On 8 Feb 2008, at 11:26, Andy Allan wrote: > On Feb 8, 2008 11:09 AM, Artem Pavlenko > <[EMAIL PROTECTED]> wrote: > >> We can make osm2pgsql or coastline tools to create polygons, but why >> not create them in the first place ? >> Can someone enlighten me, please ? > > If I wanted to draw the rivers as light blue* with dark blue > riverbanks, wouldn't storing them as polygons would make this hard? I > don't think it would be easy to work out which sections of the > polygons are where the river continues as opposed to being the > riverbank.
OK, valid point. > > If we store the riverbanks, then we can pre-process to our hearts > content using osm2pgsql and the like. That way I could have riverbanks > as polylines and rivers as polygons and render them as I see fit. The > pre-processing could work very similarly to the coastlines, using a > left- or right-hand side rule and continuing the riverbank where one > way joins onto the next to construct the polygons required. Can relations help here ? > > Cheers, > Andy > > * As I think more and more about contours, and semi-transparent > renderings and so on I realise that most area-fills will be > translucent with edges on my maps, so we need to avoid abutting > polygons if we aren't intending to represent an edge. _______________________________________________ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/cgi-bin/mailman/listinfo/talk