Generated definition of BlueprintNativeEvent UFUNCTION in an interface does not include const keyword for return type

UE - Foundation - Core - Aug 15, 2018

UHT does not correctly create generated code for BlueprintNativeEvent UFUNCTIONs in an interface that return const values. In the corresponding .gen.cpp file, the generated code does not include the ...

Material Quality Level not working with Layers

UE - Graphics Features - Jul 6, 2021

Destructing NiagaraParameterStores causes multi threading write conflict

UE - Niagara - Jan 26, 2022

FNiagaraParameterStore::UnbindAll() may be called from both GameThread and RenderingThread. Each may modify the same Binding array, it causes infrequent crashes. In my environment, I was able to r ...

Base Pose Type Not Retained When Retargeting Animation with Additive Anim Type

UE - Anim - Rigging - Retargeting - Apr 22, 2022

Occurs 3/3 Times Base pose animation is not retained when retargeting animation with an additive anim type. ...

Duplicated ChildActor on World Partition Streaming

UE - World Creation - Worldbuilding Tools - World Partition - Feb 5, 2024

The issue is encountered when streaming a world partition an actor with an AChildActorComponent which generates 2 instances instead of one when run as a client in the editor. This behavior does not ...

Dynamic (transient) material instance assignment lost if object spawnable

UE - Anim - Sequencer - Jun 21, 2024

Material Instance Dynamic assigned to Spawnable objects with Editor Utility Widget get reverted when hit the Save button in Sequencer. This appears to come from the Material Instance Dynamic not be ...

A sampling result of DistanceFieldAOHistory is shifted to a wrong position.

UE - Graphics Features - Aug 21, 2024

DistanceFieldAOHistory introduces ghosting at low scalability and low screen percentages. This can lead to AO artifacts and a ghosting effect from the character. This issue was also observed on //U ...

Mesh Paint mode's Texture Paint has obvious artifact with UV seams

UE - Rendering Architecture - Oct 8, 2024

Mesh Painting Texture Paint tool can miss some pixels along UV seams, even with "Enable Seam Painting" set to True. This appears to be because of the difference between rasterization and sampling. ...

The DistanceCurveModifier generates Distance Curves with zero values for Root Motion animations

UE - Anim - Gameplay - Jun 30, 2025

The DistanceCurveModifier data modifier generates curves that return zero values only. This issue has been tested on several Animation Sequences with enabled Root Motion and always occurred. ...

UInstancedStaticMeshComponent::AddInstances does not appear to be adding per-instance previous transforms when enabled

UE - Graphics Features - Dec 3, 2025

Instanced static mesh component does not add instances transforms to PerInstancePrevTransform array when using UInstancedStaticMeshComponent::AddInstances. Additionally Updating the transforms of th ...