Users can't change flags on asset entries in PSD when the asset was added via a Branch In notify

UE - Anim - Gameplay - Mar 19, 2025

Assets added to a PSD via a Branch In notify can't have their flags changed within the database. When the flags (like mirror, disable, etc) are changed, they revert back to the original value when ...

Chaos Vehicle does not make them CCD

UE - Simulation - Physics - Jan 10, 2024

AWheeledVehiclePawn class tries to use CCD in the constructor, but Mesh->BodyInstance.bUseCCD = true this code does not work to activate CCD because Physics Assets could not be available at this ...

UBT Output log encoding does not match if non-ASCII characters are in the UBT output

UE - Foundation - Cpp Tools - UnrealBuildTool - Nov 21, 2019

UBT Output log encoding does not match if non-ASCII characters are in the UBT output. Before UE4.23, UBT output encoding problems only exist in the editor "Compiler Log" under Developer Tools, and i ...

Crash when a Deferred Decal (Translucent) base material has a Nanite Override (Masked Surface) Material and the mesh has Nanite + Ray Tracing enabled.

UE - Graphics Features - Ray Tracing - Aug 14, 2025

A crash occurs when Nanite override material instance is used in a project with Ray tracing enabled where: 1 The Material assigned to the static mesh uses Deferred Decal / Translucent and the Nani ...

Instanced static meshes fire an erroneous performance assert about loose parameters.

UE - Graphics Features - Sep 4, 2019

 "This ensure is intended to catch regressions where rendering programmers add a loose parameter to LocalVertexFactory, breaking dynamic instancing on regular static meshes.  InstancedStaticMeshes c ...

GenerateProxyMesh causes incorrect transform in ISM using Scale

UE - World Creation - Worldbuilding Tools - HLOD - Aug 20, 2019

MeshVertex has been converted by component transform before being converted by instance transform. It is ( Vertex * ComponentTransform ) * InstanceTransform. I thought it has to be converted by (Ve ...

FCDODiffControl doesn't properly account for lists of differing size.

UE - Gameplay - Blueprint - Sep 21, 2016

FCDODiffControl doesn't properly account for lists of differing size. The issues are marked in the following code:int IterOld = 0; int IterNew = 0; while (IterOld != OldProperties.Num() || IterNew ...

TickComponent and PostPhysicsTick in SkeletalMeshComponent can cause simultaneous read/write access

UE - Anim - Runtime - Jan 18, 2023

When a SkeletalMeshComponent is restarted by calling in order of   SetSimulatePhysics and SetComponentTickEnabled, the TickComponent and EndPhysicsTick are executed simultaneously. As a result, the ...

Sequencer autosorts alphabetically on undo

UE - Anim - Sequencer - Sep 8, 2023

[Link Removed] Jan Kaluza 2023-09-08 15:37:18 UTC I just ran into a very frustrating bug: I have around 60 actors in a sequence, and I reordered them to be in the order that I wanted to animate them ...

Packaging for HTML5 seems to have grown in package size

UE - Platform - Mobile - Aug 30, 2016

The size of packages for HTML5 has greatly increased since 4.10.4 to 4.11.2 and has since increased. Example: First person template, no starter content - size of whole HTML5 folder once packaged: 7 ...