-
- // Is there a mate threat?
- if (QueenContactMates && !pos.is_check())
- {
- escapeSquares = pos.attacks_from<KING>(ksq) & ~pos.pieces_of_color(Us) & ~attackedByOthers;
- occ = pos.occupied_squares();
- while (b)
- {
- to = pop_1st_bit(&b);
-
- // Do we have escape squares from queen contact check attack ?
- if (!(escapeSquares & ~queen_attacks_bb(to, occ & ClearMaskBB[ksq])))
- {
- // We have a mate, unless the queen is pinned or there
- // is an X-ray attack through the queen.
- for (int i = 0; i < pos.piece_count(Them, QUEEN); i++)
- {
- from = pos.piece_list(Them, QUEEN, i);
- if ( bit_is_set(pos.attacks_from<QUEEN>(from), to)
- && !bit_is_set(pos.pinned_pieces(Them), from)
- && !(rook_attacks_bb(to, occ & ClearMaskBB[from]) & pos.pieces(ROOK, QUEEN, Us))
- && !(bishop_attacks_bb(to, occ & ClearMaskBB[from]) & pos.pieces(BISHOP, QUEEN, Us)))
-
- // Set the mate threat move
- ei.mateThreat[Them] = make_move(from, to);
- }
- }
- }
- }
- }