[OSM-dev] PostGIS query "Crossing ways"

2016-09-11 Thread Mike N
Given a PostGIS database populated from OSM data by osm2pgsql, and 2 sets of lines (such as the selection of all footways and the selection of all roads) what function or series of functions will result in a list of locations where footways cross roads without any OSM connecting node? (the

Re: [OSM-dev] PostGIS query "Crossing ways"

2016-09-11 Thread Ian Dees
On Sun, Sep 11, 2016 at 3:54 PM Paul Norman wrote: > On 9/11/2016 8:20 AM, Mike N wrote: > > Given a PostGIS database populated from OSM data by osm2pgsql, and 2 > > sets of lines (such as the selection of all footways and the > > selection of all roads) what function or

Re: [OSM-dev] PostGIS query "Crossing ways"

2016-09-11 Thread Stefan Keller
Mike, See below a solution which runs standalone in a PostGIS db. This SQL looks little bit scary - but I'm open for simplifications :-). It would have been much easier to calculate in a topological structure like OSM given nodes and list of nodes (=ways)). The main query comes after the remark.

Re: [OSM-dev] PostGIS query "Crossing ways"

2016-09-11 Thread Paul Norman
On 9/11/2016 8:20 AM, Mike N wrote: Given a PostGIS database populated from OSM data by osm2pgsql, and 2 sets of lines (such as the selection of all footways and the selection of all roads) what function or series of functions will result in a list of locations where footways cross roads