How do I add a child to the tail modular control rig so that it becomes the parent to the next control?

Development Character & Animation
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1

I am trying to create a Modular tail control rig that will add a null value underneath the control so that it becomes the parent to the next Control. Unfortunately, while I have had some success in making the null, I find myself unsure how to make it the parent. I have had some success in modifying the StandardFunctionLibrary to create a child null, but I need to figure out how to make it the parent to the next rig_fk_ctrl.

Concept:

tail_01_rig_fk_ctrl

-tail_02_rig_fk_ctrl

--tail_03_rig_fk_ctrl

etc

becomes

tail_01_rig_fk_ctrl

-tail_01_rig_null

--tail_02_rig_fk_ctrl

---tail_02_rig_null

----tail_03_rig_fk_ctrl

-----tail_03_rig_null

etc

Alternatively, the purpose of this is so that I can create an inverse scale for the control’s direct child, so when it gets scaled, the null under it can get the inverse of the scale. I don’t mind if I can do this to the default null that comes with the modular tail control, but I don’t know how to plug in the value to a child (or get the null to access the scale of its parent)

concept:

tail_01_rig_fk_null (no scale modification)

-tail_01_rig_fk_ctrl

--tail_02_rig_fk_null (inverted scale of tail_01_rig_fk_ctrl)

---tail_02_rig_fk_ctrl

----tail_03_rig_fk_null (inverted scale of tail_02_rig_fk_ctrl)

-----tail_03_rig_fk_ctrl

etc

2

Steps to Reproduce
N/A

3

Hey Peter - I don’t quite follow. Can you use the SpawnControl and SpawnNull nodes in order to first create the control - and then create the null with the Control as the parent? I must be missing something here.

Thanks!

Best,

Helge

4

Hey Peter - apologies for the late reply. You can use the SpawnControl and SpawnNull nodes - and feed the result as a parent into the next one. To access the parent transform you can just use GetParent and GetTransform on that. for inverse scale you could access the parent’s scale - invert it and then set it as as the local scale on the null.

There are so many options here - and so many ways of how to achieve this. Attached are two images showing how to create a hierarchy with nulls as children. The inverse scale would have to be computed during the forward solve.

I hope this helps,

Best,

Helge

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5

In Unreal, I am trying to modify the Tail Module. The tail module creates controls that are parented to the previous and become the parent to the next. There is an option to add a null above the control that becomes parent to the current control. What I want to do is add a null underneath the current control, and the next control becomes the child of the new null.

In my example, I have the fk_null and the fk_ctrl from the original Tail Module. My custom nulls are the subNulls. I want to make it so the fk_ctrl or the fk_null (depending on whether I have the fk_null option on) is the child of the previous subnull null (so in my second example, the tail_03_rig_fk_ctrl would become the child of peter_test_subNull of the tail_02_rig_fk_ctrl [Image Removed]

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