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Comment by plopz | Hacker News Reader

Do you know of any tile service offering colored, shaded elevation reliefs? I've been trying to find something for our meteorologists to use and the best I've found is https://maps-for-free.com

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I recently wrote a guide (https://blog.mapbox.com/styling-mapbox-terrain-rgb-c75d1cd71...) about extruding the contour lines within the Mapbox Terrain vector tiles (https://www.mapbox.com/vector-tiles/mapbox-terrain/#contour) that could be helpful to you as soon as I update it to match our recently re-released Studio product.

Check out https://www.mapbox.com/help/access-elevation-data/ for more background and let us know @Mapbox if you have questions!

Note - I work at Mapbox

> Do you know of any tile service offering colored, shaded elevation reliefs?

Does that imply variation in coloration based on elevation? (Just making sure I understand your question.) We have limited support for basic hillshading and are actively looking into contour lines. Coloration for various elevations is something we do not currently offer (nor am I aware of any other providers), but it is something we would be willing to investigate.

Depending on what precise application you need, this may be possible one the web using our normal vector maps and contour lines.

Yes, color for elevation and shading for slope.

Another use case that I've been searching for is a tile set not of images, but of just elevation data. So that I could implement something similar to google earth's lat/lng/elevation info wherever your mouse cursor is.

You don't need a web service for that. The data is free, search for "SRTM" and download the continents you need.

https://en.wikipedia.org/wiki/Shuttle_Radar_Topography_Missi...

Sure but I have no expertise on how to take those files and turn them into a tiles that correspond with the same basemap image tiles. Also ideally the service would incorporate more than just SRTM, including for example the USGS high res DEM where available.

Same boat, but does this help at all? https://wiki.openstreetmap.org/wiki/SRTM

This is just what the comments you replied to were discussing

You’re right, but seems to include implementations the user may be able to leverage? Specifically "In Use" and "Data in OSM format (XML)"

> how to take those files and turn them into a tiles that correspond with the same basemap image tiles.

The format is very simple to make sense of. Each file is an array of 16 bit integer values in meters, and it maps 1x1 degrees areas. Each file contains 1201x1201 or 3601x3601 samples depending on resolution. The first/last row/columns of adjacent files overlap that’s why non-round numbers.

Both SRTM and tiles use Mercator projection, i.e. mapping them together is very simple, too. In the embedded software I’ve developed, I’ve layered SRTM-derived data on top of OSM tiles, worked quite well and wasn’t too hard to implement. Even though due to very slow target hardware (500MHz CPU, 256MB RAM, slow flash storage), I had to invent more optimized format for SRTM data (dense array of 32x32 tiles taking exactly 2kb/each, aligned by disk sector), and implement an offline converter.

> including for example the USGS high res DEM where available

I haven’t personally compared them, but before picking SRTM for that embedded GIS project I’ve read about them, and concluded SRTM is more reliable. Also the resolution is more or less the same, SRTM offers 25m horizontal resolution, that’s pretty high, IMO.

Have you evaluated SRTM (or some patched up derivative) for your latter use case?

Yeah, its unfortunately missing a lot of alaska. But the main problem is I have no idea how to reproject it into web-mercator and generate usable tiles from it.

https://github.com/andrewharvey/srtm-stylesheets might help

(Full disclose I'm the author)

This looks awesome. Using those scripts I think I could actually do this myself.

We don’t have a current offering, but if you want, please email me at luke@stadiamaps.com. We’re actively investigating ways to integrate more datasets (such as elevation) and we would be happy to learn more about what you need.

If we can’t offer something, we’ll at least be able to point you in the right direction!

Give http://services.imagico.de/relief.php?lang=en a try.

Which zoom levels do you need? What coverage?

Try Thunderforest - relief is one of their specialities.

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