A multi core friendly rigid body physics and collision detection lib
Cocos simplifies game creation and distribution with Cocos Creator
Cross-platform 2D and 3D game engine with modular architecture
Multi-platform 2D and 3D game engine
A game engine with an emphasis on real-time cutting-edge solutions
Descent 3 by Outrage Entertainment
An open source flight dynamics & control software library
Open 3D Engine (O3DE) is an Apache 2.0-licensed multi-platform 3D
Multi-platform Engine for Desktop, XBOX (UWP) and Mobile games
Soft-body physics simulator
Game/Scene Development System
Enigma is a puzzle game
A free 3D game engine to create games and realtimes scenes for Windows
MIT Licensed Open Source version of Torque3D from GarageGames
Real-time collision detection and multi-physics simulation for VR
Spring is a free RTS engine developed for Windows, Linux and Mac OS X.
Vivid is a modern C++ 3D engine using OpenGL4+
OpenGL port of the classic 6dof 3D shooter Descent
Amazon Lumberyard is a free AAA game engine
3D C++ Game Engine - yet another open source game engine