Bidirectional texture function
From Wikipedia, the free encyclopedia
Bidirectional texture function (BTF) is a 6-dimensional function depending on planar texture coordinates (x,y) as well as on view and illumination spherical angles. In practice this function is obtained as a set of several thousands images of material sample taken during different camera and light positions. Such images are subsequently rectified and compressed using various methods.
Its main application is photorealistic material rendering of objects in virtual reality systems.
