Conflict between sequencer transform track and Parent Constraint from the Animation Mode breaks temporary pivot translation on any actor

UE - Anim - Anim in Engine - Jul 15, 2025

Note: This affects all versions from at least UE 5.3, including mainline latest. The "Animation" Editor Mode allows creating constraints for level actors. One of these, the "Parent" constraint, con ...

Channel Mask Parameter does not correctly pull through the Alpha channel from

UE - Rendering - Architecture - Materials - Jul 8, 2025

The ChannelMaskParameter node in the Material Graph works in most cases, but unusually does not work when extracting the value of the Alpha channel only for Vertex Color input data. ...

Incorrect UV coordinates when visualizing mesh painting texutre on Nanite splines

UE - Rendering - Graphics Features - Jun 30, 2025

The UV coordinates for visualizing the mesh painting texture on Nanite spline meshes are not working correctly. This runs the code in the NANITE_VISUALIZE_MESH_PAINT_TEXTURE section in NaniteVisuali ...

Sphere Mask ArgInvHardness missing multiplication

UE - Rendering - Architecture - Materials - Jun 27, 2025

Hi Epic, In MaterialExpressions.cpp UMaterialExpressionSphereMask::Compile(), hardness is not calculated the same way in both <if> conditions. One is missing a multiplication by 0.01f. Specificall ...

p.NetShowCorrections debug capsules do not match character's orientation with custom gravity direction

UE - Gameplay - Player Movement - Jun 25, 2025

This looks to be because the debug drawing uses FQuat:Identity for the capsules, rather than the character's orientation. ...

Niagara mesh particles invalidate lighting when "Cast Shadow" is enabled with Hardware Ray Tracing enabled

UE - Rendering - Graphics Features - Lumen - Jun 24, 2025

Lumen HWRT, combined with Niagara Mesh Renderer, can cause the Lumen Scene to be reset, resulting in a sudden change to indirect lighting. ...

GPU event descriptions are not properly formatted in Insight

UE - Rendering - Architecture - RHI - Jun 24, 2025

Context Unreal Insights displays Timing Insights that can include GPU timing information. Rendering code such as FDeferredShadingSceneRenderer::RenderPrePass() generate such events.Problem Certain f ...

FAnimMontageInstance::SetNextPositionWithEvents can trigger all notifies on a montage/sequence

UE - Runtime - Animation - Jun 24, 2025

This issue happens when Sequencer loops a dynamic montage. FAnimMontageInstance::ForcedNextFromPosition is set to 0 and ForcedNextToPosition is effectively the delta time. However, FMontageSubStep ...

Eye Adaptation Inverse node does not work with volumetric materials

UE - Rendering - Graphics Features - Jun 23, 2025

The EyeAdaptionInverse node works differently for surface materials and volumetric materials. In surface materials, it allows to have a consistent glow during day and night time, however in a volume ...

Change uses of "OnlineSubsystemSteam" module name

UE - Online - Jun 19, 2025

The refactor at CL 39638561 moved some classes, such as SteamNetDriver and SteamNetConnection, from the "OnlineSubsystemSteam" module to the new "SocketSubsystemSteamIP" module. There are still a f ...