When copying category properties, all the EditConst flags are not checked. This overrides variables that should not be written.

UE - Editor - Workflow Systems - Mar 12, 2024

If you create two actors that have the same structure of variables in a category, and you try to copy the category variables of one actor into the other, variables that have ReadOnly/EditConst speci ...

Playing two instances of the same level sequence with an audio track will not work as expected.

UE - Anim - Sequencer - Mar 11, 2024

Two instances of the same level sequence playing audio will cause the audio to stop playing. ...

CharacterMovementComponent: simulated proxy can go into falling due to linear velocity quantization when using custom gravity

UE - Gameplay - Components - Mar 8, 2024

The character movement component in  void UCharacterMovementComponent::SimulateMovement(float DeltaSeconds) evaluates whether to find the floor when simulating the movement of the simulated proxy ...

Enhanced Input Action Key Remapping maps old mapping over incoming mapping in an unintuitive way

UE - Gameplay - Input - Mar 7, 2024

On EnhancedInputSubsystemInterface.cpp:1040, RebuildControlMappings has a check to preserve mappings for identical action key maps. In most cases, this appears to work correctly; however, in the cas ...

PostLoadGroup can cause materials to cache GWhiteTexture into uniform expressions

UE - Rendering Architecture - Mar 6, 2024

It may occur that during loading screens, materials using material layers will load with GWhiteTexture before the real textures are ready. This seems to be because of a race condition due to PostLoa ...

TakeRecorder does not add a track to a level sequence when niagara FX is spawned

UE - Anim - Sequencer - Mar 5, 2024

In UTakeRecorderActorSource::EnsureObjectTemplateHasComponent() function, MakeUniqueObjectName() generates the same name of a component which CachedObjectTemplate for TakeRecorder has already had. T ...

RenderTrace fatal error, shader expected a uniform buffer at slot 1...

UE - Rendering Architecture - Mar 4, 2024

RenderTrace plugin does not appear to have been updated for a change that moved the GPUScene out of the View buffer to its own uniform buffer. (CL 24027890) The test project is based on FirstPerson ...

Recent change to Material Expression code missing a case for "exp2" function in switch (cpp)

UE - Editor - Content Pipeline - Datasmith - Mar 4, 2024

The function "FMaterialDerivativeAutogen::GetFunc1ReturnType(...)" does not have a case for "EFunc1::Exp2". Also found in Release-5.4, CL: 331987674 ...

GameFrameworkComponentManager crashes when modifying init state callbacks during state change

UE - Gameplay - Feb 28, 2024

The GameFrameworkComponentManager has a system for registering callbacks to execute in response to event changes. This ends up calling UGameFrameworkComponentManager::CallFeatureStateDelegates which ...

Foliage 'BlockAll' instanced static meshes do not affect NavMesh

UE - AI - Navigation - Feb 27, 2024

When placing static mesh foliage and setting the foliage mesh's Collision Preset to Block All,  the placed meshes do not consistently block parts of the nav mesh. Expected: Placed meshes (for examp ...