Iterative Parallax Mapping with Slope Information

This paper improves per-pixel displacement mapping algorithms. First we review the previous work including bump, parallax, and relief mapping, and also sphere tracing. Then we propose a new iterative algorithm based on parallax mapping, which takes into account the surface slope represented by the stored normal vector. We show that the new method is much better than parallax mapping, however a little poorer than relief mapping, in terms of image quality. However, it is much faster than relief mapping, and is thus a good candidate for implementation in games.