Unreal Engine Issues
Unreal Engine Issues
Save process fails for BuiltData.uassets when trying to PIE - Standalone Game
Tools - Jul 10, 2017The following can be observed in the output log for the various BuiltData.uassets:Cmd: OBJ SAVEPACKAGE PACKAGE="/Game/Maps/Highrise_Audio_BuiltData" FILE="../../../../../Builds/Release-4.17/Samples/ ...
Attaching New Camera Actor to Spring Arm Component does not set the Location Correctly
UE - Gameplay - Blueprint - Apr 2, 2015After adding a new Camera Actor Component within Blueprints to an existing Spring Arm Component, the Camera Component adopts the location settings , but does not set its location within the viewport ...
Unexpected behavior occurs when the default elements of a TMap in an Actor Component are modified in an instance of a Blueprint containing that Actor Component
UE - Gameplay - Blueprint - Jan 17, 2017Adding an Actor Component that contains a TMap property to a Blueprint results in unexpected behavior when default elements of the TMap are modified in an instance of the Blueprint in the level:Addi ...
World Memory Leaks crash with a hidden sublevel to a redirector
Tools - Dec 8, 2020From UDN: The reason it crashes is because Child doesn't get garbage collected, which is because it still has the RF_Standalone flag. UEditorEngine::EditorDestroyWorld clears RF_Standalone flag ...
NPC - Does not get updates from Material Parameter Collection changes in the editor
UE - Niagara - Sep 30, 2024When an MPC is selected as the Source Material Collection for an NPC, all of its current parameters are carried over to the NPC with their current values. After that, if parameters are added to, rem ...
BP compiler crash
UE - Gameplay - Blueprint Compiler - Nov 24, 2020The crash can be reproduced on the 4.26P7 or the Release4.26 stream. Following the repro steps will result in hitting the following assert: Assertion failed: !HasAnyFlags(RF_NeedLoad|RF_NeedPostLo ...
Physics simulation shows strange behavior with specific skeletal mesh configurations
UE - Simulation - Physics - Mar 3, 2017PhAT is inconsistent on when it does and doesn't apply scale to Constraint positions. This leads to cases where the positions provided create constraints that may not work when the Preview Skeletal ...
Exception on missing file during GC in horde storage
UE - Foundation - Horde - Storage - May 7, 2025During GC, if a file was manually deleted (but the storage system is still track), GC can erroneously fail (and never remove the reference). This causes a backup in GC, putting the whole algorithm i ...
Conflict between sequencer transform track and Parent Constraint from the Animation Mode breaks temporary pivot translation on any actor
UE - Anim - Anim in Engine - Jul 15, 2025Note: This affects all versions from at least UE 5.3, including mainline latest. The "Animation" Editor Mode allows creating constraints for level actors. One of these, the "Parent" constraint, con ...
Project does not cook with actors containing ModularSynth component
UE - Audio - Sep 11, 2017A project does not cook with actors containing ModularSynth component. The error is a follows UATHelper: Packaging (Windows (64-bit)): Cook: LogWindows: Error: begin: stack for UAT UATHelper: Pack ...