Right, but note that performing step 2 with pygame.transform.rotate is not trivial, since it doesn't rotate about the origin, or any particular point for that matter: the fixed point of rotation depends on the surface dimensions and the rotation angle. So your step 2 is itself 3 steps.
For this reason, I generally anchor all my blits to the surface's center. In this case I would make it easy on myself by adding some margin to the image so that the desired rotation point is at the center of the image. I know not everyone likes to do it that way, though.
-Christopher
On Aug 20, 2012 4:32 PM, "Mark Wexler" <mark.wexler@xxxxxxxxx> wrote:To rotate around an arbitrary point,
1. subtract (vectorially) the center of rotation;
2. perform rotation (as if about the origin);
3. add the center of rotation.
Mark
On Mon, Aug 20, 2012 at 10:10 PM, Ricardo Franco
<ricardo.krieg@xxxxxxxxx> wrote:
> Hi, I need to rotate around a specific point.
> It's a person animation. So the arms should rotate over the shoulders'
> point.
> How to do that?
>
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