Larger/faster version of MultiItemVariationData

[behdad]

The following takes more spec, but is faster to parse, than the existing format1:

struct MultiItemVariationData
{
  uint8 Format; // 2
  uint16 regionIndexCount;
  uint16 regionIndexes[regionIndexCount];
  CFF2IndexOf<float[]> deltaSets;
};

[Lorp]

Please explain the benefit of using float here, rather than int16 or int32.

[behdad]

Please explain the benefit of using float here, rather than int16 or int32.

Good point. I'll measure the runtime and report.

[behdad]

Please explain the benefit of using float here, rather than int16 or int32.

Good point. I'll measure the runtime and report.

I tried int32.

I can measure about 6% speedup using floats. This is because the numbers need to be converted to float and multiplied by a float and added; I also have SIMD codepath for SSE and NEON for the float, but those seem to have very small effect.