Terrain generated from heightmaps

This tool uses the displace modifier on a grid mesh to produce a terrain using the elevation data from a heightmap.

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Heightmap File

This input sets the map to use. These can be either heightmaps, STRM, or Gridded ASCII files.

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A heightmap (also know as heightfield) is a greyscale image representing elevation data. You can find them online by googling, or from websites like Natural Earth

Note

If you want to know more about heightmaps check this Wikipedia article.

STRM stands for Shuttle Radar Topography Mission. These files usually have a .HGT extension and contain elevation data obtained during the SRTM by NASA and the National Geospatial-Intelligence Agency (NGA).

Gridded ASCII files usually have an extension of .ASC and are plain-text based. That means you can open them in a text editor to inspect or edit. Gridded ASCII is a intermediate exchange format and not something intended for primary input/output. You might find them as an export option in GIS software.

Both STRM and Gridded ASCII files are converted to heightmaps internally. You can find the image files in the UV/Image editor and save them as separate files in case you want to have heightmaps of these files.

To select a file click the Select a Heightmap button and navigate to the file. Note that once you select a heightmap you will see a preview of it, and the button’s text will change to the name of the image file. You can click the preview to see a list of heightmaps you have previously loaded.

Common issues

Some heightmaps can produce strange artifacts around the edges (see image), this is a UV issue and can you can fix easily.

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Simply enter edit mode and go into the UV/Image editor, select everything (with the a key) and scale it down just a bit.

General Settings

Strength

How strong the displacement is (vertical scale of features)

Size

Sets the size in real world units

Detail level

Set vertex count for the base grid (in segments). Note that the grid has to be UV Unwrapped to apply the displacement and this can be slow with high vertex counts.

Note

Since this terrain object uses a displacement modifier, you can tweak it after generating it. Check the modifiers tab in the properties editor. Don’t forget to update the vertex groups using the Tools panel. You can also change the texture image, by going into the texture tab.

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