When you look at a normal map, it is generally a blue and purple color. We already covered texturing in GLSL in a previous tutorial, so I won’t go over it again. How does bump mapping work in OpenGL with GLSL though? GLSL texturing works on a per-texel basis, where a texel can be thought of as a scaled pixel, either larger or smaller, and we get access to a texel at any fragment on an objects surface when we are texturing in GLSL. This gives our applications a greatly added sense of realism. This means that we can apply standard lighting techniques that require a normal value on a per-pixel basis instead of a per-vertex or per-surface basis.
Bump mapping works by taking an image which stores surface normals on a per-pixel basis. Would you like to know the best thing about it? It is extremely simple to implement. Bump mapping is essential in todays computer games, and computer graphics in general.
