3D Procedural Game Engine Using OpenGL
A modern, cross-platform Quake game engine based on FitzQuake.
DOOM / Heretic / Hexen source port with enhanced graphics and UI
An advanced RPG-specific Game Engine
A basic 3D environment with a first-person POV
Smokin' Guns - unofficial release for Mac OS 10.5
First-person game engine
Reference implementation for the Doom game engine.
Game engine supporting many 3D/2D formats and graphic effects