[OSM-talk-be] some thoughts and remarks about border mapping

[Lennard]

ivom wrote:

> I would like to second Ben's idea of starting to map borders with 
> relations. A nice example which demonstrates borders mapped by relations I 
> found near Karlsruhe:
> 
> http://www.openstreetmap.org/index.html?mlat=49.014750749784966&mlon=8.308414136442622&zoom=13
> 
> Check what hangs on the river Rhine in terms of relations. I think this is 
> an interesting example what thing could start to look like with respect to 
> borders.

To make it easy for all here:

The middle of the Rhine is a way, tagged:

name = KA Stadt BW
created_by = Potlatch 0.10b
boundary = administrative
admin_level = 4
source = pi x D. korr. nach: GADM

It is part of the following relations:

Relation 22027
name = Karlsruhe Regierungsbezirk
boundary = administrative
created_by = Potlatch 0.10b
type = boundary

Relation 22046
name = Baden-Würtemberg Bundesland
boundary = administrative
type = boundary

Relation 22049
name = Karlsruhe Stadt
created_by = Potlatch 0.10b
boundary = administrative
type = boundary

Relation 23140
name = Rheinland-Pfalz Bundesland
boundary = administrative
type = boundary
border_type = state

So the way is tagged with the highest admin_level, and it renders as the 
highest level border that way. This is also what Ben suggested. And 
thanks to the relations, you can still extract the correct and full 
border for any admin_level, if you want to generate custom topographical 
maps.

I would suggest keeping a list on the wiki of relations used for 
boundaries in Belgium. This should ideally* keep people from generating 
multiple relations for the same border.



* Right, Ivo? Since you made a new relation for LF30, while mine was 
already on the map for a few weeks and in the wiki. I'll be connecting 
yours and mine shortly, thanks to a trip to Puyenbroeck yesterday. :)

-- 
Lennard