level at which natural=peak and natural=mountain_range will render

A week ago I was walking on a rail trail with elevations from 350 m asl to 600 asl.


Around me at all times were snow topped hills with elevations from 700 m asl to over 2,000 m asl.

Most of these peaks are above 900 m asl.

Only a small minority of peaks are named.

One range of hills extends over 40 km with many other ranges in the vicinity.

The “normal” browser display (https://www.openstreetmap.org/#map=xx) appears to shows hills as follows:
level 10 - nothing
level 11 - a “peak” for all named peaks (but no details)
level 12 - a “peak” for all peaks
level 13 - a “peak” for all peaks with name (if any) and elevation

At those levels I was not able to centre the map on my location and see the peaks.

The names of mountain ranges did NOT display at any level.

My proposal

level 8 - display peaks above, say, 2,000 m
level 9 - display peaks above, say, 1,500 m
level 10 - display peaks above, say, 1,000 m
level 10 - display names (if any) for peaks above 2,000
level 11 - display peaks above, say, 500 m
level 11 - display names (if any) and elevations for peaks above 1,500
level 12 - display peaks above, say, 300 m
level 12 - display names (if any) and elevations for peaks above 1,000

What you’re suggesting doesn’t sound too difficult to implement - it’s just using existing tags that the Carto mml / mss code either already sees or can easily see. Perhaps try making a copy of the stylesheet, changing it to work as you suggest and making a pull request based on that? There’s information at https://github.com/gravitystorm/openstreetmap-carto about how to do that, and a while ago I wrote
https://www.openstreetmap.org/user/SomeoneElse/diary/43041 which might also be useful.

You might also find https://www.openstreetmap.org/user/SomeoneElse/diary/391170 interesting (especially the comments). That explains how names and prominence are used at https://map.atownsend.org.uk , which tries to show “important peaks first”. Prominence is likely to become an important factor if you try and display peaks in the Himalayas at zoom level 8 (imagine e.g. https://www.openstreetmap.org/#map=8/35.641/76.608 - try zooming in and out).

@SomeoneElse, thank you for such a prompt reply.

**Stylesheet: **

I have looked at the two references you provided. For me, having been editing for almost 10 years, you introduce so many new terms and processes that I fear at my age (79 next birthday) I will not find the time to begin to experiment let alone master them.

I look on this as a quality of information issue for OSM as a whole and not just a personal issue for me, much as I would like to delve into it.

Himalayas versus Southern Alps foothills (my example)

Your point is partly made with respect to the Himalayas. Nothing shows at level 10 and so on as below. At level 11 a number show. I would think it would be more than helpful to readers that a sense of greatness appears at quite low levels.

In my example there were at around 200 peaks at 900 m asl or more. At present the browser only shows a few of them and then when almost on top of them.

I raised a specific question and I think your suggestion is heading towards a more general solution. That is good. Carrying on in that mode the solution as to the level at which peaks are displayed might be relative to the number and height of peaks for a country / region. As you say they are already seen or can easily be seen by existing code. At display time, or predetermined but changeable, the heights and levels for display is calculated.

For England (all regions) this might be everything higher than 100 m asl (not very many?!) from level 6. For Scotland (one region) it might be higher than 1,000 m asl at level 6 and so on. For Wales possibly a similar result for Scotland. For west Canada, west USA might have quite high peaks only at level 7 and increasing as the levels increase. And for the rest of those two countries the height at level 6 might be much lower.

For Aotearoa-New Zealand (my example) only those over 3,000 m asl are shown at level 6 and so on down to the schema I noted in my original submission.

My question

Where to from here?