Sub-surface scattering (SSS) refers to objects where light may enter from one point, have one or more scattering events and exit at another point on the surface. It can be considered as a special case of volumetric scattering.

Thea Render comes with a special model that contains all the used surface and media parameters together. Strictly using the most accurate model, you can create astonishingly realistic materials, ranging from milk and marble to plastics, that are only approximate in other high-end unbiased renderers.

Since Thea Render supports volumetric scattering, sub-surface scattering is supported out of the box (in unbiased mode). An approximate solution is available with the biased engine of Thea Render to yield fast results.