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doCHtor
04-17-2009, 08:39 AM
I got to a point where TCB controller for rotations on a few objects (pelvis/chest) seems to bee the only way to go. I can live with how they are controled, but still I would like to have some visual reprezentation in forms of curves.

Only thing i come up with so far is to make a script which would create a dummy object with xyz controller for the rotation and than align and key it in every keyframe to match the position of my object with tcb controllers. Than using some kind of callback, every time my tcb object would be transformed, i would have to re-key the xyz object (probably only from the previous to next key of the tcb object).

Before I get to coding (which i suck in :rolleyes: ), i would like to hear what you think, if there is a better way to do it, if it's ok performance wise or if it's doable at all.

Thanks for any comments.

eek
04-17-2009, 02:46 PM
I would say if this is for gimbal reasons, how will you fix the gimbal coming from an euler>TCB direction, rather than the other way?

Pixar did something a while back, which would in the viewport use a direction and a spin, essentially a pole vector with an up node, and display euler rotation keys in the graph editor.

The present invention includes a method and apparatus for representing joint rotations of character models that eliminates the artifacts imposed by the ambiguities inherent in four angle rotations. An embodiment of the invention transforms joint angles from their original four angle representations into a set of defrobulated angles that provides the least confusion between position and twist information. Manipulating the character model using the set of defrobulated angles eliminates the angular discontinuities responsible visual “popping” and other visual discontinuities. In an embodiment, an animator specifies a pose using joint angles in their four angle Euler form. The joint angles of the pose is transformed to the defrobulated form. The defrobulated joint angles are weighted and applied to the points of the character model. The weighted sum of the defrobulated angles for each point are then converted back to an Euler angle form to pose the point.

doCHtor
04-17-2009, 02:56 PM
Yes it's for gimbal reasons. I'm aware that at the moments when gimbal would happen the curves on the helper object will be doing funny things, but hopefully most of the time they will be ok... or no? :curious:

It would be cool to have that pixar stuff, but i'm afraid someone will have to make a plugin for max :scream:

eek
04-17-2009, 08:54 PM
Yes it's for gimbal reasons. I'm aware that at the moments when gimbal would happen the curves on the helper object will be doing funny things, but hopefully most of the time they will be ok... or no? :curious:

It would be cool to have that pixar stuff, but i'm afraid someone will have to make a plugin for max :scream:

One will imitate the other in either direction. I.e you get gimbal using the euler curves in the graph editor your'll get them in the viewport with TCB. I think this would still happen with the pixar method - the difference is you can visualize the gimbal much better there way in the viewport, and so when you get to the curve editor your starting from a good set of keys.

doCHtor
04-17-2009, 09:22 PM
I'm not sure I made myself clear. I want to use only TCB for animation, tweaking everything using only TCB parameters. XYZ on the helper object would be only to check the curves in curve editor to see acceleration and so on. I don't want to edit the curves from curve editor.

eek
04-18-2009, 02:51 PM
I'm not sure I made myself clear. I want to use only TCB for animation, tweaking everything using only TCB parameters. XYZ on the helper object would be only to check the curves in curve editor to see acceleration and so on. I don't want to edit the curves from curve editor.

Ah ok, cool.

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