Unreal Engine Issues

Intermittant motion blur issues in content heavy scenes

When using the following RHI/Render thread/GT sync configuration:r.OneFrameThreadLag 1r.GTSyncType 1 The previous skinning bone data can be corrupted and introduce visual artifacts on everything us ...

UGS "Copy to Workspace" copies a preset's categories but not its Custom View

Options -> Presets -> Copy to Workspace copies the selected preset's category choices into the workspace sync filter but drops the preset's Custom View lines. Binding the same preset through the Syn ...

UGS Sync Filter preset dropdown reverts to empty on reopen

In the Sync Filter dialog (Options -> Sync Filter -> Current Workspace), selecting a preset and clicking OK saves the selection correctly and it is applied at sync time, but reopening the dialog sho ...

Virtual Texture Collection doesn't show correct mip level

Textures from VirtualTextureCollections appear blurry because the correct mip level isn’t shown unless FVirtualTextureCollectionResource::InitRHI is modified in VirtualTextureCollection.cpp withProd ...

Values passed through VertexInterpolators are incorrect in the pixel shader on Niagara mesh particles when material uses SubUV animation

Passing through the vertex interpolator, the DebugFloat3Values output appears garbled, but if you remove the VertexInterpolator the particle’s position is accurately returned. This happens with Part ...

Sequencer binding resolve fails in packaged builds for actors in non spatially loaded Level Instances

Skeletal mesh LODs never stream up under SSAM: FSkeletalMeshSceneProxy caches ForceStreamedLOD and is never re-gathered

UE 5.8, cooked build, SSAM enabled (s.StreamableAssets.UseSimpleStreamableAssetManager=1, required by FastGeo). Symptom: characters spawn at a crude LOD and can never stream up for the lifetime of ...

OpenXR: per-frame Color/Depth mismatch caused by unsynchronized swapchain image selection across Game/Render/RHI threads (default xr.OpenXRAcquireMode=2)

Reported via UDN (case No107). Verified against //UE5/Release-5.6 sources; same code present in 5.5, 5.7, 5.8 and Main. Licensee reproduces on 5.3 and 5.6 with the Canon MREAL runtime. Symptom Fra ...

MovieSceneSequencePlayer GetEndTime() reports incorrect end time

We've noticed an inconsistency with UMovieSceneSequencePlayer::GetEndTime(). It does not take into account DurationSubFrames. See UMovieSceneSequencePlayer::GetDuration() for comparison. Also, the c ...

UNetConnection::NotifyConnectionUpdated always sets MyConnectionId to 1

This looks to be due to an oversight in how the conditions are checked in NotifyConnectionUpdated, where the “&&” operator results in MyConnectionId always being set to 0 or 1:if (const uint32 MyCon ...