Relief mapping

[Almos]

Let's face it - I suck at shader programming. For all the hours I've spent before the monitor trying to grasp the basic principles behind it, it was all to no avail. Therefore I cannot tell you exactly HOW relief mapping works - all I can tell you is that it does work, for mr. Oliveira was kind enough to make some example programs that utilise the technique and they can be downloaded from his web page (http://www.inf.ufrgs.br/~oliveira/RTM.html). Relief mapping surely looks good, even though it runs a tad slow on my Geforce 6800.

Happy marvelling at mr. Oliveira's genius, deciphering the principles he laid out in his paper (which is also downloadable), and perhaps using the technique for shading your own games.

Godspeed.

[Goz]

Isn't this the same as parallax mapping?

[juhnu]

It's a more advanced technique, but based on the same basic idea (=doing limited raytracing inside pixelshader). Most importantly the relief mapping allows self-shadowing, which the parallax mapping doesn't do.

[Kenneth Gorking]

It looks good it the screenshots, and thats the only place it looks good. The shadows are hard, and the technique exhibits some massive aliasing when viewed from steep angles (which is off course hidden from the screenshots). It also requires a preprocessing step of your normalmaps to use it. Bonzai software (http://www.bonzaisoftware.com/rtm.html) did a nice demo of an urban enviroment where you can walk around and have a close up look at the technique, there you can see the aliasing.
ATI did an article called Parallax occlusion mapping (http://www.ati.com/developer/techreports/2006/I3D2006/Tatarchuk-POM-SI3D06.pdf). You can just plug it in to your rendering pipeline without any preprocessing, it generates soft shadow and the geometry doesn't look flattened at steep angles.

[Almos]

And I thought something's bad with my graphics card... :)