UNetDriver server-side hitch results in ActorInfo->NextUpdateTime far into future

UE - Networking - Feb 16, 2024

A high UWorld::Tick DeltaSeconds (i.e. GameThread hitch) results in a high UNetDriver::TickFlush DeltaSeconds. This DeltaSeconds can high (many seconds) if the hitch is long. This value then affects ...

Exporting Mannequin to Blender then Re-importing to UE4 Incorrectly Rotates Animations by 90 Degrees

OLD - Anim - Jun 16, 2015

Exporting the UE4 Mannequin to Blender then re-importing to UE4 breaks the animations, causing them to reimport rotated 90 degrees ...

Animation Orientation does not Auto-Convert to UE4 Coordinates when Reimporting

OLD - Anim - Nov 23, 2015

Animation orientation does not auto-convert to UE4 coordinates when reimporting the same way it does when importing the same animation as a new import. In other words, a run animation generated from ...

BulkData Async loading remains in memory

UE - Foundation - Core - Oct 26, 2016

Gil's new loading path may already walk away from this issue. But here's some thing I tested locally if we want to fix this. A simple way to fix is to simply add BulkDataAsync.Deallocate(); ResetA ...

[CrashReport] FLandscapeEditorCustomNodeBuilder_TargetLayers::OnTargetLayerDeleteClicked()

UE - LD & Modeling - Terrain - Landscape - Oct 5, 2017

This is a somewhat common Landscape crash occurring throughout the 4.17 release. User Descriptions1) rename landscape layer, 2) delete layer in landscape tool Source Context 1307 FReply FL ...

Navmesh doesn't work in a Packaged Build if it was placed in a Sublevel

UE - AI - Oct 19, 2018

Once packaged, a persistent level is unable to create navmesh data properly if the navmesh bounds volumes are only present in its sublevels. The issue can be traced to the UNavigationSystemV1::IsThe ...

AbilitySystemComponent::NotifyAbilityEnded Can Crash due to Callbacks Invalidation Specs

UE - Gameplay - Gameplay Ability System - Oct 11, 2023

Pasting from the UDN: Unsafe code in AbilitySystem can lead to crash when granting an ability inside OnAbilityEnded Hello. We just ran into a crash. After investigation, it seems to be caused by ...

Crash with assigning APEX Cloth that uses a custom graphical mesh

UE - Simulation - Physics - Feb 24, 2015

When a graphical mesh is used to create a lower LOD for cloth assets and the Cloth FBX has the APB assigned to the material for the cloth there will be a crash. ...

"Error Provision not found" even though the provision is present and valid in 4.13.1

UE - Platform - Mobile - Oct 31, 2016

A few users are reporting on the Answer Hub and in the Forums that they are getting the following error in their output logs: "Error Provision not found" even though the provision is present and va ...

Crash Opening Editor with Vulkan - Fatal Error - RenderingThread.cpp

UE - Rendering Architecture - RHI - Mar 15, 2019

Editor crashes when opening to project browser on Linux. Fatal error: [File:D:\Build\++UE4\Sync\Engine\Source\Runtime\RenderCore\Private\RenderingThread.cpp] [Line: 819] Rendering thread exceptio ...