Landscape Splines in Partially Loaded World Partition Levels Can Cause Nanite Landscape Invalidation

UE - Graphics Tools - Terrain - Nov 7, 2025

Certain placements of landscape splines in world partition levels can cause Nanite landscape proxies to invalidate, and switch back to their non-nanite version. This happens when specific regions of ...

IPA Package Sizes have Increased between Versions

UE - Platform - Mobile - Feb 21, 2017

When packaging for iOS the IPA file seems to have increased in size from previous versions. The licensee made an important observation that it appears the master materials have almost halved in si ...

Tabbing out of exclusive fullscreen leaves the window & backbuffer in an incorrect state

UE - Editor - UI Systems - Apr 24, 2020

With windows 10 there has come some new swap chains, which unfortunately messes some things with regards to fullscreen up. We've fixed a bunch in the renderer (which would downright cause crashes), ...

Increase in Engine Stats for large amounts of Hierarchical Instanced Static Mesh Components

UE - Graphics Features - Apr 18, 2017

Increase in Engine Stats for large amounts of Hierarchical Instanced Static Mesh Components User Description: We are having performance drops of almost 5ms in 4.15 when using "Hierarchical Instanc ...

Possible data loss/corruption when loading levels in editor

UE - Gameplay - Jul 18, 2018

Reported behavior: Given Level_A which contains object_X, where object_X references Level_BDeleting object_X causes AssetRenameManger to check if we need to patch up other levelsLevel_B is load ...

Failure to sign when packaging for iOS Distribution when using Remote Compile from a code project on Windows

UE - Platform - Mobile - Feb 20, 2019

Packaging for iOS Distribution from Windows using Remote Compile results in a failure during the signing portion. This seems to be caused by a hardcoded "false" for a property that is used to determ ...

SketchUp UV scale is not consistent for Datasmith imports.

TM - Interoperability - Dec 6, 2024

This is not a regression.  We have 2 issues here.  First we have different tiling for the different materials, since the way sketchup handles texture scale. They scale the UVs of the object instead ...

PCG sampling of RVT does only works when sampling the first texture layer

UE - World Creation - Procedural Tools - PCG Component - Dec 11, 2025

The 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 ...

References to Data Assets that inherit from Blueprints may be broken during reinstancing

UE - Gameplay - Blueprint - Nov 30, 2020

It is possible to create new Data Asset instances in the editor that inherit from a blueprint-defined subclass of UDataAsset. This flow is not very well supported, and generally it is safer to just ...

Editor crash when opening Project Settings on Linux

UE - Platform - Linux - Mar 29, 2017

When the Project Settings is opened on Linux, a call is made to run an iOS-related C# program (execute iPhonePackager certificates). This call causes the editor to crash. Unable to find mention of ...