I have just started learning Unreal Engine, while following a tutorial by Bad Decisions Studio, here I got an error, that the side wall lights is not properly reflecting, those lights are static mesh with emissive material on it. kindly guide me to solve the problem
Can you try and disable Screen Traces in Lumen Reflections?
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Thank you for assisting me. I adjusted the settings, but the issue remains unresolved. It seems like culling is occurring, though I am unsure of the reason or the cause. I am uncertain whether it is a hardware issue or a problem with the software settings.
I adjusted a minor setting in Path Tracing by enabling the Emissive Materials under the path tracing section. Additionally, in the Lighting components I enabled the Emissive option. Both are described as enhancing the scene’s ability to calculate Emissive materials as a source of light.
You are not Pathrtacing, though. You are in Lit Viewmode, which means you are in the Deferred/Raster path. Are you using Lumen reflections? If you can, could you post a screenshot of those settings in your PPV? It looks like some sort of screen space reflection in your render.
Are they those lights in your Lumen Debug view under Viewmode - Lumen - Overview?
I am unsure of what is happening on my screen; the lights are modeled directly in Unreal and have Emissive material applied to them.
They are not in your Lumen scene, so it’s falling back to screen space reflections. There are many reasons why they are not in there. Are they visible to raytracing? Perhaps it’s the Lumen Scene Detail?
I guess I’m in Lumen scene. if not, can you guide how to active Lumen scene. And raytracing option is not show to me
Lumen scene detail is in the post process volume under Lumen GI.
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Try and increase the scene detail to see if you can get them to change color in the Lumen Scene. Make sure your hardware is a RTX card and can raytrace.
Hello Vikasraj0411,
Reflections in Unreal Engine can be a bit tricky to manage when you’re still learning the software. The engine will always try to optimize reflections for performance reasons, which is why there are so many settings related to them in the project settings.
Following Shaun’s messages and your screenshot, the first thing that stood out to me is your current project settings:
Use Hardware Ray Tracing When Available: Enabled
(This allows full Ray Tracing capabilities if your system supports it, along with other options that can be toggled.)
Software Ray Tracing Mode: Detail
(This uses an optimized version of your mesh for reflections via Mesh Distance Fields, based on voxel technology. If set to Global, it uses a cheaper option called Global Distance Field, also voxel-based but lower resolution.)
Ray Lighting Mode: Hit Lighting for Reflections
(This is a hardware feature that enables high-quality Ray Traced reflections—but it’s performance-intensive.)
What’s strange is that in the Lumen Overview under the Reflections view, you should see “HRT Hit Lighting” written in yellow if hardware tracing is used. But since you’re in Software RT mode, that might be why Shaun asked you to verify if your GPU supports RTX/RT features properly.
If you’re in Software Ray Tracing in Detail mode, like in your screenshot, you’re relying on Distance Fields for reflections. One important thing to understand is that the voxel-based system needs enough mesh data (size and detail) to correctly represent your static meshes in reflections. Try increasing the size or thickness of your mesh to see if that helps.
Another thing to note: if you switch to Hardware RT, translucent materials won’t appear in reflections.
Here are some screenshots to help clarify this.
Hope this helps!
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If you guys don’t mind, kindly guide me where are those settings, that I have to change to get the result, I am using Unreal 5.6 some options are replaced and removed. My hardware spec is Nvidia T400 4GB, 64GB RAM, AMD Ryzen 5 5600 6-core
As far as I know, the NVIDIA T400 and TXX00 series don’t come with hardware ray tracing capabilities. Ray tracing is usually supported in the A-series GPUs, like the A2000 and above.
So if you want to use ray tracing, you’ll need to rely on your CPU and the software-based solutions described in the previous post. (My screenshots were taken from version 5.5 of Unreal Engine.)
In version 5.6, to manage these settings, go to:
Edit → Project Settings → Engine category → Rendering
Then look for the Lumen subcategory and the Hardware Ray Tracing settings.
Or simply type “ray tracing” in the search bar at the top of the Project Settings window.
If you’re sure your GPU doesn’t support Hardware Ray Tracing, you can disable the option:
“Use Hardware Ray Tracing When Available”
At that point, you’ll only be able to use Software Ray Tracing, and you can choose between:
- Global Tracing (uses Global Distance Field)
- Detail Tracing (uses Mesh Distance Field)
Note about UE 5.6:
For some reason, switching between Global and Detail tracing doesn’t seem to update the reflections view properly. I’m not sure if there’s a new setting required to enable Mesh Distance Fields for reflections in this version. If anyone knows more, feel free to chime in!
Currently, to make your small lamp appear in reflections, you have two options:
1.
Enable Screen Space Reflections in your Post Process Volume.
Since this is a screen-based method, the light/lamp must be visible on screen to appear in the reflection.
2.
Increase the size of your lamp’s static mesh so it becomes large enough to be included in the Global Distance Field.
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