Data loss caused by C++ Child Actor Component when compiling Child BP

UE - Gameplay - Blueprint - Dec 22, 2016

Having Child Actor Components that are set in code can cause data loss upon compiling the blueprint. In this particular scenario, there are two custom Actor classes involved, MainActor and SubActo ...

Null Material Layers in Material Instances cause Opacity Mask and WPO to break on Nanite Meshes

UE - Rendering Architecture - Materials - Oct 31, 2024

When a Material Instance is loaded that has a nullptr layer in StaticParametrs.Materiallayers.  The Material Instance will create it's own CachedExpressionData but the ConnectedParameterMask will be ...

[CrashReport] UE4Editor_CoreUObject!UObjectPropertyBase::CheckValidObject() [propertybaseobject.cpp:510]

UE - Gameplay - Blueprint - Sep 28, 2017

This is a trending crash after the 4.17.2 hotfix, but has occurred since 4.17.0. Users have not provided any description of their actions when the crash occurred. The callstack shares similarities ...

Visual Studio opens unnecessary windows when adding a new C++ class via the editor's interface

Tools - Oct 25, 2017

When adding a new C++ class to a project via the editor's interface, Visual Studio is opened but it ends up opening more than is necessary. Firstly, Visual Studio is opened without focus on the two ...

Crash launching ES31 app on Android

UE - Platform - Mobile - Apr 9, 2018

This has occurred so far using ES31 with Launch On to Android. It didn't occur with ES2 or Vulkan.Error: === Critical error: === Error: Error: Fatal error: [File:D:\Streams\Fortnite_Staging\Engin ...

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), ...

Staging Directory in Project Packaging Settings should not be saved as absolute path

UE - Foundation - Data Pipeline - Cooker - Jun 8, 2021

When you package a project via the editor, it updates the ProjectPackagingSettings to set the StagingDirectory to the specific one chosen by the user. However, it saves this path as an absolute path ...

[UDN-19505621] Hide Selected At Startup Issue

UE - Editor - Workflow Systems - Jun 10, 2025

From [Link Removed]: 你好,我发现这里的选项有一些工作逻辑不一致,提一个改进建议: ​ 当手动隐藏Actor小眼睛图标的时候,设置Hide Selected At Startup 是无效的,这具有很大的误导性,而其他任何情况下,工作都是正常的,比如: 1.小眼睛隐藏+Show All At Startup 2.小眼睛隐藏+Show Selected At Startup ...

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 ...

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, 2024

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, so from the location of the new asset's the relati ...