Crash during cloth initializations while the debug materials are being loaded.

UE - Simulation - Physics - Character - Feb 15, 2023

The FGCObject::AddReferencedObjects() can be called during the LoadObject for the cloth debug materials, while the material object pointers are not yet initiliazed, causing the editor to crash. ...

When editing a Niagara module an error can occur if using non-module functions, even with a correctly set usage bitmask

UE - Niagara - Feb 14, 2023

When editing the module the call to FHlslNiagaraTranslator::HandleDataInterfaceCall has the usage "Module", so it treads the module as if that was its stack context, even though the module's usage b ...

Stateless Connect Handler's SessionId and ClientId checks not working with SteamSockets

UE - Online - Feb 14, 2023

We've had a couple of reports of the recently added session/client id checks in the StatelessConnectHandlerComponent failing when using SteamSockets. The connections fail with the "Rejecting handsha ...

GameThread + AsyncLoadingThread deadlock - StaticLoadObject vs. StaticAllocateObject

UE - Foundation - Core - UObject - Feb 14, 2023

User reported encountering a deadlock between GameThread and AsyncLoadingThread and provided two callstacks.User quote I've been running into a deadlock intermittently with a custom blueprint conso ...

AnimDrawDebug does not work if using RootMotion from Everything

UE - Anim - Gameplay - Feb 14, 2023

Debug drawing with AnimDarwDebug~ does not work when RootMotionMode is set to "RootMotion from Everything". In addition, the same issue occurs when MultiThread of Animation is turned off. Licensee ...

FMassArchetypeData::ExecutionFunctionForChunk crashes on binding shared fragments

UE - AI - Mass - Feb 14, 2023

FMassArchetypeData::ExecutionFunctionForChunk is using wrong mappings while binding shared fragments. It's using RequirementMapping.ChunkFragments while it should use RequirementMapping.ConstSharedF ...

crash from a race condition between interchange worker dispatcher and worker handler

UE - Editor - Content Pipeline - Import and Export - Feb 13, 2023

Atmosphere related scan line artifacts for Path Tracer with MGPU

UE - Graphics Features - Path Tracer - Feb 10, 2023

There are two UDNs related to this issue.  It makes the Path Tracer unusable with MGPU, with atmosphere enabled. I already have a one-line fix implemented and tested.  The atmosphere scan line arti ...

Alpha blending is done twice when using RenderOpacity of RetainerBox's parent slot

UE - Editor - UI Systems - UMG - Feb 10, 2023

Licensee reported that alpha blending is done twice in the code below, and the fix below seems to fix it. .\Engine\Source\Runtime\UMG\Private\Slate\SRetainerWidget.cpp From:const FLinearColor Compu ...

Stencil Test Post Process Breaks in Stereo Rendering

UE - Platform - XR - Feb 9, 2023

[Link Removed] post process material is blacking out our left eye A test project is provided. ...