getSurfaceNormalIntersectionWithZAxis
Computes a point which is the intersection of the surface normal with the z-axis.
Return
the intersection point if it's inside the ellipsoid, undefined otherwise
Parameters
the position. must be on the surface of the ellipsoid.
A buffer to subtract from the ellipsoid size when checking if the point is inside the ellipsoid. In earth case, with common earth datums, there is no need for this buffer since the intersection point is always (relatively) very close to the center. In WGS84 datum, intersection point is at max z = +-42841.31151331382 (0.673% of z-axis). Intersection point could be outside the ellipsoid if the ratio of MajorAxis / AxisOfRotation is bigger than the square root of 2 Default value - 0.0
The cartesian to which to copy the result, or undefined to create and return a new instance.