Setting a value Material Parameter Collection to Material will cause crash

UE - Graphics Features - May 2, 2016

Adding a Material Parameter collection to a material, setting its value, then saving the material will cause a crash. This was only able to be reproduced on Mac and did not affect the Windows versio ...

OnClicked event of UMG button fires once in twice if virtual joystick is receiving input.

UE - Editor - UI Systems - Oct 14, 2015

OnClicked event of UMG button fires once in twice if virtual joystick is receiving input. Both Andorid and iOS devices are affected. This issue is found with 4.9 update. under 4.8 are fine. ...

Animation Track in Shot Does Not Animate With Evaluate Sub Sequences In Isolation Enabled

UE - Anim - Sequencer - May 15, 2018

When Evaluate Sub Sequences in Isolation is enabled in a shot, other shots inside the same sequences only play the transform track and do not play their animation track Does not affect 4.18.3 Relat ...

Disabling "Apply Fogging" Doesn't Work for Translucent Material with Volumetric Fog

UE - Graphics Features - Jul 6, 2018

Translucent materials with "Apply fogging" disabled will be affected by volumetric fog.  Found in 4.19 CL# 4033788, 4.20 Preview 5 CL# 4173640, and 4.21 ...

Default Values missing from Local Variables in Blueprint Actor Construction Script

UE - Gameplay - Sep 19, 2019

Specific to the Blueprint Construction Script, Local Variables cannot have their value set in the Editor, because the "Default Value" section of the Details tab will never appear. This only affects ...

Instance Materials are not Created When Importing an FBX

UE - Graphics Features - Oct 16, 2019

Instance Materials are not Created When Importing an FBX.  Found in 4.22 CL# 7053642, 4.23 CL# 8386587, 4.24 CL# 9551884, 4.25 CL# 9615021 ...

Engine Crashes When Converting an Int to Float For a Map Key In Blueprints

UE - Gameplay - Blueprint Editor - Dec 11, 2019

The engine crashes when trying to automatically create a type conversion node when they are used a key for a map. Found in 4.24 CL#10570792 Reproduced in 4.25 Main CL# 10646676 ...

Raytracing shadows and lighting not showing in rendertarget

UE - Graphics Features - Lumen - Dec 19, 2019

Raytracing shadows and light reflections not appearing in render target Tested in: 4.22.3 CL#7053642 4.23.1 CL#9631420 4.25 CL#10730208 ...

Materials using the Tessellation mode 'PN Triangles' cause objects to incorrectly render in Wireframe view mode when selected

UE - Rendering Architecture - RHI - Jan 21, 2020

Creating a material that has it's tessellation mode set to "PN Triangles" and assigning it to an object results in the objects geometry to not properly display in Wireframe view mode.  Tested i ...

Atan2() missing from Math Expression node

UE - Gameplay - Blueprint - Feb 11, 2020

Using the math expression Atan2(y,x) inside of a math expression node results in an error.  Tested in:  4.23.1 CL#9631420 ,  4.25 CL#11341939 ...