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Jannis
11-07-2006, 10:33 AM
I am pleasently surprised that the new joints in Mocca 3 can be oriented by using the Object axis tool. This means that for the first time outside Cactus Dans tools you can make some complex riggs with Mocca. However, I don't realy understand the Align tool. What does it align to? The parent, the child, the world, or does it snap to some close value. I can see it aligns the Z axis of the joint to the direction of the child joint (or whatever axis it is set to) but it does not always seem to be doing that.

When I use it while rigging often it does not seem to work in a logical way. Here is an example,

When I take an arm chain outside the spine chain to align it (the reason being that the spine is not straight but I need straight rotations in the arm chain and the fingers), trying to align any of the joints does not work. They stay the same, not only the parent but all of them. When I use the object axis tool and change the parent the align works. But the whole thing is unpredictable, or there is a logic to it which at the moment is not clear to me.

Joint orientation seems to be on the most part prety good with Mocca 3 if you want to do a T-pose character but seems to be a little more messy when the character is not straight forward. I am sure I am missing the logic by which the system was created.

Anyone cares to illuminate the subject?
MJV
11-07-2006, 03:45 PM
Yes when align joint is active the z points at the next joint. The orientation of the other joints should be determined (I guess) by the pole vector, either the internal one or the one you assign. However, it is possible to disorient a joint off axis even in a 2D chain, so you have to be careful how you draw them up or rotate them afterwards. Also it's possible to have a chain that doesn't line up along a single axis, so that would impact joint alignment. You can also use preferred rotations which would again have yet another impact on the final orientation. Personally I find it all rather messy and unpredictable, the internal pole unreliable, and am disappointed at not having joint zeroing.
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11-07-2006, 03:45 PM
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