this will affect navigation routing result. asked 28 Aug '14, 17:32  klcaaron |
2 Answers:
A road is both ways unless you add oneway=yes to it (how you do this depends on the editor you use) answered 28 Aug '14, 17:40  EdLoach ♦ So adding tag 'oneway=no' to a highway is generally not required? (28 Aug '14, 21:22) NZGraham 2 No, oneway=no is generally not required, since a highway without the tag is assumed to be two-way. The sole exception would be highway=motorway_link. Since these are nearly always one-way, some data consumers make the assumption that all motorway_links are one-way. For any of the rare instances of a two-way motorway_link, it's a good idea to tag it oneway=no to explicitly indicate this. This isn't strictly necessary, but it doesn't cause any harm by explicitly tagging it. (28 Aug '14, 23:11) alester 2 Other exceptions might be where there's a oneway grid system in a city, but a particular street is two-way. It doesn't mean anything different to software consuming the data, but it's a hint to mappers that says "this street really is two-way". (28 Aug '14, 23:40) SomeoneElse ♦ 1 Note that if for some reason the road goes the opposite direction to the way itself and it is inadvisable to reverse the way for some reason (other tags that are directional or being part of direction dependant reltaion) you can use the value oneway=-1. (06 Oct '14, 23:51) InsertUser |
It is important that one way street are mapped correctly, routing won't work correctly if you don't. Roads are two-way by default (unset) just set them to the correct one way if needed, just check the arrows point the right way. Turn restrictions, for example "no right turn", also need care to get right as they apply to a pair of roads at the junction, and they can be a little more difficult to get correct. You can check them, after a while, with OSRM to see if the work in the way you expected. see https://help.openstreetmap.org/questions/32420/turn-restrictions-and-routing-engines answered 28 Aug '14, 23:16  andy mackey edited 28 Aug '14, 23:26 |
-1: Please Google "osm one way" and find https://wiki.openstreetmap.org/wiki/Key:oneway.
that -1 seems kind of harsh. this site is a place for people to ask questions--even basic ones--about OSM. if we can be helpful and welcoming here, hopefully they'll continue to contribute!