Nativizing a blueprint interface using TMap/TSet causes Fatal error in UHT

UE - Gameplay - Blueprint Compiler - Sep 9, 2020

FPropertyBase constructor does not handle a TMap/TSet property. Following workaround can avoid this error. explicit FPropertyBase(FProperty* Property) : PropertyExportFlags(PROPEXPORT_Public) ...

Duplicate slots being created in Anim Slot Manager

OLD - Anim - Dec 11, 2015

Duplicate slots are being created automatically under the Default Group in the AnimSlotManager. This is causing some problems because it replaces the originally created slot with the duplicate in t ...

Using Virtual Texture Streaming checkbox in texture editor can break materials

UE - Graphics Features - Feb 24, 2021

A texture can be toggled between virtual texture and regular texture using the Convert to virtual texture/regular texture tool in the texture asset context menu. This updates referencing materials t ...

Sequencer crashes when scrubbing characters with sub-anim instances and montage slots

OLD - Anim - Oct 2, 2019

I saw a following assertion. Assertion failed: (AdditivePoses.Num() > 0) || (NonAdditivePoses.Num() > 0) [Link Removed] [Line: 1381] This is my quick fix// code placeholder void FAnimInstance ...

Physics simulation shows strange behavior with specific skeletal mesh configurations

UE - Simulation - Physics - Mar 3, 2017

PhAT is inconsistent on when it does and doesn't apply scale to Constraint positions. This leads to cases where the positions provided create constraints that may not work when the Preview Skeletal ...

r.Shaders.Optimize=0 crashes when compiling a UI material

UE - Rendering Architecture - Materials - Sep 2, 2024

[2024.08.30-22.12.22:384][ 73]LogWindows: Error: appError called: Assertion failed: CurrentGPUVirtualAddress != 0 [Link Removed] [Line: 659] Disabling shader optimisation can crash the editor when ...

Assert when having too many VR devices

UE - Platform - XR - Aug 31, 2018

Internal team is encountering a crash when adding too many VR devices. Email thread titled "Re: Crash Logs" The bug is an internal limit of devices the code supports, which is 8. If a controller o ...

The engine crashes when adding a new brush at newly created level by a specific way.

UE - LD & Modeling - Modeling Tools - Mesh Editing - Jun 17, 2019

issuesFBSPOps::csgAddOperation returns null if BuilderBrush has no valid polys.The creating level on content browser never calls "UEditorEngine::InitBuilderBrush(NewWorld);". But "New level" button o ...

Adding a widget to a grid panel inside the grid panel tick can cause an out-of-bounds error

UE - Editor - UI Systems - Slate - Jan 25, 2021

This is caused by adding an item to a grid panel inside the grid panel iteration loop. The same operation to canvas panel goes well without any errors. The difference is that the array iteration in ...

BP hierarchy change triggers incorrect map actor load warning: AttachTo: '{0}' is not static {1}, cannot attach '{2}' which is static to it.

UE - Gameplay - Blueprint - Apr 11, 2024

When a blueprint's component hierarchy is changed by changing a child component's mobility value to Static while deleting its parent component which has Movable mobility, levels saved with an outdat ...