[OSM-talk] Funny Mapnik rendering of lakes

Jon Burgess jburgess777 at googlemail.com
Mon Aug 13 22:52:25 BST 2007

On Mon, 2007-08-13 at 22:32 +0100, Dermot McNally wrote:
> On 13/08/07, Jon Burgess <jburgess777 at googlemail.com> wrote:
> > I found a minor problem with the data which meant the way overlapped
> > itself at 2 places. The points of overlap were very tiny but enough to
> > confuse the osm2pgsql code and result in the bad rendering. I have
> > attached 2 screenshots showing the problem data in JOSM.
> That makes sense. This lake was traced with the excellent lakewalker.
> I usually do a manual check of the banks to look for stuff like this,
> but I can't actually recall doing it in this instance. I'll know what
> to check next time I see this in Mapnik.

It would be tricky to spot this manually. Maybe we should see if we can
prevent lakewalker from generating overlapping segments.

Also, maybe the validator plugin could flag a warning if 2 segments in a
way overlap. 


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