Unreal Engine Issues

Crash in NaniteStreamManager when Nanite data fails to decode corrupt data from DDC

If Nanite data becomes corrupt in the DDC, the Editor may crash in FStreamingManager::InstallReadyPages() when the Pending.State is FPendingPage::EState::DDC_Ready but the resulting SrcPtr is null b ...

Assert in MoviewPipelinePIEExecutor when cancelling movie scenes during rendering

When rendering a single Level Sequence with MRQ, removing the Level Sequence that is actively rendering will create an array out of bounds exception. Also confirmed in //UE5/Main, CL: 36086643 ...

Creating an HLOD with a FallbackMesh that has a section with triangles=0 will incorrectly set the UVs of the StaticMesh

The UVs in HLOD's StaticMesh appear to be broken when there are sections with zero triangles in the fallback mesh. This is most likely the case for sections containing only small parts. Workaroun ...

Unreal Editor 5.4.4 crash when reproducing a LevelSequence in loop while PIE.

A crash inside Unreal Engine Editor version 5.4.4 occurs when reproducing a Level Sequence while in PIE. This issue is a regression. It only crashes in version 5.4.4. It was working correctly in ver ...

Actor blueprint 'bOptimizeBPComponentData' breaks subobject instantiation for runtime spawned actors in cooked builds

A user has reported that when an actor blueprint enables Generate Optimized Component Blueprint Data, default instanced objects of components are not properly duplicated in cooked builds. This resul ...

Message to rebuild lights does not display after static mesh position has changed

In a static lighting environment, moving static objects no longer marks the built lighting as invalid. This prevents the on-screen warning from appearing. Regression introduced in CL: 25964466 on / ...

Material Layering sometimes increses Shader complexity significently

Nanite meshes are lit differently in Actor Colorization view modes than non-Nanite meshes

When the Lit > Actor Coloration > Affects Navmesh or other Actor Coloration mode is used, Nanite meshes apply lighting differently than non-Nanite meshes which can make it difficult to use the Actor ...

Material instance UI doesn't show correct parameter preview for logic in a material function

The Material Instance UI doesn't show the correct parameter values when the logic is moved from the material graph into a material function used in that material graph. Example setup showing the wr ...

BlendListByEnum assumes that enum values are sequential

FAnimNode_BlendListByEnum assumes that values within a custom enum type are sequential (ie. the index 0 = value 0, index 1 = value 1).  But this is not true of all custom enum types, for example: U ...