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I have tried different open source tools to transform a world data shapefile from EPSG:4326 to EPSG:3857 but I always have an error. I'm not sure, but is it because of Antarctica?

I have tried with GDAL and QGIS and both are unable to do it. Why is it so complicated and how to do it?

The .prj is:

GEOGCS["GCS_WGS_1984",DATUM["D_WGS_1984",SPHEROID["WGS_1984",6378137.0,298.257223563]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]]

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    Can you open the .prj file and copy the contents of the file into your question field. It may be that your data is whacked. (I would put this in the comment field, but stackexchange doesn't let me do that with low rep. stupid feature of this site)
    – David
    May 24, 2013 at 19:23
  • I copied it in the edit
    – Below the Radar
    May 24, 2013 at 19:28
  • ok, that's totally not the problem. Sorry :/
    – David
    May 24, 2013 at 19:37
  • What error are you seeing, and how are you going from 4326 to 3857? You have to treat WGS84 as a spheroid with no flattening (not an ellipsoid) to get the "correct" Mercator XY coordinates.
    – Mintx
    May 24, 2013 at 19:40
  • the file can be found here: thematicmapping.org/downloads/TM_WORLD_BORDERS-0.3.zip maybe you could try to transform it to 3857 or 900913
    – Below the Radar
    May 24, 2013 at 19:41

1 Answer 1

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The Google Mercator projection is usually bound for aereas between 85.0511° North and South.

If your data includes 90° North or South, the reprojection is mathematically not possible.

See also http://wiki.openstreetmap.org/wiki/Slippy_map_tilenames for all kinds of lat/lon to Google Mercator conversions.

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  • thats right, the data bounds are +-90 North and South. But why is not possible to transform it in Mercator if the North and South extends infinitely in this proj. see: radicalcartography.net/?projectionref
    – Below the Radar
    May 24, 2013 at 19:49
  • 3857 is not Google Mercator... its 900913
    – Below the Radar
    May 24, 2013 at 19:50
  • EPSG:3857 and OpenLayers:900913 are equivalent definitions that are describing the internal projected CRS used by Google Maps, Bing Maps, etc.
    – mkennedy
    May 24, 2013 at 19:58
  • Have you ever noticed in Google Maps that you can drag the map North and South indefinately?
    – Below the Radar
    May 24, 2013 at 20:22
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    Yes, but never reaching 90° North/South.
    – AndreJ
    Aug 1, 2013 at 16:58

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