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Object1 is a child of Object2. I rotated Object2 thus rotating Object1. In the Transform section of the N panel Rotation values of Object1 are 0,0,0. How do I get global values of rotation of Object1 related to world?

This may seem trivial when you have only 2 objects, but actually I have a chain of child-parent relations, each one rotated by some degree. Calculating this by hand would take ages.

I need to align rotation of the object that is not part of this child-parent chain with the object that is.

child rotation

jubi
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  • Could you add an image that describes the situation with parented objects and the independent one you want to align? The transformation of a child to parent is stored in the child object's matrix_parent_inverse see: http://blender.stackexchange.com/questions/3763/parenting-messes-up-transforms-where-is-the-offset-stored/3765#3765 – stacker Mar 01 '15 at 12:23
  • I added the image, I'd prefer to avoid Python scripting if possible. – jubi Mar 01 '15 at 14:49

3 Answers3

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  1. Add a Copy Rotation constraint to the object you want to rotate. In constraint panel, set Target to that child object;
  2. After seeing it being aligned well, CtrlA > Visual Transform;
  3. Delete that constraint, since you don't need it anymore.

Edit:

If you just want to "know" the global rotation info, you can simply AltP > Clear and Keep Transformation, then you will see the visual rotation applied, which is the global rotation. After getting what you want, you can simply CtrlZ to undo.

Leon Cheung
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I found a dirty workaround, maybe someone will find a cleaner solution:

Select rotated child object that you would like to align to. Press Shift-Numpad 1 to align view to the object. Press Ctrl-Alt-Numpad 0 to align camera to view.

Now your camera's Transform Rotation data are equal to global rotation of your child object.

  • Select object you would like to align.
  • Shift select your camera.
  • Go to object tab.
  • Hover your mouse over rotation values, press right mouse button, select "Copy to selected".

Voila, your object has the desired global rotation values.

stacker
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jubi
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0

Object A - object you want to know transform and rotation of.

Object B - object in world origin with zero transform and rotate

  1. Parent B to A (keep transform)
  2. Look the properties of B
  3. Undo parenting

This works with objects in parenting or constrain links

Mike
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