UGameUserSettings::ValidateSettings fails to wipe GameUserSettings.ini

UE - Framework - Mar 4, 2025

When changing the version in UGameUserSettings, the expected behaviour is that GameUserSettings.ini will be wiped/delete and then regenerated. The actual behaviour is that within the ValidateSetting ...

FBX import freezes in DataPrep

UE - Editor - Content Pipeline - Visual Dataprep - Mar 3, 2025

FBX file import freezes UE while trying to import into DataPrep by the Interchange importer. The import will start, but then a message will pop up stating "Creating snapshot of world content ... " ...

When using 'r.VT.SplitPhysicalPoolSize 64' with nanite meshes, mesh painting does not update in real time (only updates after stroke finished), duplicates mesh painting across separate instances of a mesh, and sometimes doesn't show up in PIE.

UE - Rendering Architecture - Mar 3, 2025

When using Mesh Painting on nanite meshes in 5.5 with 'r.VT.SplitPhysicalPoolSize' set to non-zero values (e.g. 16, 64), several issues occur, such as: 1. Painting doesn't update in real time (only ...

NiagaraSystem with EniagaraGpuComputeTickStage::PostInitViews rarely crashes due to multi-thread race conflicts

UE - Niagara - Mar 1, 2025

NiagaraSystem with EEiagaraGpuComputeTickStage::PostInitViews should not have bSupportsParallelGDME because of possible multi-threaded contention, but FNiagaraSystemInstanceController::GetGpuCompute ...

Niagara - When Interpolated Spawning is disabled, the first frame of each particle unexpectedly does not take into account the Particle Update stage

UE - Niagara - Feb 28, 2025

Foreword: Even if the behavior described here is by design, it is rarely (if ever) expected or desired. This was discussed and agreed to be treated as a bug. Explanation below. When interpolated sp ...

Shader Symbols not Generated for Windows Platform when r.Shaders.Symbols=1

UE - Rendering Architecture - Shaders - Feb 28, 2025

Shader symbols are not generated for the Windows platform. Attempts were made to set the r.Shaders.Symbols=1 value in the projects DefaultEngine.ini, the engines ConsoleVariables.ini and the engine ...

Virtual Texture Data GetNumMips reports one fewer mip than expected

UE - Graphics Features - Feb 27, 2025

FVirtualTextureBuiltData::GetNumMips() can return 1 fewer mip than it should due to a potential clamping issue at the end of FVirtualTextureBuilderDerivedInfo::InitializeFromBuildSettings() where it ...

OnComponentWake Event does not trigger when the physical body is awoken by a Force

UE - Simulation - Physics - Feb 27, 2025

OnComponentWake Event does not trigger when the physical body is awoken by a Force. The steps described on Steps To Reproduce is enough to replicate this behavior. The OnComponentWake event is only ...

In Packaged builds, Chaos Cache Manager can't animate Geometry Collections with Nanite Enabled if Cache Mode is set to Static Pose

UE - Simulation - Physics - Destruction - Feb 27, 2025

In Packaged builds, Chaos Cache Manager (CCM) can't animate Geometry Collections (GC) with Nanite Enabled if Cache Mode is set to Static Pose. The licensee tried to animate a CCM using Sequencer onl ...