Open source, lightweight, cross-platform 2D and 3D game engine implemented in C++ and released under the MIT license. Created by developers, for developers. U3D aims to give you the tools you need to stand up your game quickly, then experiment with and iterate on your game's design.
3D physics powered by Bullet Physics, and Box2D powering 2D. Rigid bodies, soft bodies, ragdoll characters and vehicles are directly in your control.