Niagara Ribbon Facing Mode Custom Side Vector does not work correctly

UE - Niagara - Feb 28, 2020

The Custom Side Vector facing mode is no different than the Custom facing mode on Niagara ribbons. The linked UDN has more information on a potential cause, as well as a proposed fix. It looks like ...

Hidden Shadows Aren't Rendered When Raytracing Is Enabled

UE - Graphics Features - Lumen - Mar 13, 2020

Hidden shadows aren't rendered when ray tracing is enabled. Found in 4.25 Preview 2 CL#12055273 Reproduced in 4.23.1 CL#9631420, 4.24.3 CL#11590370, 4.26 Main CL#12123513 ...

FBX skeletalmesh animation import use an integer for sample rate

UE - Editor - Content Pipeline - Import and Export - Sep 11, 2020

Integer sample rate is not playing well with 23.976(NTSC/24) sample rate, the curve get resample at 30Hz in that case and we loose precision. We need to support FFrameRate sample rate to get accura ...

An array of structures variable has its values reset when the structure is modified without recompiling the blueprint

UE - Framework - Blueprint Compiler - Apr 2, 2021

An array of a structure that has been modified without the array's blueprint being complied results in the values of the array element being reset. Compiling each blueprint that has the array of str ...

Dark square appears in hair in direction of spotlight when shadows disabled

UE - Graphics Features - Sep 18, 2024

A dark square appears in the direction of a spotlight on hair when the spotlight has no shadow. [Image Removed] In UE 5.4 the dark square is visible when the spotlight has no shadow, and a light s ...

No warnings or errors if a UEnum has Bitflags metadata, but no Flags flag.

UE - Framework - Blueprint Compiler - Jan 29, 2025

The problem here isn't obvious: the native enum, EAnotherEnum, is missing the Flags flag for the UEnum. As a result, K2Node_GetEnumeratorNameAsString returns the max enum when it gets a combined fla ...

Additives using Frame From This Animation as the Base Pose Type fail to retarget correctly

UE - Anim - Rigging - Retargeting - Feb 13, 2025

Additive animations that use a frame from their own sequence as a base pose are initially broken when retargeted.  Users have to refresh the properties that select the base pose in order to fix the ...

Actors transforms broken in cooked builds when their parent is an IsEditorOnlyActor

UE - Foundation - Data Pipeline - Cooker - Oct 7, 2025

When creating a hierarchy of Actors in the Outliner, the transform of the "child" actors will be reset if their Parent's IsEditorOnlyActor property is true.  The project in the EPS case is using ...

Changing Texture compression settings breaks Materials with mismatch on Texture Sample Sampler Type

UE - Rendering Architecture - Materials - Aug 5, 2015

If you change a texture's compression settings, materials will show errors because of a mismatch in the Sampler Type of Texture Samples. This can be fixed by adjusting the Sampler Type and re-savin ...

Switching to different modes in the Modes panel causes PIE to take input from a connected VR headset for the Y axis camera movement

UE - Platform - XR - Dec 9, 2016

If a VR headset is connected, it will be used for Y axis camera input in PIE if you have switched to and from the Landscape tab in the Modes panel. You can fix this temporarily by reopening the edit ...