US Patent 7786993 Environment mapping

A system and method for environment mapping determines a computer-generated object's reflective appearance, based upon position and orientation of a camera with respect to the object's location. An embodiment of the present invention is implemented as a real-time environment mapping for polygon rendering, however, the scope of the invention covers other rendering schemes. According to one embodiment of the present invention, a vector processing unit (VPU) uses a modified reflection formula—r=e−(e·(n+eo))(n+eo)/(1−nz)=e−(e·[nx, ny, nz−1])[nx, ny, nz−1]/(1−nz), wherein eo=[0,0,−1], and nx, ny, and nz are the components of the surface normal vector n—to compute reflective properties of an object.