Illumination map selector. Allows explicit selection of the illumination map to be used when rendering this material.
Enum. Set to -1 for automatic selection of the illumination map based on the value of catalog::Gloss.
Set to 0, 1, or 2 to select illumination map A, B, or C. The renderer will choose the closest illumination map available in the vignette.
-1 (automatic selection)