Anyone know what code it uses to generate it's tangents? You can't feed explicit tangents in, it does that stuff itself. If I can find it, I'll throw together an xNormal plugin to bake normal maps synced to Source.
Hah, so I did some testing and as far as I can tell, the default MikkTSpace gives out exactly the same result as the Source Engine synced version I wrote. Well, that was a nice excercise, at least...
Most studios/engines do(have a custom tangent basis) whether on purpose or by chance is another story. Most studios in my experience don't even know what "synced" means as far as normals, even Epic until recently didn't have a solution for synced bakes in UE3. So it would be much, much more surprising to me if Source is…
If I could just interrupt with some noob questions that get progressively off topic: When you say 1 smoothing group cube, do you mean a cube where all faces are smoothed + continuous (t net I guess) UV's, or a cube with no smoothing (all hard edges / split uv's)? If it's the former is the idea to show that the normals are…