I can't comment all details, some general ideas. Maybe someone else
will step in?
Jaak Laineste wrote:
I have now done so for admin_level=8 in Hiiu, Saare and Pärnu maakond.
[I'll revert that if agreed here]
How does it look like on Mapnik, can you give permalink where you have
defined it so?
How about (some special examples):
http://www.openstreetmap.org/?lat=59.027lon=22.7512zoom=13layers=B000FTF
http://www.openstreetmap.org/?lat=58.202lon=22.3945zoom=12layers=B000FTF
http://www.openstreetmap.org/?lat=58.35lon=24.5058zoom=12layers=B000FTF
And some counter example (only having coastline+relation membership with
admin_level=8 -- not modified by me):
http://www.openstreetmap.org/?lat=58.9487lon=23.5454zoom=14layers=B000FTF
(Some islets having problems at the moment ... will fix that)
In visual rendering the arbitrary border in sea looks better option.
But technically (geoinformatically and legally) this is just
cartographic hack. Paper map makers have freedom to use a lot of
visual tricks, like drawing fake borders, they also move POIs (and
also roads, rivers etc - depending what is more important) to fake
locations to make them visible better. In digital databases like OSM
you cannot do it. Or if we really need to do it, then it must be
correspondingly tagged (fake border, fake location etc).
IMO the proper way to solve it would be to have Mapnik rendering
fixed: if line is both city border and coastline, then it should not
be rendered as border. This is how also paper maps are usually done.
Can you add ticket to the mapnik trac, I think layout bugs are handled
through it ?
If
Narva city municipal border (and their jurisdiction) ends with riverbank,
and there is some federal land before state/EU border then this should be
like that in the map also.
Question: Is this the case or is it just some assumption?
Well, just my assumption. Actually
http://vana.narvaplan.ee/Linnakaart.pdf shows that the city border is
in the middle of the river (like you suggest), but this could also be
subjective view of the municipality. Or Maa-amet files are wrong.
By the way, http://www.narvaplan.ee/index.php?lang=etmenu=5page=0
has also Vector map of Narva (in terrible DGN and DWG formats, i.e.
probably without attributes, but with buildings). Import?
Similar thing with Tallinn and Aegna island
(which is part of Tallinn, Central linnaosa); Naissaar is part of Viimsi
vald, so it is quite a mixture there if you try to divide sea between them
reasonably. I've seen that on some maps Võrtsjärv has been divided between
counties, but in Maaamet latest data has admin borders on shoreline.
Actually about every map I have seen contains the border(s) in
Võrtsjärv.
Yes, it is common on paper maps. It does not mean it is really
correct. Maaamet's http://xgis.maaamet.ee/xGIS/XGis does not have any
admin boders on Võrtsjärv, Peipsi, Sea and Narva River. It also does
not look like a cartographic accident, as on Emajõgi and smaller lakes
there are admin borders shown. Either: Maaamet knows that this is
right or they just avoid the issue of vaguely defined (undefined)
border areas.
I wrote emails to Narva city and Võrtsjärve sihtasutus, lets see if
they answer anything.
ps. We have the final expert questions from KYSK for our project, and
deadline until 11.02 to answer them.
Jaak
___
Talk-ee mailing list
Talk-ee@openstreetmap.org
http://lists.openstreetmap.org/listinfo/talk-ee
