Unreal Engine Issues
Unreal Engine Issues
Crash When Raycasting Against Mesh With Multiple Materials
UE - Simulation - Physics - Feb 26, 2016When using a raycast trace against a blueprint that has a child component with multiple materials will cause the editor to crash after a few times. This will not be an instant crash, but requires th ...
ResolvedView.DirectionalLightColor and DirectionalLightDirection go black when one of several directional lights is removed from the scene
UE - Rendering - Features - Sep 25, 2026With more than one directional light in the scene, ResolvedView.DirectionalLightColor and ResolvedView.DirectionalLightDirection can report the wrong light, or black and a zero vector, while a direc ...
FViewElementPDI::DrawLine calls for SDPG_World are not rendered in PIE or in Game
UE - Rendering - 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 ...
Bug in StringTemplate.cpp related to modulo operator in MaterialTemplate.ush (code fix provided)
UE - Rendering - Architecture - Materials - Jun 25, 2024Shader Template files like MaterialTemplate.ush do not submit previous chunks when encountering a `%` character, unless that `%` character is `%s` or `% {...} `. Because the error is happening ...
[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( ...
Pressing Cancel after ColorPicking a Sequencer's tracked Color will not reverted the color to the previous value
zComponent - Archive - Jun 22, 2025Pressing Cancel after ColorPicking a Sequencer's tracked Color will not reverted the color to the previous value. There's a bug when ColorPicking a color that is being tracked in Sequencer - pressin ...
[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 ...
Sequencer frame range progression is not continuous
zComponent - Archive - Oct 28, 2021The end of the level visibility section places a DeterminismFence. This causes the issue. The fence clips the frame range and produces a discontinuous frame ranges, e.g. 23201~24000, then 24001~24 ...
Unloading level during PIE leads to editor crash
Tools - Dec 6, 2017Unloading level during PIE seems to lead to an editor crash. Most easily reproducible by enabling malloc stomp. ...