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View Full Version : Rotation pivot help!



walfridson
11-26-2005, 10:22 AM
http://walen.se/rot.jpg
http://hem.spray.se/johan.walfridson/rotate.gif
I want to use a Null for another objects rotation pivot. Being able to move the null independently from the object and still use it as the pivot.
I'm no expression wiz so help me out :)

Dodgy
11-26-2005, 12:01 PM
Ahhh, sorry, misunderstood! I'll have to think about that one!

jeremyhardin
11-26-2005, 12:38 PM
why would you need expressions? parent the object to the null. rotate the null to rotate the object.
then just use the object's own movement channels to move it independently. as long as the null doesn't move, you'll have what you're describing above.

walfridson
11-26-2005, 01:15 PM
why would you need expressions? parent the object to the null. rotate the null to rotate the object.
then just use the object's own movement channels to move it independently. as long as the null doesn't move, you'll have what you're describing above.
I want to move the null.

toby
11-26-2005, 01:49 PM
It depends on what you want to do, but you could have the object parented to a series of nulls, each one placed where you want, and the rotation of any of them would rotate the object around it. Obviously there's no easy way to animate the pivot point, if you tell us what this is for we might be able to suggest another way -

walfridson
11-26-2005, 02:08 PM
Well, I have a rigged character. Nice feature to have a moveble rotate point. Like if he's spinning on one foot. No biggie but would be cool with a solution :)

toby
11-26-2005, 02:40 PM
That could certainly be done with a series of nulls. That's actually one of the things that nulls were created for! It was back in '98 that I heard the example of a railcar ( think Indiana Jones ) pivoting on one side and the other as it followed a sharp S curve, to demonstrate the purpose of nulls.

walfridson
11-26-2005, 03:43 PM
Got somewhat of a solution bit not optimal... :devil:
http://hem.spray.se/johan.walfridson/rotate2.gif

jeremyhardin
11-27-2005, 01:06 PM
looks like you already came up with a solution, but i was going to suggest parenting the box to one null, then add another null and apply channel follower to the box on the x, y, and z, positions. so the box's position is following the parent's rotation and the second null's position.