Anyone know how to get a GML file to show as an overlay on Google Maps? To be honest I don't know my GML from my KML, or my ETRS89 from my WGS84, as this topic is completely new to me.
A bit of reading that I understood suggests that I have to convert GML to KML first, though it seems that process may corrupt the data and move the polygons, allegedly by up to 15m, which isn't acceptable.
I've downloaded some free software: GML Viewer from Snowflake Software, which seems to show the GML file, but it's a bit klunky, and what I really want is to overlay it over Google Maps' hybrid view, so I can see roads and the satellite image too. Maybe QGIS which I've also read about would be a better tool to use?
Any ideas or pointers to tutorials very welcome.
Best Answer
Try installing QGIS, and then installing the OpenLayers plugin from within the Plugin manager in QGIS. Via this you can load a Google hybrid layer as background. Here is some info and a guide:
http://www.digital-geography.com/qgis-plugins-openlayers/#.VCFqs5R_tTI
Beware though that in the latest version of QGIS, you will find the OpenLayers plugin, once installed, under the menu named Web, rather than plugins.
After that you can try to add your GML file as a regular vector layer in QGIS. If 'on the fly reprojection' is on it should match up with the background map.
I'm not sure how much of an error the reprojection from the original coordinate system to the Google maps Pseudo Mercator will create however.