Wolrd Partition Foliage Builder - Fails to build with multiple external actor folders.

UE - World Creation - Worldbuilding Tools - World Partition - Apr 1, 2025

Hello, We are building a world with world partition & a lot of nanite foliage. We want to modify out Foliage Instance grid size via the commandlet. [Link Removed] Even in a new empty level the c ...

Skylighting on distant objects causes severe flickering with Lumen

UE - Graphics Features - Lumen - Mar 31, 2025

Lighting on distant meshes flickers when using Lumen and Skylights. Turning Lumen off and lighting from the skylight is stable. Turning off Lumen screen traces also lowers the amount of flickering ...

UAnimNotify::Notify not called during USkeletalMeshComponent interaction with UPhysicsControlComponent when PhysicsBlendWeight is zero

UE - Anim - Synthesis - Physics Control - Mar 30, 2025

UAnimNotify::Notify not called during USkeletalMeshComponent interaction with UPhysicsControlComponent when PhysicsBlendWeight is zero. The licensee has provided his analysis of the code: If USkelet ...

Distance Field AO from Moveable Skylight (non-Lumen) invalidates AO incorrectly with a screenspace offset to the right of moving objects

UE - Graphics Features - Mar 25, 2025

When Global Illumination is set to “None” in the project settings the ambient occlusion does not correctly render shadows for moving objects. This has been observed in versions 5.4 and above. ...

Datasmith Export Bug with Camera Target

UE - Editor - Content Pipeline - Datasmith - Exporters - Mar 7, 2025

Potential bug was encountered when exporting vray cameras and their targets that have been path-constraint to corresponding splines. The resulting export file shows no camera targets; hence, missing ...

Regression: Several project settings, especially from built-in Plugins, are being silently erased when previously they were not, which is perceived as a bug

UE - Foundation - Feb 28, 2025

In UE's Project Settings, some pages are saved automatically to the project's "Config/Default<CATEGORY>.ini" file (meant to be version-controlled) on every change. Other pages have buttons "Set as D ...

Linear interpolation occurs on constant tangent curve partially

UE - Anim - Runtime - Feb 17, 2025

When using UV scrolling for a flipbook-like animation in Animation Sequence, creating keys with "Constant Tangent" settings on Curve Editor does not result in an instantaneous change to the specifie ...

Duplicating many Actors at once in a Level Instance while in Level Instance Edit will result in a jumbled mess of Actors on the Persistent Level

UE - World Creation - Worldbuilding Tools - Level Instances - Feb 12, 2025

Duplicating many Actors at once in a Level Instance while in Level Instance Edit will result in a jumbled mess of Actors on the Persistent Level. The licensee has encountered this in Unreal 5.4 and ...

Mirror operation on Physics Asset produces wrong results for constraints, including flipped axes

UE - Simulation - Core - Feb 7, 2025

The Physics Asset Editor has a "mirror" feature that allows physics bodies and constraints to be mirrored from one side of a skeleton to the other. If this operation worked correctly, it could save ...

An ensure is triggered when a StaticMesh is set inside a StaticMeshComponent on an actor, and another actor references the static mesh actor from two child actor components.

UE - Framework - Blueprint - Feb 5, 2025

There is an issue when setting a Static Mesh inside a blueprint that it is referenced by another blueprint with more than one child actor. An ensure is triggered inside the engine, and there is a ...