[ggggtez]

I think this is a good reference for anyone who touches computer graphics. It's not really clear enough for Physics (see all the comments here), but as tips for understanding how computer tend to model things, it's fine.

For example, a raytracer can simulate specular (mirror) or diffuse (matte) reflections by simply playing with the incident angle when the ray hits an object. The more jitter, the more matte the object appears. Similarly, you can get very nice "milk" or "skin" coloration by following the incoming ray slightly below the surface before reflecting back out, the same way this discusses having a thin layer of water would prevent some of the light from reflecting back out.