Best way to keep pivot alignment after freeze transformations

Best way to keep pivot alignment after freeze transformations

Anonymous
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Best way to keep pivot alignment after freeze transformations

Anonymous
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I have a planet and a rocketship. All history as been deleted and all transformations have been frozen to 0:

overview.JPG

 

Goal: To blast the rocketship off into space by altering only its translate Z attribute. I also want to be able to check if the rocketship is grounded on the planet by checking its Z attribute is 0.

  1. Select Rocket mesh

  2. Press D and rotate its pivot around so the blue Z arrow is aligned with the nose cone of the rocket

  3. Bake the pivot

Unfortunately this doesn't work because upon baking the pivot we get this:

Bake.JPG

Look at the translate x, translate y and translate z attributes! They suddently are not zeroes anymore! (as a bonus I would be interested in knowing where these values are dervived from).

A beginner would immediately think applying freeze transform after editing the pivot would turn everything back to zero. And while it does, it also resets my edited pivot:

transform.JPG

 

Thanks to help from Maya's reddit the steps to achieve what I want are:

  1. Select Rocket Mesh

  2. Press ctrl + g to child the Rocket mesh to a parent group

  3. With the parent group selected, center pivot on the group so its pivot is aligned with the Rocket Mesh

  4. Press e to rotate the group itself (NOT just its pivot) so that its blue z arrow is aligned with the direction you want the Rocket Mesh to travel

  5. This will rotate the Rocket Mesh as well because it's a child of the parent group. So realign the Rocket Mesh so the nose cone of the rocket is aligned with its parent group's blue z arrow.

And that's pretty much it! I can now drag the blue arrow of the parent group and the rocket blasts off and lands, moving only in the X dimension:

blastOffJPG.JPG

 

Questions:

  1. Is the best way to do it? It seems sort of hacky? My steps might be wrong feel free to correct them!

  2. Why does the translate Z attribute also change as I change X? I certainly did not set up such a relationship! Look at the above image! Translate X is -1.598 which I dragged it to, but translate Z is -1.571? Why? Because my rocket is at an angle (in world space) it is moving in two dimensions which somewhat explains it, but doesn't an object's transform attributes show local space? Especially after a freeze? It's making me uneasy. You can see Z change on its own accord more easily in this video:

https://streamable.com/ghiet

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jmreinhart
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No, that solution is fine.

In general if you are animating a model you would want it to have a rig (a set of controls that the animator uses to manipulate the model instead of directly manipulating the model).

For this scene, having a rig isn't "necessary".

Pivots can seem very convenient at first but having the 0,0,0 point of the object be the pivot is more robust (which is important for real rigs).

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