This past week as part of Epic Games making UE4 free to developers they managed to get NVIDIA to let them open up some of the PhysX source code as PhysX is depended upon by Unreal Engine 4 for physics handling. NVIDIA this past week ultimately opened up their entire PhysX SDK to everyone.

This news is a bit late, but NVIDIA announced via their developer blog that the PhysX 3.3.3 source code is now available for free on GitHub, though it's not under a free software license and requires developers to consent to NVIDIA's EULA.

NVIDIA is opening PhysX in hopes of accelerating its adoption, lowering the barrier to entry, etc. Along with the PhysX SDK, the Clothing and Destruction libraries are also now open. The code with full source is available for Windows, Linux, OS X, and Android.

To gain access to the PhysX source, follow's NVIDIA process for gaining access on GitHub.