On Thursday 28 August 2014, Peter Barth wrote: > Hi all, > > I created a new challenge for MapRoulette: "Fix waterway direction". > > As the waterway's direction in OSM denotes the direction of the > water's flow, I started to compare them to SRTM. This leads to more > than 1 million wrong directions for Europe only. Many times SRTM is > right, however, due to data errors, not every time. That's why I > created this challenge. > > [...]
Great to see the waterways are getting some attention. Does this only analyze SRTM elevations at start and end point or are the surrounding waterways considered? If a waterway meets another waterway at one side but is unconnected at the other for example this is usually a strong indicator for the direction independent of the elevations data (which is only helpful usually in mountain areas). In terms of usability it would of course be good if you could see the direction in MapRoulette so you can verify the data without actually loading it in the editor. -- Christoph Hormann http://www.imagico.de/ _______________________________________________ talk mailing list talk@openstreetmap.org https://lists.openstreetmap.org/listinfo/talk
