Unreal Engine Issues
Unreal Engine Issues
Crash when a Deferred Decal (Translucent) base material has a Nanite Override (Masked Surface) Material and the mesh has Nanite + Ray Tracing enabled.
UE - Graphics Features - Ray Tracing - Aug 14, 2025A crash occurs when Nanite override material instance is used in a project with Ray tracing enabled where: 1 The Material assigned to the static mesh uses Deferred Decal / Translucent and the Nani ...
[CrashReport][Crash] Engine!FSceneViewport::UpdateViewportRHI() [SceneViewport.cpp]
UE - Rendering - Architecture - RHI - May 29, 2026#200 crash out of 2101 in UE 5.8 on Windows#34 crash for UE - Rendering - Architecture in UE 5.8 on Windows#20 crash for UE - Rendering - Architecture - RHI in UE 5.8 on WindowsAssertion failed: IsI ...
Instanced static meshes fire an erroneous performance assert about loose parameters.
UE - Graphics Features - Sep 4, 2019"This ensure is intended to catch regressions where rendering programmers add a loose parameter to LocalVertexFactory, breaking dynamic instancing on regular static meshes. InstancedStaticMeshes c ...
GenerateProxyMesh causes incorrect transform in ISM using Scale
UE - World Creation - Worldbuilding Tools - HLOD - Aug 20, 2019MeshVertex has been converted by component transform before being converted by instance transform. It is ( Vertex * ComponentTransform ) * InstanceTransform. I thought it has to be converted by (Ve ...
FCDODiffControl doesn't properly account for lists of differing size.
UE - Gameplay - Blueprint - Sep 21, 2016FCDODiffControl doesn't properly account for lists of differing size. The issues are marked in the following code:int IterOld = 0; int IterNew = 0; while (IterOld != OldProperties.Num() || IterNew ...
TickComponent and PostPhysicsTick in SkeletalMeshComponent can cause simultaneous read/write access
UE - Runtime - Animation - Jan 18, 2023When a SkeletalMeshComponent is restarted by calling in order of SetSimulatePhysics and SetComponentTickEnabled, the TickComponent and EndPhysicsTick are executed simultaneously. As a result, the ...
Sequencer autosorts alphabetically on undo
UE - Anim - Sequencer - Sep 8, 2023[Link Removed] Jan Kaluza 2023-09-08 15:37:18 UTC I just ran into a very frustrating bug: I have around 60 actors in a sequence, and I reordered them to be in the order that I wanted to animate them ...
Packaging for HTML5 seems to have grown in package size
UE - Platform - Mobile - Aug 30, 2016The size of packages for HTML5 has greatly increased since 4.10.4 to 4.11.2 and has since increased. Example: First person template, no starter content - size of whole HTML5 folder once packaged: 7 ...
SAnalogSlider moves slowly when step size is large
UE - Editor - UI Systems - Slate - Mar 6, 2024SAnalogSlider calculates FastestStepTime by multiplying the step size value by a constant, resulting in high numbers for larger step sizes. This gets lerped from 1 and used as the repeat time, resul ...
LOD glitch when using Control Rig with Import Skeleton node
UE - Anim - Rigging - Control Rig - Aug 26, 2025In Unreal Engine 5.6 and Main, a glitch occurs when switching between LODs in a character setup that uses a Control Rig to dynamically load the skeleton hierarchy through the Import Skeleton node in ...