UnityGame/Library/PackageCache/com.unity.inputsystem/InputSystem/Utilities/DynamicBitfield.cs
2024-10-27 10:53:47 +03:00

70 lines
1.9 KiB
C#

using UnityEngine.InputSystem.Utilities;
namespace UnityEngine.InputSystem
{
/// <summary>
/// Struct replacement for System.Collections.Bitfield.
/// </summary>
/// <remarks>
/// We don't want the extra heap object just for keeping the header
/// state of the bitfield. This struct directly embeds the header
/// into the owner. Also doesn't allocate any array while length is
/// less than or equal to 64 bits.
/// </remarks>
internal struct DynamicBitfield
{
public InlinedArray<ulong> array;
public int length;
public void SetLength(int newLength)
{
// Don't touch array size if we don't have to. We're fine having a
// larger array to work with if it's already in place.
var ulongCount = BitCountToULongCount(newLength);
if (array.length < ulongCount)
array.SetLength(ulongCount);
length = newLength;
}
public void SetBit(int bitIndex)
{
Debug.Assert(bitIndex >= 0);
Debug.Assert(bitIndex < length);
array[bitIndex / 64] |= 1UL << (bitIndex % 64);
}
public bool TestBit(int bitIndex)
{
Debug.Assert(bitIndex >= 0);
Debug.Assert(bitIndex < length);
return (array[bitIndex / 64] & (1UL << (bitIndex % 64))) != 0;
}
public void ClearBit(int bitIndex)
{
Debug.Assert(bitIndex >= 0);
Debug.Assert(bitIndex < length);
array[bitIndex / 64] &= ~(1UL << (bitIndex % 64));
}
public bool AnyBitIsSet()
{
for (var i = 0; i < array.length; ++i)
{
if (array[i] != 0)
return true;
}
return false;
}
private static int BitCountToULongCount(int bitCount)
{
return (bitCount + 63) / 64;
}
}
}