Game Character Development with Maya

Appendix A. Normal Mapping in Maya

A technique used in many of today’s games is normal mapping. This is a method of making a low-polygon object or character appear to have more surface detail than it actually has, by collecting intricate lighting detail from a high-polygon version and applying it to the normals of the low one. Normals are the vectors (direction) a surface is facing.

Actually an application of bump mapping, normal mapping also works from a bitmap image. Normal maps are different from bump maps, however, in terms of the information they store. Bump maps work off a grayscale image that only registers changes in height; a normal map uses an RGB image, which contains enough information to store not only height but direction as well. ...