Report of branching point notifies failing to trigger

UE - Anim - Runtime - Nov 15, 2021

The problem seems to come from a notify having its LinkedMontage set to null when RefreshBranchingPointMarkers() is called. IsBranchingPoint() fails in this case, so it's never registered as a branc ...

Landscape nanite height mismatch

UE - Graphics Tools - Terrain - Landscape - Oct 17, 2023

From licensee: The height of Nanite rendered landscape does not match the height of non-nanite landscape. The error gets worse if you increase the Z Scale of the landscape actor. Our project rec ...

Large World Coordinates appears to not work for Niagara Mesh Particles

UE - Graphics Features - Nov 28, 2024

When a Niagara System is placed at around 10^8 units away from the origin, the movements of the mesh particles aren't smooth as expected, but jumpy. These particles behave as if they are using a flo ...

Datasmith & mikktspace tangent cause entities to glow with lightmaps

UE - Editor - Content Pipeline - Datasmith - Exporters - Feb 22, 2019

The steps above are reduced to their simplest expression.  I appears that several customers complained about lightmap baking resulting in glowing objects.  This typically happens on interior door fr ...

Getting Fullscreen or Windowed Resolutions doesn't fully execute on Linux

UE - Rendering Architecture - RHI - Oct 28, 2019

When using "Get Supported Fullscreen Resolutions" on UE when built with Vulkan, no values are printed out. This is an issue with any platform that builds UE with -vulkan, not just Linux.  In Engine ...

UPoseAsset::SetBasePoseName() always sets INDEX_NONE

UE - Anim - Runtime - Apr 11, 2025

UPoseAsset::SetBasePoseName() does not correctly set the BasePoseIndex when a valid pose name is provided. Regardless of input, the pose defaults back to ReferencePose. Upon inspection of the implem ...

StreamableManager does not apply CoreRedirects to loaded paths

UE - Framework - Jun 12, 2025

When loading soft object paths directly, it applies any important CoreRedirects by calling the function FixupCoreRedirects if the initial load attempt fails. In the repro steps, this will apply this ...

WorldCoordinate3Way produces Incorrect Axis Lerps

UE - Graphics Features - May 18, 2016

The Material Function WorldCoordinate3Way seems to incorrectly perform the Lerps from the axis contributions of the normals. An example is show here, with the left objects using the version that com ...

GPU / D3d Crash while editing Landscapes

UE - Graphics Tools - Terrain - Landscape - Mar 7, 2023

From licensee: I've been experiencing consistent GPU crashes when tying to edit landscapes since updating to UE5.1. It seems to be exclusively an issue with DirectX 12 (SM5 & SM6). I have no pro ...

In UInstancedStaticMeshComponent, when some instances have near-zero scale, removing instances crashes the engine

UE - Rendering Architecture - Oct 19, 2023

Class "UInstancedStaticMeshComponent" deliberately leaves null pointers in the "InstanceBodies" array of FBodyInstances. This can be seen in methods such as: [Engine\Source\Runtime\Engine\Private\I ...