Rendering from Compressed Textures
We present a simple method for rendering directly from compressed textures in hardware and software rendering systems. Textures are compressed using a vector quantization (VQ) method. The advantage of VQ over other compression techniques is that textures can be decompressed quickly during rendering. The drawback of using lossy compression schemes such as VQ for textures is that such methods introduce errors into the textures. We discuss techniques for controlling these losses. We also describe an extension to the basic VQ technique for compressing mipmaps. We have observed compression rates of up to 35:1, with minimal loss in visual quality and a small impact on rendering time. The simplicity of our technique lends itself to an efficient hardware implementation.