[OSM-talk-be] historische kaarten als basis??

[Luc Van den Troost]

On Thu, 2008-08-14 at 14:40 +0200, Lennard wrote:
> Luc Van den Troost wrote:
> 
> > It would also *roughly* get us somewhere if all streets (or these near
> > administrative borders) were tagged with postcode. 
> > Something like borders or postcode should be needed for the decent use
> > of OSM in navigation and lookups... This would give the borders at the
> > most important points: where you can cross / see them. 
> 
> But how will you get the postcode, on a large scale? Is the Belgium 
> postcode copyrighted, like it is in e.g. NL and the UK?
> 
Postcode in Belgium is a bit less sofisticated as in NL. It only mostly
only has one number for one 'gemeente' or 'deelgemeente'. 
For Antwerpen - for instance - the (public) official streetname list
will give for every street what district (postcode) it is in. If a
street goes trough, or borders several districts/postcodes, or even a
neighbouring city, it will mention what housenumbers are in what
district/postcode. 
Where you go from one village / city to another, on most places the
streetname will change, and/or you will have a sign with the village
name on it (here in Belgium we have 2 kind of roadsigns, the 'yellow'
ones put on the city administrative border, and the 'white' one put on
the border of the build-up area, and where allso a general speedlimit of
50 will be. 



> What I've thought about doing during my mappings in Oost-Vlaanderen is 
> to make a note of every placename sign that delimits the municipality, 
> and create an area with those, and the same with bebouwde kom signs. 
> Then with every new road that's mapped that has such a sign, I would 
> create a new node in the area, and place it correctly. That would create 
> an area that's only an approximation of the real borders, but for 
> navigation purposes, it would be enough. It could then be further 
> refined using local knowledge.
> 
Look up the wiki about borders.... there is some clarification there. 
A border has nothing to do with an area. A border is something comon,
for instance between Antwerpen (berendrecht) and Beveren (Doel) on the
other side. 
Most convenient then (in my opinion) it is tagged as admin_level 8,
meaning city border. 
But at the same time this city border is allso the border of the
'deelgemeenten' Doel and Berendrecht, it is the border of 2
'arrondissementen', and it is the border between 2 provinces. 

All these other 'functions' of the same line then could be grouped in
'relations', (something that goes beyond my competence, but that's as
far as I understood it. 



> I didn't get around to doing this just yet, because I was waiting for 
> you guys to find a proper and legal source for all municipal borders. :) 
> Should I just start doing it this way and of course tag it with 
> note=Extrapolated; source=Survey ?
> 
Off course you could tag the individual border points.
As soon as you have some you can put them together in a border, and more
detailed points can be entered later. 
For the build up area you should probably not combine them in a 'border'
cause they are not. The function of 'area' is meant for this. You could
use them for marking an area in the map as 'area=yes' and 'landuse =
residential' or something like that, have to look it up what the options
are.  The signs in this case do not always reflect reality and are more
to be considered as a roadsign - in my opinion -