> ----- Original Message ----- > From: Igor Brejc > To: David Groom > Cc: David Earl ; Artem Pavlenko ; talk Openstreetmap > Sent: Monday, February 11, 2008 4:04 PM > Subject: Re: [OSM-talk] Large Rivers in general, mapnik rendering in > Particular > > > David Groom wrote: > I'll edit the wiki. > > Could you put some visual examples, please? > > > Artem, what i had in mind is now shown on > http://wiki.openstreetmap.org/index.php/Relations/Proposed/Rivers > > David G > > > I'm a bit late in entering this discussion, but at the first glance I see > at least one problem with this proposal: representing tributaries > (http://en.wikipedia.org/wiki/Strahler_Stream_Order), which must be > treated separately, since their usually have their own names. Either you > would have to define an OSM way splitting the main river and the tributary > (which in a sense defeats the idea of this proposal) or you would let the > renderer assume that it can draw such a segment by itself (which can > sometimes be problematic, I suppose). > I'm not against letting renderers do their jobs, but I think we should not > presume that all devices will have CPUs powerful enough to provide > interactive maps by processing complex geometry algorithms. Drawing > something like this, for example: > http://en.wikipedia.org/wiki/Image:Mouths_of_amazon_geocover_1990.png :) >
Thats a good point. I'm reasonably happy with the proposal for defining large rivers as closed areas, as outlined in the proposal http://wiki.openstreetmap.org/index.php/Proposed_features/Large_rivers . The proposal at http://wiki.openstreetmap.org/index.php/Relations/Proposed/Rivers was an attempt to satisfy some peoples concerns about a"segment" being drawn across the river to close the area, but I think in practice it probably causes more problems than it solves. David > Igor > > > -- > http://igorbrejc.net _______________________________________________ talk mailing list [email protected] http://lists.openstreetmap.org/cgi-bin/mailman/listinfo/talk
