I was debugging rotation between two poses yesterday and realized that if you rotate 180 degrees around x axis, and then rotate around the z axis between 0 - 180, the z angle for axis-angle relative rotation will stay zero, while the x and y angle will fluctuate. This shows again how tricky rotation is, and especially how hard it is to properly extrapolate/partition the rotation space.
Here, I used claude to help visualize the change of quat/axis angle while we rotate the poses using euler.
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