Unreal Engine Issues
Unreal Engine Issues
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 ...
Regression - Nested scene component subobjects are no longer being registered when the owning scene component is added to an existing Actor instance as an instanced component.
UE - Gameplay - Components - Nov 16, 2016This is a regression that was introduced with changes made to address issues with native vs. non-native component registration at Blueprint construction time ([Link Removed]). Prior to those change ...
Editor crash when a spline component is added to a blueprint and compiled
Tools - Sep 7, 2016Most recent user affected CL: 3106830 (4.13.0) Error message: Access violation - code c0000005 (first/second chance not available) Source Context: SelectedKeys = SplineVisualizer->GetSelectedKey ...
[CrashReport] UE4Editor_D3D11RHI!TerminateOnDeviceRemoved() [d3d11util.cpp:176]
UE - Graphics Features - Nov 18, 2016Error message: Fatal error: [Link Removed] [Line: 176] Unreal Engine is exiting due to D3D device being lost. (Error: 0x887A0006 - 'HUNG') Source Context: 161 162 const TCHAR* Rea ...
Editor Utility Widgets: Asset creating nodes' output pins in uber graphs cause asset deletion warning
UE - Framework - Blueprint Runtime - Oct 8, 2024Editor Utility Widgets (EUW) can be used to script editor behavior. One use case is the automation of asset creation. A licensee has reported that when an EUW is used to create an asset, for as lon ...
FKeyHandle internal static atomic counter can overflow on long running games depending on usage pattern
UE - Anim - Sep 24, 2025Structure FKeyHandle stores an internal index, which is initialized from a static atomic counter in the default constructor: +----- FKeyHandle::FKeyHandle() { | static std::atomic<uint32> LastKey ...
Given specific, non consistent, network connections, replication of some data can result in incorrect values
UE - Networking - Nov 2, 2016I appears to be possible to replicate a value and when the value gets to the client(s), it doesn't match what was sent from the server. In the project, ReplicatedActor is created by the Authority. ...
Compilation errors with UE_NET_ENABLE_REPLICATIONREADER_LOG enabled
UE - Networking - Iris - Jul 15, 2024Enabling UE_NET_ENABLE_REPLICATIONREADER_LOG results in the following errors: {{4>[1/5] Compile [x64] ReplicationReader.cpp 4>D:\P4V\UE5-Main\Engine\Source\Runtime\Experimental\Iris\Core\Private\Ir ...
Sequencer based Camera Shake throws an assertion when spammed
UE - Anim - Sequencer - Apr 7, 2022Activating a Sequencer based Camera Shake repetitively results in an assertion being thrown. Assertion failed: DestAllocationIndex != SourceAllocationIndex [File:D:\build\++UE5\Sync\Engine\Source\R ...
Custom UVs don't store information properly in layered materials.
UE - Rendering - Architecture - Materials - May 9, 2022[Link Removed] I have this set up so that FX artists can stack UV manipulations, so I don't want to just have all the UV manipulation in the layer with the base color, even though that does give me ...