private static int GetSmallestAttackSeeMove(long[] pieces, int colorToMove, int toIndex,
long allPieces, long slidingMask)
{
// TODO stop when bad-capture
// put 'super-piece' in see position
// pawn non-promotion attacks
var attackMove = StaticMoves.PawnAttacks[1 - colorToMove][toIndex] & pieces[Pawn] & allPieces;
if (attackMove != 0)
{
return(BitOperations.TrailingZeroCount(attackMove));
}
// knight attacks
attackMove = pieces[Knight] & StaticMoves.KnightMoves[toIndex] & allPieces;
if (attackMove != 0)
{
return(BitOperations.TrailingZeroCount(attackMove));
}
// bishop attacks
if ((pieces[Bishop] & slidingMask) != 0)
{
attackMove = pieces[Bishop] & MagicUtil.GetBishopMoves(toIndex, allPieces) & allPieces;
if (attackMove != 0)
{
return(BitOperations.TrailingZeroCount(attackMove));
}
}
// rook attacks
if ((pieces[Rook] & slidingMask) != 0)
{
attackMove = pieces[Rook] & MagicUtil.GetRookMoves(toIndex, allPieces) & allPieces;
if (attackMove != 0)
{
return(BitOperations.TrailingZeroCount(attackMove));
}
}
// queen attacks
if ((pieces[Queen] & slidingMask) != 0)
{
attackMove = pieces[Queen] & MagicUtil.GetQueenMoves(toIndex, allPieces) & allPieces;
if (attackMove != 0)
{
return(BitOperations.TrailingZeroCount(attackMove));
}
}
// king attacks
attackMove = pieces[King] & StaticMoves.KingMoves[toIndex];
if (attackMove != 0)
{
return(BitOperations.TrailingZeroCount(attackMove));
}
return(-1);
}
public static int CalculateMobilityScoresAndSetAttacks(ChessBoard cb)
{
cb.ClearEvalAttacks();
for (var color = White; color <= Black; color++)
{
var kingArea = KingArea[cb.KingIndex[1 - color]];
var piece = cb.Pieces[color][Pawn] & ~cb.PinnedPieces;
while (piece != 0)
{
cb.UpdatePawnAttacks(StaticMoves.PawnAttacks[color][BitOperations.TrailingZeroCount(piece)], color);
piece &= piece - 1;
}
cb.UpdatePawnAttacks(color, kingArea);
piece = cb.Pieces[color][Pawn] & cb.PinnedPieces;
while (piece != 0)
{
cb.UpdateAttacks(StaticMoves.PawnAttacks[color][BitOperations.TrailingZeroCount(piece)]
& PinnedMovement[BitOperations.TrailingZeroCount(piece)][cb.KingIndex[color]],
Pawn,
color, kingArea);
piece &= piece - 1;
}
}
var score = 0;
long moves;
for (var color = White; color <= Black; color++)
{
var tempScore = 0;
var kingArea = KingArea[cb.KingIndex[1 - color]];
var safeMoves = ~cb.Pieces[color][All] & ~cb.Attacks[1 - color][Pawn];
// knights
var piece = cb.Pieces[color][Knight] & ~cb.PinnedPieces;
while (piece != 0)
{
moves = StaticMoves.KnightMoves[BitOperations.TrailingZeroCount(piece)];
cb.UpdateAttacks(moves, Knight, color, kingArea);
tempScore += EvalConstants.MobilityKnight[BitOperations.PopCount((ulong)(moves & safeMoves))];
piece &= piece - 1;
}
// bishops
piece = cb.Pieces[color][Bishop];
while (piece != 0)
{
moves = MagicUtil.GetBishopMoves(BitOperations.TrailingZeroCount(piece),
cb.AllPieces ^ cb.Pieces[color][Queen]);
cb.UpdateAttacks(moves, Bishop, color, kingArea);
tempScore += EvalConstants.MobilityBishop[BitOperations.PopCount((ulong)(moves & safeMoves))];
piece &= piece - 1;
}
// rooks
piece = cb.Pieces[color][Rook];
while (piece != 0)
{
moves = MagicUtil.GetRookMoves(BitOperations.TrailingZeroCount(piece),
cb.AllPieces ^ cb.Pieces[color][Rook] ^ cb.Pieces[color][Queen]);
cb.UpdateAttacks(moves, Rook, color, kingArea);
tempScore += EvalConstants.MobilityRook[BitOperations.PopCount((ulong)(moves & safeMoves))];
piece &= piece - 1;
}
// queens
piece = cb.Pieces[color][Queen];
while (piece != 0)
{
moves = MagicUtil.GetQueenMoves(BitOperations.TrailingZeroCount(piece), cb.AllPieces);
cb.UpdateAttacks(moves, Queen, color, kingArea);
tempScore += EvalConstants.MobilityQueen[BitOperations.PopCount((ulong)(moves & safeMoves))];
piece &= piece - 1;
}
score += tempScore * ColorFactor[color];
}
// TODO king-attacks with or without enemy attacks?
// WHITE king
moves = StaticMoves.KingMoves[cb.KingIndex[White]] & ~StaticMoves.KingMoves[cb.KingIndex[Black]];
cb.Attacks[White][King] = moves;
cb.DoubleAttacks[White] |= cb.Attacks[White][All] & moves;
cb.Attacks[White][All] |= moves;
score += EvalConstants.MobilityKing[
BitOperations.PopCount((ulong)(moves & ~cb.Pieces[White][All] & ~cb.Attacks[Black][All]))];
// BLACK king
moves = StaticMoves.KingMoves[cb.KingIndex[Black]] & ~StaticMoves.KingMoves[cb.KingIndex[White]];
cb.Attacks[Black][King] = moves;
cb.DoubleAttacks[Black] |= cb.Attacks[Black][All] & moves;
cb.Attacks[Black][All] |= moves;
score -= EvalConstants.MobilityKing[
BitOperations.PopCount((ulong)(moves & ~cb.Pieces[Black][All] & ~cb.Attacks[White][All]))];
return(score);
}
