Startup Movies in Lyra Flicker and trigger ensure: "Only one system can use the SlateThread at the same time. GetMoviePlayer is not compatible with PreLoadScreen."

UE - Media Framework - Dec 20, 2023

When adding startup movies to Lyra, the movie playback flickers and an ensure conditions fails with the message: Ensure condition failed: bSuccess [File:D:\build\++UE5\Sync\Engine\Source\Runtime\M ...

Newly added local variable types are not consistent with prior variable type

UE - Anim - Rigging - Control Rig - Nov 27, 2023

It seems that local variable creation in control rig isn't following the pattern with regular control rig variables (and general blueprint variables) where the last created and/or edited variable ty ...

Crash when spawning actor with no viewport initialized

UE - Editor - Workflow Systems - Nov 22, 2023

If an attempt to spawn an actor is made before the Level Editor Viewport is fully initialized (i.e. before it has had a chance to get rendered at least once), and that actor has no specific Factory ...

Spherecast against complex geometry is returning odd results

UE - Simulation - Physics - Sep 19, 2023

Turning on batching of sphere casts when colliding against complex gives incorrect results. Affects debug output and vehicle wheels and body movement. The issue is with the batch query mode which ...

Edits made to Control Rig Curve Nodes in the Details panel of the blueprint editor are not saved back to original Node

UE - Anim - Rigging - Control Rig - Aug 9, 2023

Reported by licensee in [Link Removed] Changes made to the Curve node in a Control Rig Blueprint aren't saved back to the original node when the changes are made in the Details panel of the bluepri ...

Inaccurate motion vectors when using different position binding in renderer

UE - Niagara - Rendering - Jul 27, 2023

Even though the particles are not moving, and the velocity is zero, the output motion vectors are non-zero. This seems to only happen if using two sources of particle positions.  ...

Iris - check hit in FNetBitStreamWriter::InitBytes if object has only COND_InitialOnly replicated properties

UE - Networking - Iris - Jun 22, 2023

InitOnly FReplicationStateDescriptors will have a value of 0 for ChangeMaskBitCount, so if an object only has COND_InitialOnly properties, its FReplicationProtocol will also have a ChangeMaskBitCoun ...

Objects without custom delta properties can return false for CanSkipUpdate with net.PushModelSkipUndirtiedReplication enabled

UE - Networking - Jun 5, 2023

This seems to occur after receiving a Nak for certain actors. FObjectReplicator::ReceivedNak will decrement SendingRepState.CustomDeltaChangeIndex even if the object has no custom delta properties. ...

Push-model blueprint array property not properly marked dirty if modified by different actor

UE - Framework - Blueprint Compiler - May 17, 2023

In KismetArrayLibrary.h, functions that modify the array property call MARK_PROPERTY_DIRTY(Stack.Object, ArrayProperty). Because these calls use the stack object and not the property's owner, modify ...