Mirror operation on Physics Asset produces wrong results for constraints, including flipped axes

UE - Simulation - Physics - Feb 7, 2025

The Physics Asset Editor has a "mirror" feature that allows physics bodies and constraints to be mirrored from one side of a skeleton to the other. If this operation worked correctly, it could save ...

Sphere Reflection Captures overridden by Skylight

UE - Graphics Features - Jun 10, 2025

When using non-Lumen lighting and Screenspace reflections off, the skylight location overrides the Reflection Capture location during Build Reflections. This results in a Reflection Capture taken fr ...

Pasting timeline components into another actor and then choosing "cancel" on fix self context function references results in a broken state

UE - Framework - Components - Sep 13, 2021

upd. Regression was checked on //UE4/Release-4.26 CL 15973114, issue was reproduced. Regression - No ...

LandscapeSplineMeshesActor instances not deleted when World Partition is disabled

UE - World Creation - Worldbuilding Tools - World Partition - Oct 30, 2024

When landscape splines exist in a WP level, LandscapeSplineMeshesActor instances are created to allow streaming of splines. In a non-WP level, splines are components of the landscape actor. When a W ...

It is possible for PreLoadScreen to leak memory when an EngineLoadingScreen returns IsDone while still loading

UE - Graphics Features - Jan 9, 2025

It is possible for a class that implements IPreLoadScreen to leak memory if GetPreLoadScreenType returns EngineLoadingScreen and IsDone returns true before the engine signals loading is completed vi ...

Opcode shader compilation error when using a TextureSampleParameterCubeArray node with hardware ray tracing enabled

UE - Graphics Features - Ray Tracing - Mar 31, 2025

Materials containing a cube array texture sampling node will not compile when hardware ray tracing is enabled. The shader compilation error indicates that an invalid op code was used: "Opcode Sample ...

Natively declared Gameplay Tags aren't counted by Reference Viewer when set default by ctor

UE - Gameplay - Jul 11, 2024

Similar to Issue 199247 ([Link Removed]), Natively declared Gameplay Tags aren't counted by Reference Viewer when used in a variable set in a C++ ctor. ...

Discrepancy in FBX import on animations

UE - Editor - Content Pipeline - FBX - Mar 19, 2025

In the attached screenshots, the following Animation Sequence assets are wrong: * FX_WST050_pSphereB1_TS_AnimFX_WST050_pSphereC1_TRS_AnimFX_WST050_pSphereC1_TRS_AnimFX_WST050_pSphereD_TR_Anim If yo ...

Arrays in UMaterialEditorInstanceConstant are not updated

UE - Rendering Architecture - Materials - Jun 13, 2025

Any UPROPERTY TArray added to UMaterialEditorInstanceConstant will not cause UI updates when elements are added or removed. This is caused by the custom validator created in FMaterialInstanceEditor ...

Volumes visible on screen cannot be selected with box selection if "Box Select Occluded Objects" is enabled

UE - Editor - Workflow Systems - May 22, 2024

When using box selection with "Box Select Occluded Objects" enabled, volumes in the box selection zone are not able to be selected. ...