Preparing Data – DTM Samples

Here are some sample DTM files for you to play with to learn how to prepare terrain data to create landscapes in UE4.

Most of it comes from the US because there is an abundance of high-quality, free to use/re-distribute data published by the USGS and other sources.

RE-PROJECTING DTM DATA:

Here is the sample data we used in the guide on projecting DTM data.

It’s from the USGS National Map and is a small area north of Las Vegas, Nevada:

• Area is ~36 km sq.
• It’s in a round-Earth projection (Geographic Lat/Lon) and uses the NAD83 datum.
• Pixel units are degrees.
• Resolution is 1/3 arc-seconds/pixel (~10m/pixel).
• Bit depth is 32-bit floating point.
• File format is .dem

[c. 1.0MB]

CHANGING BIT-DEPTH TO FLOAT32:

Here is the sample data we used in the guide on changing the bit-depth to Float32.

Again, it’s from the USGS National Map and is a small area north of Alaska:

• Area is ~1230 km sq.
• It’s in a planar projection (Alaska Albers) and uses the NAD83 datum.
• Pixel units are metres.
• Resolution is 10m.
• Bit depth is 64-bit floating point. We need to change this.
• File format is GeoTIFF

[c. 37.3MB]

MERGING TILES OF DTM DATA:

Here is the sample data we used in the guide on merging multiple tiles of DTM data.

This data is from the UK Environment Agency survey and covers an area near Windermere in the Lake District.

It is made available under the Open Government Licence v3.0.:

• Area is ~4 km sq.
• It’s in a planar projection (British National Grid) and uses the OSGB36 datum.
• Pixel units are metres.
• Resolution is 2m.
• Bit depth is 64-bit floating point.
• File format is ascii (.asc).

[c. 2.4MB]