In my fork of ogr2osm (https://github.com/andrewguertin/ogr2osm/), multilinestrings are currently handled by creating a relation, putting tags on the relation, and putting subgeometries of the multilinestring as members of the relation. This is analogous to how, e.g., multipolygons are handled.
Paul Norman has reported that when working with roads data from http://www.tol.ca/Services-Contact/Open-Data/Open-Data-Catalogue, this handling was not useful to him. Instead, the useful handling would be to create no relation, and put the tags from the multilinestring on each way. I've investigated the file, and found three distinct classes of multilinestrings in it: 1) a dual carriageway 2) cases where a turning circle, loop, or branch in a road was combined with the main road 3) complicated intersections/interchanges In all of these, the standard representation in OSM would be to have no relation and tags on the ways. My question, then, is whether this is normal. Do other files have multilinestrings like this, and would benefit from changing the default handling--or is this file just poorly made, and should be fixed in file-specific translation routines? Conversely, do other files have multilinestrings that should be turned into relations, and would be harmed by changing the default handling? As a final note, Paul has posted a patch at https://github.com/andrewguertin/ogr2osm/pull/2 . This patch changes the parsing of multilinestrings to work as desired. However, I'm tempted to say that a better change would be to continue parsing as-is, and later modify the structures as desired. This would be a bit more flexible and mesh better with other envisioned-but-uncoded data cleanups like flattening any relations with only one member. --Andrew _______________________________________________ Imports mailing list [email protected] http://lists.openstreetmap.org/listinfo/imports
