This node is a variant of the Semitransparent Surface (Surface-to-Surface Radiation Interface) node accounting only for specular reflection and transmission. Directional dependence of surface properties are calculated from Fresnel’s relations, using the refractive indices of adjacent domains. It is available when the Surface-to-surface radiation method is set to Ray shooting in the Surface-to-Surface Radiation interface settings. The node replaces the radiosity shape function for each spectral band on its selection with the explicit value of zero.

If diffuse reflection and emission should be considered, use the Semitransparent Surface (Surface-to-Surface Radiation Interface) node instead.

If pure specular reflection should be considered, use the Specular Mirror (Surface-to-Surface Radiation Interface) node instead.

If no radiation is transmitted through the surface, use the Opaque Surface (Surface-to-Surface Radiation Interface) node instead.

These settings are the same as for the Diffuse Surface (Surface-to-Surface Radiation Interface) node.

Physics tab with Surface-to-Surface Radiation selected: