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Spherical Earth vs. Spheroidal Earth #2

Closed GoogleCodeExporter closed 9 years ago

GoogleCodeExporter commented 9 years ago 
This code assumes the earth is a sphere.

Google Earth uses a Spheroid model (used by GPS) to account for the
flattening of Earth near the poles.

If the radius of your circle is < 10,000,000 meters you probably won't
notice.  The error is normally only a few hundred meters.

That said we could still use the Spheroid model.  It's a bit more
complicated since it's not "rotate a point around vector" anymore.

Original issue reported on code.google.com by nickgsup...@gmail.com on 11 Sep 2007 at 4:34

GoogleCodeExporter commented 9 years ago 
My VB.NET version includes some code to allow for the "oblate spheroid" shape 
of the
Earth. It isn't exactly the same as WGS-84, which includes some perturbations 
to the
spheroid, but near enough, I think.

Original comment by frank.jo...@gmail.com on 4 Apr 2009 at 3:24