Unreal Engine Issues

Assert crash when playing Groom Cache with Card Mesh LOD

Playing a Guides Groom Cache while Card Mesh LOD (Guide-Based) is active causes an assert in RunHairStrandsInterpolation_Cards when the renderer switches to Card LOD. Assert location:Plugins/Runtim ...

Niagara Mesh Renderer registers NumParticles x NumMeshVariants TLAS instances

When using the Niagara Mesh Renderer with multiple mesh variants selected via MeshIndex, the number of TLAS instances allocated is NumParticles × NumMeshVariants and enabling the Path Tracer can ca ...

PrepareTextureResources is being called repeatedly (on commandlets and potentially other cases)

Implement a commandlet that renders (with `-AllowCommandletRendering`) and frequently calls `CommandletHelpers::TickEngine()`.Have the commandlet load a map containing a world-partitioned landscape. T ...

Blocky artifacts in right eye when reflection captures are used

StreamingGeneration: Actor desc mutator phase now writes ActorDescView directly, breaking the cluster-invariant check in ValidateContainerInstanceDescriptors

This report is from an EPS case: We hit a regression upgrading our project from 5.7 to 5.8. Map Check (and any other path that ends up calling UWorldPartition::CheckForErrors) assert inside FWorld ...

Crash with SceneCapture DepthPrepassOptimization enabled

FNiagaraRendererMeshes::GetDynamicRayTracingInstances(...) corrupting GPUScene when rendering multiple views

When rendering a game in splitscreen using Lumen HWRT, Nanite and a large number of Niagara Mesh Particles 1mil+, various meshes and actors will stop rendering. Setting r.RayTracing.Geometry.Niagar ...

VSM r.Shadow.Virtual.UseReceiverMaskDirectional Breaks Cache Behavior Overrides

Since 5.7 this CVAR has been turned on by default and it ibreaks / prevents shadow cache behaviour to be set as we used to in 5.6 on meshes when r.Shadow.Virtual.UseReceiverMaskDirectional 1 Most o ...

ApplyLocalExposure uses Output_ExtentInverse instead of Output_ViewportSizeInverse for bilateral grid UV

The ApplyLocalExposureCS shader in PostProcessLocalExposure.usf computes UV coordinates for the LumBilateralGrid 3D texture using Output_ExtentInverse (1/RenderTargetSize) instead of Output_Viewport ...

[Enhanced Input] Chord trigger fails when its referenced action lives in a lower-priority IMC

Summary A UInputTriggerChordAction does not fire when the action it references (the "chording action") is mapped in a different Input Mapping Context with a lower priority than the IMC containing the ...