Duplicated PCG Component instance resets overridden parameters to default

UE - Graphics Tools - PCG - Components - Jun 4, 2025

Context: Similar to parameters in the Material editor, PCG Graph Parameters are user created overridable values and can help create customizable graphs for a variety of situations. Problem: The l ...

Toggling a Spline component from an open/closed loop through bp's isn't reflected

Tools - Jan 19, 2015

Toggling a Spline component from an open/closed loop through bp's isn't reflected ...

Some post-processing passes sample outside of the viewport when using scene capture components

UE - Rendering - Graphics Features - Nov 29, 2023

It looks like the SSAO shader does not clamp its sample space to the half view size for the two inputs "Ambient Occlusion" and "AmbientOcclusionSetup", leading to invalid data entering the edge of f ...

Blueprint - Crash when a function takes an event as a parameter

UE - Gameplay - Blueprint - Oct 10, 2016

Looks like maybe we aren't replacing the source delegate function (SignatureFunction) reference on the UDelegateProperty after recompiling the class - the function's owner name has the TRASHCLASS pr ...

FileSystemDerivedDataBackend may output a corrupted access log

UE - Foundation - Core - Derived Data - May 20, 2021

This problem is caused by the AccessLogWriter has not been flushed at the termination. The following workaround flushes the Writer.class FFileSystemDerivedDataBackend : public FDerivedDataBackendInt ...

Hot reload breaks code based struct array used in blueprints

UE - Gameplay - Blueprint - Mar 21, 2016

When an array of a struct, defined in code, is used in a blueprint, preforming a hot reload after making changes to the class with the struct will cause the blueprint nodes relating to the struct be ...

Destructible Mesh component doesn't show in bp viewport until the bp is reopened

UE - Simulation - Physics - Destruction - Jun 10, 2016

Destructible Mesh component doesn't show in bp viewport until the bp is reopened User Description: Mesh dont appears in viewport after add DestructibleComponent and set "Destructible Mesh". After ...

Environment Query System (EQS): EnvQuery runtime template object can be created with a non-unique name, corrupting the EnvQueryManager cache

UE - AI - Aug 5, 2025

On file [Engine\Source\Runtime\AIModule\Private\EnvironmentQuery\EnvQueryManager.cpp:812], function UEnvQueryManager::CreateQueryInstance() uses StaticDuplicateObject() to create a new UEnvQuery* (d ...

PlayerController::PlayDynamicForceFeedback called through code does not fire

UE - Gameplay - Input - Feb 25, 2016

Calling PlayDynamicForceFeedback in code does not affect controller rumble. ...

Custom Time Dilation causes PhAT bodies to hover

UE - Simulation - Physics - Nov 5, 2015

Custom Time Dilation causes PhAT bodies to hover This is not only happening with vehicles like the original bug described. This is also happening with PhAT skeletal meshes that are moving. https:/ ...