achieve reflective effects. A method often employed is called cube environment
mapping. The idea behind cube environment mapping is very simple. From an
object with a reflective surface you first generate six images of the environment
in each direction (front, back, up, down, left, right). That is, imagine placing a
camera at the center of the object and taking the size photographs of the world
around it in the directions specified. Based on the normal vector of the vertex in
consideration, the appropriate image is selected. This image is then projected
using planar mapping onto the object as shown in Fig.6.32.