World Composition Landscape Seams

I am experiencing heightfield seams at the borders of world composition landscapes. The terrain heightfield was generated in worldmachine, and converted to raw files using Photoshop, and saved as .r16.

These were brought into the level using the world composition landscape importer, with a scale of 125 on each dimension. This looks like a straight up precision issue, which could be in the data, or the Editor itself.

Any help would be appreciated!

The .r16 files can be downloaded here:

Hi fisj,

I was able to reproduce this and have entered a bug report, UE-12189 to be entered by the development staff. As a workaround, you can use the smoothing tool with a strength of 0.0 and run that over the seam, which should seal it without smoothing out the landscape details.


It looks like adjacent heightmaps have different values on borders. In the World Machine export dialog there a checkbox “Share Edge Vertices” that must be checked. Like in the picture here.

If they we checked during export, then it’s definitely precision issues.
Also I’m not sure why you need to convert to r16 files in photoshop, World Machine supports exporting into r16.

Exporting directly from WorldMachine Pro as a tiled option works perfectly. Thank you! I wasn’t aware that world machine exported r16 directly, and was also unfamiliar with the tiling functionality.

For future reference, I found this doc after the fact and covers the process well:

For other users who may encounter this issue … a naive export of height using something like photoshop will not work for tiled world composition landscapes - use world machine pro!

I just tried this and this is what I get after rebuilding lighting. I even tried a lightmap res of 4.0 instead of 1.0

I will admit that the seam is not as noticeable after I did the smoothing tool.

Probably my fault as the seams are not perfect… I had to manually export the two tile sets from world machine and apparently that is not perfect unless I upgrade to the professional version for $150…