What I’m experiencing was there since I started to work with WM2 + UE4, but generally after the terrain is textured and a proper lighting is done in game engine this problem is really hard to see but I want to get rid of it once and for all.
It definitely looks like a precision-terracing issue. I’m not the best person to answer questions on the UE4 side of things. Usually 16bit precision is more than enough.
To double check, load your exported file back into WM with a file input and make sure you’re not seeing any terracing inside WM in the re-imported heightfield. If you do not, then the problem is purely on the UE4 import side of things, which hopefully someone else can chime in here!
I am a UDK user and I use Landscape system. I guess it almost the same in UE4.
I export in 4033 from WM and import it directly into UDK (no resizing inside photoshop), Maybe it happens something when you resize it and saves it in photoshop?
TBH, if your heightmap is 4033x4033 in engine you should also create a landscape of 4033x4033 meters. Creating bigger than that means you are stretching your heightmap which results in loss of quality.
Well if you want a 10x10km map why not just build a 10x10km heightmap in wm instead of stretching a smaller one? you’d get a lot more details that way.
I believe problem is that you are resizing in photoshop. What kind of .raw did you save in photoshop? Adobe’s raw implementations are meant for photography, not high precision heightmaps.
Try resizing in wm itself. Import using file input, then export with height output with your new extents.
The artifacts are also present if I’m directly importing from world machine. I figured the root of the problem is within UE4. Those artifacts appear only on 8km landscapes. If I use the same hieghtmap to create a 4km or anything lower there are no problems like that.