André, > > I am not sure I follow what this has to do with the projection name in > WKT. The newer WKT specification (ISO 19162) relies solely on the > identifier to determine which operation method to use to project > coordinates,
Do you know if there's a publicly available version of ISO 19162 ? I could only find this draft on OGC website: https://portal.opengeospatial.org/files/?artifact_id=54797 ( accessible from http://www.opengeospatial.org/standards/requests/112?utm_source=emailcampaign219&utm_medium=phpList&utm_content=HTMLemail&utm_campaign=The+OGC+requests+comment+on+the+candidate+standard+Geographic+Information+%E2%80%93+Well+Known+Text+for+coordinate+reference+systems ) > but the older WKT tends to follow OGC 01-009 which lists > explicit names to use for the projections. So regardless of what the > EPSG registry uses for a name, this is the name that is supposed to be > used for the OGC WKT as far as I am concerned: > OGC 01-009 (http://www.opengeospatial.org/standards/ct): "Mercator_1SP" AFAICS, OGC 01-009 is very light on details unfortunatelly (doesn't mention parameters of all projections), and things have more or less crystalized by the practice of the various vendors (including GDAL/libgeotiff/proj.4). But yes, it does mention "Mercator_1SP", and the geopackage spec mentions OGC 01-009 as the standard to use for WKT. > > I would ask if this is not a bug in the geopackage itself or whatever > created that WKT string. Not geopackage itself, but the NGA's profile on it. But your point on not mixing the old OGC 01-009 with ISO 19162 new practice is good, and should likely be submitted back to NGA. > I'm not opposed to mapping that "Mercator variant A" name to > SRS_PT_MERCATOR_1SP on WKT import, but I think there's a limit to how > far one should go to support non-standard WKT. In an ideal world, everyone would follow standards, and there would not be many standards/formats to do the same thing ;-) As this world doesn't exist, GDAL is there to fill in the gaps. I'd say that it is OK to have some ad-hoc rules to accomodate for data found in the wild (but I'm not sure there has been data released with the NGA's profile yet ?) > even spatialreference.org > is still using "Mercator_1SP" for the OGC WKT. spatialreference.org is not really maintained AFAIK, and is partly based on an old GDAL version. So I wouldn't consider it as an authoritative source. Even -- Spatialys - Geospatial professional services http://www.spatialys.com _______________________________________________ gdal-dev mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/gdal-dev
