Inherited Blueprint component template data is not being validated on save.

UE - Gameplay - Blueprint - Sep 8, 2022

UBlueprint::IsDataValid() does not currently check component templates inherited from a parent Blueprint class asset's SimpleConstructionScript; only the current class hierarchy is considered. Given ...

"FVector contains NaN" on packaged builds for Debug configuration

UE - Graphics Features - Lumen - May 6, 2022

Customer Provided Description:This was experienced in UE 5.01 - custom installed engine (No changes to UE code, simply added the Debug build configuration, see the following command): "c:%ue_dire ...

[Sound Submix] - Dry Level of a Submix is calculated differently whether or not there is an effect in the chain

UE - Audio - Submixes - Jan 21, 2021

There is a discrepancy is how the output volume of a submix is calculated when the effect chain is and is not populated. When there is no effect on the submix, the Dry Level adds additional gain to ...

Invalid GUIDs on new material instance parameters cause overrides to break on base param rename

UE - Rendering Architecture - Materials - Sep 3, 2025

When a parameter value is assigned on a newly created material instance (constant or dynamic) using Set***ParameterValueInternal, the parameter’s ExpressionGUID is left invalid (0,0,0,0). Parameter ...

Adding a Reroute node to a function's array output will cause the Function node to be missing the output

UE - Gameplay - Blueprint - Mar 26, 2015

Adding a Reroute node to a function's array output will cause the Function node to be missing the output. This seems to be only effecting Arrays. Standard variables work fine. ...

Set Ignore Look Input stacks the resulting value each time it is called

UE - Gameplay - Jan 5, 2015

Set Ignore Look Input stacks the resulting value each time it is called. If Set Ignore Look Input is called more than once with the same value, it will take as many calls with the opposite value to ...

Setting a parent and child static mesh scale to negative effects the rotation on child when Snapped To Floor

UE - Gameplay - Jul 21, 2016

Setting a parent and child static mesh scale to negative effects the rotation on child when Snapped To Floor Looks to be directly related to this JIRA: https://jira.ol.epicgames.net/browse/UE-3152 ...

Global SkyAtmosphere and Clouds Issues (Cloud Shadows)

UE - Graphics Features - Dec 3, 2024

Sampling Cloud Shadows when rendering the Sky Atmosphere can incorrectly assume that the view is located at the planet's North Pole. This causes distortion in the shadows when using a sphere-shaped ...

Native default subobjects nulled in child Blueprints on compile

UE - Gameplay - Blueprint Compiler - Oct 25, 2021

From reporting UDN: "We had a weird issue with new components added in C++ not being instanced properly on non-direct Blueprint children. It seems to happen if loading of the parent BP is deferred ...

r.VolumetricRenderTarget.PreferAsyncCompute producing different visuals

UE - Graphics Features - Aug 2, 2024

When the cvar "r.VolumetricRenderTarget.PreferAsyncCompute" is enabled, it will cause Volumetric Clouds to ignore the influence of Volumetric Fog. In high-fog environments, this can cause the clouds ...