Unreal Engine Issues

Copied Actors in World Partition Levels Maintain References to Actors They Are Copied From

When an Actor is duplicated in the editor inside a world partition level it maintains references to the Actor it is a copy of. This can cascade, i.e. Actor C, which is a copy of Actor B which is a c ...

UDN - Crash reverting SkeletalMesh unsaved changes

Blueprint "Diff Against Depot": Restoring an instanced object results in reference to the object in the temporary diff asset

When diffing a blueprint against depot via the Content Browser context menu action "Revision Control > Diff Against Depot", restoring an instanced object property from the depot version results in t ...

Replace Transform Track setting not used when importing FBX through scripting.

Importing the fbx uses the default settings, which aren't accessed through scripting, so they cannot be changed. To circumvent this  MovieSceneToolHelpers::ImportFBXIfReady caches the defaults, and ...

MoviePlayer loading screen with FLoadingScreenAttributes::bAllowEngineTick results in high DeltaSeconds tick post-playback

IGameMoviePlayer playback of a movie during loading screen lets you set bAllowEngineTick  = true as a parameter. This will make FDefaultGameMoviePlayer manually tick the engine: if (GEngine && bAll ...

UNetDriver server-side hitch results in ActorInfo->NextUpdateTime far into future

A high UWorld::Tick DeltaSeconds (i.e. GameThread hitch) results in a high UNetDriver::TickFlush DeltaSeconds. This DeltaSeconds can high (many seconds) if the hitch is long. This value then affects ...

In Editor, Blueprint resources are not freed up when the Blueprint is closed

It appears that the preview scene used to render thumbnails is not destroyed after a thumbnail is rendered, even after the blueprint editor is closed and GC is run. Also found in Release-5.4, CL: 31 ...

USplineComponent::GetSplinePointAt() returns FSplinePoint with incorrect Type

USplineComponent::GetSplinePointAt() returns an FSplinePoint with the ESplinePointType 'CurveCustomTangent' rather than the type from the setup.Expected: It should return the correct type. ...

Cursor input does not work properly in exclusive fullscreen mode on a secondary monitor

Input doesn't seem to work properly when using exclusive fullscreen mode on some monitor other than the primary monitor. This is similar to other issues we've seen in the past with the cursor being ...

Niagara user parameters out of sync between the Sequencer and the Details panel

User Parameters on Niagara actors do not sync in the details panel when animated with Sequencer. Scrubbing in sequencer does not update the details panel. ...