Quote Originally Posted by Falconius View Post
Maybe by converting lines to shapes?
They are shapes already

What I think is most likely though is that they did it in a raster program, which would be fairly simple in comparison I'd think.
No, it was in Inkscape, so i need tutorial for Inkscape.

I made a little pic previously, although it was more about giving blurred border, but the principal is the same. Hope it helps.
Thanks a lot, it works. But i should to test it on my map.