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View Full Version : Scaling then Rotating



09-26-2000, 09:10 PM
1)Let's say 0,0,0 is my center and i translate to 100,100,0. Now I want to rotate like the moon rotates around the earth around 0,0,0. What i do is translate to 0,0,0, rotate, translate back. That works fine.
2)Next, I add in a glScalef(2.0,1.0,1.0)
The result of this is what i expect, a slightly distorted object along the x object in the 2nd quadrant.
3) However, if i do the translate to 100,100, then scale, then rotate (in "2" i did TRS), my object ends up way on the left hand side of the screen aligned with the x axis.
4)If i were to scale uniformally (i.e. 2,2,2) everything works no matter what order i do it in.

Any idea WHY this happens? Does scaling non-uniformally mess up orthogonal axes?

P.S. My object is a pyramid if that matters, although i dont think it should.

Antonio
09-27-2000, 10:47 AM
I think it would be better if you posted the sequence of operations. There are things which are not clear from your description, like what rotation you are using.

Antonio www.fatech.com (http://www.fatech.com)