Unreal Engine Issues
Unreal Engine Issues
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 ...
Custom Primitive Data color widget not applying correctly to static mesh components in Blueprint editor.
UE - Rendering - Architecture - Materials - Jul 23, 2025Context Custom Primitive Data is used to store custom data in an index array that is accessible through Blueprint and code. This allows for variations across instances of the same mesh without needi ...
When exporting a level sequence (with its associated level) to USD, the asset paths for the reference are different from 5.5 and older
UE - Editor - Content Pipeline - USD - Jul 21, 2025In 5.6, a referenced asset path looks something like prepend references = @../../../../../Data/USD/Exports/FN-Main/ExportFolder/Assets/Sphere.usda@ instead of prepend references = ...
Crash when opening a texture or editing its properties after stopping a preview in the material editor
UE - Rendering - Architecture - Materials - Sep 5, 2025When a texture asset has certain properties edited, its PostEditChangeProperty() method calls to UTexture::NotifyMaterials(), which triggers a recompilation of materials that reference it in their m ...
GeometryCollectionPhysicsProxy::FieldParameterUpdateCallback() not removing invalid Commands, leading to performance issues
UE - Runtime - Deformable - Aug 30, 2025GeometryCollectionPhysicsProxy::FieldParameterUpdateCallback() not removing invalid Commands, leading to performance issues. The licensee has provided their analysis: We seem to have stumbled acro ...
Data like Camera Tracks can get corrupted inside Level Sequences when Undoing some operations
UE - Anim - Sequencer - Jul 22, 2025Camera trucks can get in a invalid state when you undo certain operations. One example would be undoing a camera set that has been added to a camera track. When you undo that operation, other camera ...
Geometry Collection's Chaos Cache Static Pose Scrubbing broken in 5.6 due to Custom Renderer GeometryCollectionRootProxyRenderer
UE - Runtime - Deformable - Aug 26, 2025Geometry Collection's Chaos Cache Static Pose Scrubbing broken in 5.6 due to Custom Renderer GeometryCollectionRootProxyRenderer. The licensee has provided his analysis: In 5.6, when creating a Geo ...
ULevelInstanceSubsystem::CreateLevelInstanceFrom() is not honoring parameters bAlwaysShowDialog and LevelPackageName
UE - World Creation - Worldbuilding Tools - Level Instances - Aug 6, 2025A Level Instance or Packed Level Actor can be created through editor scripting by using function ULevelInstanceSubsystem::CreateLevelInstanceFrom(), which receives parameters packed in the FNewLevel ...
Crash when clicking "Reset to Default" button on the Details Panel for the MaterialAttributeLayers material node.
UE - Rendering - Architecture - Materials - Jul 15, 2025This crash repros from at least UE 5.3 and up to latest. The following assert is hit: Assertion failed: (Index >= 0) & (Index < ArrayNum) [Link Removed] [Line: 1067] Array index out of bounds: 0 in ...
Destroying a welded actor is causing an Array index out of bounds crash on 5.6
UE - Runtime - Simulation - Jul 30, 2025Destroying a welded actor is causing an Array index out of bounds crash on 5.6. The licensee has provided a repro project that reliably causes a crash whenever the spawned actor is destroyed. There ...