Bidirectional texturing function

A BTF ( bidirectional texture function , bidirectional Texturierungsfunktion ) is in the computer graphics , a distribution function , based on the descriptions of surfaces ( " Textures relates") that not only the reflection properties capture at a particular point, but the illumination and viewpoint-dependent behavior of the entire surface structure included. It represents an extension of the bidirectional reflection distribution function (BRDF). In contrast to the textures based on two-dimensional "decals" , a high degree of realism is achieved under changing lighting.