[mkgmap-dev] multipolygon with outer polygon within inner polygons

Fri Feb 12 18:26:31 GMT 2010

> Hello
>
> On 12/02/10 10:24, Minko wrote:
>> Simplification looks like this,  where the two
>> vertical border lines are not supposed to be there:
>> http://img63.imageshack.us/img63/1002/bordersnl5.jpg
>
> Thanks for that image as it shows the problem clearly.
>
> If the boundaries were being drawn as areas, then the lines would
> not be seen (or not much anyway) since they would be zero width.
> However since the borders are drawn as lines you clearly see the
> connecting lines.
>
> I think that the best way to solve this is for mkgmap to convert
> to multipolygon into separate lines in the case of boundaries.
>
> ..Steve

Steve,

I have two solutions:

1st: We might add a mkgmap option to disable multipolygon processing for 
boundaries.

2nd: the multipolygon code should not remove the boundary tags from the 
singular ways. Additionally the polygons created by the multipolygon 
code could be tagged with mkgmap:mp_boundary=yes. This tag could be 
evaluated in the style definition so the style could differ between the 
polygons created by the mp code and the lines not touched by mp code.

What do you think? (I am not an expert of the style processing)

WanMil