Hi, On 4/3/20 19:45, Martin Chalifoux via Talk-ca wrote: > This morning I checked some large cities namely New-York, Paris, Amsterdam, > London, Berlin. Since OSM is best developed in Europe these capitals make > sense. I just checked Tokyo, Shangai, Seoul, Sydney to sample Asia. None of > them have this sidewalk mapping as separate ways.
There are pockets here and there in Europe as well. Mostly what happens is this: 1. Someone wants to make a cool pedestrian/wheelchair/schoolkid routing project 2. The person or team has limited programming capability or budget, and hence must attack the problem with a standard routing engine 3. Standard routing engines do not have the capability to infer a sidewalk network from appropriately tagged streets (i.e. even if the street has a tag that indicates there's sidewalks left and right, the routing engine will not generate individual edges and hence cannot do something like "follow left side of X road here, then cross there, then follow right side" or so 4. Hence, tons of sidewalks (and often also pseudo-ways across plazas) are entered into OSM, to "make the routing work". (5. often people will then find that the routing engine generates instructions like "follow unnamed footway for 1 mile" which leads them to copy the road's name onto the sidewalk geometry... to "make the routing work"). (6. In some countries a pedestrian is allowed to cross a street anywhere. Happily I haven't yet encountered people cris-crossing the streets with footway connections to "make the routing work" in these countries. If you're in a country where you are only allowed to cross at marked crossings then that is easier.) All this is a sad state of affairs; if we had routing engines that could work well with simple "sidewalk" tags (and also make standard assumptions about which road types in which countries would usually have sidewalks even if not explicitly tagged), then we could save ourselves a *lot* of separately mapped sidewalks that really do not add valuable information, and just serve as crutches for routing engines. Personally I am very much opposed to the separate mapping of sidewalks, though I recognize that unless we have routing engines that work without these crutches, I will have a hard time convincing people to stop doing that. Bye Frederik -- Frederik Ramm ## eMail frede...@remote.org ## N49°00'09" E008°23'33" _______________________________________________ Talk-ca mailing list Talk-ca@openstreetmap.org https://lists.openstreetmap.org/listinfo/talk-ca
