I have been using the libGDX API in Java for some years now, creating small 2D games as a hobby. Some months ago, I decided to start getting into the 3D side of things, but this area seems to be very undocumented and the development community doesn't seem to be much focused on it.
I decided to start my own libGDX 3D framework (which can be found here) in an effort to solve the problems that I saw within the 3D API, making it easier to use for me and for everyone else. Everyone loves the entity system within the Unity3D engine, so I decided to go down this route. The framework has been a complete success so far, implementing a first-person controller, skyboxes, and lighting. However, implementing physics such as rigid bodies and collision detection has proven to be a challenge.
Contributors are totally welcome to help tackle this problem since I'm very eager to have this thing released for game developers.