SonicGDK Windows, Mac game
SonicGDK (short for 3D Sonic Games Development Kit) is a codebase, a collection of source codes, which allows anyone to create 3D platformer video games based on the Sonic the Hedgehog franchise. It can be freely modified and is integrated with the UDK...
Nvidia Geforce D Sonic Games Development Kit Unreal Development Kit Sonic Games Development Kit Shader Model Video Game
Source: moddb.com