[Feature Request] Improve the comment on the Finterp family of functions to better explain the parameters and maybe edge cases like what happens when speed is 0)

UE - Gameplay - Apr 24, 2017

Some users are finding the result of an interp speed of 0 for the FinterpTo node to be unexpected. The reasoning expressed is that if the speed is equal to 0 that there should be no change. This would ...

Sky Atmosphere Material Nodes not Correctly Represented in the Surface Cache for Nanite Enabled Static Meshes

UE - Graphics Features - Apr 1, 2025

When nanite is enabled on a static mesh, lighting contributions from Sky Atmosphere material nodes are not incident on the static mesh and no longer present in the overall lighting of the scene. Th ...

UClass::HasProperty() returns true for properties in a child class even though the comment for the function indicates it checks for the property in the current class and parents of the current class

UE - Foundation - Core - Dec 21, 2018

The comment describing UClass::HasProperty() indicates that it checks to see if a specified property exists in a class, or a parent of that class. However, when a property that exists in a child of ...

Old property values can be applied when updating an unmapped reference in custom NetSerialize struct

UE - Networking - Apr 13, 2023

This seems to be caused by the following:The struct, which has an actor reference property as well as some other properties, implements its own NetSerialize function.When the actor reference propert ...

FIntVector has some code that refers to it being two dimensonal

UE - Gameplay - Mar 10, 2016

There is code in the FIntVector class (IntVector.h) that seems to be copied from the FIntRect class which is a problem since FIntRect is two dimensonal while FIntVector is three dimensional. The one ...

UEditorValidatorBase::ValidateLoadedAsset() is not using the K2_ValidateLoadedAsset() output, effectively ignoring the Blueprint validation

UE - Editor - Content Pipeline - May 1, 2025

UEditorValidatorBase::ValidateLoadedAsset() is not using the K2_ValidateLoadedAsset() output, effectively ignoring the Blueprint validation. The K2Result is not used later in the function, and this ...

Crash in UDataTable::RemoveRow(FName RowName)

UE - CoreTech - Jun 13, 2025

This is a regression, the crash seem to have been introduced by CL 40129784 on ue5-main and persists in latest. Function UDataTable::RemoveRow(FName RowName) uses macro DATATABLE_CHANGE_SCOPE_SINGL ...

VSM SMRT SamplesPerRay CVars behave differently if groom assets are present leading to a potential full-scene shadow

UE - Graphics Features - May 28, 2025

When a groom is present, setting any SamplesPerRay SMRT CVar to zero results in an unexpected complete shadow projected from the light. ProjectLight() in VirtualShadowMapProjection.usf has addition ...

[CrashReport] Failed assert during BP compilation (trying to call a default delegate) (UE4Editor_KismetCompiler!FScriptBuilderBase::EmitFunctionCall() [kismetcompilervmbackend.cpp:1216])

UE - Gameplay - Oct 27, 2017

This is a trending crash coming out of the 4.18 release. User DescriptionsI tried to call an Event Dispatcher (which is assigned in the Level Blueprint) in the Construction Script of the Blueprint ...

When using StringToBytes() it returns an incorrect value

UE - Foundation - Core - Jan 4, 2018

When using the StringToBytes() function it returns one less byte due to the -1 at the end of the return. The function takes a string and converts it to bytes but it always returns one less byte than ...