I am trying to create a graphic demonstrating the difference between an idealized perfect sphere and the Earth's reference ellipsoid. (I know this is also an approximation, but nevertheless.) To this end I want to also exaggerate the eccentricity of the ellipsoid.


Anyway, should I simply scale a sphere vertically such that the vertical axis is shorter than the horizontal axis? If I have a map of the Earth wrapped around the sphere, is squashing the sphere vertically sufficient? Or do I need to convert between geocentric and geodetic latitude first?

What's the proper way to handle this situation?

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    See also quora.com/… – Kirk Kuykendall Jul 19 '18 at 3:13
  • If your purpose is simply to create visuals to demonstrate the shape of the Earth I wouldn't worry too much about all this; just scale you Earth and its texture vertically and the result should be good for your needs I believe. – FSimardGIS Jul 23 '18 at 4:02
  • Well, I am trying to demonstrate geodetic latitude. I have already created a texture for the graticule based on geodetic latitude. I now need to know what I should do with the texture lying underneath the graticule, of the continents, oceans, etc. I could simply squash it vertically, as I have described. Or I could UV map it using a method intended for spheres, but not ellipsoids. Or I could... do something else? – posfan12 Jul 23 '18 at 22:40
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    Possible duplicate of Oblate ellipsoids and latitude – posfan12 Jul 23 '18 at 22:44