Unreal Engine Issues

AutoSize triggers ensure on shortened Skel Anim Section moved past anim length

In Sequencer, calling "Edit > Auto Size" on a UMovieSceneSkeletalAnimationSection triggers the LowerBound > UpperBound ensure in UMovieSceneSection::SetRange (MovieSceneSection.h:333) when the secti ...

StreamingGeneration: Actor desc mutator phase now writes ActorDescView directly, breaking the cluster-invariant check in ValidateContainerInstanceDescriptors

This report is from an EPS case: We hit a regression upgrading our project from 5.7 to 5.8. Map Check (and any other path that ends up calling UWorldPartition::CheckForErrors) assert inside FWorld ...

FNiagaraRendererMeshes::GetDynamicRayTracingInstances(...) corrupting GPUScene when rendering multiple views

When rendering a game in splitscreen using Lumen HWRT, Nanite and a large number of Niagara Mesh Particles 1mil+, various meshes and actors will stop rendering. Setting r.RayTracing.Geometry.Niagar ...

iOS builds fail on Windows.

Loading Windows installed iOs mobile provisioning profiles fails at start of iOS build from windows machine. This due to a recent change that attempts to load PKCS12 from mobileprovision files. Thes ...

Visibility track key value is no longer the inversion of the bound bHidden property

Regression introduced in UE 5.7. Works correctly in UE 5.6. Up to UE 5.6, the bool value written to the Visibility track's BoolCurve was the inversion of the underlying bound property (e.g. AActor: ...

Blueprints: ComponentClass override causes crash on loading maps with instances saved with base class

Context In actor blueprints, you can change an inherited component’s class in the editor by selecting it in a child blueprint and changing its Component Class in the Details panel. Problem When o ...

Megalights support for anisotropic materials

A licensee noticed that SUPPORTS_ANISOTROPIC_MATERIALS is not passed to FShadeLightSamplesCS::ModifyCompilationEnvironment for MegaLights ShadeLightSampleCS. Adding it fixes the issue. ...

CharacterMovementComponent boosted upward when falling into acute-angle sloped corner

In UCharacterMovementComponent::TwoWallAdjust, characters can gain unintended upward velocity (slope boosting) when hitting corners with an acute angle (<=90 degrees) while in the Falling movement m ...

Niagara System is causing Application SpaceWarp to get disabled

Raytraced Hair Lighting using Light Functions atlas and positions the Light function material doesn't render correctly

Light functions don’t render on grooms when using ray traced shadows and positions in the light function material. The setup:A light (point/rect/spot) pointing to a groom hair system. The light's ...