Unreal Engine Issues
Unreal Engine Issues
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 ...
Long load time for files with large numbers of trees in 2025.2
TM - Core - Oct 6, 2025Reported in SF [Link Removed] User reports that multiple files with large amounts of trees take substantially longer to load in TM 2025.2 compared to 2025.1.1. Confirmed with one of the user's fil ...
Import then cancel while file is read leads to potential crash
TM - Interoperability - Oct 6, 20251/ Import a file with mootools such as an fbx 2/ while the file is still read, cancel the import Result : may crash few times after (when theoretically the file has finished being read) - not repr ...
Incorrect Lumen Scene direct lighting when objects behind masked landscape
UE - Graphics Features - Lumen - Oct 5, 2025When objects are placed behind or beneath a masked landscape and r.Lumen.HardwareRayTracing.SurfaceCacheAlphaMasking is enabled, the direct light evaluation is incorrect. There are two workarounds, ...
TMatrix<T>::InverseFast() ensure when running URootMotionModifier_SkewWarp::WarpTranslation().
UE - Anim - Gameplay - Oct 3, 2025URootMotionModifier_SkewWarp::WarpTranslation() uses InverseFast() within a block of code that is only executed if DeltaTranslation is not nearly zero. The ToRootSyncSpace transform the code builds, ...
TMaps do not function as expected in the details panel when then TMap variable is in a blueprint component
UE - Framework - Blueprint - Oct 3, 2025The default element can be added multiple times and changing the value from the drop down. ...