Streetcomplete: surface=stone cannot be answered in surface quest

[eikel]

Use case
This is a follow up to #2277. I saw that the OSM wiki has been updated and that it makes sense to explicitly set the surface of stepping stones. I wanted to answer the surface quest for stepping stones which are really some large stones lying in the water. But, the stone answer is missing.

Proposed Solution
Add surface=stone as answer to surface quest.

[matkoniecz]

Note that surface=stone remains undocumented at OSM Wiki and is fairly rare (https://taginfo.openstreetmap.org/tags/surface=stone ).

Though looking at https://taginfo.openstreetmap.org/keys/surface#values it seems the most popular unsupported viable value.

I would recommend checking how it is used (Overpass Turbo, ask others on tagging mailing list or elsewhere) and documenting it, before it is even considered. I think that StreetComplete should avoid introducing new values not documented at OSM Wiki.

See https://wiki.openstreetmap.org/wiki/Talk:Tag:ford%3Dstepping_stones

---

Also, it is fine to have some rare values unanswerable with SC. Not sure whatever "series of big stones" should be considered as common enough to include as an option.

[Atrate]

I have to say I've run into a similar issue, surface=stone would often have helped

[rhhsm]

I'd also often have liked to have "natural stone" as an option where I now choose to tag as "paving stones". However I think this should be proposed at OSM and only be adopted by SC when consensus is reached at OSM.

[matkoniecz]

I'd also often have liked to have "natural stone" as an option where I now choose to tag as "paving stones".

Note that surface=paving_stones includes quite wide variety, including paving made from actual stones (if cut into flat pieces, otherwise it is sett or unhewn_cobblestone, see https://wiki.openstreetmap.org/wiki/Tag:surface%3Dpaving_stones )

[westnordost]

How about this for surface=rock? (People on OSM Slack tell me that "rock" would be more fitting for natural rough surfaces while stone would be more fitting for smooth hewn rock.)

https://commons.wikimedia.org/wiki/File:Bare_Rock_Trail_Surface_at_Lake_Roland.jpg

[matkoniecz]

Seems fitting to me to some cases not covered by other values ( https://commons.wikimedia.org/wiki/File:Krywan.JPG https://commons.wikimedia.org/wiki/File:Krywan_podejscie.jpg ), though it is also not documented and not very popular so I would also at least create wiki page before adding it

https://taginfo.openstreetmap.org/tags/surface=rock#overview

[westnordost]

Loose rocks came up shortly on Slack too. In English, this would probably be scree (though difference to gravel is not entirely clear to me, maybe size of such loose rocks)

[westnordost]

Screenshot for image search for "scree":

[westnordost]

There is also bare_rock (absence of smaller rocks, surface like a slab), however I don't really want to go into that detail here. rock seems to be a good category

[matkoniecz]

Going by https://en.wikipedia.org/wiki/Scree and my low quality knowledge of English terms - maybe scree is rather for natural gravel/small rocks while gravel is rather for man made crushed rocks of smaller and more regular size?

[ArloJamesBarnes]

gravel is a size classification. scree is an origin classification (it's a flow of rocks eroded out of a body uphill by frost action or otherwise), although it has a size component since on the larger end it's talus. So you can have a gravel scree, a pea gravel scree, boulder talus, etc.

[matkoniecz]

Mailing list post posted.

[westnordost]

So, there are now some nice pictures for surface=rock. Question is, if it should also be possible to tag stone?

[matkoniecz]

I have feeling that surface=rock and surface=stone would become tags with de facto the same meaning, even if some mappers/communities would have some different ideas about differences (Like surface=dirt vs surface=earth or natural=wood vs landuse=forest and so on)

[westnordost]

"would become"?

[westnordost]

The comments on the mailing list and on #tagging on osm slack were pretty consistent

[matkoniecz]

"would become"?

I think that even if planned differences would be documented and described then in actual usage the tags would be used interchangeably.

(even relatively clear surface=compacted is often problematic for mappers)

The comments on the mailing list and on #tagging on osm slack were pretty consistent

I am not opposed to this tag, just not planning to spend time on documenting it (I felt that surface=rock makes sense and would be an useful, so I put effort into documenting it).