Though im not as active anymore, i have done some work on idtech 4.
Im using code pieces of darkmod to update the old code to more modern standards like AVX and AVX2 SSE* intrinsics, and im using a correct floating point mask for setting precision for both
x87 and SSE codepaths. The SMP changes from darkmod have also made it in, and the game runs a lot better now (no microstutter whatsoever).
The async thread code was also updated a lot as part of the SMP changes and i made a few additions myself.
Loads of dead and unused code was removed (more there than most would think), and im using a hybrid GLSL ARB2 renderer.
The interactions are done with GLSL the rest like shadows and materials are still handled by the old ARB2 shaders.
Since the engine code im using was originally from MH's minimal Doom3, there are no longer any editors in the executable (this is both good and bad).
The old hardware gamma code was modified to include gamma clamping, since thats a restriction on windows > win2k.
Codepaths for 4:3 16:9 and 16:10 resolutions have been added, but you need a menu gui like venoms to have easy access to the new resolutions.
The render debugger was updated substantially with code from fhdoom.
If not enabling things like SSAO or soft shadows, this engine can push close to 60 FPS on ultra settings with vsync on in sikkmod.
The reason it does not work so well with SSAO and soft shadows is the fact that sikkmod uses a hacked depthrenderer to get the nessesary depth capture,
so basically it draws everything twice... Also these effects newer worked to well so dont use them.
But everything else you can have on
Productivity is a state of mind.