Silhouette maps for improved texture magnification

Texture mapping is a simple way of increasing visual realism without adding geometrical complexity. Because it is a discrete process, it is important to properly filter samples when the sampling rate of the texture differs from that of the final image. This is particularly problematic when the texture is magnified or minified. While reasonable approaches exist to tackle the minified case, few options exist for improving the quality of magnified textures in real-time applications. Most simply bilinearly interpolate between samples, yielding exceedingly blurry textures. In this paper, we address the real-time magnification problem by extending the silhouette map algorithm to general texturing. In particular, we discuss the creation of these silmap textures as well as a simple filtering scheme that allows for viewing at all levels of magnification. The technique was implemented on current graphics hardware and our results show that we can achieve a level of visual quality comparable to that of a much larger texture.