Unreal Engine Issues
Unreal Engine Issues
Lightmass CalculatePointShadowing regression in UE5.6
UE - Graphics Features - Oct 14, 2025There is a regression or change in the Build Lighting process when using Lightmass in Unreal Engine 5.6:When building lighting with Lightmass calling the CalculatePointShadowing function, the result ...
When exporting from a level sequence, the LOD for the bones is based on the camera distance, instead of using LOD0
UE - Anim - Sequencer - Oct 9, 2025When exporting a level sequence to an animation sequence, the bones used will be based on the LOD for the current camera location, instead of exporting LOD0. This is very noticable if you pull the ...
Ensure triggered in FBoundsCacheElement::GetValue when adding ISM instances in Construction Script
UE - AI - Oct 8, 2025An ensure is triggered in FBoundsCacheElement::GetValue when adding instances to an InstancedStaticMeshComponent inside a Blueprint’s Construction Script. This occurs when the ISM component is navig ...
HZB Occlusion causes large stalls on the render thread
UE - Rendering Architecture - RHI - Oct 7, 2025HZB Occlusion causes large stalls (greater than 5ms seen) on the render thread due to an RHI flush. This is caused by the following code in FDynamicRHI::RHIMapStagingSurface_RenderThread which force ...
Vertex color does not work on Skeletal Mesh with Nanite enabled
UE - Graphics Features - Nanite - Oct 7, 2025Nanite enabled skeletal meshes don't work with materials containing a vertex color node. The vertex color material does work for non-Nanite skeletal meshes and Nanite-enabled static meshes. ...
Converting a mesh to Nanite merges mesh sections with the same material index, but with different material overrides
UE - Anim - Mutable - Oct 6, 2025When a mesh with multiple sections which point to the same MaterialIndex but have different settings enabled (e.g. bCastShadow is enabled on only one section) is converted to Nanite, the material sl ...
Recompiling an ABP that another ABP has a Property Access dependency on without recompiling/linking the other causes a crash
UE - Anim - Runtime - Anim Blueprints - Oct 2, 2025The crash comes from the pointers in FAnimSubsystem_PropertyAccess::Library::Indirections in the layer ABP from pointing to old/invalid functions and properties from the trash ABP_Manny, as they hav ...
Update LookupProxy chooser evaluation to work with soft object references.
UE - Anim - Gameplay - Oct 1, 2025Soft object references in proxy tables, when evaluated return a nullptr, instead of the soft object reference to load. ...
BoxOverlapActors fails to catch an Overlaped actor with a particular scale, from a particular position
UE - Simulation - Core - Sep 30, 2025BoxOverlapActors fails to overlap a scaled Floor actor with a particular scale, from a particular position and extent. The setup is really specific and described in Steps to Reproduce. The required ...