public bool TryGetAt(byte[] image, uint index, ref int pOffset)
{
if (index >= _nElements)
{
return(false);
}
uint offset = 0;
if (_entryIndexSize == 0)
{
int i = (int)(_baseOffset + (index / _blockSize));
offset = NativeReader.ReadByte(image, ref i);
}
else if (_entryIndexSize == 1)
{
int i = (int)(_baseOffset + 2 * (index / _blockSize));
offset = NativeReader.ReadUInt16(image, ref i);
}
else
{
int i = (int)(_baseOffset + 4 * (index / _blockSize));
offset = NativeReader.ReadUInt32(image, ref i);
}
offset += _baseOffset;
for (uint bit = _blockSize >> 1; bit > 0; bit >>= 1)
{
uint val = 0;
uint offset2 = NativeReader.DecodeUnsigned(image, offset, ref val);
if ((index & bit) != 0)
{
if ((val & 2) != 0)
{
offset = offset + (val >> 2);
continue;
}
}
else
{
if ((val & 1) != 0)
{
offset = offset2;
continue;
}
}
// Not found
if ((val & 3) == 0)
{
// Matching special leaf node?
if ((val >> 2) == (index & (_blockSize - 1)))
{
offset = offset2;
break;
}
}
return(false);
}
pOffset = (int)offset;
return(true);
}
