Unreal Engine Issues
Unreal Engine Issues
Incorrect rendering result on some geometry and materials in grouped components in SKP imports
TM - Interoperability - Aug 5, 2026Reported in SF [Link Removed] In Twinmotion 2026.1, when importing certain SKP files with grouped components, materials may render incorrectly on some grouped components and will appear with a dark ...
FEvaluateActorReferenceChannels don't run on GameThread
UE - ACT Character - Sequencer - Aug 4, 2026When playing back sequences on a character that is bound users will sometimes run into an ensure from FEvaluateActorReferenceChannels. ...
Color picker widget auto-closes unnecessarily
UE - Editor - Aug 3, 2026A licensee reports that the color picket widget in Unreal Editor closes whenever a blueprint actor (map placed instance of an actor blueprint) receives a property changed event, even if the change e ...
Intermittant motion blur issues in content heavy scenes
UE - Rendering - RHI - Jul 30, 2026When 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 ...
Values passed through VertexInterpolators are incorrect in the pixel shader on Niagara mesh particles when material uses SubUV animation
UE - Rendering - Architecture - Niagara - Jul 29, 2026Passing 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 ...
MovieSceneSequencePlayer GetEndTime() reports incorrect end time
UE - ACT Character - Sequencer - Jul 28, 2026We'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
UE - Networking - Jul 28, 2026This 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 ...
Brick Pattern Artifact in Volumetric Clouds
UE - Rendering - Features - Jul 28, 2026A licensee has reported seeing a repeating brick-like pattern in volumetric clouds when they overlap with very distant geometry (or at the transition between nearby and distant geometry). The artifa ...
Issue with UHLODBuilder::ComputeHLODHash
UE - Engine Scaling - Streaming - Jul 23, 2026The HLOD content hash used to detect changes and trigger rebuilds effectively ignores everything hashed before the source-component loop — including the result of UHLODBuilderSettings::ComputeHLODHa ...