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Hi, some houses in my neighborhood are mapped as multipolygons while it's only simple shapes that could be represented as only one surface...

Do you have any idea of what to do? Thanks in advance for your help! :)

Here is an example:

house mapped as multipolygon

asked 04 Feb '17, 09:40

thomaskuntzz's gravatar image

accept rate: 0%

These houses are not mapped as multipolygons in the OSM sense (i.e. they don't have a relation combining the parts) - or at least they didn't until you added one! I would not recommend doing that, since multipolygon relations with touching outer rings are considered invalid.

Instead, use the JOSM editor's "join overlapping areas" function to combine the various rings into one.

It appears that the data you are looking at is the result of an import of Cadastre data in 2010 (https://www.openstreetmap.org/changeset/5056952) that was improperly reviewed and hence these issues were not detected ahead of the import. If you should find that there are too many problems to handle manually, there's also the option of deleting the faulty import altogether.

permanent link

answered 04 Feb '17, 10:07

Frederik%20Ramm's gravatar image

Frederik Ramm ♦
accept rate: 23%

Yes, the house was made up of several areas so I merged them together...

There is a large number of houses that are the result of this Cadastre data import (by the way, your link seem to be broken) and that are mapped the same way as this one, that is as multiple surfaces instead of one.

So I'd like to clean up all this a bit and I don't know what to do...

(04 Feb '17, 10:36) thomaskuntzz

Remove the ) after the link for it to work. Install the JOSM editor and learn how to use it; while the ID editor you are using is fine for everyday mapping activities, JOSM has a broader set of tools for more complicated operations like cleaning up a botched import.

(04 Feb '17, 10:39) Frederik Ramm ♦
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question asked: 04 Feb '17, 09:40

question was seen: 1,998 times

last updated: 04 Feb '17, 10:39

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