// Generate evasions for king
Bitboard b1 = pos.piece_attacks_from<KING>(ksq) & ~pos.pieces_of_color(us) & ~checkersAttacks;
+ Bitboard enemy = pos.pieces_of_color(them);
while (b1)
{
to = pop_1st_bit(&b1);
// Note that we can use attackers_to() only because we
// have already removed slider checkers.
- if (!pos.attackers_to(to, them))
+ if (!(pos.attackers_to(to) & enemy))
(*mlist++).move = make_move(ksq, to);
}
// is occupied or under attack.
for (s = Min(from, g1); s <= Max(from, g1); s++)
if ( (s != from && s != to && !pos.square_is_empty(s))
- || pos.attackers_to(s, them))
+ ||(pos.attackers_to(s) & pos.pieces_of_color(them)))
illegal = true;
// Check if any of the squares between king and rook
for (s = Min(from, c1); s <= Max(from, c1); s++)
if( (s != from && s != to && !pos.square_is_empty(s))
- || pos.attackers_to(s, them))
+ ||(pos.attackers_to(s) & pos.pieces_of_color(them)))
illegal = true;
for (s = Min(to, d1); s <= Max(to, d1); s++)
// It is a bit complicated to correctly handle Chess960
for (s = Min(ksq, s1); s <= Max(ksq, s1); s++)
if ( (s != ksq && s != rsq && pos.square_is_occupied(s))
- || pos.attackers_to(s, them))
+ ||(pos.attackers_to(s) & pos.pieces_of_color(them)))
illegal = true;
for (s = Min(rsq, s2); s <= Max(rsq, s2); s++)
void Position::find_checkers() {
Color us = side_to_move();
- st->checkersBB = attackers_to(king_square(us), opposite_color(us));
+ st->checkersBB = attackers_to(king_square(us)) & pieces_of_color(opposite_color(us));
}
// If the moving piece is a king, check whether the destination
// square is attacked by the opponent.
if (type_of_piece_on(from) == KING)
- return !attackers_to(move_to(m), opposite_color(us));
+ return !(attackers_to(move_to(m)) & pieces_of_color(opposite_color(us)));
// A non-king move is legal if and only if it is not pinned or it
// is moving along the ray towards or away from the king.
// Update checkers bitboard, piece must be already moved
if (ep | pm)
- st->checkersBB = attackers_to(king_square(them), us);
+ st->checkersBB = attackers_to(king_square(them)) & pieces_of_color(us);
else
{
st->checkersBB = EmptyBoardBB;
st->rule50 = 0;
// Update checkers BB
- st->checkersBB = attackers_to(king_square(them), us);
+ st->checkersBB = attackers_to(king_square(them)) & pieces_of_color(us);
// Finish
sideToMove = opposite_color(sideToMove);
while (true)
{
clear_bit(&occ, from);
- attackers = (rook_attacks_bb(to, occ) & pieces(ROOK, QUEEN))
- | (bishop_attacks_bb(to, occ) & pieces(BISHOP, QUEEN))
- | (piece_attacks_from<KNIGHT>(to) & pieces(KNIGHT))
- | (piece_attacks_from<KING>(to) & pieces(KING))
- | (pawn_attacks_from(to, WHITE) & pieces(PAWN, BLACK))
- | (pawn_attacks_from(to, BLACK) & pieces(PAWN, WHITE));
+ attackers = (rook_attacks_bb(to, occ) & pieces(ROOK, QUEEN))
+ | (bishop_attacks_bb(to, occ) & pieces(BISHOP, QUEEN))
+ | (piece_attacks_from<KNIGHT>(to) & pieces(KNIGHT))
+ | (piece_attacks_from<KING>(to) & pieces(KING))
+ | (pawn_attacks_from(to, WHITE) & pieces(PAWN, BLACK))
+ | (pawn_attacks_from(to, BLACK) & pieces(PAWN, WHITE));
if (from != SQ_NONE)
break;
Color us = side_to_move();
Color them = opposite_color(us);
Square ksq = king_square(them);
- if (attackers_to(ksq, us))
+ if (attackers_to(ksq) & pieces_of_color(us))
return false;
}
// Information about attacks to or from a given square
Bitboard attackers_to(Square s) const;
- Bitboard attackers_to(Square s, Color c) const;
Bitboard piece_attacks_from(Piece p, Square s) const;
Bitboard pawn_attacks_from(Square s, Color c) const;
template<PieceType> Bitboard piece_attacks_from(Square s) const;
return st->checkersBB != EmptyBoardBB;
}
-inline Bitboard Position::attackers_to(Square s, Color c) const {
-
- return attackers_to(s) & pieces_of_color(c);
-}
-
inline bool Position::pawn_is_passed(Color c, Square s) const {
return !(pieces(PAWN, opposite_color(c)) & passed_pawn_mask(c, s));
}