Calling UBlueprintMapLibrary::GenericMap_Find with a non-existent key causes a memory leak

When Calling UBlueprintMapLibrary::GenericMap_Find with a non-existent key, the function construct the default structure in-place on the given pointer without destroying the object. This behavior ca ...

FName no longer equals FName_None when constructed with a trailing underscore and digits in range of 1-9

When an FName is created with a trailing underscore and any number of digits in the range of 1-9 the trailing digits are used as the internal number value for the FName lookup. This results in the F ...

Inconsistent parameter handling for pak/iostore block size / patch padding

UE - CoreTech - IoStore - Apr 14, 2025

Users have trouble overriding the blocksize/patchpaddingalign parameters for UnrealPak from UAT commandlines.There is no easy way to specify these parameters through a buildcookrun, instead they n ...

Landscape raytracing geometry always updates every frame

UE - Graphics Features - Ray Tracing - Apr 11, 2025

LOD 0 Landscape meshes are always updated in FLandscapeComponentSceneProxy::GetDynamicRayTracingInstances because* r.RayTracing.Geometry.Landscape.LODsUpdateEveryFrame* (GLandscapeRayTracingGeometry ...

UPoseAsset::SetBasePoseName() always sets INDEX_NONE

UE - Anim - Runtime - Apr 11, 2025

UPoseAsset::SetBasePoseName() does not correctly set the BasePoseIndex when a valid pose name is provided. Regardless of input, the pose defaults back to ReferencePose. Upon inspection of the implem ...

Nanite TwoSidedSign is backwards

UE - Graphics Features - Nanite - Apr 10, 2025

The value of MaterialExpressionTwoSidedSign is flipped when calculating the Opacity Mask for Nanite meshes. This seems to be a regression in 5.5. ...

XR - Volumetric Clouds - VM Clouds appear overtop of meshes in the right-eye

UE - Graphics Features - Apr 10, 2025

When the user changes the Volumetric Render Target Mode, the Volumetric clouds in a scene will render in front of Static Meshes in the Right-Eye. ...

[CrashReport][Crash] UnrealEditor-Core!IMemoryReadStream::CopyTo()

UE - Rendering Architecture - Apr 10, 2025

Intermittent crash in virtual texture transcode. Usually mempy from nullptr but also occasionally we see the same callstack with memcpy to random location. ...

Investigate PythonScriptPlugin module load order for preload module

UE - Editor - Workflow Systems - Apr 10, 2025