- sideToMove = opposite_color(sideToMove);
- st->value += (sideToMove == WHITE ? TempoValue : -TempoValue);
-
- assert(is_ok());
-}
-
-
-/// Position::do_capture_move() is a private method used to update captured
-/// piece info. It is called from the main Position::do_move function.
-
-void Position::do_capture_move(Key& key, PieceType capture, Color them, Square to, bool ep) {
-
- assert(capture != KING);
-
- Square capsq = to;
-
- // If the captured piece was a pawn, update pawn hash key,
- // otherwise update non-pawn material.
- if (capture == PAWN)
- {
- if (ep) // en passant ?
- {
- capsq = to + pawn_push(them);
-
- assert(to == st->epSquare);
- assert(relative_rank(opposite_color(them), to) == RANK_6);
- assert(piece_on(to) == PIECE_NONE);
- assert(piece_on(capsq) == make_piece(them, PAWN));
-
- board[capsq] = PIECE_NONE;
- }
- st->pawnKey ^= zobrist[them][PAWN][capsq];
- }
- else
- st->npMaterial[them] -= PieceValueMidgame[capture];
-
- // Remove captured piece
- clear_bit(&byColorBB[them], capsq);
- clear_bit(&byTypeBB[capture], capsq);
- clear_bit(&byTypeBB[0], capsq);
-
- // Update hash key
- key ^= zobrist[them][capture][capsq];
-
- // Update incremental scores
- st->value -= pst(make_piece(them, capture), capsq);
-
- // Update piece count
- pieceCount[them][capture]--;
-
- // Update material hash key
- st->materialKey ^= zobrist[them][capture][pieceCount[them][capture]];
-
- // Update piece list, move the last piece at index[capsq] position
- //
- // WARNING: This is a not perfectly revresible operation. When we
- // will reinsert the captured piece in undo_move() we will put it
- // at the end of the list and not in its original place, it means
- // index[] and pieceList[] are not guaranteed to be invariant to a
- // do_move() + undo_move() sequence.
- Square lastPieceSquare = pieceList[them][capture][pieceCount[them][capture]];
- index[lastPieceSquare] = index[capsq];
- pieceList[them][capture][index[lastPieceSquare]] = lastPieceSquare;
- pieceList[them][capture][pieceCount[them][capture]] = SQ_NONE;
-
- // Reset rule 50 counter
- st->rule50 = 0;
-}
-
-
-/// Position::do_castle_move() is a private method used to make a castling
-/// move. It is called from the main Position::do_move function. Note that
-/// castling moves are encoded as "king captures friendly rook" moves, for
-/// instance white short castling in a non-Chess960 game is encoded as e1h1.
-
-void Position::do_castle_move(Move m) {
-
- assert(move_is_ok(m));
- assert(move_is_castle(m));
-
- Color us = side_to_move();
- Color them = opposite_color(us);
-
- // Find source squares for king and rook
- Square kfrom = move_from(m);
- Square rfrom = move_to(m);
- Square kto, rto;
-
- assert(piece_on(kfrom) == make_piece(us, KING));
- assert(piece_on(rfrom) == make_piece(us, ROOK));
-
- // Find destination squares for king and rook
- if (rfrom > kfrom) // O-O
- {
- kto = relative_square(us, SQ_G1);
- rto = relative_square(us, SQ_F1);
- }
- else // O-O-O
- {
- kto = relative_square(us, SQ_C1);
- rto = relative_square(us, SQ_D1);
- }
-
- // Remove pieces from source squares
- clear_bit(&byColorBB[us], kfrom);
- clear_bit(&byTypeBB[KING], kfrom);
- clear_bit(&byTypeBB[0], kfrom);
- clear_bit(&byColorBB[us], rfrom);
- clear_bit(&byTypeBB[ROOK], rfrom);
- clear_bit(&byTypeBB[0], rfrom);
-
- // Put pieces on destination squares
- set_bit(&byColorBB[us], kto);
- set_bit(&byTypeBB[KING], kto);
- set_bit(&byTypeBB[0], kto);
- set_bit(&byColorBB[us], rto);
- set_bit(&byTypeBB[ROOK], rto);
- set_bit(&byTypeBB[0], rto);
-
- // Update board
- Piece king = make_piece(us, KING);
- Piece rook = make_piece(us, ROOK);
- board[kfrom] = board[rfrom] = PIECE_NONE;
- board[kto] = king;
- board[rto] = rook;
-
- // Update piece lists
- pieceList[us][KING][index[kfrom]] = kto;
- pieceList[us][ROOK][index[rfrom]] = rto;
- int tmp = index[rfrom]; // In Chess960 could be kto == rfrom
- index[kto] = index[kfrom];
- index[rto] = tmp;
-
- // Reset capture field
- st->capturedType = PIECE_TYPE_NONE;
-
- // Update incremental scores
- st->value += pst_delta(king, kfrom, kto);
- st->value += pst_delta(rook, rfrom, rto);
-
- // Update hash key
- st->key ^= zobrist[us][KING][kfrom] ^ zobrist[us][KING][kto];
- st->key ^= zobrist[us][ROOK][rfrom] ^ zobrist[us][ROOK][rto];
-
- // Clear en passant square
- if (st->epSquare != SQ_NONE)
- {
- st->key ^= zobEp[st->epSquare];
- st->epSquare = SQ_NONE;
- }
-
- // Update castling rights
- st->key ^= zobCastle[st->castleRights];
- st->castleRights &= castleRightsMask[kfrom];
- st->key ^= zobCastle[st->castleRights];
-
- // Reset rule 50 counter
- st->rule50 = 0;
-
- // Update checkers BB
- st->checkersBB = attackers_to(king_square(them)) & pieces(us);
-
- // Finish
- sideToMove = opposite_color(sideToMove);