Open Source real-time strategy game engine for early Westwood games
Desktop/Android/HTML5/iOS Java game development framework
A simple and easy-to-use library to enjoy videogames programming
Open source clone of the Age of Empires II engine
Fast PlayStation 1 emulator for x86-64/AArch32/AArch64
Cross-Platform C++ 2D/3D game engine
The Open Toolkit library is a fast, low-level C# wrapper for OpenGL
scene-oriented, flexible 3D engine (C++, Python, C#, Java)
2D game development library for Ruby and C++
dhewm 3 main repository
3D Procedural Game Engine Using OpenGL
Gideros Release version
Retro game engine for creating games like it's 1997
GemRB is a portable open-source implementation of the Infinity Engine
Orx: Portable Game Engine
RTS game with the theme of Strategy by Design
Parabator 2 - Free 3d board game
A modern, cross-platform Quake game engine based on FitzQuake.
Opensource crossplatform Fallout 2 game engine writen in C++ and SDL
A cross-platform port of Hexen II game.