CGO heeft een bump mapping artikeltje in elkaar gezet, met uiteraard weer een paar relaxte bump mapping screenshots. Hier heb je een stukje over emboss bump mapping vs environment bump mapping (die nieuwe hitsige feature van de G400):
These two methods each have their benefits and drawbacks. Emboss bump mapping is probably easiest to implement, and is supported by nearly all modern video cards. The impact on 3D performance depends on how many things in a scene are bump mapped, but it is generally the same as any other multi-pass rendering effect. The performance penalty is likely to range between 10-30%. Environment Mapped Bump Mapping is currently only possible through DirectX 6.0 or later. It's also currently only supported in hardware by Matrox's G400 series. It does, though, generally produce more pleasing results than the emboss method, and is more flexible. The emboss method only really works properly with one light source, but EMBM can more easily handle multiple lights. It also calculates the bumps on a per-pixel basis, whereas the shifts required to produce the bumps using the emboss method are calculated per vertex (corner of a polygon). This means that the height/depth of a bump can vary more using the EMBM method. Probably most important, the bump map doesn't need to be re-calculated with every frame drawn. Because of this, EMBM has about the same impact on performance as emboss bump mapping, despite the addition of a new texture (the environment map).