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it
Posts:
3
Registered:
10/15/08


ellipse on 3d earth
Posted:
Oct 15, 2008 1:22 PM


I need equations for an ellipse that is over the earth to generate lat,long points in Google Earth.
I have the semiMajor,semiMinor, orientation and center lat/long points.
The equations I tried previously, I believe is for a flat surface and are not generating the correct points.
Here are the equations I'm using:
An ellipse rotated from an angle phi from the origin has as equation:
x= h + a cos( t) cos(phi)  b sin(t) sin(phi) y = k + bsin(t)cose(phi)+ acos(t)sin(phi)
where (h,k) is the center, a and b the size of the major and minor axis and t varies from pi to pi.
Any help would be greatly appreciated.
Thanks



