[OSM-dev] Fwd: Re: Advice sought on polygon-with-hole drawing

Cartinus cartinus at xs4all.nl
Fri Mar 14 05:19:03 GMT 2008

On Friday 14 March 2008 02:15:13 you wrote:
> Hi,
> > If I understand this correctly, then for a forested island in a lake
> > you'd need to have the island twice in the osm data. Once for the hole in
> > the lake and once for the forest on the island.
> No.
> Assuming for a moment that you really wanted to model the forest as a
> "hole in the island", which doesn't make a lot of sense to me since I
> don't generally map forests as holes in the country, but I understand
> it's only a example, then the island would be there only once, be part
> of two relations, one where it would play the "outer" role to the
> forest and one where it would play the "inner" role to the lake.
> Bye
> Frederik

I don't want to model the forest as a hole in the island. What I am talking 
about is an island and a forest that are completely coterminous. Since there 
are no holes in the forest it is a simple polygon and thus has no "outer" 


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