For immersive environments a more useful image
format are cubic maps, that is, the six 90 degree
perspective projections from the current camera position
to each face of a unit cube centered on the camera. This is
not a new idea for games or virtual reality applications
which have long employed cubic maps to create high
quality backgrounds or environmental lighting [13]. If all
six cubic maps are available then the entire visual field is
defined and therefore any projection geometry can
potentially be created, it is simply a image transformation
exercise. For most immersive displays not all six cubic
faces are required