[OSM-newbies] sharing ways between areas

[Ævar Arnfjörð Bjarmason]

On Wed, Dec 24, 2008 at 8:27 PM, Thomas Wood <grand.edgemaster at gmail.com> wrote:
> 2008/12/24 Joe Richards <tenzin at penski.net>:
>> So can I summarize on how to fix this so you can check my understanding...:
>>  * I need to create some new nodes and ways which represent the area of the
>> national park, in some areas following the coast but a few metres "inside"
>> it's borders
>
> No
> The coastline way should be a linear feature
> The national park way should be a complete loop
> The two should overlap each other along the coastline, using the same nodes.

Practically speaking, if you have a boundary that shares the coastline
nodes your boundary won't be rendered. The boundary for national parks
usually extends beyond the coastline as well.

I usually draw these slightly beyond the coastline, as seen here:

http://informationfreeway.org/?lat=66.0040552506249&lon=-18.390442279736504&zoom=12&layers=B0000F000F

>>  * I need to split the national park into more areas because the current
>> ones are too big for osmarender
>
> Not sure yet about this, should be fine. It may even work if it was
> all a single area - it's fairly small (compared to others that were
> causing issues)

The only thing osmarender cares about is that for the extent of your
boundary there is at least one node on the way inside each z12 tile.
You can see if this is the case by using JOSM with the slippymap
plugin which shows you z12 boundaries.