Trunk road ignored for foot or bike routing - best way to solve

[boothym]

Came across this tweet: https://twitter.com/thomasforth/status/1381702567126835201

And this example in the replies of how OSRM was seemingly ignoring the A75 trunk road for foot and bike routing from one side of town to the other: https://www.openstreetmap.org/directions?engine=fossgis_osrm_foot&route=54.90570%2C-5.01110%3B54.90420%2C-5.02350#map=16/54.9016/-5.0153 (GraphHopper routes along trunk roads)

I looked at the debug view and found that was indeed the case: http://map.project-osrm.org/debug/foot.html#17.26/54.90434/-5.01646

In case you are wondering what this road looks like: https://www.geograph.org.uk/photo/4929194 (perfectly suitable for foot/bike routing)

So my question is - what is the best way to solve this in OSM? Just add foot/bicycle=yes, sidewalk=both, separately mapped sidewalks or a combination of all three?

[danpat]

TBH, OSRM is wrong here. There are some default access rules defined at:

https://wiki.openstreetmap.org/wiki/OSM_tags_for_routing/Access_restrictions#United_Kingdom

which shows that in the UK, highway=trunk should be accessible to foot traffic by default.

[frodrigo]

A way to to it is using polygons, like driving_side or maxheight.

https://github.com/Project-OSRM/osrm-backend/tree/master/data

[boothym]

Sorry @frodrigo, I'm not sure what you mean?

[danpat]

What @frodrigo means is that we should probably build up a GeoJSON that captures all these regional access restriction defaults, and make the .lua files use them so that defaults can be modified regionally.

[tombay]

I logged #6701. I looked at https://wiki.openstreetmap.org/wiki/Key:motorroad
-- and https://wiki.openstreetmap.org/wiki/OSM_tags_for_routing/Access_restrictions.
Most of the countries that allow trunk access to bike and foot can be covered by two cases. -
1/ trunk and trunk_link is allowed &
2/ trunk and trunk_link allowed if motorroad is no or not defined. I think GBR falls into this category.
I put my attempt to cover these cases in the final note to that issue. It relies on geolocation data and covers 30 countries that meet the criteria.
e.g. osrm-extract -p /usr/local/share/osrm/profiles/foot.lua --location-dependent-data=.countries.geojson ...
A real solution would of course cover all the other scenarios but for me at least it allowed bike (and foot) trails for NZ without having to add tags to the osm data.
Ciao
Tombay

[frodrigo]

@tombay maybe you wan to contribute a PR to add this features and polygons to OSRM itself ?

[tombay]

I will look into it (PR thing). I thought someone else might check into if the idea works. By polygons I assume it would be providing the geojson as a file osrm-extract could read. (I.e. the data that comes from the geoson output). I am not sure what impact it does to the extraction process. What I did (I thought) was just add trunk to the potential result set. ⁣Get BlueMail for Android ​

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On 18 Sept 2023, 5:56 pm, at 5:56 pm, "Frédéric Rodrigo" ***@***.***> wrote: @tombay maybe you wan to contribute a PR to add this features and polygons to OSRM itself ? -- Reply to this email directly or view it on GitHub: #6008 (comment) You are receiving this because you were mentioned. Message ID: ***@***.***>

[github-actions]

This issue seems to be stale. It will be closed in 30 days if no further activity occurs.

[frodrigo]

This issue seems to be stale. It will be closed in 30 days if no further activity occurs.

The idea is still interesting.

[tombay]

I created a PR #6703 (Sep 2023) which addressed this issue. A subsequent PR (#6708) seemed to cause an issue with my PR and it is languishing. It does include a 3.6 mb geojson file which outlines the countries affected. I thought having to traverse this file for each way (and node ?) would be a no no so approached it via
--location-dependent-data data/trunk_allowed.geojson. (and the associated country list in lua file). Maybe there is another approach.
%-?