[x3d-public] Zee to thee or Zee to me?

[Joe D Williams]

So, does a debate emerge?. HAnim Humanoid space is by default same as x3d default coordinate space. Basically the x3d Right hand rule where the default viewpoint is facing -Z and if you are on the stage, at 0 0 0 you are looking into the camera, gaze toward +Z. If you move from 0 0 0, the translation to the right is negative, left is positive, up is +Y, and back is -Z and forward+Z. That is also the default rotation for any transform Transform (Joint) of the Humanoid. 

OK, so that was all there was, of course special transformations and rotations of the X Y Z directions for special purposes, including HAnim. For years data has been collected for examples of human stature. Many of those measurements happened to be of deceased and others with most data taken in while the subject is at rest face up. Thus, much of that data used X Y as the ground plane and z as elevation from the floor. Since that is not the model pose we needed for prior to animation pose, the measurement coordinate system was just tilted up, and the model then naturally was facing +Z. This worked fine along with other uses technically, so all is good. 

Until mid-19nineties or so. A major toolmaker, producer and distributor of graphics products decide that right-handedness has had its day and it was time for the lefties to create their niche. So, as the GL is forming along its traditions, Dx emerges. For some undeclared Dx reasoning, now the Z axis is yawed pi rads to make a lefthanded coordinate system. Funny things can happen when you animate a lefty with righty code. Think of the situation where the model doesn't know its Zs have been swapped. How will the model know this has happened? Born a righty but implemented as a lefty. Success or ptsd in store for user?

There is a clear way to convert righty models to lefty models and a systematic way to convert animation codings between the setups, but does the HAnim standard need to recognize both systems. With the goal of accumulating motion and interaction libraries, does x3d HAinimHumanoid need a property that says lefties are allowed and accommodated? 

Anyway, is it worth thinking anything about this now? 
Any common ways of dealing with import of lefty animations into x3d righty system?

Thanks,
Joe

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