[mkgmap-dev] Multipolygon problem

Sat Jan 8 08:28:10 GMT 2011

Hello all,

I have the following rule in my polygons style:

surface=sand [0x1b resolution 20]

The problem is the following multipolygon:
http://www.openstreetmap.org/browse/relation/1221199

This is a complex multipolygon which, in certain sections, uses the 
coastline to define the outer.  Parts of the coastline (and therefore 
parts of the multipolygon) have the key/tag pair surface=sand

The result is that mkgmap attempts to build a multipolygon for Port 
Philip Bay and fill it with sand, which is not ideal:
http://www.cferrero.net/maps/img/1.png

What I can't figure out is how to adjust my polygon style rules to avoid 
this happening.  Or tell mkgmap not to process multipolygons of type 
natural=bay

Neither of the following two variations of the rule makes any difference:
surface=sand & natural!=coastline [0x1b resolution 20]
surface=sand & type=!multipolygon [0x1b resolution 20]

Nor does
natural=coastline & surface=sand {delete surface}
make any difference whether I put it in the lines file or the polygons file

Does anyone have a suggestion on how to fix this?

Thanks!

-- 
Charlie