I have set of two 3d vectors lying on the same plane. I would like to calculate
angles betwen each of these pairs, but in the "full" angle range: from 0 to 360 degree.
Angle = atan2d(norm(cross(v1,v2)),dot(v1,v2));
give me always angle in the rang from 0 to 180 degree, even if the second vector lies
on the right side of the first one.
How could this be improved?