Creating FTickableObjectBase inherited class in async thread may cause pure virtual function call

UE - Framework - May 22, 2025

Classes that inherit from FTickableObjectBase are added to the tickable queue by the QueueTickableObjectForAdd function during their construction (see FTickableGameObject::FTickableGameObject). At t ...

Reimporting an asset during PIE overwrites the bAllowCPUAccess value to true

UE - Editor - Content Pipeline - Import and Export - May 22, 2025

When reimporting a static mesh asset before PIE execution, the value of bAllowCPUAccess is false.  If reimporting a static mesh asset while PIE is running, the value of bAllowCPUAccess is true. In a ...

Specular highlight and roughness issue on clearcoat material with second normal at certain view angles

UE - Graphics Features - May 21, 2025

Specular highlights on non-Nanite meshes with a clearcoat material that has the second normal enabled will disappear at certain view angles. This can be worked around by adding a constant node to th ...

When importing static mesh using interchange and collision is generated, the asset does not have Collision Generated set to true

UE - Editor - Content Pipeline - Import and Export - May 19, 2025

Context: The Interchange Framework is Unreal Engine's import and export framework. When importing a mesh without collision, collision can be auto-generated. Problem: The problem is when importing s ...

Generated instances can not be cleaned up when PCGVolume is copied to a different level

UE - World Creation - Procedural Tools - May 19, 2025

Copying a PCGVolume beyond a level creates an instance that cannot be deleted. In UE5.5 or later, it is possible to delete the instance by pressing Cleanup button with Ctrl key (purge all components ...

Misaligned sampling in UI Material with with CustomStencil

UE - Graphics Features - May 19, 2025

The output of the CustomStencil node in a User Interface material does not align with the viewport dimensions. Toggling fullscreen/windowed mode (F11) causes the offset to reappear, so scaling the n ...

AnimNotify Issue with LevelSequencer Actor with URO

UE - Anim - Gameplay - May 19, 2025

Sometimes AnimNotify does not fire when an animation is executed under the following conditions. 1. The CharacterMesh's AnimationMode uses UseAnimationAsset 2. CharacterMesh's URO is enabled (Enable ...

Tick functions are skipped on the first frame in package build and standalone PIE

UE - Gameplay - May 19, 2025

It's reported that all Tick functions are skipped on the first frame when running in packaged builds and standalone PIE. This is because both TickVisitedGFrameCounter and GFrameCounter are initializ ...

[AI] SmartObjectSlot does not have a valid node ref even when it should project to navigation.

UE - AI - SmartObject - May 17, 2025

If you request a SmartObject slot entrance location and require it to be navigable, it will return a result that does not include the node ref of the nav poly for the entrance to the slot. Instead i ...

Editing values of a control rig can cause the undo to stop working in Anim Details or Sequencer

UE - Anim - Sequencer - May 16, 2025

It has been observed that the the undo function may stop working after the User changes values of a control rig with the slider in the Sequencer. While using the slider, the value stops chaning afte ...