GAS: Duration GameplayEffects applying same GameplayCue tag will on authority end all on-going GameplayCueNotifies when first cue expires

UE - Gameplay - Gameplay Ability System - Aug 16, 2024

When multiple duration GameplayEffects apply a GameplayCue with the same tag, the network authority game instance (standalone & servers) will remove all GameplayCues with that tag from the AbilitySy ...

PDI-DrawPoint - Zoomfactor being calculated incorrectly

UE - Rendering - Graphics Features - Feb 20, 2017

A licensee has reported that the ZoomFactor variable inside of the DrawPoint function is being calculated incorrectly. It currently is calculated using the lesser of the projection matrix's horizont ...

Lumen Reflections in Stereo are broken after Nvidia GPU Driver Update

UE - Platform - XR - Jul 29, 2024

After updating the NVidia graphics driver to v.552.74+, reflective/mirror materials appear broken and render with black and white lines in VR mode if they are in a level with a Post Process Volume w ...

Long thin spinning objects take too long to stop spinning

UE - Runtime - Simulation - Jun 5, 2023

See the SpinningObjectStability test map in the Physics Sandbox. [Link Removed] It's not clear if this is a bug or a side effect of some of our solver shortcuts (e.g., omission of the precession te ...

FBX animations generated under fractional framerates fail to import

UE - Runtime - Animation - Aug 24, 2022

We now have the following error that is generated in FFbxImporter::ValidateAnimStackif (!FMath::IsNearlyZero(SubFrame, KINDA_SMALL_NUMBER) && !FMath::IsNearlyEqual(SubFrame, 1.0f, KINDA_SMALL_NUMBER ...

Null FPhysicsActorHandle dereference in FBodyInstance::InitDynamicProperties_AssumesLocked when CreateShapes_AssumesLocked fails during async body init

UE - Runtime - Simulation - Aug 2, 2026

Summary When CreateShapes_AssumesLocked fails during async body creation, the failed FBodyInstance is left in Bodies[] with a released actor handle. InitDynamicProperties_AssumesLocked is then called ...

Disabling bLerpUVs in Nanite Settings of Static Mesh causes texture warping in clusters

UE - Rendering - Graphics Features - Nanite - Jan 21, 2025

The licensee has identified a potential fix by changing if( Settings.bLerpUVs ) to if( Settings.bLerpUVs || UVIndex == 0 ) On line 389 of NaniteBuilder\Private\Cluster.cpp in UE 5.5 ...

Get Material Instance ___ Parameter Value not working for Blend Parameter

UE - Rendering - Architecture - Materials - Dec 2, 2022

Reproduced 3/3 times, issue also occurs in //UE5/Release-5.0 - CL 20979098 Binary. Confirmed NOT a Regression. ...

Getting Fullscreen or Windowed Resolutions doesn't fully execute on Linux

UE - Rendering - Architecture - RHI - Oct 28, 2019

When using "Get Supported Fullscreen Resolutions" on UE when built with Vulkan, no values are printed out. This is an issue with any platform that builds UE with -vulkan, not just Linux.  In Engine ...

Anisotropy renders differently in each eye in VR

UE - Platform - XR - Jan 10, 2023

Regression: Tested in Release-5.0, this issue occurs so it is not a regression. This issue was first reported using the Automotive Materials assets, as the Anisotropy material on MI_Metal_Brushed w ...