StreamableManager completion callback can happen after being canceled in same frame

UE - CoreTech - Feb 16, 2024

FStreamableHandle (used as part of the FStreamableManager system) has a CancelHandle function that stops it from calling any completion callbacks related to that handle (it could cancel the load req ...

[CrashReport][GPUCrash] UpdateRadianceCaches

UE - Rendering - Graphics Features - Ray Tracing - May 19, 2025

#31 crash out of 7783 in UE 5.7.4 on Windows#3 crash for UE - Rendering - Graphics Features in UE 5.7.4 on Windows#1 crash for UE - Rendering - Graphics Features - Ray Tracing in UE 5.7.4 on Windows ...

Meshes with scaled root bones pop when entering simulation

UE - Simulation - Core - May 15, 2026

This issue is fallout from the changes in 33851494. Prior to that, we didn’t get the pop on beginning the sim. The problem appears to be that in USkeletalMeshComponent::PerformBlendPhysicsBones we ...

WorldCoordinate3Way produces Incorrect Axis Lerps

UE - Graphics Features - May 18, 2016

The Material Function WorldCoordinate3Way seems to incorrectly perform the Lerps from the axis contributions of the normals. An example is show here, with the left objects using the version that com ...

Deleting a Struct Attached to a Variable in a Blueprint Prevents it from Compiling

UE - Gameplay - Blueprint - Oct 20, 2015

Adding a variable of the type of a struct to a blueprint, deleting that struct, and then recompiling the blueprint fails. The variable is deleted, but the blueprint will continue to be unable to com ...

UMG Images Not Inheriting Texture's Filter Setting

UE - Editor - UI Systems - Dec 24, 2015

When you import a texture that is low resolution (such as pixel art) if you attempt to use it in a UMG image, the filter that you have applied to that texture is not inherited. This causes the image ...

This user's Function Library will not save

UE - Gameplay - Blueprint - Mar 6, 2015

This user's Function Library will not save. Hitting save returns the following error: Can't save D:/4.7_Projects/EngineTransientBug 4.7/Content/Math.uasset: Graph is linked to private object(s) in ...

Crash when adding multiple collision types to a mesh

Tools - Jan 27, 2017

Adding various collision types to a single mesh will cause it to hard crash the editor. No Crash Reporter window will open. Note that this happens with the user's mesh, but I was not able to repro ...

'Platform Stats' incorrectly display the number of Texture Calls for a material

UE - Rendering - Architecture - Materials - Jul 29, 2024

When the DBuffer is disabled in the project settings, the Material Editor Stat page will still display the estimated texture lookups for the DBuffer. It appears that the code that adds these estimat ...

Hang when using Debug config with Launch On to Android

UE - Platform - Mobile - Mar 18, 2019

Final bits of logging show:D/UE4 : [2019.03.18-16.36.59:236][ 0]LogInit: Display: Starting Game. D/UE4 : [2019.03.18-16.36.59:236][ 0]LogNet: Browse: /Game/FirstPersonCPP/Maps/FirstPerson ...