GeometryCollectionComponent visibility flag is forced to true in BeginPlay

UE - Simulation - Physics - Destruction - Jan 26, 2023

The visibility flag is reset to true in UGeometryCollectionComponent::UnregisterFromISMPool. This function is called from BeginPlay. Only when ISMPoolActor is not being used, the following worka ...

Components attached via AttachToComponent do not animate correctly when recorded by sequencer

UE - Anim - Sequencer - May 25, 2016

When an actor is attached by the root to a bone of a skeletal mesh through the use of the "AttachToComponent" function in code, it will not follow animations when being recorded by the Sequencer Rec ...

Custom Component Being Added to Wrong Target Blueprint

UE - Gameplay - Components - Nov 2, 2015

When attempting to add a custom component to a blueprint at runtime using the Add Component function, if you give the component an exposed variable, it will ignore whatever target you specify and ad ...

Unable to bind events to OnPerceptionUpdated in Blueprints

UE - Gameplay - Blueprint - Dec 18, 2017

Attempting to bind an event to OnPerceptionUpdated results in an error in Blueprints. It seems that this is caused by the TArray in the function signature not being a constant reference. Current co ...

UMovieSceneTrackInstance::GetWorld() does NOT work properly in Editor

UE - Anim - Sequencer - Mar 28, 2023

UMovieSceneTrackInstance::GetWorld() returns nullptr on Editor, so user can't use any function using WorldContext and Subsystem. The following code change may fix this issue UWorld* UMovieSceneTra ...

Crossfade sharing doesn't allow more than one shared transition

OLD - Anim - Apr 29, 2016

Looking at the propagate function:void UAnimStateTransitionNode::PropagateCrossfadeSettings() { UEdGraph* CurrentGraph = GetGraph(); for (int32 idx = 0; idx < CurrentGraph->Nodes.Num(); idx++) ...

Crash Occurs When Using Invalid HideCategories

UE - Gameplay - Blueprint - Aug 8, 2016

The licensee is experiencing a crash when using UCLASS(HideCategories = (Activation, LOD, Collision, Rendering, TextureStreaming, Lighting, Mobile, Transform, Physics, Tags)) This crash occurs afte ...

[Groom] Very thin hair has incorrect raytraced shadow on edges

UE - Graphics Features - Lumen - Jun 8, 2020

This only happens when 1) Hair Width is very small. e.g. 0.01 in the example 2) Light has raytraced shadow and Samples Per Pixel has a value > 1. e.g. 8 in the example The problem seems to be rel ...

Anim Notify States are ended when CustomTimeDilation is set to zero

UE - Anim - Runtime - Oct 12, 2022

UDN link: https://udn.unrealengine.com/s/question/0D54z00008BEDfJCAX/set-actor-time-dilation-to-0-during-a-animation-notify-state-cancel-it?fromCase=1 Notify gathering functions (e.g. UAnimSequence ...

Shader Model 5 and Tessellation causes unintended effects on Linux

UE - Platform - Linux - Jul 6, 2016

Using Shader Model 5 and tessellation on Linux gives strange results that are not present when used on Windows ex: 1) When using Shader Model 5 on Linux, turning on Translucent blend mode and Tesse ...