Unreal Engine Issues
Unreal Engine Issues
Double to float conversions of time in renderer causes precision issues
UE - Rendering - Architecture - Materials - Apr 8, 2026In game sessions when the value for world time becomes large enough we start running into floating point precision issues. These issues can easily be seen in materials which do periodic animation b ...
Crash when trimming animation and then undoing action
UE - Anim - Runtime - May 30, 2023Repro rate: 3/3 times This is a regression as the issue does not occur in 5.1.1 ...
PCG crash when using Attribute Remove Duplicates on partitioned data if one of those sets of data is empty
UE - World Creation - Procedural Tools - PCG Graph - Jul 3, 2025Context: In PCG, the Attribute Remove Duplicates node can be used to remove duplicate attributes from an array. Problem: The licensee has observed that using the Attribute Remove Duplicates node ...
Changing MaterialQualityLevel causes a crash due to a ShaderMap mismatch in UniformExpressionCache
UE - Rendering - Architecture - Materials - Nov 26, 2025A crash may occur when changing the MaterialQualitylevel via Scalability due to a race condition. The issue occurs because in ScalabilityCVarsSinkCallback(), when it creates the FGlobalComponentRec ...
Nanite Displacement Bounds Mismatch Causes Floating Terrain Artifacts on Landscape
UE - Rendering - Graphics Features - Nanite - Mar 19, 2026Summary When Nanite Tessellation (Nanite Displacement) is enabled on a Landscape in UE 5.7.3, scaling the Displacement value via Multiply nodes in the material graph causes floating terrain ghost a ...
FViewElementPDI::DrawLine calls for SDPG_World are not rendered in PIE or in Game
UE - Rendering - Architecture - RHI - Jan 7, 2026When View.Family->EngineShowFlags.CompositeEditorPrimitives is false in the function RenderEditorPrimitivesForDPG. This code picks which version of the batched lines to renderconst FBatchedElements ...
[CrashReport] UE4Editor_MaterialEditor!FMaterialEditor::GetToolkitName() materialeditor.cpp:820
UE - Rendering - Architecture - Materials - Nov 21, 2017This is a new crash coming out of the 4.18.1 hotfix. There is no record of it previously occurring, so it is possible it may be a regression. Users have not provided any descriptions of their actio ...
[CrashReport] UE4Editor_UnrealEd!PackageTools::ReloadPackages() [packagetools.cpp:576]
Tools - Jun 29, 2017This is a common crash affecting users on 4.16. Users have not provided any descriptions, so additional information is currently unavailable. Source Context 561 ::SortPackagesForReload( ...
[CrashReport] UE4Editor-TargetDeviceServices.dylib!TRawMessageHandler<FTargetDeviceServicePong, FTargetDeviceProxyManager>::HandleMessage(TSharedRef<IMessageContext,()
UE - Platform - Apple - Oct 5, 2017This is a slightly common Mac crash that has occurred since 4.17.1. Users have not provided any descriptions of their actions when the crash occurred. Callstack from Log[2017.09.28-15.29.17:473][3 ...
Crash when switching from Lumen visualization to raytracing visualization
UE - Rendering - Graphics Features - Mar 27, 2026When switching from Lumen visualization to raytracing visualization via the console, the editor can crash to desktop. The crash appears to happen deep within the driver libraries, and does not trig ...