3D Coding TAT - Voxel Landscapes
I believe this technique was first used for medical purposes (ultra-sound or something...). In many ways it is identical to patchwork landscapes where only a coarse resolution is used to describe every 100th or 1000th point height across the landscape. The problem with patchwork is that to get a reasonable looking landscape you need to use many corner points to allow a good level of resolution and decent fine detail. But the more vertex corner points are used the greater the storage and the greater the CPU workload. It's a bit like digitizing sounds as digital samples. Use too few samples and the sound is terrible, use too many and memory rapidly sky rockets.
Unlike patchwork, in Voxel landscapes the height difference between corners are interpolated in a NON-LINEAR fashion. That is, they are curved to give the impression of a smooth, rolling landscape rather than a bed of nails. The important thing to remember is that these curved edges between corner vertices are calculated and drawn in REAL-TIME. So given 3 or 4 vertex points a quick curve is approximated and drawn to the desired scale. The sub-divisions between each vertex are NOT stored, but must be calculated. This does require more CPU time than a flat patchwork landscape, but the result is usually much more realistic and it is possible to get away with less corner points unlike the patchwork method which often needs many corner points to help iron out the jagged spikes.
I think the word 'Voxel' means Volumetric Pixel or something like that.