[OSM-talk] multipolygon (lake) not rendering

Frederik Ramm frederik at remote.org
Mon Oct 26 13:53:11 GMT 2009


Anthony wrote:
>> A further problem arises when the hole boundary consists of multiple
>> ways, something that is allowed for advanced multipolygons, but you
>> would not be able to place the name of the island (or whatever) in this
>> scenario.
> You could if you used a second multipolygon with the "hole" ways as
> the outer, right?

That is correct.

> Do advanced multipolygons have to have an inner? 


> If so you could always use a boundary relation.

Yes; a boundary relation is just an advanced multipolygon by another 
name. People have even suggested to drop the relation type "boundary" 
altogether and name these "multipolygon" as well (the fact that it is a 
boundary can be seen from the bondary=something tag anyway).

Personally, I am hoping that we will (re)introduce a proper area data 
type some day because even though the multipolygons were a good idea at 
the time, they do seem a bit clumsy now.


More information about the talk mailing list