Linear interpolation occurs on constant tangent curve partially

UE - Runtime - Animation - Feb 17, 2025

When using UV scrolling for a flipbook-like animation in Animation Sequence, creating keys with "Constant Tangent" settings on Curve Editor does not result in an instantaneous change to the specifie ...

Ambient occlusion causing ghosting for animations when viewport is resized on DX11

UE - Rendering - Graphics Features - Feb 10, 2025

Tested regression against //UE5/Release-5.4 @ CL35576357 and the issue did not occur. This is a confirmed regression.[Image Removed] Jira Bot attaches conversation thread from Slack [Image Removed]D ...

Interchange Import - Import model with custom collision prevents socket to be imported

UE - Editor - Open File Formats - Feb 5, 2025

I would like parity with legacy: 1) only one material 2) socket to be imported Box_Socket file imports same in legacy and interchange: it is just box and socket without collision. ...

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

UE - Rendering - 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 ...

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

UE - Rendering - 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 ...

UEditorEngine::AddPendingLateJoinClient checks original PIE/SIE state, not current state

UE - Networking - Jan 27, 2025

When adding late joining clients, the engine checks the originally requested EPlaySessionWorldType, rather than checking whether or not the session is currently simulating or not. This means if the ...

Skeletal Mesh motion vector are output only for the last sample of Spatial Sample Count

UE - CAPT - Color Pipeline and Rendering - MRQ - Jan 24, 2025

Skeletal Mesh motion vectors are output only for the last sample of Spatial Sample Count, while Static Mesh motion vectors are output in all samples. UDN: [Link Removed] Slack thread: [Link Remo ...

Steam Sockets cannot create listen socket during non-seamless server travel

UE - Online - Jan 24, 2025

This seems to occur because the original listen socket is still around when the instance tries to create the new one, even though it has been marked for deletion. The issue does not occur when FStea ...

When a TSoftObjectPtr pointing to a const type is used as a parameter for a Dyanmic delegate, unreal marks it as deprecaded.

UE - Core - Cpp Tools - UnrealHeaderTool - Jan 21, 2025

A change has been done to the TSoftObjectPtr class that warns when constructing a pointer-to non-const from a pointer-to-const. This change makes sense and is correct. Example: UTexture2D* Loade ...

Disabling bLerpUVs in Nanite Settings of Static Mesh causes texture warping in clusters

UE - Rendering - Graphics Features - Nanite - Jan 21, 2025

The licensee has identified a potential fix by changing if( Settings.bLerpUVs ) to if( Settings.bLerpUVs || UVIndex == 0 ) On line 389 of NaniteBuilder\Private\Cluster.cpp in UE 5.5 ...