2017-10-25 16:40 GMT+03:00 Stefan Keller wrote: > 1. My ceterum-censeo is, that we really need a polygon type in OSM. > This would make mapping, and many written and unwritten(!) rules much > easier (not to forget software).
What exactly are we missing on this polygon topic? Because currently OSM data is in a non GIS database (no geometry column). So there are no geometry types as such, just building blocks which are later used by software like osm2pgsql which creates a GIS database and geometry column. So polygon type would not be a "topology rule", as topology rules can only (?) be applied to geometries. The only thing I could think of is having a pre-geometry rules of following types: 1. If way has landuse tag, it should be closed 2. If relation has landuse tag, its ways should form a (multi-)polygon 3. Node cannot have a landuse tag This is for landuse only, but the same type of rules could be written for other tags like building etc. Then there are two tasks: * Fix currently incorrect data * Introduce these rules to editors and/or api so that new errors could not be introduced. (does not necessarily has to be done in listed order) And actually second point can already be done now. JOSM does complain about unclosed polygons, but it does allow saving them anyway and check does not work on partially downloaded multipolygons (logical thing as this could be a multipolygon of a veeeery large/complec country border). Maybe editors could start introducing some simple but mandatory checks, for example not allowing saving of non closed ways with building=*? -- Tomas _______________________________________________ talk mailing list talk@openstreetmap.org https://lists.openstreetmap.org/listinfo/talk
