Normalized diffusion profile for subsurface scattering rendering

摘要

The disclosure provides an approach for rendering images which include subsurface scattering effects. In one aspect, a shader computes subsurface scattering effects via a ray-tracing or point-based technique using a normalized diffusion profile. The shader may use the inverse of a cumulative density function associated with the normalized diffusion profile to determine, for each ray intersecting the surface, points on the surface at which to evaluate the normalized diffusion profile. To determine the lit surface of a pixel due to subsurface scattering, the shader may multiply the result of the integral of the normalized diffusion profile for each of the R, G, and B color components by corresponding components of a diffuse color constant. Further, the shader may scale the integral of the normalized diffusion profile based on a scaling function which accounts for a forward-scattering nature of a medium and compensates for out-of-plane scattering.