Can foliage not emit light onto meshes? (Updated with photos)

Development Rendering
, ,
1

UE 5.1
I have a material that emits light into the scene when the source is a static mesh, but it doesn’t work when that source is foliage.

I’ve searched for answers and only found posts at least 2 years old and none of them offer a solution.

I don’t see anything in the foliage settings that jump out as something I need to turn on to get this effect. Does anyone know how to make it so my foliage emits light onto the scene? I’m very new to the software, so ELI5 would be very much appreciated <3

UPDATE: I’ve narrowed it down (I think). At a certain distance, emissive shading switches to a lower quality on the manually placed static meshes. They still emit some small amount of light, but it’s significantly less bright and accurate. At that point, it looks much more similar to the foliage. Here’s an example with the foliage on the left and manually placed meshes on the right

image
image1425×689 70.3 KB

If I move the camera closer, the lighting suddenly because much brighter and more accurate, but only on the manually placed meshes:

image
image1787×764 90.1 KB

So, now I have two questions. What is causing the switch in the static meshes, and is that low quality setting just forced on the foliage meshes all the time, regardless of distance?

Cheers!

2

In 4.27 you had to jump through hoops to get emissive to work on foliage.
This is likely the same in 5.1

If I remeber correctly you had to enable and use Light Propagation Volumes to get the foliage to actually do what static meshes otherwise just do.

What it comes down to is instancing.
Foliage is instanced.
Runtime local light can only be computed at an acceptable rate when using volumes.
For that, you need distance fields, and a bunch of other settings…

Try to follow a guide for ue4 on LPV. See if that gets 5.1 to work like you need it to.

Other than that, you are probably complaining about eye adaptation doing its job of closing/dilating the camera aperture based on how much light filters in…

1 Like
3

Thanks for that explanation. Most of it is gibberish to me at this point, but I do look forward to what I’ll learn by going off the information you’ve provided. Cheers.