Changing the centre of a shape keyed object / Sharing IPO's

How do I get objects to share IPO’s? The problem is that Ive been animating this object using shape keys but after defining the keys I realised I need to change the centre of the object but it dosent allow me to.

One solution is to create a copy of the Ipo Curve and assign it to a new object with the centre correctly aligned. But then I dont know if I can copy the shape too.

So any smart solution to change the centre of the object without having to redo everything?

Thanks a lot…Kinda stuck


Use an empty. Add one of those, then place it where you’d like the new center. Then, parent the object to the empty (select object, select empty, ctr+p). Then, go to the IPO window. For the empty, select to use the same IPO as the object, then press the little number near the IPO name (make single user). You now have a copy. Then, select the “object” curves for the object - loc, rot, scale, and delete those. That should do it. Now you have position animated on the empty, and the shape on the object. The object follows the empty around.

Once you start this process, don’t change the current frame. Don’t scrub the timeline.

Hey thanks a lot! Yes it does work but there’s a sizing problem. The moment i hit alt+a the entire object resizes to a very miniscule size…I think its because of coping the scaling or something…Im uploading the .blend…Could you please look into it? I cant figure it out.

P.S. The empty needs to be rotated about the x-axis by 90 before parenting. Scaling is a mystery…
[edit] the new centre needs to be at the exact centre of the object…As of now its at the centre of the rear face.


Docomo3.blend (140 KB)

Ah, as I suspected - you have a scaling IPO going on on the object. If you hit N in a 3D View, you can see the transform panel. Look at ScaleX, Y Z. It’s set at 0.1. (Just like the X rotation is set to 90).

Normally, you’d want to “center new” and “apply scale / rotation to obData” to solve this - but you’re right, you can’t do that with shape keys on the object.

I just tried - a sequence of editing steps that does what you want is:

  • Add empty.
  • Set its IPO to ObIPO.
  • Unlink the object’s link to ObIPO by selecting the object, then pressing the X next to “obIPO”.
  • Scrub once - the empty will snap to the animated position and scale. (Have a look at the N panel).
  • Then, put the playhead at frame 50 or so (after the animation).
  • Move the object so the center is correct.
  • Select object, select empty, parent (ctrl+p).
  • Now, you need to move the empty to compensate for the new center. That means moving it on the Y-axis. You can grab the curve in the IPO window, or you can move each keyframe in the 3D view, then overwrite the keyframe with I.

A bit of a bother, but shape keys are a bit old-school in that they cut you off from a lot of other editing possibilities. I’d love for some masochistic dev to make them more flexible.