Thursday, 7 May 2015

qgis - Transform World data from EPSG:4326 to EPSG:3857


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]]



Answer



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.


No comments:

Post a Comment

arcpy - Changing output name when exporting data driven pages to JPG?

Is there a way to save the output JPG, changing the output file name to the page name, instead of page number? I mean changing the script fo...