Nanite Skeletal Mesh uses incorrect LOD for raytracing

UE - Graphics Features - Nanite - Jan 13, 2025

LOD0 for some Nanite Skeletal meshes is used for ray tracing scenes on some platforms  because some FSkinnedSceneProxy are incorrectly considered "always visible" ...

Regression - Nav mesh is not generated on BSP brushes after loading a map

UE - AI - Navigation - Jan 14, 2025

In UE 5.5, when loading a map and selecting "Build – Build Paths", the nav mesh is not generated on any BSP brushes (although it is correctly generated in static meshes). This did not happen in earl ...

Navigation: Exiting game while async nav building tasks are running can cause null pointer access of OctreeController.NavOctree from worker thread

UE - AI - Navigation - Jan 14, 2025

Context Projects can turn on the project setting bDoFullyAsyncNavDataGathering to execute navigation mesh building tasks on worker threads. Some of these tasks will access the NavOctree, whose life ...

GPU Crash from invalid SRV in CreateShaderResourceView due to integer underflow

UE - Graphics Features - Ray Tracing - Jan 13, 2025

The GPU crashes after the ray tracing geometry builder attempts to create a shader resource view with an invalid offset. ...

Keying Level Sequence Crashes Engine

UE - Anim - Sequencer - Dec 12, 2024

Repro rate 3/5 Regression to be tested Testing with a fresh level sequence no crash occurs, Tried to do it without rekeying and did not get a crash. I repro'd it a few times and sometimes no crash ...

Substrate Add node only adds the first Substrate Slab's Emissive value when "Use Parameter Blending" is enabled

UE - Graphics Features - Substrate - Jan 10, 2025

As per the steps to reproduce, the Substrate Add node only adds the first Substrate Slab's Emissive value when "Use Parameter Blending" is enabled. Leaving "Use Parameter Blending" unchecked on the ...

SSourceControlChangelistsWidget : hitting the checkf for duplicate uncontrolled items in OnRefreshUncontrolledChangelistWidgets

UE - Editor - Workflow Systems - Dec 18, 2024

A checkf can fail in SSourceControlChangelists.cpp with the message: The same uncontrolled item was visited twice. It is likely present in more than one uncontrolled changelist This has been addre ...

Iris - Non-replicated properties of FInstancedStruct reset after replication

UE - Networking - Iris - Nov 8, 2024

This issue only occurs with Iris enabled. ...

Translucency Volume are not correctly shadowed in 5.5 without Virtual Shadow Maps and are not light correctly by some lights

UE - Graphics Features - Dec 20, 2024

TranslucencyVolume spheres are not correctly shadowed nor lit in Unreal 5.5 with VSMs disabled. Unreal 5.4 does correctly shade the sphere without VSMs. There appears to be differences in the outpu ...

Instanced object in an array property of an actor component is invalidated and marked for garbage collection on undo

UE - Gameplay - Jun 4, 2024

If an actor component contains a TArray of instanced objects, some of those object instances can get incorrectly invalidated and marked for garbage collection in certain situations, possibly resulti ...