[OSM-newbies] sharing ways between areas

[Thomas Wood]

2008/12/23 Joe Richards <joefish75 at yahoo.com>:
> I am trying to put a large national park into the map here:
> Permalink to NZ map of Abel Tasman national park
>
> with the intention of making the area green and labelled as a national park.  It's a very big area so I've split it into about three areas.
>
> The problem is that the edges of the national park go (in some places) right up to the coastline, and so I've shared the coast as an edge.
>
> There are several problems now:
>  1. the coastline appears to have 'bled' back into the main land area, creating big pools of water in the middle of the land
>  2. the national park doesn't appear green, which was the main intention in the first place.  It's genuinely sectioned-off, ie no building in this national park, and only walking tracks etc.  I think the areas around this part of the map would look better with the national parks marked off (and ideally the rivers too).
>
> What should I be doing to fix these problems?
>

1 Coastline is always awkward to edit, you can usually break things in
unexpected ways from slight changes - the renderers are quite picky
about data correctness here.
2 Osmarender has some size issues when it comes to large areas.

Your permalink didn't come through the email properly, but from a
quick glance at the data, you've made the coastline around this region
into closed areas.
The correct method would be to overlap the national park boundary with
the coastline by reusing the nodes, rather than giving the coastline
tag to the whole area.

For others interested:
http://www.openstreetmap.org/?lat=-40.8892&lon=172.9639&zoom=12&layers=B000FTF
The error with the coastline is clearly visible in osmarender.

-- 
Regards,
Thomas Wood
(Edgemaster)