Download

World machine - scaling heightmap

Hi,

I am trying to get a 5041x5041 DEM file from World Machine to unreal with the correct scale. (50,41 km)

I am a bit confused on how I should get the numbers right, for the terrain to become 50,41 km in Unreal.

Do I need to scale the 4097x4097 back to to 5041 in Unreal?

Any help is greatly appreciated. I have been reading all the stuff in the Wiki page, but I simply can’t relate the examples to my own case

World Machine settings.JPG

Hi!

I’m kind of fumbling with something similar, but the first thing you need to decide is your density of vertices or height points.
DEM files have a certain resolution; One height value per, usually 10 or 25 meters for the free data. Sometimes 1m or lower.
Unreal terrains at 100% size (default) will assume each height point is 100 Unreal units (cm) apart, so your 4097 map would be roughly 4km in 100% size. To get it 50km you’d have to size it up over ten times, but it would still only have the 4097 pixels so the terrain will be very rough.

If you want 50 x 50 km of 1m resolution data you will have to tile your map as the max height map size is around 8000.

Hi!

Thanks for the answer!

The DEM I have has 10 meter resolution, so the terrain will certainly be quite rough. But I am using it to illustrate a large national park, so it is not crucial for the terrain to be perfect down to every meter. What is more important is that scaling is correct in relation to width/height. Naturally I would also like to keep the 10 meter resolution in unreal to get as much detail as possible, and this is where I get confused.

Since my heightmap is exactly 5041 x 5041 pixels, I guess thats the maximum resolution I have available. The heightspan in the files goes from 0 to 1900 meters.

Until now I thought UE only accepted heightmaps in the exact sizes given in the TchnicalGuide (8129*8129, 4033x4033, 2017x2017 etc), but the 5041x5041 map was accepted. But with autofit my terrain’s overall resolution is now 5101x5101 :confused:

heightmap..JPG

Another issue is naturally what scale I should be using to achieve the 1900 meter height?