On Jul 19, 2010, at 8:51 AM, ext Anne Blankert wrote: > > Hello Bart, > > My 2 cents: > In my opinion it is quite difficult for users to discover: > - OpenStreetMap, Google, Bing, Yahoo etc. use a projection called > 'SphericalMercator' > - 'SphericalMercator' in OpenLayers uses code 'epsg:900913'
I think this is reasonably well documented in http://docs.openlayers.org/library/spherical_mercator.html and if you search for: http://docs.openlayers.org/search.html?q=google+projection You get that as one of the results. (Not as highly ranked as I would like, I'll admit, but it is there.) > - there exist multiple aliases for 'epsg:900913' and some services > prefer alias epsg:3857 or epsg:102113 over epsg:900913 > - how to override the default openlayers sphericalmercator epsg code > with an other epsg code This being supported is something I'd question ;) Until very recently, I'm pretty sure it was not at all possible to do this, so it's not really a surprised that it isn't well documented, in my opinion. > - discover that the override produces side effects in measurement and > mouseposition (and other functions, such as click-events...?) > - how to solve the side effects, by adding code: > OpenLayers.Projection.addTransform("EPSG:4326", "EPSG:3857", > OpenLayers.Layer.SphericalMercator.projectForward); > OpenLayers.Projection.addTransform("EPSG:3857", "EPSG:4326", > OpenLayers.Layer.SphericalMercator.projectInverse); > > But instead of solving this in the library, this can also be part of the > documentation. Maybe that documentation already exists and I've > overlooked it? No documentation like this exists at this time that I'm aware of. -- Chris > > Cheers, > > Anne > > On 7/19/2010 1:15 PM, Bart van den Eijnden (OSGIS) wrote: >> Hi Anne, >> >> check the example (first couple of lines in comments): >> >> http://trac.openlayers.org/browser/trunk/openlayers/examples/web-mercator.js?rev=10384 >> >> So that's up to the application to provide (at least for now). But I can >> also see that's not really easy for end-users. >> >> What do other people think about providing the EPSG aliases by default in >> the OL library? > > > _______________________________________________ > Users mailing list > Users@openlayers.org > http://openlayers.org/mailman/listinfo/users Regards, -- Christopher Schmidt Nokia _______________________________________________ Users mailing list Users@openlayers.org http://openlayers.org/mailman/listinfo/users