Maxspeed quest in Austria: Add "sign together with city_limit-sign"

[Nielkrokodil]

Use case Austria has different possibilities to set a maxspeed.

1. sign (applies only to the specific street)
2. zone-sign (applies until end of zone sign)
3. implicit value living street (applies till end of living street)
4. sign together with city_limit-sign (applies to whole city)

Right now, SC has no possibility to map number 4, but only 1-3.

When you click "it is in a zone" this is technically correct, but the shown traffic sign is wrong.

The Austria community discussed it and chose source:maxspeed=AT:city_limit30 and =AT:city_limit40. https://community.openstreetmap.org/t/vorschriftszeichen-fur-das-ganze-ortsgebiet/127045 https://wiki.openstreetmap.org/wiki/DE:Tag:source:maxspeed%3DAT:city_limit30 (usage will grow after we just reached consensus)

Proposed Solution Add the possibility to add number 4: "sign together with city_limit-sign"

[mcliquid]

Should the tagging take into account that there are very often exceptions such as "except L123" (street ref) or "except priority roads"?

[Nielkrokodil]

If a major road (L123) is exempt, it should be tagged with AT:urban. Only roads which have a maxspeed different than AT:urban because of this traffic_sign-combination should get tagged with this special value.

The wording of exception can be tagged directly at the traffic_sign (not with SC)

[westnordost]

Hm well, I don't know about that. Do you expect users of the app to go to the city limits to check whether there is such a sign? The quest is already disabled by default because it might be too much to ask of users to go to the next main road (=possibly the start of the 30kmh zone) or start of the road (to look for a sign).

Now, when going to the city limits is a requirement for mapping speed limits at all, might as well just delete the quest.

[westnordost]

Not to sound like a broken record, but maybe it is time StreetComplete only tagged the physical absence of a sign (maxspeed:signed?), the on-ground truth, then this wouldn't lead to unreasonable requirements for surveyors to map speed limit (signs) at all.

Only problem with that though is that maxspeed:signed is virtually unused so far.

[mnalis]

Not to sound like a broken record, but maybe it is time StreetComplete only tagged the physical absence of a sign (maxspeed:signed?), the on-ground truth,t hen this wouldn't lead to unreasonable requirements for surveyors to map speed limit (signs) at all.

Yeah, but some people are quite unhappy with tagging non-existence of things even where it makes much more sense (e.g. sidewalk=no), so I'm worried they'd be even more annoyed with maxspeed:signed=no) 🤷

Perhaps, making Maxspeed Overlay first (https://github.com/streetcomplete/StreetComplete/issues/4282) would help (both in allowing users to only tag things they are confident about instead of "forcing" them to spend much time, and in reducing people complaints about tagging no values)

[Nielkrokodil]

Do you expect users of the app to go to the city limits to check whether there is such a sign? The quest is already disabled by default because it might be too much to ask of users to go to the next main road (=possibly the start of the 30kmh zone) or start of the road (to look for a sign).

Now, when going to the city limits is a requirement for mapping speed limits at all, might as well just delete the quest.

Yes, I expect Austrian speed limit mappers to check (or know) the city_limit sign.

Unfortunately we have such complicated jurisdiction. You have to make this descision (disable or not disable the quest) regardless if you give the mapper option 4 or not. When you are in an Austrian urban zone (Ortsgebiet), you have to know if there is a sign at the city_limit sign or not, otherwise you can simply not tell the speed limit from the absence of a sign.

So if you feel, this Austrian speciality is too complex for SC-Users, then a permanent deactivation of the quest would be reasonable. I personally have not encountered lots of wrong-taggings in Austria, so I would trust the SC-users (after manually enabling the quest and reading the warnings) to do this right. I would not disable the quest.

[Nielkrokodil]

maybe it is time StreetComplete only tagged the physical absence of a sign (maxspeed:signed?),

I don't like this idea. It would be unclear when a sign is too far away to be counted as absent. One block of buildings? The next intersection? The OSM way? 100 meters?

Also, would the presence of a zone-sign mean the absence of a "sign"-sign? This would be very hard to understand.

[matkoniecz]

It would be unclear when a sign is too far away to be counted as absent. One block of buildings? The next intersection? The OSM way? 100 meters?

depends on traffic rules

for example in Poland zone traffic sign applies until it is cancelled by end zone sign

and regular speed limit sign applies until it is changed or cancelled by intersection

[westnordost]

That's a good point. Apart from what @matkoniecz wrote, I guess, the presence of a "zone" sign should still count as being "signed", but I agree that it's not that clear cut, e.g. certainly an example could be found where a village that declared a village-speed-limit at the city limit sign is actually smaller than some neighborhood with a 30-zone sign.

UI-wise, that wouldn't pose an issue, as the different options could be described in appropriate words, though.

But it goes to show that the usage of maxspeed:signed doesn't then actually solve that many problems (from the surveyor/StreetComplete point of view) - the surveyor is not relieved from checking at the beginning of the road / next major intersection.

So, this feature request is pretty relevant for #4282 because StreetComplete would need to correctly parse and offer this as a selection option in an overlay. For the quest, it would get somewhat (more) relevant if the quest would be asked again after X years. Right now, its absence doesn't do any real harm, IMO, as the quest is only asked when maxspeed information is missing altogether - it is quite trivial to do a swipe over an entire city and replace XX:urban with that city limit sign tagging with JOSM.

I'd accept a PR that adds an option like this, though, but it should be limited to states where city-wide speed limits (can) exist. This requires a little research beforehand, which should be added here in a new file named e.g. hasCitySpecificSpeedLimits.yml or similar. How this should be selectable in the form is up to discussion, but I guess the dialog that prompts additional information (urban or rural) when selecting "no speed limit sign at all" would be the right place for that.

[wolfbert]

We're just discussing speed limit tagging for Austria in https://wiki.openstreetmap.org/wiki/Austria/Geschwindigkeitsbegrenzungen. This is not finalized yet, but we're leaning towards

• maxspeed:type instead of source:maxspeed
• maxspeed:type always in combination with maxspeed
• the list of AT:* values according to the table in https://wiki.openstreetmap.org/wiki/Austria/Geschwindigkeitsbegrenzungen#Implizite_Beschränkung

it is quite trivial to do a swipe over an entire city and replace XX:urban with that city limit sign tagging with JOSM

I'm not familiar with SC, but I see quite a few tagging problems from either inexperienced users (or the app itself, e.g. maxspeed:type without maxspeed). We may go from AT:urban to areas of 30 sign and/or AT:zone30 before we end up with AT:city_limit40. It takes a lot to get this right (which is why it often isn't).

[Nielkrokodil]

but it should be limited to states where city-wide speed limits (can) exist. This requires a little research beforehand,

I asked Minh Nguyễn about the US. City wide speed limits exist there with two exceptions (Oregon, West Virginia).

[wolfbert]

Right now, its absence doesn't do any real harm, IMO, as the quest is only asked when maxspeed information is missing altogether - it is quite trivial to do a swipe over an entire city and replace XX:urban with that city limit sign tagging with JOSM.

Just re-read this. If I interpret correctly, mappers may be tempted to enter incorrect information.

In case city-wide limit 40 applies, what do you enter? 40 + AT:urban (50) is incorrect, and 40 + AT:zone40 can't even be detected as incorrect. It's not as trivial as just replacing AT:urban, as this may co-exist with AT:city_limit?? (and possibly AT:zone??). The only reliable way of fixing this is to re-survey. Therefore, adding this option is important.

[1ec5]

but it should be limited to states where city-wide speed limits (can) exist. This requires a little research beforehand,

I asked Minh Nguyễn about the US. City wide speed limits exist there with two exceptions (Oregon, West Virginia).

Hey that’s me! 😅 I must confess I don’t quite grok what this ticket is about, but it’s true that citywide speed limits are commonplace in many states.

I think this is well-known, because several American mappers have attempted to insert citywide speed limits into the default speed limit table on the wiki, only to get reverted because StreetComplete considers it out of scope.

In fairness, that way lies madness: one of three major municipal code publishers lists over 13,000 municipal ordinances related to speed limits. Not all of them apply citywide, some apply only to a particular street or neighborhood, and a great many are signposted on the spot.

This underscores both the fragmented nature of speed laws and the fact that, technically, every speed limit sign represents a speed zone. If you pass from one street to another that has the same speed limit, you may or may not encounter a speed limit sign until the next reassurance sign. This is, after all, one of the reasons why users and mappers value our coverage of speed limits.

There is an issue of practicality: many American cities and towns have such unruly boundaries that it would be quite unreasonable to expect a mapper to put down what they’re doing and make a beeline dash to the nearest city limit sign. maxspeed:signed=no is a great idea, but it begs the question of how immediately the street’s speed limit must be posted. This sign at the city limits is immediately followed by a sign overriding it for that street, but if you turn right just past the first sign, you’ll end up on some streets that don’t have their own signposted speed limits.

StreetComplete’s usage model isn’t a perfect fit for all kinds of speed limits. Field surveyors and armchair legal researchers will need to work in concert to obtain comprehensive speed limit data. As long as maxspeed:signed=no only means “too hard”, that could be a workable solution.

[wolfbert]

Let me try to recap. This issue started as a request for SC to provide a way to tag a city-wide speed-limit (that is not xx:urban), which might be limited to Austria (in case this creates problems elsewhere). This is to avoid incorrect data being entered. What's wrong with that?

Hm well, I don't know about that. Do you expect users of the app to go to the city limits to check whether there is such a sign? The quest is already disabled by default because it might be too much to ask of users to go to the next main road (=possibly the start of the 30kmh zone) or start of the road (to look for a sign).

Yes, this is what mappers have been doing since 2004. Local mappers know the speed limit in their village or town, and if they can't find out, they shouldn't tag it. There's street level imagery, too. There's no need at all for maxspeed:signed=no, which is true for every road, starting right behind the sign.

Mapping isn't a contest, it's about quality, not quantity. 10.000 "mappers" entering incorrect or irrelevant data the easy way aren't helping, they just create more work for the others.