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 - Physics - 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, ...

Chaos Trailing Events not exposed to Blueprints and only accessible via Niagara Chaos DI

UE - Simulation - Physics - Destruction - Apr 22, 2025

Chaos Trailing Events not exposed to Blueprints and only accessible via Niagara Chaos DI. The licensee noticed that the Trailing event is not available to BPs. It's expected that the same data avail ...

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 ...

Inconsistent parameter handling for pak/iostore block size / patch padding

UE - CoreTech - IoStore - Apr 14, 2025

Users have trouble overriding the blocksize/patchpaddingalign parameters for UnrealPak from UAT commandlines.There is no easy way to specify these parameters through a buildcookrun, instead they n ...

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 ...

Modifying the properties of a ChildActorComponent in a child blueprint can modify the parent actor ChildActorComponent properties.

UE - Framework - Blueprint - Dec 10, 2024

When a property of a ChildActorComponent is modified in a child class, the parent ChildActorComponent class can also get modified. This happens when the Parent blueprint actor has a ChildActorCompo ...

Users are unable to create projects when the default project location is a networked drive

UE - Editor - Workflow Systems - Oct 23, 2024

There have been multiple reports of this issue, particularly from schools, over the last 10 years:https://forums.unrealengine.com/t/invaild-folder-path-with-network-user-drives/283475https://forums. ...

CharacterMovementComponent - Jump incorrectly simulated when moving against a wall, resulting in an apex height lower than expected and framerate-dependent

UE - Gameplay - Player Movement - Jun 17, 2024

The CharacterMovementComponent simulates the position of a jumping/falling character inside function UCharacterMovementComponent::PhysFalling() [CharacterMovementComponent.cpp:4381]. On the main cod ...

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 ...