Martin, > It is not as easy as it sounds like. Actually we often do not have > this information (directly) in OSM. What you could do is: > * use the landuses and extend them slightly (to also get the streets, > which are sometimes enclosed in the adjacent landuse but actually > shouldn't).
yes, this is what I tried > * You could also use residential roads and extend them (draw a hull > around them). I was considering something like this as a last resort :) but yes, when looking at a map generated from OSM, visually it's quite clear where city boundaries are - where the streets stop :) > * Last but not least you should look for polygons tagged with > place=town/city. These are IMHO actually the bounds of the settlement > (but mostly that's nodes, not polygons in current OSM). I looked at this, and these are usually points for Hungary, marking the center point of the city. >> One possibility seemed to be to go with: >> boundary = administrative && admin_level = 8 > > -1, as you already discovered, these are administrative boundaries and > not what you are looking for. well yes, but then again, a proper administrative boundary would be fine with me. > yes, we have quite incomplete data for city extensions as a polygon. > One of the reasons is IMHO, that the main mapnik map uses external > data for builtup areas (from natural earth), so people are less aware > that there is something useful missing. I see. so basically what is not natural, is considered to be man-made? Akos _______________________________________________ dev mailing list [email protected] http://lists.openstreetmap.org/listinfo/dev
