Unreal Engine Issues
Unreal Engine Issues
NPC - Does not get updates from Material Parameter Collection changes in the editor
UE - Niagara - Sep 30, 2024When an MPC is selected as the Source Material Collection for an NPC, all of its current parameters are carried over to the NPC with their current values. After that, if parameters are added to, rem ...
Crash when Live Coding is triggered after engine source edits Blueprints using ChildActorComponent
UE - Framework - Blueprint - Nov 28, 2025After editing engine source files and triggering Live Coding, derived Blueprints that inherit from a Blueprint containing a ChildActorComponent cause UChildActorComponent::Serialize to run on a Live ...
Preview Rendering Levels Do Not Display Supported Optimization Viewmodes in Viewport Dropdown
UE - Platform - Mobile - Apr 2, 2019When attempting to set an optimization viewmode while using a Preview Rendering Level other than Shader Model 5, the Optimization Viewmodes dropdown is missing all of its options and instead display ...
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, 2019issuesFBSPOps::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 ...
PCG sampling of RVT does only works when sampling the first texture layer
UE - World Creation - Procedural Tools - PCG Component - Dec 11, 2025The logic for selecting a page table texture in FVirtualTexturePageTable::Initialize() uses the indexing for texture layers (index 0-7) to fetch from the page table textures (index 0-1). All RVT for ...
An imported file that resides within the project's folders gets a relative path. That path is not updated it you copy the uasset to another folder. That breaks the Reimporting functionality.
UE - Editor - Content Pipeline - Import and Export - Aug 28, 2024An imported file that resides within the project's folders gets a relative path. That path is not updated it you copy the uasset to another folder, so from the location of the new asset's the relati ...
Crash when adding Actor Array Element to a Sequencer Event Struct
UE - Anim - Sequencer - May 25, 2017Crash when adding Actor Array Element to a Sequencer Event Struct Error message: Assertion failed: 0 [Link Removed] [Line: 56] Source Context: 42 N = FName(*StringName); 43 ...
[CrashReport] UE4Editor_SlateCore!SWindow::GetLocalToScreenTransform() [swindow.cpp:737]
UE - Editor - UI Systems - Slate - Oct 27, 2017This is a trending crash coming out of the 4.18 release. Users have not provided any descriptions of their actions when the crash occurred. Source Context 724 FGeometry SWindow::GetWindowG ...
Users can't change flags on asset entries in PSD when the asset was added via a Branch In notify
UE - Anim - Gameplay - Mar 19, 2025Assets added to a PSD via a Branch In notify can't have their flags changed within the database. When the flags (like mirror, disable, etc) are changed, they revert back to the original value when ...
LevelEditor: "Replace Actor" marks level as dirty even when using external actors
UE - World Creation - Worldbuilding Tools - Jul 15, 2024When using external actors, adding/removing/replacing/editing an actor instance inside a level does not cause any modification to the Level package, which helps reduce contention for the map file on ...