   How to set different subset of one mesh?
  In directX, I use cylinder to render tree's branches, now I want to use two textures to map different branches.For example, use tex1 to map the 2nd level branch and use tex2 to map the other branches.  My idea is : put the 2nd level branch into subset0 and the other to subset1.  For a regular object,like cube, it's easy to put different faces to different subset. The problem I meet is: how to differentiate the triangle faces are the 2nd level branch's?   
  I'm not sure if this is a new problem or a cross posting of this and/or this thread, but in any case it's not really a Game Design problem.Moving to DirectX/XNA   ;  If you're using 3dsmax, you can set the subset in Face Edit mode. I think it's called Material ID or something similar.   