I am the stock answer is tag for what is there, not for what a particular renderer happens to display. Even if the default, standard, or “reference” renderer people refer to is the one at https://www.openstreetmap.org/
You are correct that it is not being displayed. And looking at the nearby areas that lack may be confusing. Why would a road have a bridge over nothing? Why is there a curved linear area going through that development? Etc.?
It might be worth submitting a bug report to the people maintaining the OSM Carto rendering style though I suspect they will reject it.
The Standard rendering used to show railway=abandoned, but some zealous rail mappers kept using this tag even when every trace of the former railway had been obliterated (e.g. a railway=abandoned going through a mall). IIRC, a decision was made to no longer render this feature because it wasn’t being used consistently and was basically being abused in order to get historical railways to render (ie. tagging for the renderer).
If the railway=abandoned is suppressing the rendering of an on-the-ground feature, it might be reasonable for me to break with the documentation and tag an otherwise empty line with cutting=yes? (ie, not accompanying a highway or railway)
I guess I’m then tagging for the renderer myself, but it seems the anomaly is the railway=abandoned tag which is suppressing other, more obviously useful features.
A way with just cutting=yes wouldn’t be rendered on the Standard rendering either, so it isn’t really that railway=abandoned is suppressing it. AFAIK, cutting=yes isn’t currently rendered on the Standard rendering at all.
I would just tag it with railway=abandoned and cutting=yes, if that’s what’s on-the-ground. It would at least be rendered as an abandoned railway on OpenRailwayMap, and the data would be correct for any data consumers that use that kind of information.
That’s one more spur for me to log a request with the developers that not every abandoned:* object be suppressed. Sometimes it makes sense (eg, a ‘shop’ that isn’t really a shop) but sometimes, to me, it really doesn’t (eg, an abandoned quarry that’s still a great big hole in the ground)
Personally, cases like that sound like a good time to use abandoned=yes rather than the abandoned: prefix. While no longer in use, it’s definitely still a quarry until someone comes along and fills it in, so landuse=quarry makes sense.
There have been extensive discussions with the OSM Carto developers about that sort of thing, and I think they’ve made their view fairly clear - they don’t see the value of rendering e.g. abandoned railways, even when the scar on the landscape is pretty large. Other maps will certainly show “ex-features” when there’s likely still something on the ground (even if not usable for the original purpose).
The thing is I’m not really trying to map an abandoned railway (misleading post title perhaps), but rather the physical cutting - I think the map can be agnostic about how it got there.
So perhaps any request to the developers should be that cutting=yes (or maybe man_made=cutting) renders always, whether with or without a road/railway?
But I may be picking up a hint in SomeoneElse’s post that this is a long-settled issue not worth raking over again. If so, is it easy enough - for edification only - to summarise why it isn’t considered a breach of the on-the-ground rule that some major physical features don’t render?
Looking at things from the perspective of the style developers, they do need the freedom to decide what to include and what not to include. The problem with an “everything louder than everything else” style that shows absolutely everything is that it’d look pretty horrible visiually. There are only a limited number of variables that you’ve got to make things look different to other things. and rendering more types of features makes things more difficult.
Edit: Actually one thing that perhaps is worth mentioning is that OSM used to have a “show everything” style called “Osmarender”. It was lampooned somewhat for not being pretty, but did make an attempt to show everything. It went away as a global style because the infrastructure behind it went away.
The disussions have generally been separate but parallel. Most discussions about lifecycle tags (“abandoned:” etc.) have been on the tagging list https://lists.openstreetmap.org/listinfo/tagging I think; I don’t remember a proposal to render “abandoned:” objects generally in eith OSM Carto (or any other map style TBH).
It was railways that had those most discussion in OSM Carto’s github because (a) disused and abandoned railways used to be rendered there, (b) there is a clear “fanbase” of ex-rail trail mappers and cyclists in OSM and (c) it’s a much easier argument to make for “please render where you can see that a railway went here” rather than “please render that this used to be a Blockbuster and is now a fish and chip shop”.
I believe that the concept of general lifecycle tagging (e.g. “abandoned:foo=bar”) came after the use of tags such as “railway=abandoned”.
OSM has always separated “what gets mapped” from “what gets rendered”, and from the very earliest days there have been different renderings (showing different things) based on OSM data. In that sense there have never been tags “not designed to be rendered” - someone, somewhere is probably interested in everything.
There has been discussion about whether it makes sense to map something that’s not there any more (a building that has been demolished, for example). Generally, most people agree that OSM isn’t really the place for that, and https://www.openhistoricalmap.org was created to fill that gap. Where it gets complicated is whether it’s useful to say “there is an abandoned railway here”. Someone who gets palpitations if they go more than a couple of miles from a Pret a Manger might say “there was a railway here, but there isn’t any more, so don’t map it”. Someone else who uses features such as this for orientation (or if they’ve been turned into a cycle route, travel) would definitely argue in favour of mapping them.
People can choose what (if any) “disused” stuff to render. I’ve chosen to show a few - for example a former phone box that now contains a library, tourist information or defibrillator gets rendered as “a former phone box with something in it”.
And yes, I was linking to the map legend earlier, as an example of how disused, abandoned and dismantled / razed former railways are shown, and also under construction and proposed ones. As an example on the main map, the area around J29a of the M1 has quite a few - https://map.atownsend.org.uk/maps/map/map.html#zoom=14&lat=53.229&lon=-1.32948 - you can see the proposed north-south route for HS2, the east-west route of the LDECR and to the west the north-south route of the old Great Central.
All of this, especially that abandoned railways in particular seem to have led to some community trauma (possibly still being processed!), leads me to conclude that:
it would be useful for man_made=cutting to have a wiki page (it’s already got a handful of UK uses, though I can’t work out how to get overpass turbo to give me a count rather than a list)
it would be great if it rendered on OSM Carto just as man_made=embankment does now. Currently these are inconsistent: even where not also tagged abandoned: or disused: , man_made=cutting doesn’t render, whereas man_made=embankment does.
That way we can avoid the but-is-it-really-a-railway question altogether, and still map visible, on-the-ground features that are useful to have on the map.