[OSM-dev] Looking for guidance on interpreting multipolygon relations

[Frederik Ramm]

Hi,

> In practice you probably want a park with no holes and a lake with holes
> for each of the islands. That matches the current Bettersea Park
> http://www.openstreetmap.org/?lat=51.47919&lon=-0.15541&zoom=16&layers=B0F
> 
> The island appears with the park rendering because it is a hole in the
> lake. It does not require any individual tagging.

That looks good. It is sometimes difficult to come up with the right
tagging ideas but I try think in statistics.

If someone asks me for the area of parkland in London then I would
probably include the bits of park taht are covered by a lake, so the
lake should probably not be a "hole" in the park.

If, on the other hand, someone wants to know the total size of all
lakes in London, then I would probably not want to include the area of
the islands in the figure, so it makes sense to cut them out.

Unfortunately it is not always that clear ;-)

Bye
Frederik

-- 
Frederik Ramm  ##  eMail frederik at remote.org  ##  N49°00.09' E008°23.33'