Scaling Avatars and Setting Bone Positions

[awstorer]

Hello there!

I am trying to set the absolute position of individual bones in my avatar, but am getting mysterious results depending on whether I've scaled the avatar first.

I determine the parameter sc to be the degree of scaling, and then apply:


mySubject = viz.add('./resources/object/vcc_male.cfg')
mySubject.setScale([sc,sc,sc])

The problems occur when I set the position of a specific bone.

armForeBone = mySubject.getBone('Bip01 R Forearm')
armForeBone.lock()
...
armForeBone.setPosition([10,20,10],viz.ABS_GLOBAL)
print "[10,20,10] Arm Position:",armForeBone.getPosition(viz.ABS_GLOBAL)
armForeBone.setPosition([0,0,0],viz.ABS_GLOBAL)
print "[0,0,0] Arm Position:",armForeBone.getPosition(viz.ABS_GLOBAL)

My hunch is that because I am retrieving the position in global coordinates, and then setting it in global coordinates, I should print out the following:

[10,20,10] Arm Position: [10,20,10]
[0,0,0] Arm Position: [0,0,0]

Prior to scaling, I get the following:

[10,20,10] Arm Position: [10.0, 20.000001907348633, 10.000000953674316]
[0,0,0] Arm Position: [1.4901161193847656e-008, -1.1920928955078125e-007, 7.4505805969238281e-009]

While I'm a little mystified as to why there is a rounding error, it really doesn't make much difference to me. What is troubling is that after I scale, I get the following:

[10,20,10] Arm Position: [7.8901848793029785, 15.965287208557129, 7.8532319068908691]
[0,0,0] Arm Position: [0.031053377315402031, 0.24702535569667816, -0.0058987573720514774]

This is not the position I set! How can I set an exact position after applying a scaling?

Thanks very much for any assistance, and I hope I've provided enough information! :)

~Alex