Cymric wrote:
However, one thing still intruiges me: Karlos, what are voxels? At some point, in the early 90's, German magazines were aflame with them. They would be the Next Big Thing, but apart from two games, the concept never took off. I know a pixel---picture element---and the texel---texture element, usually triangular. Voxel implies something with volume, but volume rendering is a slow and painstaking process. (At leaat, on the data visualisation programs I use.) Could you be so kind as to elaborate?
A Voxel is, as you describe, a volume cell. They are traditionally rather slow to render and for true 3D (ie perspective) are not so great, especially when a voxel is close to the point of view. It turns into a huge block of solid colour (shaded if you are lucky).
However, for isometric style projections, voxels can give very nice results, far better than polygons on pre-bumpmapping hardware like my trusty Permedia2...
-edit-
Hmm, that wasn't much of an elaboration, was it?
If you imagine you have a bumpy surface, you could create an image in which each 'pixel' represented the height of the surface at that point. This is a simple elevation map.
If you project that surface in 3D, and account for the physical width of these pixels (as well as their height) you can create a solid reconstruction of that surface.
Principal problems with voxels in 3D are that they look startlingly blocky up close and tend to involve a fair bit of overdraw (depending on the algorithms used to render them). Generally, they are not catered for by 3D hardware either, so you have to render them totally in software.
However, as I hinted, I have found a way to overcome that last part (albeit not really suited for perspective 3D) :-)
