This function emulates a surface similar to velvet or moss, and is similar to a Fresnel calculation. Incidentally, it is also useful for shader effects such as a scanning electron microscope.
Takes in a texture to be used as the diffuse color.
Takes in a normal map used to perturb the surface of the fuzzy result.
Value used to darken the object wherever its normals become parallel to the camera, generally toward the center. The higher the number, the darker the core. Default is 0.8.
Controls the rate of falloff from the core to the edge. Default is 6.0.
Controls how bright the surface becomes as its normals become perpendicular to the camera, generally toward the edges.