OpenAndroMaps “green railway lines” are rendered as active railways in VTM

[troNpo]

When using the motoraider.xml theme with the VTM viewer, the greenways shown in OpenAndroMaps are rendered as if they were active railway tracks.
However, when using the official mapsforge maps, these same lines are not rendered as active.My understanding is that these greenways come from former or abandoned railway infrastructure, but OpenAndroMaps’ preprocessing/tag‑mapping seems to make VTM interpret them as active railways.My question is:
Is this behavior entirely dependent on OpenAndroMaps’ tag schema, or is it possible to correct it directly in the theme XML (motoraider.xml)?

[MotoUKRider]

Hello @troNpo , I help maintain these themes, so I'll give the answer as I see+understand it:

This is tagged as highway=track and railway=abandoned with a tracktype (ie: surface) of grade2. Looking at a section of this "track" suggests that the off-road (brown) styling I use is correct. It's a track that a reasonably sturdy vehicle can drive on - no rails evident.

OpenAndroMaps' tag-mapping does indeed have an entry not found in Mapsforge:
<osm-tag key="railway" value="abandoned" zoom-appear="14"/>

This is why you are seeing railway tracks - I would expect railway=abandoned to be an old railway track, rusty, hidden by grass/weeds etc and not something you could take a vehicle on.

The nearest I could find in Mapsforge is: <osm-tag key="railway" value="disused" zoom-appear="15"/>

[troNpo]

Thank you very much for your quick reply, I really appreciate it. I know your work well — in fact, this report comes from a VTM theme I’m developing based on Motorider.xml for OpenAndroMaps. With the information you provided, we’ve adjusted the rules and now have the behaviour we were aiming for on OpenAndroMaps. Thanks again for the clarification and your time.

[MotoUKRider]

@troNpo Glad to be of help! Thinking a bit more about this, it may be useful to write some additional words because there seems to be a couple of different "issues" at work here:

1. (Mis)Tagging of objects/ways in OpenStreetMap. If it's a railway then it can't (IMHO) be a grade2 surface. To the casual observer of a map, if you see railway tracks, you quite rightly assume that riding your bike/steam-roller over them isn't practical.

My thinking goes against the OSM tagging Wiki as they suggest disused for a railway track left to overgrow, but abandoned for one where the track has been removed - To me, they seem like the same thing. If I abandon something, I leave it where it is and let nature takes its course. I understand that some kind of record/visual is useful - perhaps historic would be a better tag.

A separate railway track rule, perhaps a softer grey shade, could be used if you need to see where the tracks were. We would also need to add <osm-tag key="railway" value="abandoned" zoom-appear="14"/> to the tag-mapping in Mapsforge so the next generated maps could use the rule.

2. Theme rules and their order - Much like the "whoever saves last wins" rule in shared file opening, earlier rules are overwritten by newer ones. A good example would be the "toll" layer which overlays a red-dash onto the existing road - this needs to be defined after the road itself because, as an overlay, it needs to sit on top.

Speaking from experience, looking at troublesome areas in OpenStreetMap, right-clicking and Querying the tags can save a lot of headaches when you're trying to style a map and can't work out why it isn't looking pretty.

[troNpo]

Thanks for the clarification. Based on your explanation, we separated railway=disused and railway=abandoned into independent rules in our VTM theme, instead of keeping them inside the main railway group. This prevents greenways from being rendered as active railway lines and produces a result closer to Mapsforge/OpenAndroMaps.

This small change fixes the rendering issue in VTM and aligns the theme with the expected behavior for former railway lines.

Here is the code we added:

<!-- Disused railways -->
<m k="railway" v="disused">
    <m zoom-min="13">
        <line cap="butt"
              stroke="#80999999" width="0.8"
              stipple="15" stipple-stroke="#E0FFFFFF" stipple-width="0.4"/>
    </m>
</m>


<!-- Abandoned railways -->
<m k="railway" v="abandoned">
    <m zoom-min="13">
        <line cap="butt"
              stroke="#80AAAAAA" width="0.8"
              stipple="3" stipple-stroke="#A0FFFFFF" stipple-width="0.4"/>
    </m>
</m>

[devemux86]

• Mapsforge tag mapping is here

• OpenAndroMaps tag mapping is here

If you think we should add more tags in Mapsforge, please suggest them.

[MotoUKRider]

@devemux86 I've been working with OpenAndroMap areas to apply this tweak to our themes, but we will need <osm-tag key="railway" value="abandoned" zoom-appear="14"/> (to match OAM) or <osm-tag key="railway" value="abandoned" zoom-appear="15"/> to match our existing/similar disused tag.

As it stands, any railway=abandoned entry is not currently visible in Mapsforge Map files. I've found a few old railway lines here in the UK which look OK with my changes, but the example from @troNpo with the "track/grade2" is a unique one and quite a nice find.

[devemux86]

<osm-tag key="railway" value="abandoned" zoom-appear="15"/> to match our existing/similar disused tag.

• Done with Map mapping: add railway=abandoned mapsforge#1802

It will be available in the next updated maps.