[OSM-talk] River Avon in Mapnik

[Dirk-Lüder Kreie]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

David Groom schrieb:
>> ----- Original Message ----- 
>> From: "David Groom" <reviews at pacific-rim.net>
>> To: "mike" <mike at bristolbeat.co.uk>; <talk at openstreetmap.org>
>> Sent: Tuesday, October 23, 2007 11:11 AM
>> Subject: Re: [OSM-talk] River Avon in Mapnik
>>
>>
>>
>> It depends on how you see things but it could be both a tagging and a 
>> rendering problem.
>>
>> The riverbank was originally derived from the PGS coastline import script, 
>> and the data then tidied up by me.
>>
>> The import script tagged the riverbanks as natural=coastline, and I left 
>> it as such for two reasons:
>>
>> 1) no clear definition of where a coastline ends and a river begins when 
>> it is a tidal river.
>>
>> 2) In Osmarender the rendering of coastline areas in my opinion is a lot 
>> less problematic than rendering of river areas, with a coastline all you 
>> have to do is ensure the "segments" point the right way, with water on the 
>> right,
> 
> I should have added a point (3)
> 
> 3)  To get an area waterway = riverbank rendered in mapnik it has to be a 
> closed area. This means drawing a "segment" across the river to join each 
> side of the riverbank.  I know this will render correctly, but it seems 
> "wrong" to me to mark a riverbank across the river when no such feature 
> exists in real life.  I guess it depends on whether you see the data we are 
> producing as being tagged to draw pretty maps in mapnik, or to actually 
> represent what exists in real life.
> 
> As I said earlier, I rather hope relations might solve the problem.

This should already work with a multipolygon relation, but I'm not sure
what osmarender does with the missing ways.

Alternatively tiles at home could (and should IMHO) expand the close-areas
script to include all water type areas.

- --

Dirk-Lüder "Deelkar" Kreie
Bremen - 53.0952°N 8.8652°E

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.7 (GNU/Linux)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org

iD8DBQFHHd3NFUbODdpRVDwRAh+yAJ99feUVtjengrC95WxWPKH2a4C63QCfaiMH
GudxvX8tHSpac8XSutHlOfs=
=cA3j
-----END PGP SIGNATURE-----