Hi, I'm having a look at the following all related issues : https://trac.osgeo.org/postgis/ticket/1940 https://trac.osgeo.org/proj/ticket/185 https://trac.osgeo.org/gdal/ticket/4762
related to EPSG:2065 support, ie "S-JTSK (Ferro) / Krovak". There's an issue about the datum shift used, but that's an easy one compared to a more serious one regarding axis order. The proj.4 krovak method expects the first value of a coordinate pair to be a easting, and the second value a northing. Whereas original Krovak (EPSG:2065) is supposed to be southing first, westing second. https://trac.osgeo.org/gdal/ticket/4762 suggests to add a "+to_meter=-1" parameter. Which means that the coordinates supplied are first westing, second southing (instead of "+to_meter=-1", a cleaner equivalent way is to use "+axis=wsu", meaning westing,southing,up ) But EPSG would mandate southing,westing. But admitedly, for less exotic coordinate systems with official EPSG axis order latitude,longitude (EPSG:4326...) or northing,easting (some Finland projected CRS for example) we have never introduced in GDAL WKT or proj.4 strings the +axis option, and the application/user does the coordinate switch itself before passing that to GDAL/proj. So, does that sound OK that a user providing coordinates advertized to be in EPSG:2065 does that in westing, southing order ? Or was this something particular to this user ? (I'd note that the dataset mentionned in the ticket is a GML resulting from a WFS server, and we all know the axis ordering issues related to WFS) What a mess... (Using EPSG:5221 which is the easting, northing variant avoids those headaches) Even -- Spatialys - Geospatial professional services http://www.spatialys.com _______________________________________________ gdal-dev mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/gdal-dev
