Bonjour James, sorry for the delay. About your example, I couldn't have shown it better!
The procedure I use ... - All features having a natural=water tag are dissolved together before creating a coastline feature. - The features having natural=water and water=intermittent tags are copied into another layer before being reintegrated after the creation of the coastline feature. Daniel -----Original Message----- From: James A. Treacy [mailto:[email protected]] Sent: September-08-11 13:59 To: Daniel Begin Cc: [email protected] Subject: Re: [Talk-ca] Using Canvec data to recreate or modify coastline features Daniel, I'd like to make this more concrete with an example. If you have canvec data that shows: llllllllllll this area is land -i-i-i-i-i-i-i-i way which is natural=water;water=intermittent iiiiiiiiiiii area with intermittent water -w-i-w-i-w-i-w-i boundary with 2 ways. One is natural=water and the other is natural=water;water=intermittent wwwwwwwwwwww this area is water is this what OSM should have? llllllllllll this area is land -c-i-c-i-c-i-c-i boundary with 2 ways. One is natural=coastline and the other is natural=water;water=intermittent iiiiiiiiiiii area with intermittent water -i-i-i-i-i-i-i-i way which is natural=water;water=intermittent wwwwwwwwwwww this area is water Obviously, the ways would be closed but I think this gives the idea. On Mon, Sep 05, 2011 at 09:37:11PM -0400, Daniel Begin wrote: > Hi all, > > Earlier today I was looking at coastline features modified to fit Canvec > data and I found a problem with the "conversion". I think all of those who > are converting coastline using Canvec data should be aware of the Canvec > water data model... > > In Canvec data you will find two types of water polygons (natural=water)... > > One type defines permanent water - an area that is always covered by the > water. > > - It is tagged natural=water > > One type defines intermittent water - an area that is occasionally, but not > always covered with water. > > - It has two tags. One is the standard natural=water tag, the other is > water=intermittent tag(1). > > > > The problem is that the coastline seems to be defined as the mean high water > level (MHWL) position(2). To create a coastline that meet the MHWL position > using Canvec, you must merge all natural=water polygon type before > converting it to coastline. > > > > JOSM provides a good tool to merge those polygons - join overlapping area > (Shift-J) > > > > > > Daniel > > > > > > > > 1 - http://wiki.openstreetmap.org/wiki/Proposed_features/Water_cover > > 2 - http://wiki.openstreetmap.org/wiki/Tag:natural%3Dcoastline and other > wiki discussions > > _______________________________________________ > Talk-ca mailing list > [email protected] > http://lists.openstreetmap.org/listinfo/talk-ca -- James (Jay) Treacy [email protected] _______________________________________________ Talk-ca mailing list [email protected] http://lists.openstreetmap.org/listinfo/talk-ca
