square rendering artefacts in water and sky

I’m creating a large terrain (64 km^2) in UE5.1 using Brushify and Ultra Dynamic Sky/Weather.

  • Lumen is active
  • static meshes are nanite-enabled, except the landscape (I tried enabling it a number of times but it timed out and crashed the editor)
  • running on a recent build of Windows 10

(1) Editor screencast: artefacts in UE5.1 editor - YouTube
(2) Gameplay preview screencast: artefacts in EU5.1 in-editor gameplay - YouTube

After I added a water surface I noticed a dark square area in the water reflection (in the editor it sometimes seems surrounded by larger square that’s light grey). The clouds are either not reflected inside the square, or are distinctly darker.
In-editor gameplay has a similar square area overhead in the sky where weather phenomena like lightning don’t show.

(1) at 0:42 tiled blocks showing outside of the square that remind me of how meshes without material look, also see (2) 1:19 and elsewhere
(1) 0:47 square area in water shows up very clearly
(2) 1:26 lightning cut off by the square area overhead

I’m wondering where to start looking how to resolve this. I tried changing nearly all UDS parameters I could find, but none seem to get rid of that square.

Any suggestions what I could try?
Thanks!

your latest video showed it to be fixed. sometimes a restart can do wonders :wink:
water is also still in “experimental”. you might have noticed dragging in the standard ocean water in a landscape 4k or above will grind the engine to a halt. will get fixed in 5.2. my guess is when dragging in the plane something happened with a render target and after restarting that reset itself… but not 100% on that :stuck_out_tongue:

Hi - actually, it wasn’t a restart that fixed it.

I don’t know what did it. I changed too many settings I’m afraid, deleted the water asset, re-added it, and the same for UDS.
There are so many possible combinations of UE + add-on settings … :sweat_smile:

But I’m learning fast now, having some time on my hands during the holidays. And I haven’t regretted switching from Unity to UE for a second :ok_hand: