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Groovedog
09-11-2005, 06:27 AM
Hi all,

Looking for someone to tell me what I am doing wrong here. I have created a head model with seperate mesh for the eyebrow. I am trying to create a "link with" relationship between translation in POSX of a implicit circle to rotation of the eyebrow in POSY.

I get the relationship setup and when I move the controller the eyebrow swings out and away from the head.
I have the eyebrow parented to the main head bone. I understand that the eyebrow's center is now the main head bones (Parents) center which is why it's swinging out.
I've been going through the manual on freezing transofrmations and neutral poses and pivots.
It's swinging out and away because it's center is on the main head bone. the solution would be to get the center to stay at the center of the eyebrow bounding box but I can't figure out how to get it to do that.
I'm a newbie learning on my own and I appreciate any suggestions.
I searched the forums and found discussions on center and freezing transforms but nothing specific. I'm sure it's something I don't understand about center, neutral poses and pivots.
zukezuko
09-11-2005, 11:10 AM
Just place the center manualy or by selecting vertices and Transform>move center to vertices.
Maybe you did something wrong with the linking.
Well other than parent you could use a constrain, Have a null parent to head bone
at the position of the eyelid, and position constrain the eyelid to it.
mattmos
09-11-2005, 12:25 PM
Probably the easiest way to do this would be to parent a null to the headbone where you want the centre of the eyebrow to be and parent the eyebrow to the null. That way you zero out the transforms and your link withs/expressions are local to the null.

If the centre of the eyebrow object has moved away from the mesh, simply select the object and choose 'move centre to vertices' from the right side transform menu.
Groovedog
09-11-2005, 05:49 PM
Thanks Matt and Zuke,

I should have known! After watching Adam's tutorials on rigging, the null is a solution for alot of things in XSI it seems.
So if I center the Null to the eyebrow then parent the brow to the null and the null to the head bone it should work.
I will give this a shot. I appreciate the help!
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09-11-2005, 05:49 PM
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