[OSM-dev] Coastline generalization tool and data

[Christoph Hormann]

Hello everyone,

some time ago i introduced a technique to generalize OSM coastline data 
for better readable map rendering [1] on talk-de and i now release the 
tool used for this [2] as well as a set of generalized coastline files 
for zoom levels 1 to 8 [3].  There is also a demo map [4] - this uses a 
slightly different coastline than the one for download (in particular 
Antarctica data is replaced by a different source).

Feedback on both the tool and the files is welcome.  It would be 
interesting to see how use of this would look like in the standard 
mapnik rendering, especially how much mismatch the moving of the 
coastline during generalization causes and how troublesome this is when 
viewing the map.

You might notice various strange forms in the coastline at some places, 
most of them are caused by features being tagged as coastline which in 
fact should probably not be.  I put up a wiki page [5] to collect these 
problems.  If you find more or fix them feel free to edit that.

[1] http://www.imagico.de/map/coastline_en.php
[2] http://www.imagico.de/coastline_gen/index.php
[3] http://www.imagico.de/map/coastline_download_en.php
[4] http://www.imagico.de/map/map_en.php
[5] 
http://wiki.openstreetmap.org/wiki/User:Imagico/coastline_problems_for_generalization


Greetings,

-- 
Christoph Hormann
http://www.imagico.de/