In this commit, a new way to set the bone roll is introduced. It aligns the z-axis of the selected bone(s) to the 3D-Cursor, so that the cursor intersects with the YZ plane.
This makes it easier to align bone rolls to a target, for use in rigs where arms/legs are not horizontal/vertical. To use this, just press Ctrl N, and choose the "Align Z-Axis to 3D-Cursor" option.
Credits go to Robert Christian (wavez) for providing the method as a working BPy script, that demonstrated this in action.
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