Flickering foliage


I have a strange foliage bug on my landscape. Groups of grass instances are changing brightness, when I move camera. This video shows bug:

Grass near the road become darker or brighter.

Engine scalability settings are all Epic. Other settings and material:

What happens when you disable the “eye adaption”? -> in the post process volume under auto exposure :slight_smile: + place some meshes by hand and then check if your problem still appears

I disabled all posteffects, and it doesn’t solve problem. But I solved problem in another way.:slight_smile:
When I uncheck Cast Dynamic Shadow on the grass instance in foliage window, this visual bug disappears. But the foliage don’t cast shadows! It’s not a big problem with grass, but when trees don’t cast shadows, it looks ugly.
I also got this message:

Large actor? It’s only 300 instances. I’m going to cover all level with the grass and trees and I want them to cast shadows (maybe not grass but trees any way). How can I fix it?

Detailed bug description:

  1. Foliage looks good when I uncheck Cast Dynamic Shadows - but it’s not a solution.
  2. Foliage looks good when I set DistanceField Shadow Distance less then 7k for this level.

You can see it in the video from Editor.

How to fix it?

On your lights, such as directional light, check static instead of stationary/movable, which make it dynamic. If you need the sun to change directions then that might be an issue. A quick fix for the time being I suppose. Then I look at the time stamp of this post, and it’s been 4 years hahaa. I hope you ended up finding your solution.

Try disconnecting the emissive color. The behavior though looks like a LOD kicking in so I would look at the mesh to see how many levels it has. It’s typical to LOD a material to decrease the level of shader complexity so the behavior looks like the emissive kicking in and out.