOVE_INC(opp); pawn = PAWN_MAKE(opp); from = to - (inc-1); if (board->square[from] == pawn) { attack->ds[attack->dn] = from; attack->di[attack->dn] = IncNone; attack->dn++; } from = to - (inc+1); if (board->square[from] == pawn) { attack->ds[attack->dn] = from; attack->di[attack->dn] = IncNone; attack->dn++; } // piece attacks for (ptr = &board->piece[opp][1]; (from=*ptr) != SquareNone; ptr++) { // HACK: no king piece = board->square[from]; delta = to - from; ASSERT(delta_is_ok(delta)); if (PSEUDO_ATTACK(piece,delta)) { inc = IncNone; if (PIECE_IS_SLIDER(piece)) { // check for blockers inc = DELTA_INC_LINE(delta); ASSERT(inc!=IncNone); sq = from; do sq += inc; while (board->square[sq] == Empty); if (sq != to) continue; // blocker => next attacker } attack->ds[attack->dn] = from; attack->di[attack->dn] = -inc; // HACK attack->dn++; } } attack->ds[attack->dn] = SquareNone; attack->di[attack->dn] = IncNone; // debug ASSERT(attack_is_ok(attack)); }