Animation: Copy Translation from one Object to another

Ribanok

I have a Cube, for which I created some keyframes in the timeline. It translates and also rotates.

Now I have a second object, e.g. a cone, which should follow the first object. But the cone should only do the translation, not the rotation!
(In the end I plan to have a camera or a Light moving along with the animated object. But the dircection of the camera shall be fixed.)

Unfortunately I found no way to achieve this:
- Simply setting the cube as parent for the cone in the scene will also bring rotation to the cone.
- In the timeline I can see the relevant keyframes for the cube under Properties/General/Transforms/Translations. But I have not found out, how to copy-paste these for the cone.

 

In the attached pictures you can see, what I want to do. But I created the pictures by adding movement to the cone completely manually, the cone was not attached to the cube.

margrave

A) Parent both objects to an empty.

B) Use an ERC to copy the translation properties.

Ribanok

margrave said:

A) Parent both objects to an empty.

B) Use an ERC to copy the translation properties.

These are two different approaches, right? (Or two steps für single solution?)

I am not good with ERCs, but I guess with B) you mean: Create an ERC for the cone and its inputs are the x/y/z-coordinates of the cube. Only the cube has keyframes in the timeline, not the cone and not the ERC. Is that basically right?

Richard Haseltine

Save a pose preset and use the options dialogue to include only the properties you want, or save a regular preset and hold down cmd(Mac)/ctrl(Win) when you double-click to get a dialogue that lets you limit what it affects.

margrave

Ribanok said:

margrave said:

A) Parent both objects to an empty.

B) Use an ERC to copy the translation properties.

These are two different approaches, right? (Or two steps für single solution?)

I am not good with ERCs, but I guess with B) you mean: Create an ERC for the cone and its inputs are the x/y/z-coordinates of the cube. Only the cube has keyframes in the timeline, not the cone and not the ERC. Is that basically right?

Those are two different options.

Regarding B, every property can have a sub-component (another property that is changed by it) and a controller (what properties affect this one). You set these relationships in the Property Hierarchy pane.

Ribanok

The suggested solution from Richard works perfectly.

There was also a third dummy object necessary, because after applying the previously saved pose preset, this object has the very same position as the first object. But the save-to-pose-preset is indeed a very nice way, to extract only translation and not rotation. Thank you very much!!

 

Okay, if possible I would now also like to learn better this ERC thing, margrave has mentioned.

I guess, then the translation of the first object (cube) would always automatically be used by the second object (cone). I mean, if the position of the cube changes, then the position of the cone follows on the fly. (?)

Do I have to create a NEW property? Or just use existing properties of the cone and specify there the cube translation as input?

If I need a new property, does it mean, that I must create a new slider, which is always set to 100%?

I tried to do this (create a new slider "follow" for the cone) and then clicked on ERC freeze in the parameters pane. Under Controllers I want to read the translation of the cube, propably 3 entries, for x, y and z.

But I am not sure, how to do that. When I try to get the x value of the cube, why is there under Propery already a ZTranslate entry present? Of course, initially I had moved the cube a little out of the way on the z axis, but why is this visible under its Property XTranslate?

margrave

In theory, all you need to do is click the boxed P next to the property and drag it to the Property Hierachy, under the Controller header for the property you want it to control. You shouldn't need to create a separate slider.

I'm not sure which type to set it to. I mainly use ERC for adjusting the position of accessories when posing, so ERCKeyed/Linear is all I'm familiar with. I think you want either ERCAdd or ERCDeltaAdd.

Ribanok

margrave said:

In theory, all you need to do is click the boxed P next to the property and drag it to the Property Hierachy, under the Controller header for the property you want it to control. You shouldn't need to create a separate slider.

I'm not sure which type to set it to. I mainly use ERC for adjusting the position of accessories when posing, so ERCKeyed/Linear is all I'm familiar with. I think you want either ERCAdd or ERCDeltaAdd.

 

Thanks for your help, it worked!!!

What you originally mentioned as "Parent both objects to an empty." was also necessary, because without it was not possible to make a connection between the two objects.

But then it worked exactly as you suggested: I simply dragged the 3 Translation properties from the cube into the Property Hierarchy under the cone, for example "X Translate" from the cube under XTranslate / Controllers / 1st stage. There has been automatically generated an entry "ERC[DeltaAdd] : XTranslate (X Translate)" with cube as source.

Your advice was more helpful to me than any of the official documentation for ERC I have found so far.

margrave

Yes, I'm more familiar with the Blender equivalent, Drivers, which let you change properties from anywhere in the scene. I forgot you need a parent-child relationship to set controllers in Daz.