Being unnecessarily asked for shoulders on slow trunk roads (e.g. in cities)

[peternewman]

You get asked for shoulders (as originally suggested in #2444) on roads with only 30mph in cities because they're also trunk roads.

The accepted speed limits

StreetComplete/app/src/main/java/de/westnordost/streetcomplete/quests/shoulder/AddShoulder.kt

Lines 33 to 34 in 9eb9a2e

	or maxspeed > 50
	or maxspeed ~ "([4-9][0-9]|1[0-9][0-9]) mph"

Incidentally, is the speed regex right here; 50 kmh is 31 mph, but you're only matching from 40mph up; with all the other maxspeed regex, there seems to be a much tighter coupling between units. I think you either want 3[1-9]| at the start or > 60.

Are overridden by the highway=trunk tagging:

StreetComplete/app/src/main/java/de/westnordost/streetcomplete/quests/shoulder/AddShoulder.kt

Line 25 in 9eb9a2e

highway = trunk

Ideally it wants to be:

speed>fast
or ((!speed or speed>fast) and (highway=trunk)

At least in the UK, you generally only get those slow speeds on major roads in cities, at which point you don't have the space for shoulders and I'm not sure what benefit they'd be at that speed versus "all lane running" and having more lanes when there isn't an accident.

How to Reproduce
Answer the quest for here (except I already have):
https://www.openstreetmap.org/way/279154275

Versions affected
SC 40-beta1

[matkoniecz]

https://overpass-turbo.eu/s/1fPV confirms that highway=trunk maxspeed=30 mph will have shoulders really rarely - and what tagged may be a mistake.

[westnordost]

A trunk is certainly a road where one (=data consumers) would expect a certain stage of infrastructure, but I am not familiar with the trunk tagging in Britain. In Germany, roads are usually not tagged trunk unless they are "a bit like motorways".

We can fix the filter for mph speeds. I'll let the filter start at 35 mph because anything between 30 and 35 is uncommon and 30 mph would still be too low.
I change the filter like this: !maxspeed and hw = trunk or maxspeed >= fast, i.e. the default assumption is that trunk maxspeed is "fast"

[peternewman]

A trunk is certainly a road where one (=data consumers) would expect a certain stage of infrastructure, but I am not familiar with the trunk tagging in Britain. In Germany, roads are usually not tagged trunk unless they are "a bit like motorways".

I think in the UK it's based on the importance aspect (i.e. A road/B road) which are mostly fast/major (except in city centres).

We can fix the filter for mph speeds. I'll let the filter start at 35 mph because anything between 30 and 35 is uncommon and 30 mph would still be too low. I change the filter like this: !maxspeed and hw = trunk or maxspeed >= fast, i.e. the default assumption is that trunk maxspeed is "fast"

Thanks, that makes sense.