[OSM-dev] Gisify relations

[Andreas Kalsch]

Hi,

this looks nearly like what I need. But let me specify my need a little 
bit further. The script needs to be:

1) complete: all interesting nodes, all ways, all relevant relations - 
MultiPolygons for as many relations as possible
2) correct: decision LineString or Polygon for ways, interpretation of 
boundaries/multipolygons including holes (inner/exclave roles)
It seems that not all multipolygons are tagged with a certain order. But 
I want to include as many multipolygons as possible
3) performant: at best all transforming steps on the DB server - 
possible for both nodes and ways but not for boundaries/multipolygons.

I have solved nodes and ways, and I think the osm2pgsql script is the 
best starting point to understand how the boundaries are exactly 
working. I am currently not sure how to interpret the linearrings, 
because they can be made of several ways. But some polygons start with 
"inner" and then comes "outer", so I don't know to which "outer" the 
"inner"s belong to. This can be difficult if there are several outer. 
Unlike it is explained in the Wiki. And so on ... ;)

So thanks for your first replies, I will take a closer look into the 
scripts now.

Andi


Frederik Ramm schrieb:
> Hi,
>
> Andreas Kalsch wrote:
>> Is there a script to gisify OSM relations - a script which creates 
>> OpenGIS multipolygons or geometrycollections inside PostGIS or MySQL 
>> as WKT ?
>
> No but there's this:
>
> http://wiki.openstreetmap.org/wiki/Boundaries.pl
>
> It generates .poly files from relations. The .poly files are basically 
> text files with a list of lat/lons and I guess they could be converted 
> quite easily into something else. In fact, if you do a little bit of 
> Perl you could use the shapelib to create shapefiles directly from 
> above script.
>
> Bye
> Frederik
>
>
>