how to link group's pivot to a dummy's pivot?

[eodeo]

I need to animate CAT character growing as it walks. I was thinking that it would be easiest if I change the scale of the world around him rather than changing CAT object scale.

Changing CAT object scale directly, corrupts mesh. Adding xform on top of physique(skin) glides the character the more it moved relative to its start point, so it too is no good.

I grouped everything in a group called world. I would like to link world to the dummy that guides CAT walk along a spline.

In short, how to link group's scale pivot to a dummy's pivot? Regular link info would do the trick if it included "inherit" dialog it has with non group object selected. I need all objects to shrink/grow relative to each other about a select dummy pivot.

I hope that's clear enough. Thank you!

[CAMedeck]

Instead of grouping the objects (which is never a good idea) can you just link them all individually to the dummy object?

[eodeo]

Thank you for your answer!

I have to group them, unless there is another way to make all objects change scale relative to each other- which is the whole point of my original question.

I need all objects to change size relative to each other, while the pivot is centered on a moving dummy.

[Brock_Lafond]

I would create 2 dummies, of different size and align them to each other.

Link your objects to dummy 1.

Position constrain dummy 1 to dummy 2.

Use wire parameters to drive the scaling. Wire the XYZ scale of dummy 2 to the objects.

Scale dummy 2 to scale the objects. Move dummy 2 to move them as a collective.

[eodeo]

Thank you for your suggestion, but either I did it wrong, or it's not working.

Using wire parameters, I linked dummy's scale to group's scale. While it is scaling, it does not use dummy's pivot.

p.s. i already have 2 dummy's, so I may have been confused. Dummy1 controls CATs motion on a path. Dummy 2 is linked to dummy 1 so that it has correct position in the world. I scale using dummy 2, to avoid scaling CAT itself via dummy1. Maybe I need dummy 3?

[Brock_Lafond]

If everything is rigged and skinned properly the simple solution is to link constrain the animation rig to a master node and then scale the master node.

If the hierarchy is correct everything will scale uniformly including the bones. This in turn will scale the mesh uniformly and shouldn't cause loss of mesh integrity.

Just don't link skinned objects.

[eodeo]

Thank you Brock_Lafond. I tried to link both the CAT parent and all the bones to a separate dummy which I then scaled. Linking CAT parent and scaling the dummy did nothing, while linking the bones made them all move in space to the dummy's pivot and made any changes useless.

As I've already noted, changing CAT units ratio on the CAT parent corrupts the physiqued (skinned) mesh. However, it does change the size of bones properly, but ultimately it's not the bones I want to change in size, but the mesh that they're driving.

[eodeo]

Solved! I used linked xform above the physique modifier and chose a separate, static dummy centered on the dummy that is driving the CAT's motion along the spline.

So while I couldn't change the world, I did change the character mesh- which was the whole point of changing the world's scale. I just thought that it would be easier.

Thanks for all the help!

[eodeo]

My solution wasnt perfect. In fact it was far from good, but I think it will work. Still my original problem and how to solve it remains.