   2 .X file, load in the same code, but result not the same, why
  the code is in c#   device.Transform.World = Matrix.RotationY(Environment.TickCount / 1000.0f)I model a sphere in 3ds, I move the sphere to 0,0,0, export to sphere.3ds file, and convert to .x file, load inside my code, the sphere rotate on it''s pivot point -- spin by itself.then I move the sphere to 0, 10, 0, export to sphere.3ds, overwriting the previous file, convert and load inside my code, now the sphere rotate around a point -- spin around some imaginary point.What is wrong with it, please advise, thanks 
  ...Wow......I don''t think I''m even going to answer that... ;  why not, is the question rediculous? ;  um, i only see one line of code?    ;  i think the code doesn''t matter at all, the problem is about the 2 .x file one exported with x=0, y=0, z=0 and one exported with x=0, y=10, z=0load inside a standard code -- from directx tutorial, and the result is not the same ;  Yes, the question is rediculous.It is rotating around an imaginary point because that''s what you told it to do  . Think about it... If you have an object at 0,10,0 and tell it to rotate around the origin then of course it''s going to rotate around the origin! Your object is not automatically centered when it is exported, if that''s what you were thinking. ;  ok, so what if i want the  object at 0,10,0 to rotate on a point but not around a point, how can I do it?translate to the origin? ;  First of all, it''s good practice to model objects around the origin. It will save common sense headaches like this one. Second, rotations should be done before   translations if you want them to rotate in place instead of around a point. ;  ok, thank you very much, I will try it out 