Combining Layered Blend Per Bone with Cached Pose nodes can break root motion extraction

UE - Anim - Gameplay - Aug 23, 2023

When the input to a Layered Blend Per Bone node is two instances of the same cached pose, we aren't sampling root motion correctly.  In the attached example, the weight on the root bone is 0 and Ble ...

"Enable Stencil Test" Mobile crash

UE - Graphics Features - Sep 10, 2019

A material with 'enable stencil test' will crash on mobile. Enable Stencil Test is a new option in materials as of 4.23 Confirmed with OpenGL 3.1 + 2 and Vulkan on Pixel XL Also Crashes on iOS ...

Scene Color node with UV input on a transparent material renders incorrectly in stereo

UE - Platform - XR - Jan 19, 2021

From Licensee: When we have Instanced Stereo enabled, all our materials that use Scene expression nodes (SceneDepth, SceneColor, etc...), render incorrectly in the right eye. It only happens to the ...

Possible incorrect pointer manipulation in BeginPackageCacheForCookedPlatformData

UE - Foundation - Core - Cooker - Dec 12, 2017

In UCookOnTheFlyServer::BeginPackageCacheForCookedPlatformData(), there is a pointer to int32 called CurrentAsyncCache that is used as an index. It's value is dereferenced before it is checked, but ...

Exporting Mannequin to Blender then Re-importing to UE4 Incorrectly Rotates Animations by 90 Degrees

OLD - Anim - Jun 16, 2015

Exporting the UE4 Mannequin to Blender then re-importing to UE4 breaks the animations, causing them to reimport rotated 90 degrees ...

Control Rig - Undo doesn't function correctly with proxy and multi bone controls

UE - Anim - Rigging - Control Rig - Oct 26, 2025

Issue from my Technical Animator where the undo operation in Control Rig doesn't work as expected on Proxy Controls. He has recreated the issue using the "Control Rig Samples Pack" and recorded a vi ...

[CrashReport] UE4Editor_Slate!FMenuStack::DismissInternal() [menustack.cpp:582]

UE - Editor - UI Systems - Slate - Apr 15, 2016

Error Message: Assertion failed: (Index >= 0) & (Index < ArrayNum) [Link Removed] [Line: 785] Array index out of bounds: 1 from an array of size 0 Source Context: 567 } 568 } 569 ...

Crash when launching Google VR project

UE - Platform - XR - Dec 12, 2016

Attempting to launch a packaged Google VR game on android causes the game to crash. This has occurred on two other devices. This occurs in Main as well as Dev-VR. ...

Crash on Linux and Windows with Vulkan when adding Atmospheric Fog to a Level

UE - Graphics Features - Dec 5, 2018

Adding an instance of Atmospheric Fog to a Level causes the Editor to crash on both Linux and Windows when using Vulkan. There is a different callstack when SteamVR is enabled on Linux which is also ...

[Metal-Epic:Tools] Compiling Metal 2.0 shaders on XCode 9.3 beta with desktop forward selected fails on iOS

UE - Graphics Features - Mar 30, 2018

Shaders fail to compile with a series of cube map errors (subset below): LogShaderCompilers: Warning: 17 Shader compiler errors compiling global shaders for platform SF_METAL_MRT:   LogShaderComp ...