3D Procedural Game Engine Using OpenGL
Cross-Platform C++ 2D/3D game engine
The open-asset-importer-library repository
Flax Engine, multi-platform 3D game engine
Open 3D Engine (O3DE) is an Apache 2.0-licensed multi-platform 3D
scene-oriented, flexible 3D engine (C++, Python, C#, Java)
Powerful, mature open-source cross-platform game engine for Python
GemRB is a portable open-source implementation of the Infinity Engine
An unmodified version of the MMORPG Impressive Title by KovuLKD
A free 3D game engine to create games and realtimes scenes for Windows
An isometric arcade-style game of skill, puzzles and exploration
C++ lightweight cross-platform game engine
Arkham Development Open Source Projects
3D Scene Builder
Vivid is a modern C++ 3D engine using OpenGL4+
Spring is a free RTS engine developed for Windows, Linux and Mac OS X.
DOOM / Heretic / Hexen source port with enhanced graphics and UI
3D Game engine with editor
A 2D game engine and level editor
Cross-platform 2D and 3D game engine
Opensource Game Studio