Unreal Engine Issues
Unreal Engine Issues
check(bRenderStateCreated) fires in SendRenderDynamicData_Concurrent called from FRegisterComponentContext::Process
UE - Rendering - RHI - May 18, 2026FRegisterComponentContext::Process() in ActorComponent.cpp iterates over SendRenderDynamicDataPrimitives and calls SendRenderDynamicData_Concurrent() on each. The existing guard checks ::IsValid(Pri ...
Wrong WPO motion vectors due to Periodic World Space node
UE - Rendering - Features - May 13, 2026We've noticed smearing in grass due to wrong motion vectors. This appears to be caused by lack of previous frame support in the periodic world space node. This is how we fixed it: In MaterialTempl ...
Chaos FieldSystem examples in the engine content add field nodes every Tick, which creates too many components
UE - Runtime - Character - May 5, 2026Can we add the field on construction instead of on Tick to avoid the performance overhead caused by creating too many components? ...
Curve Atlas Row Parameter uses derivative ops when Texture Sample connected to curveTime input
UE - Rendering - Architecture - Materials - May 1, 2026When a Curve Atlas Row Parameter node is used with a Texture Sampler connected to the curve time input, the sample type uses derivative ops. This has negative performance implications for Nanite co ...
Blueprints: ComponentClass override causes crash on loading maps with instances saved with base class
UE - Framework - Blueprint - May 1, 2026Context In actor blueprints, you can change an inherited component’s class in the editor by selecting it in a child blueprint and changing its Component Class in the Details panel. Problem When o ...
CharacterMovementComponent boosted upward when falling into acute-angle sloped corner
UE - Runtime - Character - Apr 14, 2026In UCharacterMovementComponent::TwoWallAdjust, characters can gain unintended upward velocity (slope boosting) when hitting corners with an acute angle (<=90 degrees) while in the Falling movement m ...
Raytraced Hair Lighting using Light Functions atlas and positions the Light function material doesn't render correctly
UE - Rendering - Features - Apr 9, 2026Light functions don’t render on grooms when using ray traced shadows and positions in the light function material. The setup:A light (point/rect/spot) pointing to a groom hair system. The light's ...
HandleKismetEvent (console cmd 'ke'): GT-ALT deadlock when user function flushes async loading
UE - Core - Asset Loader - Apr 8, 2026Context In builds with the in-game console enabled, users can use the ‘ke’ command to execute UFUNCTIONS on any object:ke * MyFunc // run MyFunc() on ANY UObject with a ufunction with that name ke ...
Control Rig + Animation in Sequencer Can Lead to Unexpected Slider Reset
zComponent - Archive - Mar 30, 2026When a character has both a Control Rig track and an Animation track, interacting with any slider in Sequencer can be interrupted. ...
Hair Shadows Not Affecting SSS Back Scattering (Subsurface Profile)
UE - Rendering - Features - Mar 30, 2026Groom strands do not appear to correctly block transmitted light for Subsurface Scattering Profile Materials. In some cases, not only will they not block the light, but can instead lead to more ligh ...