> Does this assume the earth is a sphere? Of course, speaking about Earth is just for the mental image. > Can you keep the elegance of this coordinate encodin

> Does this assume the earth is a sphere? Of course, speaking about Earth is just for the mental image. > Can you keep the elegance of this coordinate encoding with convenient transformation operations and define somewhere a mapping from the quaternarion encoding of position into a non-homogenous oblate spheroid encoding like WGS84 ...? I don't understand the question.