User:Alv/Highway decision tree

From OpenStreetMap Wiki
Jump to: navigation, search

Work in progress

The Original tree

Before highway=path was conceived, this was the way to tag ways with the highway key. It's still mostly valid, and mostly does not contradict with newer ideas.

  1. Is it steps?
  2. Is it a signposted motorway?
  3. Is it a "proper" road which allows regular motor vehicles?
    • Yes: use country specific rules for choosing between trunk/primary/../residential. End.
    • No: Is it a driveway, a parking aisle, or something else that fits highway=service?
      • Yes: highway=service, possibly with service=*. End of algorithm.
      • No: next step.
  4. Is there a "public footpath" sign, or a Belgium-trafficsign-d11.svg sign (or similar)?
    • Yes: highway=footway. (Originally, if it had the "public footpath" sign, there was a recommendation to add foot=yes to differentiate it from permissive and other footpaths; now there's designation=public_footpath for that.)
      1. Does it somehow allow cyclists?
        • Yes: add bicycle=yes. End of algorithm.
        • No: End of algorithm.
    • No: next step.
  5. Is there a "public cycleway" sign or a Belgium-trafficsign-d10.svg or Belgium-trafficsign-d9 bicycle foot.svg or Belgium-trafficsign-d7.svg, or similar?
    • Yes: highway=cycleway.
      1. Was it Belgium-trafficsign-d7.svg?
        • No: add foot=yes. End of algorithm.
        • Yes: add foot=no. End of algorithm.
    • No: Next step.
  6. Is there a "public bridleway" sign, or Belgium-trafficsign-d13.svg or similar?
    • Yes: highway=bridleway
      1. Does local legislation, or other signs present, allow or ban cyclists or pedestrians on that way?
        • bicycle=no/yes and foot=no/yes accordingly. End of algorithm.
    • No: next step.
  7. There's still two traffic signs available: Does it have Belgium-trafficsign-C5-C7.svg, or "No motor vehicles"?
    • Yes: cyclists and pedestrians are still allowed (and probably horses, too). Signs didn't give an unambiguous answer, so you'll have to use heuristics. Jump to step 9 for these.
    • No: next step.
  8. Does it have Belgium-trafficsign-c3.svg or similar?
    • Yes: not even cyclists allowed, but pedestrians may use it, so it's a highway=footway. End of algorithm.
    • No: Seems there's no sign. Now newbies gonna get confused. Next step.
  9. Does it only lead to something tagged highway=steps?
    • Yes: it's de facto only usable for pedestrians; highway=footway. Add bicycle=yes if allowed.
    • No: next step.
  10. If it was Belgium-trafficsign-C5-C7.svg, Belgium-trafficsign-c3.svg or similar, but with an auxiliary sign effectively stating "driving to premises allowed":
    1. Does it lead to a (private) parking space somewhere (which means that there's likely some motorcar traffic on most days), it might well be a highway=service + service=driveway. If that is not the only destination, just split it where such use ends, and consider the next part separately. On the other hand, if there's hardly any such "destination" motor vehicle traffic (say, just one house), but lots of cyclists or pedestrians, footway or cycleway can be more fitting; just add motor_vehicle=private/destination. Jump to next step.
    2. Does it only lead a farm field or fields, or deep inside a forest just for timber harvesting? Are there signs of regular tractor use, i.e. small heaps of clay or wide tire ruts?
      Yes: it looks like it's mostly for (private) agricultural/forestry traffic only; highway=track, with foot+bicycle tags as fitting.
      No: it's usable as a through route, but might effectively be an unused detour.
      1. Is it mostly used by pedestrian/cyclist traffic as a through route, or just for strolling?
        Yes: use the next top-level step for a decision based on the physical looks of it.
        No: hardly ever used and not really a through route anywhere, or so bad condition that only tractors and atv's can use it; most likely a highway=track
  11. Did it allow horses?
    • No: apparently it's mainly for pedestrians and/or cyclists. Next step.
    • Yes: it might fit bridleway, but first: what does it look like?
      1. Mud, turf, sand, grass, soft, good for a gallop, hard for a city cyclist: it works like a bridleway, it looks like a bridleway; so tag highway=bridleway + foot=yes + bicycle=yes + surface=* + wheelchair=no. End.
      2. Compacted, paved, or otherwise "built for walking or vehicles": doesn't look like a bridleway, horse riders wouldn't prefer it, so next step.
  12. Would you call it a cycleway, or a footway? Do you ever see cyclists on it, or just local residents walking from their home to their car? Is there are more cycleway-like road/"path" next to it? It's not legally anything with a 1:1-relation to osm highway values, so you need to use local knowledge and local judgement; choose one of

After the algorithm is complete, you would then add any legal allowances given by "additional signs", or by land owner's right (i.e. , and add tags like surface, segregated, wheelchair, lit etc.

The traffic sign based tree

From the discussions around the then proposed highway=path, the decision tree would change somewaht. The first steps are the same as above.

  1. Is it steps?
  2. Is it a signposted motorway?
  3. Is it a "proper" road which allows regular motor vehicles?
    • Yes: use country specific rules for choosing between trunk/primary/../residential. End.
    • No: Is it a driveway, a parking aisle, or something else that fits highway=service?
      • Yes: highway=service, possibly with service=*. End of algorithm.
      • No: next step.
  4. Is there a "public footpath" sign, or a Belgium-trafficsign-d11.svg sign (or similar)?
    • Yes: highway=footway. Many consider this to imply foot=designated, i.e. that there is such traffic sign present. End, as some consider that no other modes can be allowed. End.
    • No: next step.
  5. Is there a Belgium-trafficsign-d7.svg or similar?
    • Yes: exclusive cycleway, highway=cycleway, foot=no if not considered implied. End.
    • No: next step.
  6. Is there a "public cycleway" sign or a Belgium-trafficsign-d10.svg or Belgium-trafficsign-d9 bicycle foot.svg or similar?
    • Yes: choose either of
    • No: next step
  7. Is there a "public bridleway" sign, or Belgium-trafficsign-d13.svg or similar?
    • Yes: highway=bridleway
      1. Does local legislation, or other signs present, allow or ban cyclists or pedestrians on that way?
        • bicycle=no/yes and foot=no/yes accordingly. End of algorithm.
    • No: next step.
  8. Does it have Belgium-trafficsign-C5-C7.svg, or "No motor vehicles", but with an auxiliary sign effectively allowing farm/forestry traffic, i.e. tractors and logging trucks?
    Yes: highway=track. access=agricultural or similar, as signposted. End.
    No: next step.
  9. Does it have Belgium-trafficsign-C5-C7.svg, or Belgium-trafficsign-c3.svg, or "No motor vehicles"?
    Yes: highway=path. End.
    No: next step.
  10. Apparently it has no signs. Are any motor vehicles still allowed (some countries don't consider mopeds or mofas motor vehicles in this context)?
    No. highway=path. End.
    Yes:
    1. Is it a forest walking trail, unsuitable for any regular vehicles regardless of it's width?
      Yes. highway=path. End. [1]
      No. Next question.
    2. Is it wide enough for a two tracked vehicle?
      No: highway=path. End. [2]
      Yes: highway=track End. [3]

[1] makes a forest trail use the same highway value as a signposted combined pedestrian/cyclist way (that is Belgium-trafficsign-d10.svg or similar). Compare with the next point:

[2] makes a distinction in the highway tag between signposted combined pedestrian/cyclist ways (that is Belgium-trafficsign-d10.svg) and ones that are Belgium-trafficsign-C5-C7.svg, but effectively identical.

[3] makes perfect de-facto combined pedestrian/cyclist ways appear as tracks.


Work in progress