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 ...

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 ...

WindDirectionalSourceComponent.h has a meta edit condition that, by referencing an undefined property (bSimulatePhysics), throws an error

UE - Framework - Apr 15, 2025

WindDirectionalSourceComponent.h has a meta edit condition that, by referencing an undefined class property (bSimulatePhysics), throws an error in the logs: LogEditCondition: Error: EditCondition pa ...

Enhanced input user settings file on consoles may behave unexpectedly after login change

UE - Gameplay - Input - Feb 27, 2025

The user settings seem to be initialized incorrectly. I think that this might be because, technically, when you log out and sign back in we might use the same ULocalPlayer in some cases on the conso ...

VisualizeTexture with the BMP flag causes a crash when any mip over mip0 is requested

UE - Rendering - Architecture - Dec 18, 2024

When a mip level higher than 0 is requested in VisualizeTexture, the engine will crash. The root cause appears to be VisualizeTexture.cpp:924, on which an incorrect mip level is used to read a non-m ...

Invalidation panels can retain stale hittest data when caching is disabled/enabled

UE - Editor - UI Systems - Slate - Aug 20, 2024

Changes to the hit test grid of an invalidation panel while caching is disabled won't be respected when caching is reenabled. This can cause interactive widgets such as buttons who were set to colla ...

Exposure compensation curves do not blend

UE - Rendering - Graphics Features - Jun 26, 2024

Requested in https://udn.unrealengine.com/s/question/0D5QP000006g7Px0AI/auto-exposure-various Previously discussed in https://udn.unrealengine.com/s/question/0D52L00004vKeNJSA0/blending-postproce ...

Allowed ranges for the different Exposure Settings in PPV are not consistent

UE - Rendering - Graphics Features - Jun 26, 2024

https://udn.unrealengine.com/s/question/0D5QP000006g7Px0AI/auto-exposure-various Caused by inconsistent usage of ClampMin/ClampMax/UIMin/UIMax in Scene.h Ranges should also be modified based on ...

SpringArmComponent with "Use Camera Lag Substepping" does not handle fluctuating frame rates correctly

UE - Gameplay - Jun 4, 2024

The description of SpringArmComponent's "Use Camera Lag Substepping" option says "sub-step camera damping so that it handles fluctuating frame rates well". However, as noted and explained by a licen ...