Stunt Rally uses a plugin of OGRE called “CgProgramManager”. This plugin is itself free software. But its only purpose is to interface the Cg Toolkit from NVIDIA which is a BLOB, a piece of non-free software, closed source, locked-down, propritiary, however you want to call that. So if you do not have this BLOB installed, the CgProgramManager is useless.
Now I want to ask: How much does Stunt Rally depend on Cg? Could Stunt Rally do without it? Could something replace it and how hard would that be? And especially: Could I build a working Stunt Rally without the NVIDIA Cg toolkit?
For those who don’t know: Cg is a shader language by NVIDIA. The problem with Cg is that AFAIK there is currently not any free software around which “speaks” Cg natively; the only useful tools come from NVIDIA and these are BLOBs, pieces of non-free … you get the idea.