Nanite UV switch seams

UE - Graphics Features - Jun 13, 2025

Analytical Derivatives are not calculated properly when using UMaterialExpressionSwitch. Disjoint UVs in screen space result in large jumps in the derivatives, which can cause artifacts as the wrong ...

Anim State Notifies Don't Consistently Fire Begin/End Events for Looping Anim Sequences

UE - Anim - Runtime - Anim Blueprints - Jun 9, 2025

If you have an Animation Notify State and set it up on an animation to start at the exact beginning of the anim sequence and finish exactly at the end (I have attached a picture of this). It doesn't ...

Duplicated PCG Component instance resets overridden parameters to default

UE - World Creation - Procedural Tools - PCG Graph - Jun 4, 2025

Context: Similar to parameters in the Material editor, PCG Graph Parameters are user created overridable values and can help create customizable graphs for a variety of situations. Problem: The l ...

Collision Drawing in Cooked Builds (Development) doesn't Show Geometry for Nanite Meshes

UE - Graphics Features - Jun 2, 2025

Context The showFlag.CollisionVisibility 1 cvar is a viewport visualization mode that highlights which Actors will block visibility. The showFlag.CollisionPawn 1 cvar is a Player Collision viewmode ...

Possible bug with GAOGlobalDistanceFieldCacheMostlyStaticSeparately

UE - Graphics Features - Jun 2, 2025

The Global Distance Field can constantly update, even when the camera is stationary, in large World Partition maps. This bug requires a large amount of the World Partition map to be loaded to reprod ...

[5.4+] World Partition Landscape Spline Meshes Builder - Source landscape splines are not properly removed/hidden

UE - World Creation - Worldbuilding Tools - HLOD - May 30, 2025

LandscapeSplineActors and LandscapeSplineMeshesActors are not behaving as expected in 5.4 or 5.5. Testing in 5.4 the issue mostly seems to stem from issues with the Target Landscape -> Landscape Ac ...

Synthetic Benchmark Giving Inconsistent Results

UE - Rendering Architecture - RHI - May 27, 2025

A licensee has noted that the synth benchmark has been giving inconsistent results when they try to find optimal scalability settings for their application. The root cause of this is unclear, but lo ...

Compilation error with Evaluate Chooser node when getting All Results from Subclass Of table

UE - Anim - Gameplay - May 22, 2025

Trying to use the Evaluate Chooser node in the All Results mode with a chooser table that returns the Subclass Of type results in a compilation error ("Array of Actor Object References is not compat ...

Reimporting an asset during PIE overwrites the bAllowCPUAccess value to true

UE - Editor - Content Pipeline - Import and Export - May 22, 2025

When reimporting a static mesh asset before PIE execution, the value of bAllowCPUAccess is false.  If reimporting a static mesh asset while PIE is running, the value of bAllowCPUAccess is true. In a ...

Specular highlight and roughness issue on clearcoat material with second normal at certain view angles

UE - Graphics Features - May 21, 2025

Specular highlights on non-Nanite meshes with a clearcoat material that has the second normal enabled will disappear at certain view angles. This can be worked around by adding a constant node to th ...