private static int GetMobility(Board board, Piece piece, byte[] targets)
{
int result = 0;
int row = 13 * PieceIndex(piece);
foreach (int square in targets)
{
Piece targetPiece = board[square];
int offset = targetPiece.IsColor(piece) ? 6 : 0;
result += MobilityValues[row + offset + Pieces.Order(targetPiece)];
}
//we return negative values if piece is black (black minimizes)
return((int)piece.Color() * result);
}