A certain block game
A cross-platform PSP emulator
Stream switch games to your PC via USB or network
UCI chess engine
Desktop/Android/HTML5/iOS Java game development framework
Cocos simplifies game creation and distribution with Cocos Creator
Home theater software and entertainment hub for digital media
The game engine for everyone
Multi-platform Engine for Desktop, XBOX (UWP) and Mobile games
Free game engine for development of desktop, mobile, and web games
Voxel game-creation platform with easy modding and game creation
scene-oriented, flexible 3D engine (C++, Python, C#, Java)
Multi-platform 2D and 3D game engine
Solar2D Game Engine main repository (ex Corona SDK)
lua dev plugin for unreal engine 4 or 5
SDL library for Android, including several games.
Android, UIQ 3.0, Series 60 Edition 5 open-source software
3D Engine c++
GemRB is a portable open-source implementation of the Infinity Engine
3D modeler, 3D game maker, 3D demo maker
GLScene Engine for Delphi & C++Builder VCL Windows 32/64
computer opponent for the board game Blokus
... the open-source glide computer