Gamastra heeft een artikel gepost genaamd "the Ups and Downs of bumpmapping with DirectX6". Hier heb je een stuk handige info over wat bumpmapping is:
You may be asking, "I’ve never used a modeling package – what is bump mapping?" First, I should explain that the way bump mapping is implemented under DirectX 6 is not what purists would call "real" bump mapping. If you asked Jim Blinn to tell you about bump mapping (and he would know, as he invented it), he would likely tell you it’s different than what I’m about to present. Blinn would tell you that bump mapping adds surface detail (bumpiness) to objects in 3D scenes, without adding more geometry than already exists. It does so by varying the lighting of each pixel according to values in a bump map texture. As each pixel of a triangle is rendered, a lookup is done into a texture depicting the surface relief (a.k.a. the bump map). The values in the bump map are then used to perturb the normals for that pixel. The new bumped-and-wiggled normal is then used during the subsequent color calculation, and the end result is a flat surface which looks like it has bumps or depressions in it.
Nou is het probleem dat echte 'textbook' bumpmapping op dit moment niet mogelijk is omdat de hardware en APIs (DX6) er niet geschikt voor zijn. In plaats van 'textbook' bumpmapping gebruikt DX6 emboss effecten of het betere environment-map bumpmapping (op dit moment alleen ondersteund door de Matrox G400). In het artikel van Gamasutra vind je veel info over beide methodes. Check 't hier.
