View Full Version : Help Please-Animated bone scale Max/Maya

02 February 2006, 11:59 PM
I'm trying to develop a method for animating a character who grows as he walks. He changes proportions-joints are farther apart at the end of the animation than at the beginning. And I would like some advice from experienced riggers or animators on how I should approach this.

This is a project for experimental graphics at my art institute. I have discussed methods for achieving this effect with my teacher and classmates. It has been suggested to me that I use a 2D morph to achieve the effect, such as Elastic Reality, or else a simple cross-fade. I rejected this suggestion out of hand because the final look is not as important to me as the method used. I want to learn to scale characters who have skeletal animation.

I have floated a few ideas for how this effect could be achieved. I figure that if I cant find any better way to do it, I can use morph targets (blend shapes) to transition between two or more meshes animated with seperate bones systems. However, I consider this to be an extremely poor solution. I believe that the positions of the bone joints themselves ought to be animatable. Though I expect to combine the change in bone proportions with a morph (blend shape) to change the appearance of the features.

I believe that this can be done, partly because I remember seeing a video, which I think was a technical video from a SIGGRAPH 1999 or earlier, which demonstrated this capability in a product.

I work primarily in 3DS Max. I have been using it continuously since version 2.5. I have done some preliminary tests in Max and have determined that scaling standard bones is not the answer. I suspected that this capability was available in Character studio (biped) but my testing has not yet revealed a method.

I am a raw beginner in Maya. But I find it similar enough now that I've got the basics of polygon editing and blend shapes that I believe I could pull off a project in it, but if anyone has suggestions for how this could be done I would need more detailed direction than I would need for any method suggested in Max.

Any observations about this project are welcome. I will, of course, continue to ask people and search for a method to do this on my own.

02 February 2006, 12:41 AM
Thanks to Steve B's post in a thread asking about facial animation I thought to try the skin wrap modifier in Max and use standard objects as bones. I've just performed a quick test and am extremely happy with the results.

I would still be open to finding a more elegant solution if there is one, and I may find difficulties once I get this project into production, but for now I think I might have my method.

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02 February 2006, 12:41 AM
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