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Slurry
07-26-2006, 04:09 PM
Hi Folks,

I have yet another constraint/props question.

Here is the scenario: My character is holding a prop (think something long and narrow like a club, sword or baseball bat) in his right hand. I have rotation constraints set up so his hand rotation matches the position and rotation of the prop obect which gets its motion from optical data. This keeps the prop handle from sliding and jittering inside the character's hands and the motion capture looking natural.
Everything works like a charm until the real life actor decides to spin the prop loosely in his hands.
Now my rotation constraints that link the hand movement with the prop are causing the 3D character's hands to rotate about themselves too far.

I need the prop to be able to spin about itself while the character's hands match the prop but don't twist around and around when the actor spins the prop 180, 360, 720 degrees.

Any ideas for a constraint hierarchy that can handle this?

Art

ps - I hope that description is clear! ;)

donShole
07-26-2006, 04:15 PM
Not sure about your description, but maybe using a handle (if you're using mb 6+) could help?

softdistortion
07-30-2006, 04:14 AM
If you are using optical data I'm assuming you use MBPro? I'd go in and try cut out the spin parts on the optical to clean that up and interpolate from nonspin to nonspin sections.

Slurry
08-01-2006, 03:11 PM
Thanks for the replies guys. It doesn't look like there is a "good way" to get the results I want. I need to plot to skeleton, delete unwanted frames and reapply constraints and keyframes to fudge it. The handle suggestion works well for adding/fixing motion to the hands and prop though. Thanks for that tip!

Art

softdistortion
08-02-2006, 02:48 PM
Just for my own curiousity...any feedback on why it wouldn't work to cut out the bad sections in fcurves and iterpolate like you would with occluded marker clean up? Sound like you are kind of doing that but sounds more time consuming?

Slurry
08-03-2006, 06:21 PM
I want to keep the spinning parts from the optical data, but once the hand is contrained to the prop, the hand spins (twists too).
It's the constraint that is causing the over rotation of the hands, not the data or keys of the hand itself.
So, plotting to the skeleton and deleting the bad sectors in fcurves is just what I did. I'm not sure exactly what you mean by interpolating occluded data...I know that is a process when working with optical data but I am working with a plotted control rig at this point.
I think I just don't understand fully what your technique entails.

Art :)

softdistortion
08-04-2006, 12:42 PM
gottcha..thanks for detailing that. :)

oakentree
03-23-2007, 05:41 PM
I have a related problem in 3ds max - I need to make my prop bone to be locked to the hand bone of my biped skeleton so that it will rotate naturally as if the prop was being held by the hand. Could anyone who knows how to do this guide me more or less step by step since I'm rather inexpert with 3ds max?

donShole
03-25-2007, 02:56 PM
I have a related problem in 3ds max - I need to make my prop bone to be locked to the hand bone of my biped skeleton so that it will rotate naturally as if the prop was being held by the hand. Could anyone who knows how to do this guide me more or less step by step since I'm rather inexpert with 3ds max?

You really should ask this in a 3ds max forum.

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