FORCE_INLINE MoveStack* generateBishopOrRookMoves(MoveStack* moveStackList, const Position& pos,
const Bitboard& target, const Square /*ksq*/)
{
Bitboard fromBB = pos.bbOf(PT, US);
while (fromBB.isNot0()) {
const Square from = fromBB.firstOneFromI9();
const bool fromCanPromote = canPromote(US, makeRank(from));
Bitboard toBB = pos.attacksFrom<PT>(US, from) & target;
while (toBB.isNot0()) {
const Square to = toBB.firstOneFromI9();
const bool toCanPromote = canPromote(US, makeRank(to));
if (fromCanPromote | toCanPromote) {
(*moveStackList++).move = makePromoteMove<MT>(PT, from, to, pos);
if (MT == NonEvasion || ALL)
(*moveStackList++).move = makeNonPromoteMove<MT>(PT, from, to, pos);
}
else // 角、飛車は成れるなら成り、不成は生成しない。
(*moveStackList++).move = makeNonPromoteMove<MT>(PT, from, to, pos);
}
}
return moveStackList;
}
void BOARD::helpFindBestMoves
(
int lookAhead,
PIECECOLOR moveColor,
BOARDMETRIC &metric,
BESTMOVES *bestMoves
)
{
POSITION where;
POSITIONLIST moves;
BOARDMETRIC testMetric;
BOOL metricSet = FALSE;
MOVEUNDODATA undoData;
int m, compareResult;
int origMaterialDiff = metric.materialDiff;
MOVETYPE castleType;
testMetric.kingSituation[WHITE] = KINGOK;
testMetric.kingSituation[BLACK] = KINGOK;
// try all possible moves for the given color
for (where.row = 0; where.row < NUMROWS; where.row++)
for (where.col = 0; where.col < NUMCOLS; where.col++)
{
if (whatPiece(where))
if (whatPiece(where)->whatColor() == moveColor)
{
whatPiece(where)->legalMoves(where, *this, moves);
for (m = 0; m < moves.nMoves; m++)
{
testMetric.materialDiff = origMaterialDiff;
doMove
(
where,
moves.end[m],
undoData
);
if (undoData.capturedPiece)
{
if (undoData.capturedPiece->whatType() == TYPEKING)
{
undoMove
(
moves.end[m],
where,
undoData
);
metric.kingSituation[OtherColor(moveColor)] =
KINGLOST;
if (bestMoves)
{
bestMoves->nMoves = 0;
bestMoves->move[0] =
PIECEMOVE
(
NORMALMOVE,
where,
moves.end[m]
);
}
return;
}
testMetric.materialDiff -=
undoData.capturedPiece->signedValue();
}
if (canPromote(moves.end[m]))
{
testMetric.materialDiff -=
whatPiece(moves.end[m])->signedValue();
promote(moves.end[m], TYPEQUEEN);
testMetric.materialDiff +=
whatPiece(moves.end[m])->signedValue();
if (lookAhead > 1)
helpFindBestMoves
(
lookAhead - 1,
OtherColor(moveColor),
testMetric,
(BESTMOVES *) 0
);
compareResult = compareMetric
(
testMetric,
metric,
metricSet,
moveColor
);
if (compareResult >= 0)
{
if (compareResult > 0)
{
metric = testMetric;
metricSet = TRUE;
if (bestMoves)
bestMoves->nMoves = 0;
}
if (bestMoves)
bestMoves->move[bestMoves->nMoves++] =
PIECEMOVE
(
NORMALMOVE,
where,
moves.end[m],
TYPEQUEEN
);
}
testMetric.materialDiff -=
whatPiece(moves.end[m])->signedValue();
restorePawn(moves.end[m]);
promote(moves.end[m], TYPEKNIGHT);
testMetric.materialDiff +=
whatPiece(moves.end[m])->signedValue();
if (lookAhead > 1)
helpFindBestMoves
(
lookAhead - 1,
OtherColor(moveColor),
testMetric,
(BESTMOVES *) 0
);
compareResult = compareMetric
(
testMetric,
metric,
metricSet,
moveColor
);
if (compareResult >= 0)
{
if (compareResult > 0)
{
metric = testMetric;
metricSet = TRUE;
if (bestMoves)
bestMoves->nMoves = 0;
}
if (bestMoves)
bestMoves->move[bestMoves->nMoves++] =
PIECEMOVE
(
NORMALMOVE,
where,
moves.end[m],
TYPEKNIGHT
);
}
restorePawn(moves.end[m]);
}
else // no promotion
{
if (lookAhead > 1)
helpFindBestMoves
(
lookAhead - 1,
OtherColor(moveColor),
testMetric,
(BESTMOVES *) 0
);
compareResult = compareMetric
(
testMetric,
metric,
metricSet,
moveColor
);
if (compareResult >= 0)
{
if (compareResult > 0)
{
metric = testMetric;
metricSet = TRUE;
if (bestMoves)
bestMoves->nMoves = 0;
}
if (bestMoves)
bestMoves->move[bestMoves->nMoves++] =
PIECEMOVE
(
NORMALMOVE,
where,
moves.end[m]
);
}
}
undoMove
(
moves.end[m],
where,
undoData
);
} // end of for loop over each legal move for piece
}
} // end of double for loop over each board position
// only try castling moves if look ahead move than one, since
// nothing can be captured by doing a castling move
if (lookAhead > 1)
{
castleType = QUEENSIDECASTLE;
for ( ; ; )
{
if (canCastle(castleType, moveColor))
{
testMetric.materialDiff = origMaterialDiff;
castle(castleType, moveColor, undoData);
helpFindBestMoves
(
lookAhead - 1,
OtherColor(moveColor),
testMetric,
(BESTMOVES *) 0
);
compareResult = compareMetric
(
testMetric,
metric,
metricSet,
moveColor
);
if (compareResult >= 0)
{
if (compareResult > 0)
{
metric = testMetric;
metricSet = TRUE;
if (bestMoves)
bestMoves->nMoves = 0;
}
if (bestMoves)
bestMoves->move[bestMoves->nMoves++] =
PIECEMOVE(castleType);
}
undoCastle(castleType, moveColor, undoData);
}
if (castleType == KINGSIDECASTLE)
break;
castleType = KINGSIDECASTLE;
}
// see if the loss of the king is the result of a stalemate
// instead of check mate
if (metric.kingSituation[moveColor] == KINGLOST)
{
helpFindBestMoves
(
1,
OtherColor(moveColor),
testMetric,
(BESTMOVES *) 0
);
if (testMetric.kingSituation[moveColor] != KINGLOST)
// king will be lost on next move, but is not in check
metric.kingSituation[moveColor] = STALEMATE;
}
}
return;
}
