Unreal Engine Issues
Unreal Engine Issues
[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 ...
Assert crash when playing Groom Cache with Card Mesh LOD
UE - Rendering - Graphics Features - May 29, 2026Playing 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
UE - Rendering - Graphics Features - Ray Tracing - May 28, 2026When 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)
UE - Graphics Tools - Terrain - Landscape - May 28, 2026Implement a commandlet that renders (with `-AllowCommandletRendering`) and frequently calls `CommandletHelpers::TickEngine()`.Have the commandlet load a map containing a world-partitioned landscape. T ...
check(bRenderStateCreated) fires in SendRenderDynamicData_Concurrent called from FRegisterComponentContext::Process
UE - Rendering - Architecture - RHI - May 18, 2026FRegisterComponentContext::Process() in ActorComponent.cpp iterates over SendRenderDynamicDataPrimitives and calls SendRenderDynamicData_Concurrent() on each. The existing guard checks ::IsValid(Pri ...
ServerUpdateLevelVisibility called multiple times from UWorld::AddToWorld/RemoveFromWorld due to child connections
UE - World Creation - Worldbuilding Tools - World Partition - Apr 16, 2026A recent change to ULevelStreaming::ServerUpdateLevelVisibility ensures that this only calls APlayerController::ServerUpdateLevelVisibility once for any non-child connections ( ...
Chaos Fields: LS_MasterField continuously creates components every frame and never cleans them up
UE - Simulation - Visual - Mar 25, 2026While active and ticking, the built-in FS_MasterField actor instance continuously creates several new components every frame, which are never cleaned up until the actor is destroyed. This can happen ...
Crash in FWebRemoteControlModule::HandleBatchRequest() when not enforcing passphrase on requests
UE - Virtual Production - IO - RemoteControl - Mar 20, 2026When a client sends a request with no passphrase to Unreal Remote Control's "/remote/batch" endpoint, and the plugin is configured to not perform passphrase verification, the Editor will crash as so ...
JsonObjectToUStruct removes _ClassName from input FJsonObject, breaking repeated deserialization
UE - Foundation - Mar 18, 2026FJsonObjectConverter::JsonObjectToUStruct removes _ClassName from nested JSON objects during deserialization. Removing Obj->RemoveField(ObjectClassNameKey) from ConvertScalarJsonValueToFPropertyWit ...
Cursor radius set via FSlateApplication::SetCursorRadius is ignored during FHittestGrid hit testing
UE - Editor - UI Systems - Slate - Mar 16, 2026The cursor radius configured through FSlateApplication::SetCursorRadius() is not respected during Slate hit testing. The radius value is correctly stored in FSlateApplication and passed into FHittes ...