Unfortunately, you are unable to change texture mid vertex stream. This means you have to group the polygons together that use the same texture. The DrawIndexedPrimitve() method can be used to draw only parts of a vertex buffer. So you could do this:

+ Set the vertex buffer

+ Set the index buffer

+ Set a first texture

+ Draw some of the vertex buffer

+ Set a second texture

+ Draw some more of the vertex buffer

+ etc

I remember asking the exact same question when I first started using D3D. It is a pain in the butt.

Tessellator

You''re better off trying to seperate the rendering and the transformation part of your engine, for the simple reason that you''re probably end up drawing different textures/materials at different times (ie first the opaque, later the transparent) anyway.

For each object in my list I have a list of "face blocks" where each face block contains the material name, vertex data etc, and a pointer back to the actual object.. (clipping etc is done on a per object basis)..

Cheers,
Magnus