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) ...

Html5 packaging fails on Windows if the user has HOME env var

UE - Platform - Mobile - Oct 3, 2016

If user has HOME env var, Html5 packaging creates .emscripten folder within the location specified by HOME, not the expected intermediate location(like C:\Program Files\Epic Games\4.13\Engine\Interm ...

X axis rotation only follows relative rotation

UE - Gameplay - Apr 10, 2017

A user is reporting that the X axis rotation appears to only rotate based on the object's relative rotation, and not rotate based on the world rotation, even when using Set world rotation. For test ...

Refraction Depth Bias In Material Instances Not Updating to Parent Materials Value

UE - Rendering Architecture - Materials - Aug 20, 2018

Refraction depth bias in Material Instances will not update to Parent Materials value. Found in 4.19 CL# 4033788, 4.20 CL# 4233996, and 4.21 CL# 4299102 Expected from user:Refraction Depth Bias sh ...

New VR-Basic level triggers Metal validation layer assertion

UE - Platform - Apple - Mar 16, 2020

This was discovered externally and reported on UDN here: https://udn.unrealengine.com/questions/563268/mac-editor-crash-when-disable-ambient-occlusion.html ...

Sun is rendered badly or not showing on mobile devices.

UE - Platform - Mobile - Jan 27, 2015

When you deploy the First Person Template to a mobile device, the sun will appear badly rendered or not rendered at all. Tested on iPhone5S, iPad Air, GalaxyS3 Mail, Nexus 6, iPad Air 2, Nexus 5, G ...

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 ...

Launch on for Win64 produces fatal error

UE - Foundation - Core - May 18, 2015

Creating a C++ project and then attempting launch on for Windows 64 causes a fatal error crash in 4.8 preview 2 binary from launcher. Project recovers from fatal error and can then package and run . ...

LIVE: LANDSCAPE: RENDERING: Landscape smooths until edited again after saving

UE - Graphics Features - Sep 15, 2014

Build: 4.4.2-2289767 Description: If a user makes changes to a landscape then saves the project, the landscape will appear smoothed until another change is made. Repro: [Reproduced Internally] 1. O ...

Crash after network disconnection/pulling network cable

UE - Networking - Jul 11, 2019

A very unfortunate bug shipped in 4.22 that causes a crash in many cases when a client is disconnected from the network, such as when unplugging the network cable. This will be a cert failure on con ...