Color shifting occurs from screen probe gather ping-pong when Lumen active

UE - Graphics Features - Lumen - Apr 29, 2024

A subtle yellow tint color shift occurs when Lumen is active due to usage of R11G11B10_Float targets, mostly from r.Lumen.ScreenProbeGather.SpatialFilterProbes where we ping-pong between R11G11B10_F ...

GPU Crash in Niagara Fluids template when WorldSpaceSize has a component at 0

UE - Niagara - Apr 26, 2024

The NiagaraFluids plugin provides several Niagara System templates to use as a starting point for the user's own Systems. The templates in category "3D Gas", such as "Grid 3D Gas Explosion", include ...

GameplayTagQuery in editor can fail to update to new values or reset after being cancelled

UE - Gameplay - Apr 25, 2024

When editing a GameplayTagQuery inside of the editor, there are times when the query editor will not update the query when selecting Ok or fail to return the query to its original state before editi ...

Masked TwoSided material causing lumen direct lighting to leak through walls

UE - Graphics Features - Lumen - Apr 23, 2024

It appears that LumenScene's Hardware Ray Tracing is causing light leaking into a sealed room (which should be perfectly black). This bug does not appear to happen on AMD GPUs. ...

Using "Change Class" on Spawnables, Possessable references retain old Class info

UE - Anim - Sequencer - Apr 22, 2024

Changing Class for Spawnable objects in Level Sequence did not have any impact on Possesable objects in Subsequence. It's still referencing the previous Class. Also found in Release-5.4, CL: 329753 ...

Unable to Create New Niagara User Parameter After Deletion without Niagara Editor Window Restart

UE - Niagara - Scripting - Apr 22, 2024

When a user deletes a Niagara User Parameter within the Niagara System editor window, attempting to create a new parameter with the same name immediately after deletion results in an error. Despite ...

Blueprint Add Custom Event unable to resolve delegate signature inside a split struct

UE - Gameplay - Blueprint - Apr 19, 2024

This issue occurs when a static function is created and has a struct parameter that has a delegate exposed to blueprint. When using the helper function in blueprint after having used "Split Struct ...

Changes to Instanced Properties on a BP archetype are not propagated to Actors inside Level Instances or unloaded levels.

UE - Gameplay - Blueprint - Apr 19, 2024

Consider a C++ ActorComponent containing an instanced TObjectPtr property (which may be standalone or inside a container such as TMap). Now consider a Blueprint Actor containing such a component, an ...

Moving noise is visible in hair shadows when Lumen screen traces are active

UE - Graphics Features - Apr 18, 2024

Dark moving noise is visible in hair in the shadows when Lumen screen traces are active.  Example of noise when screen tracing is frozen:[Image Removed] Turning off Lumen screen traces using r.Lume ...

ExportMaterialUVDensities() gets the incorrect value where the alpha channel is referenced

UE - Rendering Architecture - Materials - Apr 16, 2024

ExportMaterialUVDensities() gets the incorrect value where the alpha channel is referenced (e.g. RegisterIndex of the texture is [3] or [7]) because FMeshRenderer::RenderMaterialTexCoordScales() use ...