   Stopping Automatic Texture Generation
  OpenGL has a neat function to assign texture coordinates automatically with glTexGen. My problem is I want to apply this to only half of my mesh. (or only one side of the mesh) Can anyone tell me how I can do this? Thank you so much in advance.   
  I'm not sure I really understand the question, you can disable this feature the same way you enable it, with glDisable(GL_TEXTURE_GEN_[STQR]). So just draw half the mesh with this on, turn it off, and draw the other half. Or are you drawing your entire mesh in one DrawElements call and you only want to texgen for half of the coordinates? I wouldn't think you would be able to do that without splitting it into two draw calls.   