On Thu, Apr 17, 2008 at 12:19:19AM +0200, Iván Sánchez Ortega wrote: > El Miércoles, 16 de Abril de 2008, Christopher Schmidt escribió: > > On Wed, Apr 16, 2008 at 11:28:32PM +0200, Martijn van Exel wrote: > > > yesterday a colleague approached me asking why OSM data doesn't comply to > > > the Simple Feature specification[...] > > > > Is this something that is being considered? I guess it would be easy > > > to check for self-intersection upon adding / changing a polygon. > > > > "Easy"? I don't think that this is true... determining self-intersection > > is hard. > > IMHO, checking for self-intersection is as easy as the Simple Features > Specification is simple ;-) > > > Now, really, OSM data doesn't comply with OGC's Simple Features spec because > it doesn't need to in order to work. That's it. > > Even more - if OSM's API would support SFs, the number of geometries would > raise from 3 (nodes, ways, relations) to 6, increasing the complexity of > *any* tool that wants to work with the API.
7, really, since Simple Features doesn't describe relations, and OSM would still need them. > About importing into MS SQL server: Has your colleague browsed the subversion > repository? Namely, /applications/utils/export/ - I guess that osm2pgsql > could be hacked to work against MS SQL instead of Postgres. Or import into > postgres, dump the data into WTK, import into MS SQL. Probably not. PostGIS doesn't prevent self-intersecting polygons, so he would probably have the same problem taking the data from PostGIS -> SQL server. Regards, -- Christopher Schmidt MetaCarta _______________________________________________ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/cgi-bin/mailman/listinfo/talk
