- template<CastlingSide Side, bool OnlyChecks>
- MoveStack* generate_castle(const Position& pos, MoveStack* mlist, Color us) {
-
- if (pos.castle_impeded(us, Side) || !pos.can_castle(make_castle_right(us, Side)))
- return mlist;
-
- // After castling, the rook and king final positions are the same in Chess960
- // as they would be in standard chess.
- Square kfrom = pos.king_square(us);
- Square rfrom = pos.castle_rook_square(us, Side);
- Square kto = relative_square(us, Side == KING_SIDE ? SQ_G1 : SQ_C1);
- Bitboard enemies = pos.pieces(~us);
-
- assert(!pos.in_check());
-
- for (Square s = std::min(kfrom, kto), e = std::max(kfrom, kto); s <= e; s++)
- if ( s != kfrom // We are not in check
- && (pos.attackers_to(s) & enemies))
- return mlist;
-
- // Because we generate only legal castling moves we need to verify that
- // when moving the castling rook we do not discover some hidden checker.
- // For instance an enemy queen in SQ_A1 when castling rook is in SQ_B1.
- if ( pos.is_chess960()
- && (pos.attackers_to(kto, pos.pieces() ^ rfrom) & enemies))
- return mlist;
-
- (*mlist++).move = make_castle(kfrom, rfrom);
-
- if (OnlyChecks && !pos.move_gives_check((mlist - 1)->move, CheckInfo(pos)))
- mlist--;
-
- return mlist;
- }