UClass::SparseClassDataStruct null at editor-time for child blueprints until compile

UE - Framework - Blueprint - May 29, 2024

Child blueprints of a blueprint of a native actor class with sparse data can have an incorrectly null SparseClassDataStruct value, and thus fail to initialzie their SparseClassData. This affects edi ...

VR Preview crash when shadow quality is set to low

UE - Platform - XR - Dec 5, 2024

[/Script/Engine.RendererSettings] r.Tonemapper.Sharpen=2 r.TemporalAA.Upsampling=False r.DefaultFeature.AutoExposure.ExtendDefaultLuminanceRange=True r.LightPropagationVolume=0 r.ReflectionCaptureRe ...

The AABBTree spatial acceleration structure goes off-sync when physics substepping is enabled in a "low" framerate environment.

UE - Runtime - Simulation - Mar 15, 2024

When you enable the physics substepping, if you run the console command p.Chaos.Solver.DebugDrawSpatialAccelerationStructure 1, you can see how does not follow the physical object. The user that rep ...

Assertion failed: (Index >= 0) & (Index < ArrayNum) when importing large Alembic file

UE - Editor - Open File Formats - Datasmith - Importer - May 3, 2022

Regression testing done on //UE4/Release-4.27.2 CL-18427296 and this issue did occur. [Link Removed] [Link Removed] Below is snips of customers description and proposed workaround:Importing alembi ...

Open Formats: glTF Import - importer truncates skeletal mesh bone influences to 4 per vertex

UE - Editor - Open File Formats - Aug 21, 2026

cf https://forums.unrealengine.com/t/interchange-gltf-importer-truncates-skeletal-mesh-bone-influences-to-4-per-vertex/2745391/2 Original message The UE5 Interchange GLTF importer appears to trunc ...

Blurry textures on BSP geometry when a very small static mesh using the same texture is in the same scene (standalone game)

UE - Graphics Features - Mar 9, 2020

The texture streamer does not appear to take into consideration the size on screen of any BSP brushes, only static meshes. When a large brush, and a very small static mesh, both using the same textu ...

Create staticmeshnode or instancedstatic mesh node logs FNetGUIDCache warning in editor

UE - Networking - Jan 3, 2019

The behavior in question involves a warning that FNetGuidCache gives when an Actor's construction graph adds a static mesh component, and a multiplayer session with 2 players is simulated in PIE.(Pl ...

Incorrect behavior after attaching an actor to a non-root component of another actor in the Editor

UE - Editor - Verse Class Editor - Jul 3, 2024

UE allows actors to be attached to other actors. More precisely, it allows the root component of an actor (child) to be attached to any component of another actor (parent). From now on, "parent" and ...

[CrashReport] Linux crash - /usr/lib/nvidia-375/libGLX_nvidia.so.0()

UE - Platform - Linux - Jul 27, 2017

This is a common Linux crash that has occurred since at least 4.14. From LogLogEditorViewport: Clicking on Actor (LMB): StaticMeshActor (pared_cubos15) LogRHI: Timed out while waiting for GPU to ...

Unable to add/compile code for Automation Test

UE - Automation Test - May 22, 2017

When following the documentation on setting up automation tests, the sample provided for "Simple Tests" does not successfully compile. One of two compiles errors is given based on the TFlag used A ...