[mkgmap-dev] Multipolygons and basic question on polygons with holes

Fri Jan 1 13:43:33 GMT 2010

Hi Steve,

> I've no idea, I've been wondering too.  It could be that the way Mark is 
> doing the sea/island polygons is the right way, except that if I'm not 
> mistaken his method only works with a TYP file, whereas it is clearly 
> possible to do this without since the MetroEurope maps don't have a typ 
> tile.

Yes, my alternative scheme for sea/land does require a TYP file so it
can't be the method used in the Garmin maps.

What would be very useful is if the IMG format supported a polygon
type that cut a hole in the polygon below it. Are we sure that such a
beast does not exist? How about trying to find an unlocked Garmin map
that contains sea with islands and examine it carefully?

Cheers,

Mark