[mkgmap-dev] warn against head-to-head or back-to-back coastline ways

Mon Nov 14 08:57:02 GMT 2011

An OSM newcomer edited the coastline last weekend. He had deleted 
existing natural=coastline ways and replaced them with his own edits, 
and he forgot to connect the nodes.

I fixed that by extracting the natural=coastline ways from the 
finland.osm.pbf with Osmosis, loading it into JOSM and addressing the 
validator complaints.

All well and good, but the flooding did not cease today. I was puzzled.  
JOSM did not complain anything. mkgmap only complained the usual stuff 
about broken coastlines, e.g., when it sees an island polygon on firm 
ground, or stuff like that.

Finally, it occurred to me that the new coastline sections were the 
wrong way around (land to the right, instead of land to the left).

Could mkgmap please issue a warning when it notices that a 
natural=coastline way is connected to a natural=coastline way that runs 
in the opposite direction? I will file a similar bug against JOSM.

Best regards,

	Marko