Swarm: Not able to set number of processors to use for Swarm from the UI

UE - Graphics Features - Aug 25, 2015

There is a setting called "LocalJobsDefaultProcessorCount" in the Developer Settings tab in Swarm. After the change to make Lightmass build asynchronously while the user keeps working, this set ...

Frequent ensure opening meshes on Mac, locks up AMD machines

UE - Graphics Features - Jun 6, 2017

REGRESSION No, I was able to reproduce the hard lock in 4.16.1. A frequent ensure occurs when opening static or skeletal meshes on Mac. Doesn't reproduce 100% of the time, but I've gotten it about ...

Navmesh seems to have buggy behavior when interacting with HISMCs that programmatically set mesh via SetStaticMesh.

UE - AI - Mar 6, 2020

Both versions works correctly if HISMC is pre-placed (generated in ConstructionScript). Only when generated dynamically does it fails. The Navmesh isn't being updated after SetStaticMesh and AddInst ...

C# UHT fails to recognize delegates declared in another class's namespace

UE - Foundation - Cpp Tools - UnrealHeaderTool - Dec 14, 2022

Repro Rate: 3/3 This issue occurs in the live build //UE5/Release-5.1 at CL 23058290. This issue has also been regression tested against //UE5/Release-5.0 at CL 20979098 and is confirmed to be a r ...

WindDirectionalSourceComponent.h has a meta edit condition that, by referencing an undefined property (bSimulatePhysics), throws an error

UE - Framework - Apr 15, 2025

WindDirectionalSourceComponent.h has a meta edit condition that, by referencing an undefined class property (bSimulatePhysics), throws an error in the logs: LogEditCondition: Error: EditCondition pa ...

Cloth Simulation Doesn't Work When Clothing Data Is Applied Before Being Painted

UE - Simulation - Physics - Character - Jan 17, 2020

When clothing data is applied before painting the influence on the section the cloth doesn't simulate. I tested this using the Paragion: Twinblast actionhero skeletal mesh asset. Found in 4.24.1 C ...

Calling "GetCameraImage" rapidly ~10 times causes ARKit camera feed to stop updating

UE - Platform - XR - Nov 8, 2018

If you call the "GetCameraImage" function rapidly ~10 times, it causes the ARKit camera feed to stop updating.  Waiting for awhile or tapping some more seems to bring it back.   Tested on macOS H ...

Using Fixed Frame Rate Increases the Speed of Auto Save

UE - Foundation - Core - Oct 26, 2015

Using a lower fixed frame rate (i.e. 20fps) causes the auto save timer (when set to the default of 10) to count down in 3 seconds. Found in 4.10 Preview 2 CL 2733139. Reproduced in 4.9.2 binary an ...

Variable Names with a Leading Space Cannot be Copied

UE - Gameplay - Blueprint - Nov 9, 2015

If you begin a variable name with a space, attempting to copy any instances of that blueprint will prompt an error warning: "Unknown property in <BlueprintName>: <VarName> = <Value>. Found in 4.9.2 ...

Importing multiple SpeedTree assets that use the same texture will not assign correctly

UE - Graphics Features - Sep 25, 2015

When importing multiple SpeedTree assets that use the same material will cause one to import blank (black) materials and assigned. This happens when importing into the same folder, however, if impor ...