fGranularity
while (size / fGranularity > kMaxSliderLimit)
fGranularity *= 2;
/ ((MaxPartitionSize() - 1) / fGranularity) + 0.5));
/ kMaxSliderLimit + 0.5) / fGranularity) * fGranularity;
SetValue(int32(1.0 * kMaxSliderLimit / fGranularity * size
/ ((MaxPartitionSize() - 1) / fGranularity) + 0.5));
uint32 fGranularity;
fGranularity(1),
unsigned fGranularity :1;