Bundled compute PSO compilation stalling tender thread

UE - Rendering Architecture - RHI - Feb 13, 2025

EA Motive has pointed out a potential bug they found related task graph synchronization and when compiling compute PSOs: [Link Removed]. From the screenshot they sent over, it seems that a task grap ...

Cards for a Groom asset do not update normals during simulation

UE - Graphics Features - Feb 13, 2025

When a groom is allowed to simulate, only the strand representation computes correct world normals for the new hair strand positions. This is especially noticeable when the groom is inverted as grav ...

D3D12 Does Not Correctly Validate Static Uniform Buffers Correctly

UE - Rendering Architecture - RHI - Feb 12, 2025

When adding a Uniform Buffer Struct that has one 4x4 matrix to a mesh pass, validation will fail, due to a Uniform Buffer Struct mismatch. This can be reproduced by adding a mesh pass in project-si ...

5.4, FRHIMemoryPool leaks memory

UE - Rendering Architecture - RHI - Feb 12, 2025

FRHIMemoryPool will leak data when it is destroyed. "FRHIMemoryPool::Init()" will create "FRHIMemoryPool::DesiredAllocationPoolSize" new "FRHIPoolAllocationData" objects, stored in "FRHIMemoryPool: ...

FCableSceneProxy::BuildCableMesh thrashes memory allocator

UE - Simulation - Physics - Feb 12, 2025

FCableSceneProxy::BuildCableMesh in CableComponent.cpp:233 showed up as a hot spot in profiling because the two TArray allocators in SetDynamicData_RenderThread used by BuildCableMesh are created an ...

Incorrect mesh deformation when Max World Position Offset Displacement used

UE - Graphics Features - Nanite - Feb 12, 2025

When Vertex Animated Texture is used to animate a mesh with World Position Offset, often the Max World Position Offset Displacement Material setting must be increased or the Bounds Scale increased, ...

Iris - incorrect initial state in pawn's BeginPlay if replicated via huge object path

UE - Networking - Iris - Feb 11, 2025

This occurs when the pawn is initially replicated using the huge object path when first connecting to a server. Destroying and restarting the client's pawn works as expected. After connecting, the c ...

World Partition grid priority setting taken into account last

UE - World Creation - Worldbuilding Tools - World Partition - Feb 11, 2025

From licensee:Editor Grid priorities setting will get overruled in code giving the user false feeling of control – smaller grid cells can load before larger grid cells on the same layer even if the ...

Mover ensure triggered when engine is running in the background

UE - Gameplay - Player Movement - Mover - Feb 11, 2025

When the engine is running in the background, the following ensure may be hit in NetworkPredictionService_Interpolate.inl: npEnsure(ToFrame == INDEX_NONE || LocalFrame - ToFrame < Frames.Buffer.Cap ...

Backwards-compatibility broken for the CDOs of Python-generated Unreal Types because of missing redirectors

UE - Editor - Workflow Systems - Feb 11, 2025

Previously, all Unreal Types generated by python scripts would be created inside package "/Engine/PythonTypes". This was changed by [CL 32478991 in ue5-main branch], which meant to "remove the restr ...