Carmack's MegaTexture
Gamer Within has a two page Q&A with John Carmack. It covers his new MegaTexture technology used in Enemy Territory: Quake Wars.
The idea behind MegaTexture is to use one giant texture to cover the entire terrain. The example given in the article is 32,000 by 32,000 pixels. Current video cards obviously can't directly use this texture to render the terrain, but this does allow game artists to create very detailed terrains.
The article doesn't provide any technical coverage of the technique, but it is still an interesting read. Here's a quote that caught my attention concerning terrain rendering:
Geometry level of detail on terrain…there have been thousands of papers written about it, and I honestly don’t think it’s all that important. The way the hardware works, you’re so much better off setting down a static mesh that’s all in vertex and index buffers, and just letting the hardware plow through it...
I remember spending a lot of time a few years ago trying to figure out things like ROAM for rendering terrain. Even back then it was usually faster to just dump all of the triangles on the video card and let it sort them out.
The screen shots in the article look great. I can't wait to try this out in person.