if (attackers_to(s) & pieces(~us))
return false;
- // In case of Chess960, verify that when moving the castling rook we do
- // not discover some hidden checker.
+ // In case of Chess960, verify if the Rook blocks some checks
// For instance an enemy queen in SQ_A1 when castling rook is in SQ_B1.
- return !chess960
- || !(attacks_bb<ROOK>(to, pieces() ^ to_sq(m)) & pieces(~us, ROOK, QUEEN));
+ return !chess960 || !(blockers_for_king(us) & to_sq(m));
}
// If the moving piece is a king, check whether the destination square is
Piece pc = moved_piece(m);
// Use a slower but simpler function for uncommon cases
+ // yet we skip the legality check of MoveList<LEGAL>().
if (type_of(m) != NORMAL)
- return MoveList<LEGAL>(*this).contains(m);
+ return checkers() ? MoveList< EVASIONS>(*this).contains(m)
+ : MoveList<NON_EVASIONS>(*this).contains(m);
// Is not a promotion, so promotion piece must be empty
if (promotion_type(m) - KNIGHT != NO_PIECE_TYPE)
return (attacks_bb< ROOK>(square<KING>(~sideToMove), b) & pieces(sideToMove, QUEEN, ROOK))
| (attacks_bb<BISHOP>(square<KING>(~sideToMove), b) & pieces(sideToMove, QUEEN, BISHOP));
}
- case CASTLING:
+ default: //CASTLING
{
- Square kfrom = from;
- Square rfrom = to; // Castling is encoded as 'king captures the rook'
- Square kto = relative_square(sideToMove, rfrom > kfrom ? SQ_G1 : SQ_C1);
- Square rto = relative_square(sideToMove, rfrom > kfrom ? SQ_F1 : SQ_D1);
+ // Castling is encoded as 'king captures the rook'
+ Square ksq = square<KING>(~sideToMove);
+ Square rto = relative_square(sideToMove, to > from ? SQ_F1 : SQ_D1);
- return (attacks_bb<ROOK>(rto) & square<KING>(~sideToMove))
- && (attacks_bb<ROOK>(rto, (pieces() ^ kfrom ^ rfrom) | rto | kto) & square<KING>(~sideToMove));
+ return (attacks_bb<ROOK>(rto) & ksq)
+ && (attacks_bb<ROOK>(rto, pieces() ^ from ^ to) & ksq);
}
- default:
- assert(false);
- return false;
}
}
assert(is_ok(m));
- // Only deal with normal moves, assume others pass a simple see
+ // Only deal with normal moves, assume others pass a simple SEE
if (type_of(m) != NORMAL)
return VALUE_ZERO >= threshold;