On 11-01-08 05:44 , Xan wrote: > > The idea is to download a WMS of an > area and edit offline
It's not that hard; just a small matter of scripting. Doing it by hand would be tedious. WMS queries are just URLs. For instance: http://wms.ess-ws.nrcan.gc.ca/wms/toporama_en?REQUEST=GetMap&SERVICE=wms&VERSION=1.1.1&SRS=epsg:4326&BBOX=-72,45.35,-71.85,45.5&WIDTH=800&HEIGHT=600&FORMAT=image/png&LAYERS=vegetation,builtup_areas,hydrography downloads an 800x600 PNG image. Note the BBOX, WIDTH, HEIGHT and LAYERS parameters. Check the documentation for the WMS you want to use for the values of these parameters. For each image you download, you're going to have to create a World File <http://www.kralidis.ca/gis/worldfile.htm> so that your GIS system knows where the pixels are and what scale to use. For PNG images, the appropriate file extension for a world file is PGW. Next, you're going to have to tile these images and translate them to the right projection. gdal_merge will tile them (http://www.gdal.org/) and gdalwarp from the same site will translate them to the Spherical Mercator projection (EPSG:3857) that OSM uses. Finally, check the usage restrictions on the WMS. Some operators take a dim view of scraping their data, so govern yourself accordingly. cheers, Stewart _______________________________________________ newbies mailing list [email protected] http://lists.openstreetmap.org/listinfo/newbies
