AR Core - Apps with Candidate image result in black screen on first launch

UE - Platform - XR - Jan 20, 2020

On first launch of an AR app with Android the camera passthrough will render black. This also happens if an app is minimized and re-opened. This will not repro if there is no candidate image assign ...

Problem with material layers using interpolator nodes

UE - Rendering Architecture - Materials - Jun 7, 2024

The Vertex Interpolator Material Expression appears to collapse separate instances from separate Material Layers, leading to visual artifacts when used. Also tested on UE5_Main, CL: 34200103 ...

Invalid DumpGPU capture when ProjectDisplayedTitle contains special utf8 chars

UE - Graphics Features - Mar 7, 2025

Placing a special UTF-8 character into the "ProjectDisplayedTitle" will result in GPU dumps failing to open. This appears to be because the dump will switch between us-ascii and UTF-16 file formats ...

[CrashReport] UE4Editor_SlateCore!FHittestGrid::GetBubblePath() [hittestgrid.cpp:145]

UE - Editor - UI Systems - Slate - Oct 27, 2017

This is a trending crash coming out of the 4.18 release. Users have not provided any descriptions of their actions when the crash occurred. Based on the affected project names, this crash seems co ...

Orientation Warping breaks incoming poses where bones are in component space

UE - Anim - Gameplay - Apr 17, 2025

The orientation warping node breaks incoming poses where bones are already in component space. This is because, in EvaluateSkeletalControl_AnyThread, we are repeatedly setting bone transforms direc ...

Custom Primitive Data color widget not applying correctly to static mesh components in Blueprint editor.

UE - Rendering Architecture - Materials - Jul 23, 2025

Context Custom Primitive Data is used to store custom data in an index array that is accessible through Blueprint and code. This allows for variations across instances of the same mesh without needi ...

Crash after adding an AI Perception component to a parent and child character

UE - Gameplay - Sep 14, 2017

Crash after adding an AI Perception component to a parent and child character. First they both must have had AI Perception components > Compiled and saved > Then both AI Perception components delete ...

Reference to control rig can be lost on actors with multiple skeletal mesh components

UE - Anim - Rigging - Control Rig - Apr 4, 2023

In the attached project, when we initially add a control rig track for the actor with multiple skeletal mesh components, we add the control rig for the correct component because FControlRigParameter ...

Light Function and World Position in 5.4

UE - Graphics Features - Nov 4, 2024

When rendering a Light Function into the Translucency Lighting Volume, the World Position Material Expression returns the position relative to the Camera (unrotated), not the World. This can be mor ...

Scene Capture 2D will default back to View 0

UE - Graphics Features - Oct 8, 2015

The scene capture will revert back to the Character BP that is placed in the level when player 2 is not moving. When they are moving the scene captuer will show correctly. You can get around this ...