[OSM-talk] Parcel data

[Anthony]

On Mon, Sep 21, 2009 at 1:38 PM, Pieren <pieren3 at gmail.com> wrote:

> On Mon, Sep 21, 2009 at 5:34 PM, Anthony <osm at inbox.org> wrote:
> Hi Antony,
>
> Here in France, we also have access to the land registry WMS for the
> whole country (only raster images, not the shapefiles excepted for one
> "county" who released also the parcels as shapefiles).
> We use this source for buildings, street names and addresses but the
> data are not always up-to-date.


This data is definitely very up-to-date.  It is used by the county to impose
property taxes, so it has to be up-to-date.  They offer new files weekly.

But I can only speak for my country. I can understand the temptation
> to import everything when you have a bunch of geodata available but
> ask yourself if it is really valuable for OSM (I don't have the
> answer).
>

I basically just want the address info.  Having the parcel polygons is a
bonus, but if it proves to be too difficult to maintain I could just move
the data to the ways as an interpolation.

Also, remember, keeping all of France (population 61 million) up to date is
much harder than keeping Hillsborough County, Florida (population 1 million)
up to date :).

I don't know, I hope I can run a script regularly to provide a list of
changes, and take it from there.  But worst case scenario I guess I can just
remove everything.  Which gives me an idea.  I guess I should add a
hcparcel:verified=no tag to everything I import.



On Mon, Sep 21, 2009 at 1:28 PM, Frederik Ramm <frederik at remote.org> wrote:

> Anthony wrote:
>
>> Any other suggestions?  Objections?
>>
>
> Just my usual one: Please make sure that where you have polygons sharing a
> common border, create an individual way in OSM for this border and use a
> multipolygon relation for each of the neighbouring parcels so that they may
> share the same way and nodes, rather than importing two sets of nodes on top
> of each other (one for parcel A, the other for parcel B).


Thanks.  I was planning on matching up the shared nodes (they are duplicated
in the source data), but I didn't realize you could create a shared way.
I'll figure out how to do that before the import.  Good suggestion.

This leads me to a question.  If I mark the addr:housenumber on the
multipolygon relation (that's where it would go, right?), will that show up
on the map in the two main renderers?  Or should I add a node for this?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstreetmap.org/pipermail/talk/attachments/20090921/296cf538/attachment.html>