Material Layers Ignore Virtual Texture Sampler Restrictions

UE - Rendering Architecture - Mar 25, 2024

Virtual Textures can be assigned to Texture Sample Parameters that are not configured for Virtual Textures, if that parameter is inside of a Material Layer. Also found in Release-5.4, CL 32426910 ...

Translucency area has stripe-style issue on TSR

UE - Graphics Features - Mar 28, 2024

The TSR History Rejection buffer develops a grid-like artifact over translucent, camera-facing planes. ...

When a Niagara User Parameter is renamed, mesh bindings on Niagara Mesh Renderers are not updated, and the binding is silently broken

UE - Niagara - Mar 13, 2025

In Niagara, Mesh Renderers expose a "Meshes" array for selecting the meshes to be rendered. On each array entry, a property "Mesh Parameter Binding" is available and allows the user to override that ...

Duplicating an actor with a blueprint bound delegate behaves unexpectedly

UE - Gameplay - Blueprint - Aug 15, 2022

When the trigger is duplicated, the contents of its OnActorBeginOverlap MC delegate are copied, which contains a reference to the BP actor that added the binding to the original trigger. Marking th ...

During blueprint reparenting SimpleConstructionScript subobject unmodified values are retained as modified values

UE - Framework - Blueprint Editor - Nov 27, 2024

When reparenting blueprints and both the old and new parent blueprint contain a subobject but with different values on it, the reparented blueprint doesn't correctly inherit values from the new pare ...

Input Actions bound to Any Key become unresponsive after mouse scroll until scrolled again

UE - Gameplay - Input - Mar 28, 2025

In UE latest release (5.5 launcher version), Enhanced Input Actions mapped to "Any Key" stop responding after scrolling the mouse wheel. Specifically, scrolling either up or down disables the Any Ke ...

Actor attached to child actor fails to serialize as part of map

UE - Framework - Components - Nov 3, 2023

Attaching other actors to a child actor (actor spawned by ChildActorComponent) fails to serialize correctly as part of the map. The attached actor loads as detached and resets its position back to w ...

UV Offset Effect Material in RetainerBox Causes Visual Artifacts in Editor Preview

UE - Editor - UI Systems - UMG - Apr 22, 2025

When a UV Offset is applied in a RetainerBox effect material, visual artifacts appear only in the editor — not at runtime — if a widget with a dotted preview outline (like CanvasPanel) is placed dir ...

Stale VSM pages after HLOD transition

UE - Graphics Features - Shadows - May 23, 2024

Virtual Shadow Maps do not invalidate pages when HLODs replace meshes. This can lead to inconsistencies between the geometry and the shadows, which can cause artifacts as pages are invalidated. ...

Placed level instance causes "!ActorInstanceGuid.IsValid()" assertion after changing WorldSettingsClass

UE - World Creation - Worldbuilding Tools - Level Instances - Nov 13, 2023

Resaving the level using ResavePackagesCommandlet is a workaround. ...