The speed of this tech doesn't exactly exceed 300fps like in the original Quake.
This is stencil buffered shadows along with DOT 3 BM and per pixel lighting in the new Doom engine. In game it is far from the screenshots. It's the most jawbrekaing experience for me.
Quake 1 and Doom 3 fans dig in:
BTW: it's all done in realtime
"On Geforce3 trilinear filtering is enabled by default (disabling it may make things faster) on other cards you can enable it by typing
"gl_texturemode gl_linear_mipmap_linear" it will help a lot to increase the visual quality of the game.
Finally so you can compare to something here are some of my experiences with Tenebrae's speed.
Some times from my system: Geforce4 Ti 4200, PIII 900, 256 Mb Ram
Speeds measured by using "timedemo demo1"
The average speed in 320*240 is 26.4 fps
The average speed in 640*480 is 25.6 fps (update v1.01 runs at 33.5 fps)
Tenebrae "should" run on a lot of graphics cards, first I will give some explanation about what card is best for tenebrae. (I don't say it's THE best card)
1) Geforce 3,4
These use only 2 passes per light and are the fastest cards to run tenebrae on.
2) Geforce 1,2
These require 6 passes per light and are decent cards to run tenebrae on.
Those others are actually ATI cards since those are the only ones that support all the necessary (ARB_)extensions for tenebrae. These cards span just like geforce cards several generations so performance may differ.
The average speed in 1024*768 is 21.5 fps"