Directional Light not occluded in Single Layer Water material

I have run into this problem many times before, but I’ve just tried to avoid it. Now I’m doing a project where the issue is affecting the main focus of my film: a small paper boat.

There is an issue with directional lights in UE5, where it is blocked and casts shadows properly with static meshes, landscapes, and other objects, but when a Single Layer Water material is used, as in this project with Fluid Flux, the sun is reflected with no occlusion whatsoever.

This makes for bright highlights and reflections on the dark sides of objects, as well as completely lighting up (unrealistically) the unlit side of my paper boat because there are highlights on the water from the incorrect reflections.

Anyone know of ANY way to make Single Layer Water behave correctly with directional lights?!

Also, any way to make Lumen stop lighting up the dark sides of objects just because there is a reflection on that side? It’s treating the appearance of a reflection as a light source going away from the camera because of screen traces. But if I turn off screen traces, other things look worse. I’m new at this, so maybe there’s a simple solution ya’ll know about already.

Specular occlusion doesn’t appear to work on certain materials when using ray traced shadows. Perhaps there is a CVAR to fix it, but the easiest thing is to simply switch to virtual shadow maps for your sun instead of ray traced shadows.

Raytraced:


VSM: