Windows Metal Shader Compiler creates invalid shaders for iOS

UE - Platform - Apple - Feb 23, 2024

When installed app is started on device, log will say there's missing or invalid metal shaders ...

USkeletalMeshComponent::HandleExistingParallelClothSimulation() calling WaitUntilTaskCompletes can trigger arbitrary task that modifies currently iterated UWorld::ComponentsThatNeedPreEndOfFrameSync

UE - Gameplay - Components - Feb 23, 2024

Context ActorComponents can schedule an end-of-frame update for themselves by calling UWorld::MarkActorComponentForNeededEndOfFrameUpdate. The UWorld will iterate all those actor components once pe ...

Auto Exposure Compensation Curve issue when switching from Manual to Histogram

UE - Rendering Architecture - Feb 21, 2024

When switching the Camera's Exposure Metering Mode from Manual toHistogram, the exposure level resets and takes time to settle. The Licensee has a proposed code change that would fix this issue. Als ...

Auto Exposure Compensation Curve issue when switching from Histogram to Manual

UE - Rendering Architecture - Feb 21, 2024

When switching the Camera's Exposure Metering Mode from Histogram to Manual, there is a single-frame flash. The Licensee has a proposed code change that would fix this issue. Also found in 5.4, CL 3 ...

ResavePackages Commandlet Consistently Crashes in 5.3 In Material PreSave

UE - Rendering Architecture - Materials - Feb 20, 2024

Running the ResavePackages commandlet will consistently result in a crash. The callstack is here: Assertion failed: !IsRooted() [Link Removed] [Line: 265] UnrealEditor_Engine!UMaterialInterface::P ...

Cumulative Patching does not work with Pak signing

UE - Foundation - Feb 20, 2024

Cumulative patching is implemented by copying the generated pak files during staging of the base and each patch to the Releases directory. When creating a patch, all of the pak files from the releas ...

Copied Actors in World Partition Levels Maintain References to Actors They Are Copied From

UE - World Creation - Worldbuilding Tools - World Partition - Feb 19, 2024

When an Actor is duplicated in the editor inside a world partition level it maintains references to the Actor it is a copy of. This can cascade, i.e. Actor C, which is a copy of Actor B which is a c ...

Blueprint "Diff Against Depot": Restoring an instanced object results in reference to the object in the temporary diff asset

UE - Gameplay - Blueprint - Feb 19, 2024

When diffing a blueprint against depot via the Content Browser context menu action "Revision Control > Diff Against Depot", restoring an instanced object property from the depot version results in t ...

MoviePlayer loading screen with FLoadingScreenAttributes::bAllowEngineTick results in high DeltaSeconds tick post-playback

UE - Gameplay - Feb 16, 2024

IGameMoviePlayer playback of a movie during loading screen lets you set bAllowEngineTick  = true as a parameter. This will make FDefaultGameMoviePlayer manually tick the engine: if (GEngine && bAll ...

UNetDriver server-side hitch results in ActorInfo->NextUpdateTime far into future

UE - Networking - Feb 16, 2024

A high UWorld::Tick DeltaSeconds (i.e. GameThread hitch) results in a high UNetDriver::TickFlush DeltaSeconds. This DeltaSeconds can high (many seconds) if the hitch is long. This value then affects ...