FFastArraySerializer::DeltaFlags may be saved to blueprint CDO, causing delta struct serialization to be skipped

UE - Networking - Mar 28, 2025

When an actor's replicator is first created and initialized, FObjectReplicator::InitWithObject will use the archetype as the source object for copying the properties. From there, the custom delta pr ...

Material Layers Relink Button Missing

UE - Rendering - Architecture - Materials - Mar 26, 2025

The Relink button is missing (as are the Save Sibling and Save Child buttons) on Material Instances that use Material Attributes Layers in 5.5. ...

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

UE - Rendering - 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. ...

Follower mesh components don't inherit the lead component's recently rendered flag

UE - Anim - Runtime - Mar 25, 2025

Follower mesh components have their recently rendered flag set in their TickComponent method. This means that if a user turns tick off on a follower component, the recently rendered flag isn't upda ...

In Vehicle sims, CenterOfMass override isn't factored into UpdateMassProperties

UE - Simulation - Gameplay - Mar 24, 2025

Origin from this UDN ticket, https://udn.unrealengine.com/s/question/0D5QP00000sGtbO0AS/chaosvehiclemovementcomponent-intertia-tensor-isnt-adjusted-for-center-of-mass-override?fromCase=1 TLDR is th ...

Scenecapturecomponent not including Niagara effect if custom renderpass is used

UE - Rendering - Graphics Features - Mar 20, 2025

When using an "FSceneRenderer::CustomRenderPasses", the View never has Distance Field textures assigned. Can it instead reuse the Distance Field clipmap from the main view? ...

FSkeletalMeshComponentInstanceData subclasses FSceneComponentInstanceData instead of FPrimitiveComponentInstanceData

UE - Anim - Rigging - Mar 19, 2025

FSkeletalMeshComponentInstanceData subclasses FSceneComponentInstanceData instead of FPrimitiveComponentInstanceData. When calling ApplyToComponent() the SceneComponentInstanceData version will be c ...

HDR (eye adaptation) visualization has incorrect output when Allow static lighting is disabled

UE - Rendering - Graphics Features - Mar 19, 2025

Licensees have reported that this issue occurs in UE 5.5 and does not appear to occur in UE 5.4 or with Substrate enabled. ...

Discrepancy in FBX import on animations

UE - Editor - Content Pipeline - FBX - Mar 19, 2025

In the attached screenshots, the following Animation Sequence assets are wrong: * FX_WST050_pSphereB1_TS_AnimFX_WST050_pSphereC1_TRS_AnimFX_WST050_pSphereC1_TRS_AnimFX_WST050_pSphereD_TR_Anim If yo ...

Open Formats: Interchange Import PIE - Importing static mesh while a PIE session is running permanently breaks nanite on the asset

UE - Editor - Open File Formats - Mar 12, 2025

Importing a Static Mesh during PIE can cause it to never enable Nanite, even if it reports that Nanite is enabled. To re-enable Nanite on the mesh, the asset needs to be deleted and imported again ...