[OSM-talk] Wood & Park mapnik carto anomaly?

[Martin Koppenhoefer]

2014-09-17 10:43 GMT+02:00 Dave F. <davefox at madasafish.com>:

>  On 16/09/2014 14:59, Martin Koppenhoefer wrote:
>
>
> 2014-09-16 15:32 GMT+02:00 Dave F. <davefox at madasafish.com>:
>
>> I find it surprising something as arbitrary as size is used as the
>> defining factor. Comparing actual tags would surely make more sense.
>>
>
>
> well, size surely has some correlation with importance. For practical
> reasons it is generally working quite well to have first render the bigger
> stuff and then render the smaller stuff on top, because it leads typically
> to less covering.
>
>
> This, IMO, is lazy rendering & should be discouraged. To allow the smaller
> stuff to display is one of the reason mutli-polygons were developed.
>



no, multipolygons have nothing to do with this issue. Multipolygons are
there to cut holes into polygons or to build polygons from outer ways which
are also otherwise used. Here they would not serve at all, as the park and
the wood both occupy the same area (locally).



> Refer also to the layer tag which is disappointingly under used by
> renderers.
>


yes, it is indeed underused, but it also has nothing to do with the issue
here, as both objects are on the same layer.




>
>  In this particular case more detailed mapping of the tree areas could
> solve it, e.g. split the wood object at the cutting roads and waterways,
> but admittedly in this case by looking at the bing aerial imagery it seems
> indeed to be a continuity of trees on both sides of these.
>
>
> That's mapping incorrectly to suit the renderer &, for obvious reasons,
> should be criticized.
>
>

how would splitting an area be incorrect? It is just another representation
of the same. There are infinite correct ways to representate the same
object.

cheers,
Martin
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