Editor freezes when saving a MaterialInstance

UDN users have reported hangs in the material editor when editing specifi material instances. This seems to be a threading bug, as CompileDebugViewModeShaders()  is waiting for a shader compilation ...

FAnimationRuntime::BlendPosesPerBoneFilter() causes an assertive crash when Skeletal Mesh LOD is changed

UE - Anim - Runtime - Nov 1, 2023

The crash occurs from "check(BoneBlendWeights.Num() == NumBones);" This crash occurs when the following conditions are met;The skeletal mesh LOD is changed.The number of bones is difference between ...

Migrating a project from UE5.2 to UE5.3.1, there was a difference in the navmesh generated on HISM

UE - AI - Navigation - Oct 24, 2023

HISM is generated by ConstructionScript Actor is placed on the level and navmesh is generated on top of HISM. In UE5.2, the navmesh was generated without splitting on the HISM. In UE5.3, a break occ ...

Reintroduce UE4 Material Layer drag & drop behavior in UE5

UE - Rendering Architecture - Materials - Oct 19, 2023

This behavior has changed from UE4 to UE5 due to a fix to an unrelated bug ([Link Removed]). Reintroduce the old behavior without causing a regression that reintroduces Ben's fixed bug. ...

Non-existing config file loading could cause memory leak

UE - Foundation - Core - Oct 19, 2023

The cause of this problem is the Engine has code paths which register a new allocated object to Map without deleting the previous object. In the repro project, whenever hitting Space Bar, the level ...

Landscape layers ending with _0, _1, etc. don't work

UE - LD & Modeling - Terrain - Landscape - Oct 19, 2023

Result : only the layer not ending with _0 or _1 will actually render (i.e. Layer0 in the previous example) Expected result : all 3 layers can be painted, no matter their name ...

Material Layers "swap" location instead of shift downwards.

UE - Rendering Architecture - Materials - Oct 17, 2023

Licensee request for this as it is affecting productivity. Likely requires a method of allowing a user to choose which behaviour they prefer. For reference, the behaviour changed in CL 11684461 to f ...

A disabled Niagara component is respawned unexpectedly by scalability system in some edge cases

UE - Niagara - Scalability - Oct 17, 2023

Even after manually Deactivating a Niagara component, this Niagara component may be revived under certain conditions. This issue occurs when the following conditions are met before the Deactivated N ...

[AI] Unable to bind StateTree task input to the properties of an output object.

UE - AI - StateTree - Oct 13, 2023

StateTree no longer binds to the properties of an output variable from a task or an evaluator. Selecting one of the child properties of the output variable results in an error string being displayed ...

Montage Editor calls NotifyEnds of AnimNotifyState even when paused

UE - Anim - Gameplay - Oct 13, 2023

In the Animation Montage Editor, NotifyEnd is unexpectedly called when a time marker is in the middle of an AnimNotifyState and the animation preview gets paused. Because the Animation Montage Edito ...