kPrefilterBandCount top-level constant Lighting and environment
int
const kPrefilterBandCount
Number of roughness bands in a prefiltered-radiance atlas (band 0 =
mirror, band kPrefilterBandCount - 1 = fully rough; band i covers
perceptual roughness i / (kPrefilterBandCount - 1)).
Must match kPrefilterBands in shaders/texture.glsl. The shader derives
its sampling lod from this constant alone, so a radiance cube always stores
exactly this many mip levels regardless of its face size.
Implementation
const int kPrefilterBandCount = 8;