[OSM-dev] Determining if two linestrings are "similar"

Jukka Rahkonen jukka.rahkonen at latuviitta.fi
Mon Jan 7 10:37:07 GMT 2013


Hi,

OpenJUMP has two plugins for matching topologies

http://wiki.openstreetmap.org/wiki/Roadmatcher

http://sourceforge.net/projects/jump-pilot/files/OpenJUMP_plugins/More%20Plugins/Matching%20PlugIn/

They are written by good experts and they come with source code and
documentation and I guess they are worth having a look.

-Jukka Rahkonen-

Paweł Paprota wrote:
> Hi all,
>
> Here's an interesting problem I'm trying to tackle now in OWL...
>
> You have two linestrings and the task is to determine if they are
> "similar" or not. Similar means spatially "the same" as looked at by
> human eye at zoom level 18 on a slippy map :-)
>
> Note that the two geometries are not equal in ST_Equals sense. They
> don't have to intersect but can intersect or even be almost the same
> save for one node slightly moved.
>
> OWL right now shows some changes that in fact are non-changes - e.g.
> using simplify way feature of JOSM changes way nodes but preserves (or
> only very slightly changes) way geometry. It is not a change worth
> processing and showing to the user.
>
> I tried ST_HausdorffDistance[1] from PostGIS but for now it does not
> yield useful results or maybe I am misinterpreting them.
>
> Any ideas?
>
> http://www.postgis.org/docs/ST_HausdorffDistance.html
>
> Paweł
>
> _______________________________________________
> dev mailing list
> dev at openstreetmap.org
> http://lists.openstreetmap.org/listinfo/dev
>





More information about the dev mailing list