   Select skin produced by GPU
  Maybe It's not a good choiceto to use GPU skin methord without Shader 3.0!    After I had carried out my GPU skin by shader 2.0,I found there was many problem waiting for me! For Instance,If you want to implement a picking  tools for you Editor,you will find that picking the skin mesh is a big problem. Because the  positions of vertices was calculated in the vertex shader,the application can't get the values at all;So you have to recalculate them in the application .Obviously it not a good idea .Do you have any good advice?[Edited by - aliascz on January 22, 2008 12:13:38 AM]
  It depends on how precise you need the picking to be.  This kind of operation is normally done on bounding volume geometry and not on the actual rendered mesh.  For example, is it really important to know which eye a bullet hit or just that it hit the head?AABB's (Axis-Aligned Bounding Boxes) are one of the easier volumes to implement.  You would create a box that completely surrounds the mesh and smaller boxes that surround different parts.Your ray intersection tests would first see if you hit the large box surrounding the object.  If so, continue testing against the smaller boxes until you find the part of the mesh that's actually hit. Granted, this might not be exact if you don't skin the boxes, but depending on your needs, it might be close enough.neneboricua   