Light function does not work with volumetric fog when not compatible with light atlas

UE - Graphics Features - Mar 28, 2025

Light functions do not work as intended with volumetric fog when using clamped mask textures which are not compatible with the light function atlas. In light functions materials, when using any UV ...

Cannot change the Strength value on a Physics Constraint in the Viewport Details panel

UE - Simulation - Physics - Jan 5, 2017

Cannot change the Strength value on a Physics Constraint to anything other than the default value in the Viewport Details panel. When changed the editor will pause and replace the value with — This ...

Assert when having too many VR devices

UE - Platform - XR - Aug 31, 2018

Internal team is encountering a crash when adding too many VR devices. Email thread titled "Re: Crash Logs" The bug is an internal limit of devices the code supports, which is 8. If a controller o ...

Physics replicates incorrectly on the Client-Side on sloped surfaces

UE - Simulation - Physics - Jul 30, 2019

Replicated objects don't behave correctly on the client-side on slopes when not sleeping. By placing two cubes on one another and slightly rotating the bottom one to create a very gentle slope, the ...

Editor crashes when attempting to press tab while editing transform values in structs

Tools - Dec 23, 2014

Editor crashes if a user presses tab while editing transform values in a blueprint struct. Note: This only occurs while editing transform variables, no other var causes this crash. Logs and Dump f ...

Uniform scaling in the viewport not working as expected when additive mode is enabled

UE - Editor - Workflow Systems - Apr 2, 2022

The uniform scaling does not work as expected Repro Steps: 1) Add a cube to a level 2) Set the scale (X = 16, Y=9, Z=9) 3) Click the Lock icon to activate the Uniform Scale feature 4) In the viewpor ...

Large World Coordinates appears to not work for Niagara Mesh Particles

UE - Graphics Features - Nov 28, 2024

When a Niagara System is placed at around 10^8 units away from the origin, the movements of the mesh particles aren't smooth as expected, but jumpy. These particles behave as if they are using a flo ...

Decals custom depth/stencil side effect from Lumen

UE - Graphics Features - Oct 15, 2024

The order of passes related to Decal rendering (without the DBuffer) and CustomDepth is changed by the CVar "r.Lumen.AsyncCompute", even when Lumen is not enabled. This causes Decal Materials that ...

Crash when using StaticDuplicateObject with mismathced Source and Destination class types

UE - Foundation - Jun 19, 2025

Starting in Unreal Engine 5.4, StaticDuplicateObject internally switched to using Unversioned Property Serialization (UPS) for performance reasons. However, UPS assumes the source and destination ob ...

[CrashReport] UE4Editor_Engine!UAnimMontage::IsValidAdditive() [animmontage.cpp:702]

OLD - Anim - May 19, 2016

Error message: Stack overflow - code c00000fd (first/second chance not available) Source Context: 687 if (SyncGroup != NAME_None) 688 { 689 CollectMarkers(); 690 ...