I'm realizing that the .x format is not doing everything I want. Specificly I want to do more with material settings but still use ID3DXMesh to hold the actual mesh. So I'm trying to come up with a design and have a question about the index buffer. The index buffer doesn't actually have to be in any real specific order? Other then groups of three indicies need to form a triangle with clockwise winding. For example, the first set of indices is for a triangle facing front and the second set is for a triangle facing back. Once loaded into the mesh I can create a adjanency and then optimze the mesh in place.

Thanks, I would probably just stick with .x but messing around a bit with the Max SDK has got me interested in creating a exporter. Even if it will probably be functionally less advanced as the .x format.