On Wed, Apr 18, 2012 at 03:57:52AM -0700, Bob Pawley wrote: > I have, lets say, eight rows each containing a linestring, that, > when put together forms a closed shape or polygon. > > I can fairly easily detect one of the linestrings in this polygon. > > Since each linestring has a endpoint at (or near) the startpoint of > the next linestring in the polygon, I am wondering if there is a > method of detecting the other linestrings, that forms a closed > polygon, from that one contact. > > From this I would compare the shape to known shapes to identify it.
topology.GetRingEdges does the walking around a ring, starting from an edge. You'd have to build the topology first, making sure that endpoints do close. A tolerance >= the max distance between those endpoint might be enough. --strk; ,------o-. | __/ | Delivering high quality PostGIS 2.0 ! | / 2.0 | http://strk.keybit.net - http://vizzuality.com `-o------' _______________________________________________ postgis-users mailing list postgis-users@postgis.refractions.net http://postgis.refractions.net/mailman/listinfo/postgis-users
