Multiple setter functions in UMaterialEditingLibrary always return false even when the parameter is correctly set on the MaterialInstance.

UE - Rendering - Architecture - Materials - May 30, 2025

In Unreal Engine, materials can expose parameters that can then be modified via instances (MaterialInstanceConstant). The UMaterialEditingLibrary provides several functions to modify these parameter ...

Search field in 'Quickly Add to Project' fails with Chinese Pinyin input unless manually focused

UE - Editor - UI Systems - Localization - May 28, 2025

A licensee reported that under the Chinese language setting in UE5, using the “Quickly Add to Project” button results in incorrect or ignored input when entering text via Pinyin IME. If the user sta ...

UAnimSingleNodeInstance doesn't sample notifies on montage animation tracks

UE - Anim - Gameplay - May 27, 2025

Notifies that are placed on animations referenced by montages aren't triggered when using the UAnimSingleNodeInstance to play back the montage. This is because - unlike on UAnimComposite - there is ...

Misaligned sampling in UI Material with with CustomStencil

UE - Editor - UI Systems - 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 ...

Changes to Instanced Properties default value on BP not propagated to placed actors in the opened level

UE - Foundation - May 15, 2025

In UE versions 5.4 and onwards (as of CL 42589677 in Main), when an Instanced UObject property is defined in an Actor Blueprint, modifying the default value in the Blueprint does not propagate the c ...

RayTracingManager::Tick() called twice in a single game frame

UE - Rendering - Graphics Features - Ray Tracing - May 14, 2025

A licensee has shared a project with us, in which they are able to trigger a problematic case where the RayTracingGeometryManager is ticked twice during a single game frame. It would be good to inve ...

WidgetComponent is not updated with occlusion culling disabled

UE - Platform - XR - May 7, 2025

LastRenderTime is never updated with occlusion culling disabled, so the widget component will always stop updating.  (see UWidgetComponent::ShouldDrawWidget) Developers can force updates by TickWhen ...

Animating a bone in Persona when additive curves are present, causes exponential translation

UE - Anim - Runtime - May 5, 2025

If there is an additive curve present with scalar data, and that scalar data is something like 10,10,10. When you attempt to animate the bone again the translation of the widget with translate expon ...

ChaosWheeledVehicleMovementComponent is breaking the const CDO contract and changes to the instances are being applied to the CDO

UE - Simulation - Gameplay - Apr 28, 2025

As described by the licensee, the const CDO contract is being broken on ChaosWheeledVehicleMovementComponent. The issue the licensee is facing is that by spawning cars with different configurations, ...

Fields with Maximum resolution are not affecting all leaves of a Geometry Collection

UE - Simulation - Visual - Apr 25, 2025

Fields with Maximum resolution are not affecting all leaves of a Geometry Collection on 5.4 and onwards. When calling GetRelevantParticleHandles() a Maximum Resolution field does return all particl ...