[OSM-talk] area_with_holes as alternative to multipolygon relation

[Robert Vollmert]

Hello,

On Mar 3, 2008, at 18:03, Frederik Ramm wrote:
> Until now I was unaware that we currently require the outer/inner ways
> of polygons to be clockwise/anticlockwise. It seems that some
> renderers work better if that is the case but nowhere is it a
> requirement.

That's how I read http://wiki.openstreetmap.org/index.php/Relations/ 
Multipolygon. And tagging multipolygons as in my proposal (i.e., tag  
the hole as a separate area) didn't seem to work well with either  
mapnik or osmarender. From what I remember of reading the code, both  
renderers skip areas with role=inner when rendering.

>> In particular, with the proposed
>> relation, it's not necessary to create duplicate ways (clockwise and
>> anti-clockwise) for holes with properties.
>
> Who said this was necessary today?
>

The wiki. And I've seen other people tag like that. I'll update the  
wiki later if nobody objects, and see what I can do about the renderers.

Thanks!

Cheers
Robert