HoverInc Stratified samples

[gkjohnson]

Fix #449

TODO

• Comparison images
• Reduce swirling effect
  • This is a artifact of each shape sampling algorithm and the correlation between X and Y.
  • Possibly using a 4 color blue noise seed this can be helped
  • Possibly reshuffling the strata more intelligently would help
  • * Use a 3d texture with X: full strata for one sample, Y: new strata per id, Z: new strata per bounce
  • * Strata doesn't need to be regenerated until wrapping around?

NOTES

• Doesn't work with "stableNoise" (requires predictable randomness) (punt)

[gkjohnson]

The stratification approach seems to turn bright spots into swirls. This occurs when using a PCG random seed, as well, so this seems to be a function of the stratification approach.

[gkjohnson]

	Before	After
1 sample
10 samples
50 samples

[gkjohnson]

NEW 10 samples	Before	After