Collision Drawing in Cooked Builds (Development) doesn't Show Geometry for Nanite Meshes

UE - Graphics Features - Jun 2, 2025

Context The showFlag.CollisionVisibility 1 cvar is a viewport visualization mode that highlights which Actors will block visibility. The showFlag.CollisionPawn 1 cvar is a Player Collision viewmode ...

Local lights appear broken when baking lighting with GPU Lightmass

UE - Graphics Features - Jun 2, 2025

Encountered an issue where local lights appear to be broken when baking lighting with GPU Lightmass. See screenshots attached. Tested regression in //UE5/Release-5.5 @ CL40574608 and the issue does ...

Possible bug with GAOGlobalDistanceFieldCacheMostlyStaticSeparately

UE - Graphics Features - Jun 2, 2025

The Global Distance Field can constantly update, even when the camera is stationary, in large World Partition maps. This bug requires a large amount of the World Partition map to be loaded to reprod ...

StructUtils plugin's `FInstancedStruct` in a CPP-defined struct in a `TArray` on an actor component defined in CPP and implemented in BP. Populating the instanced struct in an actor BP's class defaults breaks serialization of the class defaults.

UE - AI - May 30, 2025

Context Instanced structs are great for holding simple data with the main advantage they have is a low memory overhead unlike instanced objects. Problem The problem is in StructUtils plugin's `FIns ...

[5.4+] World Partition Landscape Spline Meshes Builder - Source landscape splines are not properly removed/hidden

UE - World Creation - Worldbuilding Tools - HLOD - May 30, 2025

LandscapeSplineActors and LandscapeSplineMeshesActors are not behaving as expected in 5.4 or 5.5. Testing in 5.4 the issue mostly seems to stem from issues with the Target Landscape -> Landscape Ac ...

Multiple setter functions in UMaterialEditingLibrary always return false even when the parameter is correctly set on the MaterialInstance.

UE - Rendering Architecture - Materials - May 30, 2025

In Unreal Engine, materials can expose parameters that can then be modified via instances (MaterialInstanceConstant). The UMaterialEditingLibrary provides several functions to modify these parameter ...

TSR and TAA history accumulation gets reset when taking viewport screenshots or when clicking outside the tree in the outliner

UE - Graphics Features - May 30, 2025

TSR (and TAA) history accumulation gets reset when taking viewport screenshots or when clicking on an empty area in the outliner (when a tree item is selected). This can cause an undesirable issue w ...

GLTFExporter indexing issue

UE - Editor - Content Pipeline - glTF - May 29, 2025

Hi, I also ran into an issue when exporting a skeletal mesh that has multiple sections that all share the same material slot. It looks like the index buffer that's constructed is incorrect. In GLTF ...

GPU Lightmass no longer works with cascaded shadow maps

UE - Graphics Features - May 29, 2025

Since Unreal Engine 5.5 stationary lights have stopped working with GPU Lightmass when using Cascaded Shadow Maps. With Virtual Shadow Maps enabled on the project, GPU Lightmass works. This issue d ...

Live Link Hub hang when discovering YUV444 encoded takes in Capture Manager

UE - Virtual Production - IO - LiveLink - May 28, 2025

When using Capture Manager in Live Link Hub to discover takes which contain video encoded with the YUV444 pixel format will cause the application to hang. The Windows Media Foundation library used ...