UCI chess engine
Open-source engine for Heroes of Might and Magic III
Multi Theft Auto is a game engine
Cross-Platform C++ 2D/3D game engine
Free game engine for development of desktop, mobile, and web games
Source code repository of the FreeOrion project
A game of dungeon exploration, combat and magic
Grow a Garden Script - Auto Farm, Infinite Seeds, Sell All
GUI for downloading/managing homebrew apps for video game consoles
Spring is a free RTS engine developed for Windows, Linux and Mac OS X.
Play any MIDI song on floppy drives !
Multimedia asset management and manipulator for Étoilé
A powerful chess engine written in C++
Multi-threaded 2D Renderer licensed under the Mozilla Public License
C++ Framework for slot machine games
A modern "graphics" API for text-based applications
Kinect based controller.