An OpenGL RTS game engine written in C
Xash3D FWGS engine
SwiftShader is a high-performance CPU-based implementation
CGL (C Game Library) is a multipurpose library
Improved Quake III Arena engine
Lua Virtual Reality engine
Bloat-free Graphical User interface for C++ with minimal dependencies
Powerful development framework for creating virtually anything
realistic driving simulation + functions for 2D/3D graphics
3D driving simulation based on Open Dynamics Engine
A completely free, open-source, 2D game engine
mujoco-py allows using MuJoCo from Python 3
Cross-platform 2D and 3D game engine
Low-Level Game Engine for Retro Platforms
Display server for Linux based on Webkit and HTML layout capabilities.
Based on the raedwulf-et project
Multiagent simulator of road traffic in Qt/C++ and OpenStreetMap.
3D Software Renderer in 700 Lines
A really simple (following K.I.S.S statement) ray tracing project.