created: 08/17/00; revised 07/28/03, 10/20/05, 07/25/09, 10/10/09
The cross product is another operation that takes two vectors as operands. The most important use of the cross product in computer graphics is to find a vector perpendicular to a plane. This is needed when calculating how light reflects off the surface.
(Review: ) How many vectors are needed to define a plane that goes through a point?