[Proj] Google Mercator Projection

[Frank Warmerdam]

Christopher Barker wrote:
> Hi,
> 
> Craig Bruce wrote:
>> I am having a problem converting coordinate values from WGS84 
>> Geographic to
>> the Mercator projection that Google Maps uses. 
> 
> There was a fair bit of talk about this at the FOSS4G conference, I only 
> caught bits of it. This may help:
> 
> http://crschmidt.net/blog/archives/238/understanding-googles-projection-slightly-anyway/ 
> 
> 
> There was talk of a new EPSG code for the google Mercator projection:
> 
> http://crschmidt.net/blog/archives/243/google-projection-900913/

Craig,

You should also read the final FAQ at:

   http://proj.maptools.org/faq.html

It talks about how to stop pj_transform() from doing a big shift to get
from Mercator spherical coordinates to WGS84 ellipical coordinates.

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
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