isSquareAttacked method
Is sq attacked by any piece of byColor, given current occupancy?
Implementation
bool isSquareAttacked(int sq, int byColor) {
// Pawns: a square is attacked by byColor pawns from the opposite pawn's
// capture pattern.
if ((pawnAttacks[byColor ^ 1][sq] & pieces[byColor][pawn]) != 0) return true;
if ((knightAttacks[sq] & pieces[byColor][knight]) != 0) return true;
if ((kingAttacks[sq] & pieces[byColor][king]) != 0) return true;
final bishopsQueens = pieces[byColor][bishop] | pieces[byColor][queen];
if ((bishopAttacks(sq, occAll) & bishopsQueens) != 0) return true;
final rooksQueens = pieces[byColor][rook] | pieces[byColor][queen];
if ((rookAttacks(sq, occAll) & rooksQueens) != 0) return true;
return false;
}