Unreal Engine Issues
Unreal Engine Issues
Rect lights cause visual noise on the light rendered when using raytracing
UE - Graphics Features - Lumen - Nov 12, 2019Rect lights cause visual noise on the light rendered when using raytracing. It is easier to see when you get rid of all other light sources in the scene. I have attached an example project. This se ...
Niagara Mesh Renderer's ParticleColor is not reflected in raytraced reflections
UE - Graphics Features - Lumen - Jun 2, 2020Mesh's ParticleColor is not reflected in raytraced reflections Sprite Particles do not encounter this issue. ...
Depth of field issues on Translucent Materials with Raytracing and DirectX12 enabled
UE - Graphics Features - Lumen - Oct 9, 2020With DirectX12 and Raytracing enabled, translucent materials are not showing the correct depth of field. Reported in version 4.25.3(CL 13942748). Tested and found in versions 4.25.3 and 4.24.3(C ...
Raytraced lights with Source Length > 0 behave incorrectly with Megalights
UE - Graphics Features - Ray Tracing - Mar 26, 2025When Megalights is enabled, light can leak into areas that should be occluded for lights with smallish (5.0) source length and source size. [Image Removed][Image Removed] This was taken with r.Ray ...
World partition mini map fails to build with an Unhandled Exception while using r.Raytracing.Nanite.Mode=1
UE - Graphics Features - Jan 31, 2023This is a regression. Tested in //UE5/Release-5.0 CL20979098 Build mini map fails with an Unhandled Exception while r.Raytracing.Nanite.Mode=1 is enabled in the DefaultEngine.ini. ...
Raytraced reflections are aliased, but reflections of reflections are not
UE - Graphics Features - Lumen - Mar 3, 2020Raytraced reflections contain aliasing, but the reflections of the aliased reflection do not. In the provided image, you will see plane C shows the reflection of the grid material with aliasing arti ...
Disabling Shadow Denoiser causes raytraced shadows from Rect Lights to disappear
UE - Graphics Features - Lumen - Nov 6, 2020Disabling Shadow Denoiser causes raytraced shadows from Rect Lights to disappear ...
[Groom] Very thin hair has incorrect raytraced shadow on edges
UE - Graphics Features - Lumen - Jun 8, 2020This only happens when 1) Hair Width is very small. e.g. 0.01 in the example 2) Light has raytraced shadow and Samples Per Pixel has a value > 1. e.g. 8 in the example The problem seems to be rel ...
GenerateVisibileRayTracingMeshCommands Severely Reduces Foliage Performance Even if no RayTracing is Used
UE - Graphics Features - Lumen - Sep 18, 2019GenerateVisibileRayTracingMeshCommands Severely Reduces Foliage Performance Even if no RayTracing is Used. Found in 4.23 CL# 8386587 and 4.24 CL# 8748719 ...
[Feature Request] Single Layer Water shader doesn't accept Realtime Raytracing Shadows
UE - Graphics Features - Lumen - Apr 1, 2021This might be feature request? ...