Unify railway rendering

[pnorman]

We currently have subtly different styles for many similar types of rail

preserved: rail: rail service:

light_rail and subway tram:

monorail:

miniature:

disused:

There are some others too.

This is too many similar renderings.

I think it makes sense to

• Unify light_rail, subway, tram, and monorail. light_rail, subway, tram are all very similarly rendered already, and the differences don't correspond to anything logical. monorail is rendered differently, but in purpose it's similar to the other types.

• Render preserved with the width and dash property of rail, but a lighter colour

I'm not sure what to do about miniature, it doesn't fit in with our style. Disused is also a problem.

[pnorman]

This is inhibiting a bunch of code reuse with #2869

[matthijsmelissen]

I agree we have too many renderings now.

I'm against unifying tram and subway, there is an important and clear distinction between both in many European cities. Even the arbitrary difference that we currently have is useful.

Unifying light_rail and subway makes sense.

[dieterdreist]

2017-09-29 11:33 GMT+02:00 Paul Norman notifications@github.com:

Unify light_rail, subway, tram, and monorail. light_rail, subway, tram are all very similarly rendered already, and the differences don't correspond to anything logical. monorail is rendered differently, but in purpose it's similar to the other types.

subways differ from trams and light rail by the requirement to not have any level crossings, controlled or uncontrolled. IMHO they merit a distinctive rendering. Trams are often running on the road (shared surface), IMHO this makes them particular as well.

[matthijsmelissen]

Example where they (should) contrast: https://www.openstreetmap.org/#map=17/51.94817/4.46594

[aceman444]

@math1985 light_rail seems very similar to tram in many places so why handle it differently to tram and unify with subway? It is more similar to tram than to subway. I agree with dieterdreist.

[pnorman]

Example where they (should) contrast: https://www.openstreetmap.org/#map=17/51.94817/4.46594

That's a good example of where we're failing. Based on standard conventions, the east-west line is more important than the north-south line, but the data says the reverse.

I guess we could try going from four distinct renderings to two for the various types of (mainly) dedicated passenger lines.

[matthijsmelissen]

light_rail seems very similar to tram in many places so why handle it differently to tram and unify with subway? It is more similar to tram than to subway. I agree with dieterdreist.

No. On a range from local transport to long-distance transport, the range is normally tram-subway-light rail-subway. At least for any given city/metropolitan area. Of course, the way we render them in terms of prominence should reflect that.

Both trams and trains can have level crossings (unlike subways), but that doesn't make trams and trains similar.

[kocio-pl]

A bit off-topic, but it might be useful here: there's a (still incomplete) list of all the subways in OSM.

[dieterdreist]

sent from a phone

On 30. Sep 2017, at 23:28, kocio-pl notifications@github.com wrote:

A bit off-topic, but it might be useful here: there's a list of all the subways in OSM.

the name is a bit misleading because these contain also light rail

[HolgerJeromin]

Monorail has a very special type of rail. This should be visible

Cc @nakaner

[aceman444]

@math1985 we were comparing physical appearance in real life and not some "distance factor" (we also do not distinguish long-distance buses from city local buses). There, tram, light_rail and rail do appear similar, they are on the ground and with level crossings. subway is different to all of them (unless it comes to the surface, as in some cities, but I haven't checked how that is to be mapped). I do not say to unify tram, light_rail and rail, but I oppose unifying lightrail and subway.

[matthijsmelissen]

@aceman444 However, we don't want to map things based on how they look like, but on what their purpose is (a map is not a vectorized aerial photo, as @gravitystorm likes to say).

[dieterdreist]

sent from a phone

On 4. Oct 2017, at 22:53, aceman444 notifications@github.com wrote:

. There, tram, light_rail and rail do appear similar, they are on the ground and with level crossings. subway is different to all of them

while subways can’t have level crossings, it doesn’t mean tram, light rail or rail have to have them (e.g. the tram in Stuttgart ran partly in underground tunnels since 1966). Elevated subways are not completely rare, I’ve not seen light rail with level crossing anywhere central (but it might exist).

[aceman444]

As light_rail is defined to be somewhere between tram and rail, and both do have level crossings, it is natural to expect light_rail may have them too. And indeed I know light_rails that all have level crossings.

[matkoniecz]

See unify rendering for railway=rail and railway=preserved #1785 and render railway=light_rail like railway=tram #1829

I proposed both and closed them due to lack of a clear support, but I still think that unifying at least light_rail and tram makes sense.

[matkoniecz]

separate style for disused rail, normal rail and rail service in my opinion makes a perfect sense and I would not change this.

I have a very limited experience with railway=miniature so I have no opinion here.

I think that separate styles for light rail, subway, tram and monorail are overkill.

Subway on the ground, light rail and tram may be really hard to distinguish and have almost exactly the same function. Monorail is a different technical solution, but is it really a reason to use a completely different style?

I'm not sure what to do about miniature, it doesn't fit in with our style

Agree 100%

Disused is also a problem.

Yes, meaning of these dots is not clear.

I'm against unifying tram and subway, there is an important and clear distinction between both in many European cities. Even the arbitrary difference that we currently have is useful.

Is there really a significant difference between tram in a long tunnel and subway or between subway on the ground level and tram?

There is already a separate rendering for railway in a tunnel.

subways differ from trams and light rail by the requirement to not have any level crossings, controlled or uncontrolled

We render level crossings.

Monorail has a very special type of rail. This should be visible

But why it should be visible? Is it really so crucial to show this? For example we are not showing gauge of railways (except railway=miniature) or specially rendering unusual bridges.

[printmaps]

Please avoid solid dark lines. This is a problem with light_rail and tram. Alternative rendering:

light_rail (similar to rail with green color):

tram (similar to miniature, do not render miniature anymore):

[matkoniecz]

Please avoid solid dark lines. This is a problem with light_rail and tram.

Why it is a problem?

[Tomasz-W]

related to #1877

[Tomasz-W]

We surely have too many of railway renderings, and some of them are blocking good changes. E.g. https://github.com/gravitystorm/openstreetmap-carto/issues/640 would be similar to current railway=miniature rendering and https://github.com/gravitystorm/openstreetmap-carto/pull/3553 would be similar to current railway=disused rendering.

My proposition is to:

• unify rail and rail_service
• use current rail_service for disused
• unify preserved, miniature and narrow_gauge (they all have often tourist attraction character)

[matkoniecz]

narrow_gauge may be still in industrial use in some places (maybe many places outside Europe?)

[kocio-pl]

Rail service can be very strong when there's a lot of them and sometimes it would be hard to see the main lines. That's why service railways are lighter and disappear on z12. Example:

https://www.openstreetmap.org/#map=14/52.2143/20.9291

[mboeringa]

narrow_gauge may be still in industrial use in some places (maybe many places outside Europe?)

They also still serve "light_rail" type local and regional transportation in some countries, they are not necessarily touristic only: https://en.wikipedia.org/wiki/Narrow-gauge_railway

[Tomasz-W]

Ok, I see. I can propose another option to consider:

• unify railand preserved (in my opinion, 'preserved state' of a railway is not an enough reason for giving it special dedicated rendering, especially if we have too much of them)
• move current preservedrendering for disused

[Tomasz-W]

@vholten Can you prepare test renderings for my proposition above as it's closely related to borders colour topic?

Changing borders colour to more greyish without changing railway=disused rendering may end very bad in places like here: https://www.openstreetmap.org/#map=19/52.37750/16.90308 https://www.openstreetmap.org/#map=19/52.37546/16.83968

[Tomasz-W]

Here is another example of collision of current railway and borders rendering schemes:

https://www.openstreetmap.org/#map=19/52.37906/16.94670 (two disused tram lines with district boundary between them)

Borders violet or gray, it's colliding with each other anyway.