Wrong pivot point of parent / wrong scale of children

Question

I'm trying to make two objects, in is an intact glass, the other one is the glass but shattered.

So for the shattered glass, in Maya I make a Plane, cut it with the multi-cut tool, extrude the faces, select the object and then separate. So I have every single piece of the glass as a single object. After that, I select them all, Modify->Center Pivot.

Now when I import this into unity, this is where the problems arrive.

• When I rotate the native parent object, which holds all the glass pieces, it looks right:

Native Parent Rotation

• When I rotate all the child glass pieces, the distort some weird way, the scaling is really off on one axis and they appear very thin:

Native Child Rotation

• Now, when I create a new empty GameObject on root level, and simply add all the children glass pieces to this object, they rotate just fine and have the right scaling:

New Parent - Child Rotation

• But now, when I rotate the parent, the pivot point seems to be completely off:

New Parent - Parent Rotation

The rotation I make is a simple gameObject.transform.Rotate (Vector3.left);

How can I achieve the correct pivot point for the parent, and avoid the weird scaling issues on the children? I need to be precise of course, because the shattered parent object is supposed to replace the intact glass object 1:1 after a collision.

Answer 1

Okay, I finally fixed it after several hours.

Problem was, my parent plane in Maya was set to something like 6,3 / 2,1 / 3,1. So this was the scaling the object always got imported into Unity, which messed up its space / pivot points.

In Maya I now just used Modify->Freeze Transformations on the Plane, to normalize it to 1 / 1 / 1. After that I had to re-reset my pivot points on my glass pieces (select all, Modify->Center Pivot.

Now all rotates around the correct pivot points and scales the way it's supposed to.