Path tracing gets harsh shading falloff if using area lights

UE - Graphics Features - Lumen - May 24, 2019

Thumbnails do not display shadows after opening and saving the asset

UE - Graphics Features - Lumen - Apr 14, 2020

Shadows in an asset's thumbnail disappear after opening and saving the asset, whether changes are made or not.  Tested: 4.24.3 CL#11590370, 4.25P6 CL#12493028, 4.26 CL#12767035 ...

Crash enabling Stochastic Rect Light with Ray Tracing

UE - Graphics Features - Lumen - Oct 13, 2020

Enabling Stochastic Rect Lights with Ray Tracing causes the project to crash. Reported and tested in version 4.26.0(CL 14419252). Tested and not found in version 4.25.3(CL 13942748).  ...

Motion blur does not work with ray traced translucency enabled

UE - Graphics Features - Lumen - Jun 1, 2021

Refraction of Ray Traced Translucency in Path Trace View is Incorrect

UE - Graphics Features - Lumen - Apr 8, 2019

Refraction of Ray Traced Translucency in Path Trace View is Incorrect. Found in 4.22 CL# 5660361 and 4.23 CL# 5779284 ...

Memory leak when rendering some meshes with ray tracing enabled

UE - Graphics Features - Jul 19, 2021

This memory leak seems to be caused by the TMemStackAllocator of FRayTracingMeshCommandOneFrameArray. Using the FDefaultAllocator for FRayTracingMeshCommandOneFrameArray works as a workaround. // ...

Media Plate Actor becomes blacked out when set to Spawnable in a Level Sequencer

UE - Virtual Production - Rendering - Jun 7, 2023

saving a media plate actor set to spawnable in a level sequence causes the media plate actor to become black. there are two known workarounds 1. toggling the Media plate to Possessable, and Spawnabl ...

New VR-Basic level triggers Metal validation layer assertion

UE - Platform - Apple - Mar 16, 2020

This was discovered externally and reported on UDN here: https://udn.unrealengine.com/questions/563268/mac-editor-crash-when-disable-ambient-occlusion.html ...

Ray Traced Translucency Option Doesn't Function in Post Process Volume

UE - Graphics Features - Lumen - Aug 16, 2019

Ray Traced Translucency Option Doesn't Work in Post Process Volume. Found in 4.23 Preview 6 CL# 7848402, and 4.24 CL# 8074192 Working as expected in 4.22 CL# 7053642 This is a regression. ...

Lumen reflection distortion

UE - Graphics Features - Lumen - May 30, 2024

Lumen reflections appear distorted depending on the camera orientation. ...