void calc_rot(xyz look, xyz me)
{
xyz look_proj = new xyz(look.x, 0, look.z);
look_proj = look_proj.normalize();
xyz me_proj = new xyz(me.x, 0, me.z);
me_proj = me_proj.normalize();
double rad = ut.GetAngleBetweenTwoNormalizedVectorsInRadians(look_proj, me_proj);
double deg = ut.RadianToDegree(rad);
xyz result = ut.RotateUnitVector(me.normalize(), deg, new xyz(0, 1, 0));
Console.WriteLine("{0}: {1} {2}", me, deg, result);
}