[OSM-talk] shp2osm.pl: duplicated way nodes

[Jukka Rahkonen]

David Carmean <dlc <at> halibut.com> writes:

> I'm trying to import some shapefiles with areas into JOSM; so far I haven't 
> been able to get "closed" ways.
> 
> I just tried shp2osm, and I get "Duplicated Way Nodes" errors in the 
validator.
> 
> I've also tried a two-step process with a couple of tools, DNRGarmin and
ExpertGPS. 
> These can produce GPX from SHP, but when I convert them to a data layer
 in JOSM 
> I end up with Unclosed Ways (after I tag them).
> 
> Has anyone found an automated way to import areas from shapefiles?

Hi,

Polygons are stored in that way in shapefile format. Starting node is repeated
as the end node, thus triange shaped polygon has four coordinate pairs. I don't
know if shp2osm is even trying to merge the starting and ending node for making
valid OSM polygons. I guess that it can be done manually by selecting the
duplicated nodes and merging them with OSM. In addition, each is shapefiles each
polygon is stored as a separate shape and converting adjacent areas will yield
even more dublicated nodes.
I don't believe that GPX format has any support for areas and it may well be
that all shp to gpx conversion programs are making dublicated nodes.