[OSM-talk] Australian suburb boundaries

Franc Carter franc.carter at gmail.com
Sun Feb 22 08:01:30 GMT 2009

On Sun, Feb 22, 2009 at 6:53 PM, Frederik Ramm <frederik at remote.org> wrote:

> Franc,
> Franc Carter wrote:
>> The talk-au list has been discussing the import and the current thoughts
>> are here:-
> We did it almost the same way for a German administrative boundary import
> in late 2008. Your Wiki table doesn't include the obvious relation tags
> (type=multipolygon, boundary=administrative, admin_level=something) but I
> guess these were implicit and so you didn't mention them? Also, for the
> benefit of relation-unaware software, we usually tagged the member ways with
> "boundary=administrative, admin_level=x", with x being the smallest
> admin_level of all relations that used this way. We did not add any names or
> "state:left=x, state:right=y" to the ways though.

This is something I was unsure about - the talk page for this had lots of
conflicting opinions ;-(

> We did not see a need to simplify the lines in our case and I cannot
> imagine Aussie borders being so detailed that this should be necessary but
> you'll know better.

There's a lot 'over specification' in the data - 10's of points where one
for each end would be fine.

> Multipolygons now support multiple outer rings (see the multipolygon
> relation talk page in the Wiki - the "advanced multipolygons" secion really
> needs to be moved to the main multipolygon page, it is actually in use and
> not just "talk"), so that solves your problem of disjoint suburbs.

Ok, I'll have a read and wrap my head around it

> When actually running the upload (we used the bulk_import.pl for this after
> creating a suitable .osc file) you should make sure that you *not* attempt
> to first upload all the nodes and then all the ways and then all the
> relation (which is what we did), because unless the process is over in an
> hour or so, you will have eager mappers removing your nodes for obvious lack
> of use! In the end I had to download the hourly diffs while I was importing,
> searching for "my" node IDs and checking who deleted some, then undelete
> them with another script running in parallel, so that my import script would
> find the nodes it expected to see. So the lesson learned here was, try and
> upload a way as soon as you have the necessary nodes for it, and not at the
> end.

I thought of this ;-) The file has the data node/way specification just
before it is first needed, so hopefully there will
only be a short period where the data looks inconsistent


> Bye
> Frederik

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstreetmap.org/pipermail/talk/attachments/20090222/a5126c32/attachment.html>

More information about the talk mailing list