Cross-Platform C++ 2D/3D game engine
An OpenGL RTS game engine written in C
Xash3D FWGS engine
Zig game engine & graphics toolkit
Voxel game engine in C++ with OpenGL
Vulkan renderer mod for Minecraft
scene-oriented, flexible 3D engine (C++, Python, C#, Java)
The Open Toolkit library is a fast, low-level C# wrapper for OpenGL
3D Engine c++
A Minecraft mod designed to improve frame rates
A modular Common Lisp game engine
3D Procedural Game Engine Using OpenGL
Game engine supporting many 3D/2D formats and graphic effects
Open source clone of the Age of Empires II engine
A free and open-source Touhou Project fangame
GemRB is a portable open-source implementation of the Infinity Engine
A modern, cross-platform Quake game engine based on FitzQuake.
GLScene Engine for Delphi & C++Builder VCL Windows 32/64
Orx: Portable Game Engine
0 A.D. is a free, open-source, cross-platform real-time strategy game.
A cross-platform port of Hexen II game.
Open source FPS/RTS Game