[mkgmap-dev] How do I get a blue sea?

Wed May 18 08:07:48 BST 2011

I use
generate-sea: extend-sea-sectors,close-gaps=6000,floodblocker,land-tag=natural=background

In the polygon style, I'm specifying a land-tag "natural=background" and not "natural=land" because the last one is often used to make islands in a lake. The background must get the second lowest draw order (sea is the lowest) so  if you use natural=land as background those islands in a lake are rendered under the lake.

BTW I have noticed in the default style there isn't a tag for natural=land or a another background. If you don't specify a background, this will cause 'ghosting' problems in Mapsource. When you zoomed in or out, it disappears. This effect only shows up in the later versions of Mapsource (6.16.x). You don't see it in Basecamp.