(*mlist++).move = make_move(to - (d), to); }
namespace {
- enum CastlingSide { KING_SIDE, QUEEN_SIDE };
-
template<CastlingSide Side, bool OnlyChecks>
MoveStack* generate_castle(const Position& pos, MoveStack* mlist, Color us) {
- const CastleRight CR[] = { Side ? WHITE_OOO : WHITE_OO,
- Side ? BLACK_OOO : BLACK_OO };
-
- if (!pos.can_castle(CR[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(CR[us]);
+ Square rfrom = pos.castle_rook_square(us, Side);
Square kto = relative_square(us, Side == KING_SIDE ? SQ_G1 : SQ_C1);
- Square rto = relative_square(us, Side == KING_SIDE ? SQ_F1 : SQ_D1);
Bitboard enemies = pos.pieces(~us);
assert(!pos.in_check());
- assert(pos.piece_on(kfrom) == make_piece(us, KING));
- assert(pos.piece_on(rfrom) == make_piece(us, ROOK));
-
- // Unimpeded rule: All the squares between the king's initial and final squares
- // (including the final square), and all the squares between the rook's initial
- // and final squares (including the final square), must be vacant except for
- // the king and castling rook.
- for (Square s = std::min(rfrom, rto), e = std::max(rfrom, rto); s <= e; s++)
- if (s != kfrom && s != rfrom && !pos.square_is_empty(s))
- return mlist;
for (Square s = std::min(kfrom, kto), e = std::max(kfrom, kto); s <= e; s++)
- if ( (s != kfrom && s != rfrom && !pos.square_is_empty(s))
- ||(pos.attackers_to(s) & enemies))
+ 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.occupied_squares() ^ rfrom) & enemies))
+ && (pos.attackers_to(kto, pos.pieces() ^ rfrom) & enemies))
return mlist;
(*mlist++).move = make_castle(kfrom, rfrom);
// Single and double pawn pushes, no promotions
if (Type != MV_CAPTURE)
{
- emptySquares = (Type == MV_QUIET ? target : ~pos.occupied_squares());
+ emptySquares = (Type == MV_QUIET ? target : ~pos.pieces());
b1 = move_pawns<UP>(pawnsNotOn7) & emptySquares;
b2 = move_pawns<UP>(b1 & TRank3BB) & emptySquares;
if (pawnsOn7 && (Type != MV_EVASION || (target & TRank8BB)))
{
if (Type == MV_CAPTURE)
- emptySquares = ~pos.occupied_squares();
+ emptySquares = ~pos.pieces();
if (Type == MV_EVASION)
emptySquares &= target;
if (*pl != SQ_NONE)
{
- target = ci.checkSq[Pt] & ~pos.occupied_squares(); // Non capture checks only
+ target = ci.checkSq[Pt] & ~pos.pieces(); // Non capture checks only
do {
from = *pl;
target = pos.pieces(~us);
else if (Type == MV_QUIET)
- target = ~pos.occupied_squares();
+ target = ~pos.pieces();
else if (Type == MV_NON_EVASION)
- target = pos.pieces(~us) | ~pos.occupied_squares();
+ target = ~pos.pieces(us);
mlist = (us == WHITE ? generate_pawn_moves<WHITE, Type>(pos, mlist, target)
: generate_pawn_moves<BLACK, Type>(pos, mlist, target));
if (pt == PAWN)
continue; // Will be generated togheter with direct checks
- Bitboard b = pos.attacks_from(Piece(pt), from) & ~pos.occupied_squares();
+ Bitboard b = pos.attacks_from(Piece(pt), from) & ~pos.pieces();
if (pt == KING)
b &= ~PseudoAttacks[QUEEN][ci.ksq];