Bitboard SEE::extractShadowAttacker(const Position& position,
Bitboard bb,
Square from,
Square to) {
Direction dir = from.dir(to);
if (dir >= Direction::EndS) {
return bb;
}
Bitboard occ = nosseOr(position.getBOccupiedBitboard(),
position.getWOccupiedBitboard());
RotatedBitboard occ90 = position.get90RotatedBitboard();
RotatedBitboard occR45 = position.getRight45RotatedBitboard();
RotatedBitboard occL45 = position.getLeft45RotatedBitboard();
Bitboard masked;
switch (dir) {
case Direction::Up:
case Direction::Down:
masked = MoveTables::ver(occ, from);
break;
case Direction::Left:
case Direction::Right:
masked = MoveTables::hor(occ90, from);
break;
case Direction::RightUp:
case Direction::LeftDown:
masked = MoveTables::diagR45(occR45, to);
break;
case Direction::LeftUp:
case Direction::RightDown:
masked = MoveTables::diagL45(occL45, to);
break;
default:
ASSERT(false);
}
BB_EACH(square, masked) {
Piece piece = position.getPieceOnBoard(square);
if (square.dir(from) == dir && MoveTables::isMovableInLongStep(piece, dir)) {
bb.set(square);
break;
}
}
MoveStack* generateDropMoves20151211(MoveStack* moveStackList, const Position& pos, const Bitboard& target) {
const Hand hand = pos.hand(US);
// まず、歩に対して指し手を生成
if (hand.exists<HPawn>()) {
Bitboard toBB = target;
// 一段目には打てない
const Rank TRank9 = (US == Black ? Rank9 : Rank1);
toBB.andEqualNot(rankMask<TRank9>());
// 二歩の回避
Bitboard pawnsBB = pos.bbOf(Pawn, US);
Square pawnsSquare;
foreachBB(pawnsBB, pawnsSquare, [&](const int part) {
toBB.set(part, toBB.p(part) & ~squareFileMask(pawnsSquare).p(part));
});
// 打ち歩詰めの回避
const Rank TRank1 = (US == Black ? Rank1 : Rank9);
const SquareDelta TDeltaS = (US == Black ? DeltaS : DeltaN);
const Square ksq = pos.kingSquare(oppositeColor(US));
// 相手玉が九段目なら、歩で王手出来ないので、打ち歩詰めを調べる必要はない。
if (makeRank(ksq) != TRank1) {
const Square pawnDropCheckSquare = ksq + TDeltaS;
assert(isInSquare(pawnDropCheckSquare));
if (toBB.isSet(pawnDropCheckSquare) && pos.piece(pawnDropCheckSquare) == Empty) {
if (!pos.isPawnDropCheckMate(US, pawnDropCheckSquare)) {
// ここで clearBit だけして MakeMove しないことも出来る。
// 指し手が生成される順番が変わり、王手が先に生成されるが、後で問題にならないか?
(*moveStackList++).move = makeDropMove(Pawn, pawnDropCheckSquare);
}
toBB.xorBit(pawnDropCheckSquare);
}
}
Square to;
FOREACH_BB(toBB, to, {
(*moveStackList++).move = makeDropMove(Pawn, to);
});