Last Updated:
01
/
11
/
2005
Bump Map Compression
Almost all new video games are using bump mapping to some extent. While there is no doubt this improves the realism and visual complexity of scenes, the additional video memory consumed by having bump map textures for every surface can become problematic. The increasing popularity of the techniques that automatically generate normal maps from high resolution models further increases storage requirements because in this case normal maps cover the whole of each model without any reuse.
The DXT compression formats do a good job of compressing color textures, but were not designed for compressing normal map images. Now that programmable pixel shader hardware is commonplace, there are several different bump map storage formats available to developers, each with different trade-offs between storage and shader complexity. This whitepaper discusses the various options for compressing bump maps.
The whitepaper is accompanied by an FX Composer project that you can use to experiment with the bump map compression techniques described in the paper.
