Failed to build in Github UE4.27.0.

UE - Simulation - Physics - Aug 30, 2021

Failed to build UE4.27.0 with Win64/Development Editor.  Can avoid this error that excluding the project from build configuration. (Solution UE4->Properties->Configuration Properties->Configuratio ...

The results of Roughness=1.0 from a constant and from a parameter are different on 4.20.

UE - Graphics Features - Sep 4, 2018

The results of Roughness=1.0 from a constant and from a parameter are different on 4.20. The static bool switch of the following material always returns 1.0. But the results are different.[Link Rem ...

Raytraced lights with Source Length > 0 behave incorrectly with Megalights

UE - Graphics Features - Ray Tracing - Mar 26, 2025

When Megalights is enabled, light can leak into areas that should be occluded for lights with smallish (5.0) source length and source size. [Image Removed][Image Removed] This was taken with r.Ray ...

Editor will freeze if anim composite has an animation with a notify and length of 0

OLD - Anim - Mar 21, 2019

An anim composite will freeze the editor if one of its animation segments has a a notify and a length of 0 or less. Debugging shows that the engine is stuck inside UAnimSequenceBase::GetAnimNotifies ...

Ad banner is displayed incorrectly on Android 7.0 devices

UE - Platform - Mobile - Feb 24, 2017

GameActivity.java needs to be updated to show the ad popup window on Android 7.0 devices. GameActivity.java uses Gravity.BOTTOM or Gravity.TOP to place the ad. One thing to try would be to edit ...

Set user focus for player 0 will cause other local players to lose input

UE - Gameplay - Input - Feb 28, 2019

When the player at index 0 sets its user focus it will cause other players to lose input. This does not occur when setting the user focus of players with an index higher than 0. ...

Console command “showflag.rendering 0” causes crash

UE - Rendering Architecture - Jul 10, 2025

A crash occurs when the console command “showflag.rendering 0” is executed. This does not occur in UE5.5, so it is a iassue in UE5.6. ...

Linux: UI scale is sometimes not 1.0 on non-high-DPI monitors

UE - Platform - Linux - Nov 7, 2017

At the moment, UI scale is calculated on Linux from physical monitor dimensions (obtained ultimately from EDID) and not system scale. The granularity is 0.25, so scale can be 0.25, 0.5, 0.75, 1, 1.2 ...

Large snap scaling causes meshes to scale 0

UE - Editor - Workflow Systems - Mar 3, 2016

With a large snap scale just selecting the uniform scaler will make the content scale to 0. It seems like it is far too easy for meshes to accidentally be scaled to 0 with snap scaling. Another exa ...

[Voice Virtualization][Focus] - Looping sounds do not become Virtual when Virtualization is Restart and Volume Attenuation is set to 0 by Focus settings

UE - Audio - Voice Management - Sep 2, 2021

When using Voice Virtualization settings, if the Attenuation Volume becomes 0.0 do to Focus setting, Restart does not behave as expected on looping sounds. Both Disabled and Play when Silent do wo ...