I've pushed SimKit (my 3D rendering code I've been working on) to git. It's a work-in-progress, and doesn't even have any renderers or material system code written yet. But it's designed to be a fairly good 3D engine for doing game development in C++. Maintaining this is the reason why I had no February 1GAM release, and why March will similarly be absent barring a miracle.
The license is currently LGPLv3. Contributions will be accepted upstream but only if accompanied with copyright transfer or a full nonexclusive royalty-free worldwide license. This is because I may either sell exceptions or change the license to something more liberal in the future (more information in the COPYING file). You may use the code right now by checking it on GitHub at: https://github.com/kmeisthax/SimKit