[OSM-dev] Mapnik projection slightly wrong?

[Jan-Benedict Glaw]

Hi!

I just looked at applications/rendering/mapnik/generate_{image,tiles}.py
and noticed the projection string:

	+proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0
	+y_0=0 +k=1.0 +units=m +nadgrids=@null +no_defs +over

`a' and `b' are ment to be the equatorial and polar radius of the
earth. Since we all use GPS, I guess we want to use the WGS84
ellipsoid, where the polar radius (b) would be 6356752.315m, instead
of 6378137.000m?  Is this intentional?  At least, osm2pgsql uses the
same, so all of the users are identical :)

MfG, JBG

-- 
      Jan-Benedict Glaw      jbglaw at lug-owl.de              +49-172-7608481
Signature of:  The course of history shows that as a government grows, liberty
the second  : decreases."  (Thomas Jefferson)
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