Convert Rotation Quaternion to Polar Coordinates?

Hi Everyone,

Would anyone happen to know how to convert rotation quaternion to polar coordinates?
On my noob understanding, this is what is needed for the arc rotate camera (primarily alpha and beta) to work.
Currently all of my mesh uses rotation quaternion and I tried to used toEulerAngles() but it didn’t work as I expected.

Any help is greatly appreciated! :smiley: