Translucent materials in the PostMotionBlur pass can cause a flickering viewport artefact when using TAA

UE - Graphics Features - Feb 5, 2025

There appears to be a bug relating to rendering multiple windows that can trigger under unknown circumstances. It has been reported on rectangle lights in the forums and on PostMotionBlur materials ...

Static Meshes that are reimported with less materials can lead to map check errors on instances that had overriden materials that require manual cleanup

UE - Rendering Architecture - Feb 5, 2025

StaticMeshActors placed in the world can override the default materials of a static mesh. If the static mesh is then reimported with less materials, the actors maintain references to unused material ...

SDF/Mesh Cards do not follow material settings applied on static meshes.

TM - Core - Feb 4, 2025

Building SDF and Mesh Cards require material properties (2 sided and blend mode) applied on Static Mesh to be known at Static Mesh build time. If not, it may leads to rendering artifacts: Reflectio ...

Each bone scales are improperly applied in the physical animation

UE - Simulation - Physics - Character - Feb 4, 2025

Suggested fix from licensee is : PhysAnim.cpp@339 #if 0 FVector RelPos = RecipScale3D * RelTM.GetLocation(); #else FVector RelPos = (BoneIndex == 0) ? RecipScale3D * RelTM.GetLocation() : Rec ...

FLevelInstanceActorGuid::GetGuid issue in Multiplayer

UE - World Creation - Worldbuilding Tools - Level Instances - Feb 3, 2025

I am doing some runtime manipulation of data layers and I am running into a check failure due to a zero guid in FLevelInstanceActorGuid::GetGuid during multiplayer testing. When I debug FLevelInsta ...

Spline mesh crashing in FRayTracingDynamicGeometryCollection::AddDynamicMeshBatchForGeometryUpdate

UE - Graphics Features - Ray Tracing - Jan 31, 2025

A crash occurs when using ray tracing with spline meshes preceded by the following ensure : Ensure condition failed: NumCPUVertices <= VertexBufferNumElements  File: Engine\Source\Runtime\Renderer\ ...

Foot Placement: Division by 0

UE - Anim - Gameplay - Jan 31, 2025

static FVector PointDirectionPlaneIntersection(const FVector Point, const FVector Direction, const FPlane Plane) { return Point + Direction * ((Plane.W - (Point | Plane)) / (Direction | Plane)) ...

Lumen ignores Landscape Holes (Landscape Visibility) when Hardware Ray Tracing is enabled and Ray Lighting Mode is set to Surface Cache

UE - Graphics Features - Ray Tracing - Jan 31, 2025

Context Lumen is the default global illumination and reflections system. Lumen renders diffuse interreflection with infinite bounces and indirect specular reflections in large, detailed environments ...

Foot Placement: Up vector is not configurable

UE - Anim - Gameplay - Jan 31, 2025

Up vector is not configurable so Foot Placement does support variable gravity cases. ...