View Full Version : rotate about another objects pivot

04 April 2006, 09:10 PM
hey everyone,
i'm trying to come up with a resolution for a way to rotate an object using another objects pivot. it would be easy to just reset the pivot of the object to snap to the other object, but i'm dealing with referenced characters, and i'm trying to avoid messing with a referenced pivot if i can help it, it just sounds messy. specifically im trying to get a characters foot control to rotate about his knee, like he's kneeling and he rotates his body. the knee should stay the pivot but the foot should rotate relative to the knee's pivot.

does anyone have any good solutions for such a thing? i'm having a hard time getting this to successfully happen with mel (trying to create a locator and constrain it... that works, but being able to manipulate the rotation doesn't work too well).

thanks for any tips...

04 April 2006, 02:53 PM
If I'm reading you right...which I might not be: When I rig my characters, to achieve that, I use an IK handle attached to the top of the leg, down to the foot, (with the knee in between) and have theknee joint Pole Vector constrained to a Locator just infront of it.

If that sounds like it might work for you, I can give you a more detailed explanation if you need it.

04 April 2006, 04:59 PM
hey ham,
thanks for the reply... i've got my pole vector already set... but this is more like the rotation of the foot. i drew a pretty picture to help illustrate my point. blue is the control of the foot, red is the pivot. in the left picture, that's where the rotate is by default (makes sense). on the right is where i'd like the script to rotate about.

04 April 2006, 05:05 PM
Perhaps create a second manipulator, which the foot is parented to, that has its rotate pivot at the knee? That way you can choose how you want the foot to rotate by selecting the 2 different manipulators...

04 April 2006, 05:45 AM

do you looking for a solution like the auxilliary pivots? If i understand you right what you trying to achieve is a blend between fk and ik. Are you scripting a new auto-setup-tool? I dont know a lot about Matices and how to do Mathematics whith them. If you feel comfortable with Matrices you will be right on Track. :-/

Have no Idea but your Question really make my stupid Brain running. :)

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04 April 2006, 05:45 AM
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