public void TestFindFirstSquareIndexAndFindFirstSquareIndexInternal(long value, int expectedResult)
{
var bitboard = new Bitboard(value);
var firstSquareIndex = bitboard.FindFirstSquareIndex();
Assert.That(firstSquareIndex, Is.EqualTo(expectedResult));
var firstSquareIndexInternal = Bitboard.FindFirstSquareIndexInternal((ulong)value);
Assert.That(firstSquareIndexInternal, Is.EqualTo(expectedResult));
}
public void TestFindFirstSquareIndexAndFindFirstSquareIndexInternalWhenSingleBitIsSet()
{
for (var index = 0; index < ChessConstants.SquareCount; index++)
{
var value = 1L << index;
var bitboard = new Bitboard(value);
var firstSquareIndex = bitboard.FindFirstSquareIndex();
Assert.That(firstSquareIndex, Is.EqualTo(index), "Failed for the bit {0}.", index);
var firstSquareIndexInternal = Bitboard.FindFirstSquareIndexInternal((ulong)value);
Assert.That(firstSquareIndexInternal, Is.EqualTo(index), "Failed for the bit {0}.", index);
}
}
public void TestFindFirstSquareIndexAndFindFirstSquareIndexInternalWhenNoBitsAreSet()
{
Assert.That(Bitboard.NoSquareIndex, Is.LessThan(0));
const long Value = 0L;
var bitboard = new Bitboard(Value);
var firstSquareIndex = bitboard.FindFirstSquareIndex();
Assert.That(firstSquareIndex, Is.EqualTo(Bitboard.NoSquareIndex));
var firstSquareIndexInternal = Bitboard.FindFirstSquareIndexInternal(Value);
Assert.That(firstSquareIndexInternal, Is.EqualTo(Bitboard.NoSquareIndex));
}
private static Bitboard GetSlidingAttackers(
int targetSquareIndex,
Bitboard opponentSlidingPieces,
Bitboard[] slidingAttacks,
Bitboard emptySquareBitboard,
bool findFirstAttackOnly)
{
if (!opponentSlidingPieces.IsAny)
{
return(Bitboard.None);
}
var result = Bitboard.None;
var slidingAttack = slidingAttacks[targetSquareIndex];
var attackingSlidingPieces = slidingAttack & opponentSlidingPieces;
var currentValue = attackingSlidingPieces.InternalValue;
while (currentValue != Bitboard.NoneValue)
{
var attackerBitboard = Bitboard.PopFirstSquareBitboardInternal(ref currentValue);
var attackerSquareIndex = Bitboard.FindFirstSquareIndexInternal(attackerBitboard);
var connection = GetConnection(targetSquareIndex, attackerSquareIndex);
if ((emptySquareBitboard & connection) != connection)
{
continue;
}
result |= new Bitboard(attackerBitboard);
if (findFirstAttackOnly)
{
return(result);
}
}
return(result);
}
