Request adding support for different train protection system types

[c933103]

• CTCS:
  https://taginfo.openstreetmap.org/keys/railway%3Actcs
  A Chinese version train protection system
• Radio: https://taginfo.openstreetmap.org/keys/railway%3Aradio
• ATC: https://taginfo.openstreetmap.org/keys/railway%3Aatc#overview
• CBTC:
  https://taginfo.openstreetmap.org/keys/railway%3Acbtc#overview

[bjoernma]

Was also a bit thinking of how to actually do it. As it gets very much different systems, it would be nice to have an recallable, unbiased order.

Possible differentiations which I see:

• random (how to avoid to similar colors?)
• Sort by alphabet (but what to do with transcriptions, or just based on english names?)
• Sort by age (would potentially have new systems which will last longer in similar colors/styles)
• Sort by behaviour or transmission mode (pointlike/linelike/ // mechanical (Fahrsperre)/electrical (crocodiles?)/balises/radio/... transmission
• Sort by possible max-speed, else random (how to avoid to similar colors?)
• Sort by km of railroads/number of countries which use this with this system (easily outdated...)

How to deal with already outdated systems / systems that will reach EOL in a few years? (Iwould like to use them as well in the system as some years is enough time)

Some of those properties could also be translated in non-color information such as line thickness or hatching.
Maybe near-EOL/EOL systems with dotted lines? But I would definitely omit possibly occuring disused/abandoned tags for it, would get to complicated...
Maybe systems in construction with dashed lines /
Maybe only planned systems in dash-dot-like lines?

What do you all think about it?

[xephos1one]

Theoretically all of https://wiki.openstreetmap.org/wiki/OpenRailwayMap/Tagging#Train_protection_systems should be supported.
Just to get started the biggest train protection systems should be added first like PTC (e.g. USA) that could easily be implemented similar to PZB and CTCS (e.g. China) that's similar to ETCS just with a few more options.

Radio: https://taginfo.openstreetmap.org/keys/railway%3Aradio

Radio would be wrong in this context because that isn't a train protection system.

random (how to avoid to similar colors?)

The color is the biggest question but there are enough colors for all systems.
https://openinframap.org/ shows that it's possible by displaying many different voltages with a reasonable color difference.

Sort by alphabet (but what to do with transcriptions, or just based on english names?)
Sort by age (would potentially have new systems which will last longer in similar colors/styles)
Sort by behaviour or transmission mode (pointlike/linelike/ // mechanical (Fahrsperre)/electrical (crocodiles?)/balises/radio/... transmission
Sort by possible max-speed, else random (how to avoid to similar colors?)
Sort by km of railroads/number of countries which use this with this system (easily outdated...)

These are questions for the other repo but alphabetical would be the best choice.

How to deal with already outdated systems / systems that will reach EOL in a few years? (Iwould like to use them as well in the system as some years is enough time)

Outdated systems should be removed from being rendered but systems that are near EOL but currently still in active use should be rendered just like active ones.

Maybe systems in construction with dashed lines

That's one way, the other is by using lighter colours like what is currently being used with ETCS, but the latter removes many colours that could be used for rendering additional train protection systems.

[JonathanBittner]

I'd like to see some of the US systems added even if they have to share colors with some of the European systems. The US is somewhat complicated, however, with three or more flavors of Positive Train Control (ACSES II [Amtrak, NYC-area commuter lines], I-ETMS [freight network], ITCS [single Amtrak line in Michigan]) one area (Maryland) with two PTC systems overlaid, legacy Automatic Train Control cab signaling that can also be combined with PTC (optional with I-ETMS, required [I think] with ASCES II), plus some Automatic Train Stop (inductive) some of which is standalone, some being phased out, and some combined with PTC. I think the line with Ansaldo ASES was upgraded to ACSES II.

Might be a good idea to pick one color for US PTC (could be shared with ETCS) and have the line labeled with the appropriate systems and addons, Automatic train stop [w/o PTC could share the color with PZB, perhaps with a notation for inductive vs mechanical (subways). Likewise areas without PTC but with Cab Signalling/Automatic Train Control could share the color with ATB.

Add a color [purple?] for CBTC and automated operation.

[DerDakon]

When sharing colours I would suggest to reuse them for somewhat similar systems, i.e. use reddish colors for systems that allow continuous influence while yellow is something that only has influence on a specific position.

My personal preference would be to only reuse blue for such systems that are actually somewhat the same than ETCS (like one Chinese system) as it is also used somewhat worldwide. Using purple as an alternative color for a different, but similar systems sounds like a good idea to me.

[xephos1one]

@DerDakon I don't know if sharing colours would be the best idea as it makes it indistinguishable when used next to each other like in Ethiopia where CTCS is used on the Ethio­-Djibouti and ETCS on the Awash­-Weldiya line.
Except it's intended to equate these systems completely. If that's the case you'd have to decide which systems should be equated - not only those similar to ETCS.

[DerDakon]

Good point.

[c933103]

What about using something like HSV color system for different types? Like each individual types of signal system or train protection system (European, Chinese, etc.) got their different hue, then the color brightness increase as the system level increase aka being closer to fully automated.

[STemplar]

Aside from line colors, could differetnt line type be implemented?

Like in the netherlands for ATB_eg and ATB_vv a continuous linetype and for ATB_ng a dashdot linetype?

[JonathanBittner]

I think it would be easier to do text labels or a slight color variation. Leave dashing for lines under construction.

[DerDakon]

Different casing or so is a nightmare as you can see by zooming in and out around here: https://www.openrailwaymap.org/?style=standard&lat=48.68620084610073&lon=9.321191310882568&zoom=15

In case there are 2 tracks the casings overlap so the line basically looks like solid color.

[davide84]

Recently the French systems, the Italian system and the american PTC have been added to the render.
I think a compromise regarding colors could be to consider each continent as independent, allowing identical or similar colors to be reused; the legend would then group items by continent (NAm - SAm - Europe - Africa - Asia) removing any ambiguity.
This way we could likely just stay with solid lines, as it is now, and the color discussions would happen on a regional scale.

As the only intercontinental coordination, at the moment I like that ETCS is blue and ATP is red, so in principle when zooming out each continent will have a clearly dominant color. This happened more or less by chance, but it could be considered as an official strategy when implementing the chinese CTCS (green?).

[LaoshuBaby]

Currently have more than 20000 elements using CTCS system in OSM, what about render this in a new color, like the way we render ETCS?

[Nakaner]

Is CTCS just ETCS with a different brand? If not, I would like to ask you to find an unsed color (preferred) or to use a color of system not used in nearby countries.

[davide84]

To my knowledge CTCS is to some extent based (at least, conceptually) on ETCS but it's not compatible and its development is independent.

ETCS is rendered as blue, the ATP in USA as red/magenta; this was done to suggest orange or green as most distinguishable colors in case CTCS rendering is implemented. I would not worry about other European colors, there won't be any overlap and the continent is planned to become mostly ETCS in one decade. There is a little bit of green in South Korea, though (TVM???).

I would say there's another issue regarding CTCS: many lines are rendered, and therefore tagged, as ETCS. Should they be moved to CTCS or is that another signalling variant?

@LaoshuBaby are you just proposing a feature or would you like to submit a PR?

[davide84]

Local test, CTCS in green, ETCS in blue:

[LaoshuBaby]

Is CTCS just ETCS with a different brand?

CTCS and ETCS are similar, but not the same. For specific explanations, please refer to the explanation in https://www.openstreetmap.org/changeset/129927242 (it is in French, you may need a translation tool)

I would say there's another issue regarding CTCS: many lines are rendered, and therefore tagged, as ETCS. Should they be moved to CTCS or is that another signalling variant?

Yes, as you said, some of the ETCS shown in your figure above should be marked as CTCS (most of them were batch edited by the mapper of the above OSM changeset, but the China community has not had time to fix them yet), the discussion can be found at https:// t.me/OpenRailwayMap/19/812 (in Chinese)
For example, the high-speed railway from Beijing to Shanghai in the picture is CTCS-3 https://en.wikipedia.org/wiki/Beijing%E2%80%93Shanghai_high-speed_railway

ETCS is rendered as blue, the ATP in USA as red/magenta; this was done to suggest orange or green as most distinguishable colors in case CTCS rendering is implemented. I would not worry about other European colors, there won't be any overlap and the continent is planned to become mostly ETCS in one decade. There is a little bit of green in South Korea, though (TVM???).

As for me, I prefer to choose red color for CTCS (whether it is lighter or darker, such as "[TieShuiHong, meaning'red like molten iron')](http://zhongguose.com /#tieshuihong)"), but if maintainers has other color suggestions, I will give priority to the maintainers' suggestion

@LaoshuBaby are you just proposing a feature or would you like to submit a PR?

I will try to propose a PR, but if there is any error in my code, just treat it as if I just proposed a feature.

[davide84]

I had some time this morning and I opened a PR:
#115

I think we can continue the discussion there to find a color.

[davide84]

I mention again here my PR #118 which aims at adding once for all support for all train protection systems, and thereby solving this issue :)