[Gdal-dev] Projected vs Geographic Coordinate Systems
Simon Perkins
sy at perkins.net
Tue Mar 20 00:06:50 EDT 2007
Simon Perkins wrote:
> I haven't looked at the source code for a long time, but what does
> OpenEV do here? Do you convert geo-coordinates into some more
> isotropic coordinate system before rendering, or do you just deal with
> the funky anisotropy at all stages?
In a related question, if I have a vector layer in a geographic
coordinate system, does OGR provide some convenient way to compute the
relative scaling of degrees in the east-west and north-south directions?
I guess it comes down to some simple geometry (the size of latitude
degrees is uniform, the size of longitude degrees go like square of
cosine of latitude, I think) , but just wondered if there was some more
sophisticated procedure for what must be a common task.
Cheers,
Sy
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