UGeometryCollectionComponent::EventDispatcher gets registered for events twice what can result in duplicate collision events being fired

UE - Simulation - Visual - Sep 18, 2024

UGeometryCollectionComponent::EventDispatcher gets registered for events twice, once in UGeometryCollectionComponent::RegisterForEvents() and again in UChaosGameplayEventDispatcher::OnRegister(). Th ...

Cut & Paste in Sequencer breaks with Attach track

UE - Anim - Sequencer - Jan 15, 2025

Cutting two tracks in sequencer, which one is attached to another one, and pasting it break with Attach track. By this operation, Attack track loses its binding object. Copying such tracks and paste ...

'Malformed sequence hierarchy' ensure hit after modifying sub-sequence tracks

UE - Anim - Sequencer - Sep 5, 2025

It's possible for there to be multiple instances of the same sequence in the evaluation states cache if the same sequence is used in multiple sub-sections. Caches are never removed from the evaluat ...

Local class variables do not correctly populate

UE - Gameplay - Blueprint - Dec 2, 2015

Local class type variables do not correctly populate with default value information. Variables of a class type populate with default value information normally. ...

Inside a BP Interface, changing a Function output to an input will cause a compile error in the reference bp

UE - Gameplay - Blueprint - Apr 6, 2015

Inside a BP Interface, changing a Function output to an input will cause a compile error in the reference bp. [Error] "Graph named 'NewFunction_0' already exists in 'bpActor'. Another one cannot be ...

Calling SetupAttachment/AttachToComponent with 'this' as the parent inside a USceneComponent subtype's C++ ctor for nested component subobjects will result in all instances of the nested default subobject trying to attach to the CDO at registration time.

UE - Gameplay - Nov 16, 2016

This occurs because the 'AttachParent' property is a UPROPERTY, and as a result when we create a new instance of a USceneComponent subtype, any USceneComponent subtypes it owns are treated as instan ...

Incorrect restitution behavior for physical material set to 1 whereby momentum is gained during the simulation

UE - Simulation - Physics - Mar 24, 2015

Setting a restitution of 1 for a ground material and a restitution of 1 for a ball that bounces on the ground should keep the ball bouncing at the same height consecutively. Over the course of time ...

Crash filtering for animation sequence with Content Examples animation level open - Assertion failed: MorphTargetWeights.Num() == SkeletalMesh->MorphTargets.Num()

OLD - Anim - May 27, 2016

Editor crashes in Content Examples when the user filters for Animation Sequences while having the Animation level open. I was not able to reproduce this crash in UE4/Main. ...

Construct object fails to assign a value when using the level blueprint - ConstructObject node issue

UE - Gameplay - Blueprint Compiler - Feb 28, 2018

https://udn.unrealengine.com/questions/419239/uk2node-genericcreateobject-compile-issue.html ...

"On List Selection Changed" Retrieves The Wrong Item When "Set Item Selection" is used.

UE - Editor - UI Systems - Jan 8, 2020

When a list view item in UMG is selected using "Set Item Selection" it will get the item of the first entry in the list or the last entry manually selected by the user. The correct item display nam ...