FStaticMeshCompiler::FinishCompilation stalls when compiling multiple meshes.

UE - CoreTech - Oct 7, 2024

Calling "FStaticMeshCompiler::FinishCompilation" on multiple assets simultaneously can cause a hang. Also tested on //UE5/Release-5.5, CL: 36784631 ...

Sequencer: Skeletal Animation with montages can cause blending issues when re-playing the same sequence on the same character

UE - Anim - Sequencer - Oct 1, 2024

The code in MovieSceneSkeletalAnimationSystem.cpp storages montage data on a per skeletal mesh component, per section basis. This (and a few other bits of logic) cause issues for external UDN user w ...

Invalid access location compressing a BC6h texture in the editor

RAD - Oct 29, 2024

Large texture crashes during Oodle compression with "-stompmalloc". It appears to be an internal Oodle error. Also tested on //UE5/Release-5.5/, CL: 37463908 ...

Depth of Field blur is inconsistent with r.ScreenPercentage == 100 (Dynamic resolution)

UE - Graphics Features - Oct 29, 2024

Depth of Field, with "r.DOF.Recombine.Quality = 0" will adjust the size of the depth in focus based on screen percentage. This might be related to over-fitting from the tile classification, because ...

ISM + WPO = broken motion vectors?

UE - Graphics Features - Nov 5, 2024

Instanced Static Meshes will have incorrect velocity if a Material uses World Position Offset. Fixed WPO in a material causes significant velocity on the ISM. This was also replicated in //UE5/Rele ...

Translucent light grid injection behavior

UE - Graphics Features - Nov 15, 2024

Light injection into the Translucent Light Grid voxels does not use the correct location for clipping or attenuation. Both of these points are outside the voxel that is being updated. Light attenua ...

Global SkyAtmosphere and Clouds Issues (Cloud Shadows)

UE - Graphics Features - Dec 3, 2024

Sampling Cloud Shadows when rendering the Sky Atmosphere can incorrectly assume that the view is located at the planet's North Pole. This causes distortion in the shadows when using a sphere-shaped ...

Global SkyAtmosphere and Clouds Issues (Ambient Light)

UE - Graphics Features - Dec 3, 2024

Ambient Light on Volumetric Clouds from Sky Atmosphere always is calculated as if the clouds are at the north pole of the planet. Using a sphere-shaped Sky Atmosphere and Volumetric Clouds causes t ...

r.Lumen.Reflections.DownsampleFactor split screen artifact

UE - Graphics Features - Lumen - Dec 6, 2024

In Split-Screen, with "r.Lumen.Reflections.DownsampleFactor" set to 2, it is possible to have vertical colored artifacts on View 1 (the second view). The Licensee reported the artifact occurred on ...

Substrate SSR reflections are black

UE - Graphics Features - Substrate - Dec 17, 2024

Substrate Materials do not use Screen-Space reflections. Instead, they do not have any reflections (indirect specular) on the surface. ...