sssapprox

bsdf  sssapprox(vector albedo, float meanFreePath, float roughness, float scale, ...)

albedo

Average surface reflectance.

meanFreePath

Average distance between scattering events.

roughness

A value from ‘0.0’ to ‘1.0’ blending to an ideal diffuse transmission reflectance profile.

scale

Physical scale of the material. Smaller scale values will make the material more transmissive.

See writing a PBR shader for information on BSDFs.

Models SSS illumination based on an approximate reflectance profile.