0

I'm looking at building a simple routing application using pgRouting. I'm running on Windows 10 at the moment but could migrate to Windows Server at some point. I'm trying to figure out how best to import the data for the state of South Australia, Australia.

It seems there are two options to import the data:

  1. There is an official ESRI shapefile of the road network available from an SA government website. Import this using shp2pgsql.exe, and then build the routing topology using pgr_createTopology().
  2. Export an OSM file for SA (or perhaps Australia) from OpenStreetMap (downloadfabrik has one). Import this using osm2pgrouting.

Which of these is best?

As far as I can tell, the OSM data for South Australia is actually derived from (or at least incorporates) the official shapefile.

Are there good reasons to go straight to the source (seems slightly easier to import)?

Or has the OSM data been "massaged" in a way that makes it a worthwhile "value-add"?

0

check for topological errors. If you use OSM it is easier to update as more data is added to OSM than into shapefiles.

  • Thank you for your response. Can you be more specific? What kind of data am I likely to find in the OSM file that I wouldn't find in the shapefile? Especially as the former is based on the latter? – Fr Jeremy Krieg Oct 22 '18 at 23:04
  • OSM is not based on any other. It is independent, you can even add data which are absent in the shapefiles by digitizing satellite images that is available through the OSM editors. – neogeomat Oct 23 '18 at 20:32
  • I believe your comment is true in general, but for South Australia, it is my understanding that the bulk of the OSM data was uploaded from the official SA government shape file. This Wiki page documents the process: wiki.openstreetmap.org/wiki/Import/South_Australian_Roads Forgive me if I am wrong or have misunderstood something. – Fr Jeremy Krieg Nov 14 '18 at 12:25
0

There is a tool osm2pgrouting, which takes into account typical issues, that you may have with the OSM data. For example it may split a way into multiple segments to allow correct routing, and it will allow you to work with the imported data right away. https://github.com/pgRouting/osm2pgrouting

I don't know, what has been changed with the SHP file data you mention, but you won't be able to make use of osm2pgrouting, so you may have to fix data issues later yourself.

  • Thank you @dkastl for your response. I referred to osm2pgrouting explicitly in my post (sorry, should have bolded it or something). I understand in general that OSM data will be better quality that SHP and require less fixing, because of the open source "peer review" process. However, given that the shape file for South Australia comes from official sources (Local, State & Federal government departments that are responsible for such things), I was wondering if that situation might be different in South Australia. – Fr Jeremy Krieg Oct 22 '18 at 23:19

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.