Parent inverse

Support Basics & Interface
1

Hi, I’m a little bit confused about the “parent inverse” stuff:

  1. What does the “clear parent inverse” action do exactly in practice?
  2. Can I access the Shift-Ctrl-P “make parent without inverse” action from the menus?
  3. Has all this something to do with the Alt-O “clear origin” stuff?

Thanks a lot.

2

  1. It means that the Origin of the children will be reset to be the origin of the Parent.

  2. No

3)Yes. If you do a Normal Parent (Ctrl-P) and then undo it with Alt-P, then the children would each return to their individual origins. If you do a Ctrl-Shft-P and then Alt-P-Inverse they would all still have the origin of the parent.

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3

Thanks!!

4

Hi,
I tried that “Clear parent inverse” thing and couldn’t understant what is it’s purpose . each time it had a different effect on the Child object.
I searched for any kind of a clear explanation for it in this forum and outside but I found nothing.
could someone enlighten us all about this matrix mystery in a way we can all understand?

5

What ? You couldn’t understand my clear and concise english?

When you Add an Object the position in 3D-space it is added is stored in the OB:Data as the ‘Origin’. (for this example say we parent a cube[child] to a plane [parent[) If you use Ctrl-P then the origin of the Child will be retained. So when you terminate the parented relationship the Child can return to the original position of its Origin.

If you use Shft-Ctrl-P the Origin is reset to the Origin of the Parent, the Plane.

Now, when you “Clear Parent Inverse” you would expect the same thing to happen as happens with Shft-Ctrl-P, but it doesn’t; the child does move, but not to Object Center of the Parent as you would expect. The reason for this is that the child maintains it’s spatial arrangement with the parent because that is usually desireable (think of Duplis) but gives up it’s link to its own spacial data.

If you unparent everything, Ctrl-A on both objects then rotate the plane (will be parent again) 90.deg and then parent them again, you’ll see that the child maintains it’s spatial integrity. Alt-P and “Clear Parent Inverse” and the Child is now subject to the spatial data of the Parent.

I have no idea what Inverse Matrix means.

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6

thanks pal, I appreciative your efforts to explain that thing, but still something is missing… maybe my brain…
could you give me an example for a circumstance when this is helpful and maybe from that I’ll be able to understand it?

7

http://download.blender.org/documentation/htmlI/ch14s07.html

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8

o.k. I got the idea of the shift-ctrl-P thing, but am still in the dark about the “Clear Parent Inverse” action. all I can say is when applying it on a child, the child scales to the size of its parent, rotates in 90 degrees and moves to a random spot in the 3d space. hmmm interesting indeed!
thanks Fligh forbeing so patient…

9

Hehe… if you don’t think animation, and if you don’t think of more than 1 parent and 1 child it’s probably going to be impossible to understand. Here’s my last try:

http://blender.isoserv.com/uploads/PInverse.blend

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10

o.k. I got the idea of the shift-ctrl-P thing, but am still in the dark about the “Clear Parent Inverse” action. all I can say is when applying it on a child, the child scales to the size of its parent, rotates in 90 degrees and moves to a random spot in the 3d space.

Of course, you never know when that might come in handy :slight_smile:

11

o.k I think I’m on it. those are the things I understood (and correct me if I’m wrong):

  1. Fligh Rulz!
  2. applying “clear parent inverse” on a child means that the child will be positioned, rotated and scaled as if it’s parent became it’s origin. so if a child is positioned (2,0,0) and the parent is (4,0,0) after applying “clear parent inverse” the child will be (6,0,0), because it considers the parent to be his (0,0,0)
    3.?