Duplicating a blueprint that implements an interface and then removing that interface will cause compile errors that don't occur if the interface was removed from the original BP

UE - Gameplay - Blueprint Editor - Aug 1, 2020

See steps to reproduce. Looks like the fixup when saying Yes to "Would you like to transfer the interface functions to be part of your blueprint" doesn't work correctly on the duplicated BP. Inter ...

When show propertymatrix and delete target actor, the editor crash

Tools - Jul 11, 2017

It looks like it is null reference in propertymatrix. It always occurs when I execute the reproduction procedure. ...

Increment and decrement nodes return the incorrect value

UE - Gameplay - Blueprint - Jun 23, 2015

Increment and decrement nodes return the incorrect value User Description: Getting the result of the Increment Macro seems to be incrementing the variable twice. Very confusing. Is this normal? ...

Engine Crashes When Trying to Add an Entry to a TMap in a Nested Struct That is an Element of an Array

Tools - Oct 3, 2019

When trying to add an entry to a TMap in a nested struct that is an element of an array the engine crashes. This doesn't happen if it is not an array of the nested struct. Attached are .h and .cpp ...

Crash editor when raytracing is enabled and enter kanji characters into TextRenderActor

UE - Graphics Features - Ray Tracing - Apr 25, 2024

The editor crashes when entering Kanji characters into TextRenderActor with raytrace enabled. This does not happen with English text.  ...

bIgnoreAllPressedKeysUntilRelease behaves differently for triggers in EnhancedInputAction and triggers in InputMappingContext

UE - Gameplay - Input - Aug 10, 2023

For actions that are triggered on the Input mapping context, simply adding or removing an InputMappingContext with no related key override with the bIgnoreAllPressedKeysUntilRelease option will caus ...

Some Niagara FX does not show up in MovieSceneCapture when AgeUpdateMode is DesiredAgeNoSeek

UE - Niagara - Cinematics - Sep 17, 2024

CL23957356 changes how to calculate FrameOffset in FNiagaraSystemUpdateDesiredAgeExecutionToken::Execute(). After this change, DesiredAge + FrameOffset could be 0.0 for some a couple of initial fram ...

FKConvex::ElemCalcAABB ignoring current transform.

UE - Simulation - Physics - Apr 15, 2016

FKConvexElem::CalcAABB was ignoring the elements currently defined transform, and only scaling. This means that any actor that has a transform (not just Merge Actors) could potentially have very dis ...

Crash When Raycasting Against Mesh With Multiple Materials

UE - Simulation - Physics - Feb 26, 2016

When 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 ...

On Hit Events are inconsistent/inaccurate when using Substepping most notably at lower frames per a second

UE - Simulation - Physics - Dec 9, 2021

This is a regression Tested in: //UE4/Release-4.27 CL18319896 Binary //UE5/Release-5.0-EarlyAccess CL16682836 Binary Under the same conditions in UE4 the On Hit events fire accurately and as expect ...