"Best" place to find free US elevation data?

I have a few hobby projects I’m working on… I’m planning on trying to create some realistic terrain on which I’ll be placing some architectural models.

I’ve found a few grayscale sources here and there, but nothing really good ad far as resolution goes. I figure that there may be free data we can get somewhere, possibly, but haven’t found it so far.

Topo lines are probably OK as long as they’re high enough resolution, too.

Any recommendations?

Hello,

It depends for which country/area, but here are some things I found over the years.

For the UK, if you have money or belong to an institution:

I’m assuming you will consider using GIS to process the data, there’s a number of REST servers to pull data off - I’m quite amazed what kind of datasets I found just adding “arcgis” or “gis” at the end of a search term - for example:

you can find various WMS/WFS services on places like

https://data.gov.uk

For the US you have this directory

Resolution was a little low so I didn’t get to see if there’s anything useful to be extracted here, but I keep this one as a back up for Europe:

And by far my favourite is, resolution can be low at times, but it’s easy to get, easy to work with and they have a lot of terrain:

Hope these help get you started - I usually convert the rasters to points and export them as a CSV to read back in GH and get a nice clean quad mesh out - they get pretty gigantic though, depends how many millions of points you’re willing to deal with, though I find it a more exciting way to heat my house with energy prices the way they are!

Good luck!

  • Sash
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Thanks! I’m looking for US data… amended my title.

I’ll check these out.

If you are looking for a more programmatic approach, the USGS has an ArcGis Rest Service for their 3DEP product which will give you a DEM tif. The highest level of resolution will vary by location, but some places are near 1m. The nice thing about this approach is you can control the size of the resulting mesh with an arbitrary boundary for your area of interest and a selected image resolution.

Heron has component called RESTTopo that will do just this in GH. Once you set the EarthAnchorPoint with the SetEAP component, just give it a boundary and select the 3DEP service from the component menu and you get back a DEM tif that you can plug in to the ImportTopo component to generate the mesh. If desired, you can also grab satellite imagery with the RESTRaster component which you can then map to the topo mesh with Human components.
20231116_3DEP Topo Import.gh (26.1 KB)

-Brian

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That is so cool, thanks for sharing in such detail @Brian_Washburn, is there a cost to this?

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It’s all free!

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Hi Brian - thanks so much for your help & resources!

I am following your instructions, but it appears that in the Import Topo panel, it’s looking for something on your C: drive :slight_smile:

image

I think the elevation data is capturing correctly:

image

thanks again.

Andrew

Hi @Andrew_Turner ,
That’s a default folder that populates in the component when I initially place the component on the canvas. Change it to one that makes sense for your machine and it should work.
-Brian

Thanks - I’m not sure how to change it, or if anything is supposed to be in the target folder.

Same question, possibly, for “Get REST Raster”, though I haven’t gotten that far yet.

There are a few ways to set the folder to which RESTTopo will download the DEM tif. The folderPath is just a string (text) input, so if you right-click folderPath on the component, you’ll see a menu where you can set a folder path specific to your machine by typing in text. Otherwise, GH has a File Path component which, again, if you right-click you can “Select a directory” and it will help you navigate to an existing folder on your machine. Finally, if you drop a new RESTTopo component on the canvas, it will auto-populate with a temp folder specific to your machine.

-Brian

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Getting there!

I now have an .xml as well as a .tif file in my designated folder.

Nothing showing up in Rhino yet, though - here’s what my GH looks like.

Here are the messages:
image

image

I’m new to Grasshopper, and I’m running into an issue where the GH file in this thread “20231116_3DEP Topo Import.gh” is reporting that the Surface Mapping, and Custom Preview Materials plugin is missing. Where do I go to download these two plugins?
Thank you for any info.
-D

I’m thinking it may be a units issue. For instance, if your boundary curve is 1,000 x 1,000 and units are set to millimeters, you will get errors from the services because your boundary is too small. But if you set Rhino’s units to meters, 1,000m x 1,000m should produce results. After changing units in Rhino, make sure to recompute the definition.

-Brian

Those components are part of the Human add-in available through the package manager.

-Brian

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This is what I get using your EarthAnchorPoint.

-Brian

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Got it!

A few questions…

  1. How do I convert the terrain into an editable mesh?
  2. Is there a way to map the .tif to the mesh?
  3. Regarding the 2 items above, I’ll likely be exporting it to Blender to cut it apart & add detail. Is there a preferred format to keep everything as high quality as possible?

thanks again,
Andrew

I usually bake the texture mapped mesh to Rhino using other Human components. You can create a Rhino material with Create/Modify Materials then set up assignment of the material to the mapped mesh with Create Attributes. Finally bake the mapped mesh with the set attributes using the Bake component. I haven’t used Blender before, but you might try exporting as OBJ.

20231119_3DEP Topo Import & Bake.gh (22.5 KB)

-Brian

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