.CRF File Extension

Three-dimensional materials file created in the Cal3D binary materials format; stores references to the graphics that are overlaid on 3D meshes to provide the model's surface appearance; also stores ambient, diffuse, specular, and shininess lighting properties.

CRF files are the binary version of .XRF format, which stores the material references and properties in an XML format.

Cal3D is an open source 3D character animation library written in C++.