Loading Duplicated Level via Python API Crashes Editor

UE - Editor - Workflow Systems - Feb 16, 2023

When called from Python, in 5.1 the load level invocation results in a kernel panic style crash of the editor, with a message about the map leaking memory and not being able to be garbage collected ...

Mobile VR - Foliage (HISM) crash

UE - Platform - XR - Jun 7, 2019

HISMs cause mobile VR app to crash. Confirmed in 4.23 MAIN @ CL 6829265 ...

GPU Crash in Niagara Fluids template when WorldSpaceSize has a component at 0

UE - Niagara - Apr 26, 2024

The NiagaraFluids plugin provides several Niagara System templates to use as a starting point for the user's own Systems. The templates in category "3D Gas", such as "Grid 3D Gas Explosion", include ...

TMap Contains Node Returns False Incorrectly Under Specific Circumstances

Tools - Nov 20, 2019

The Contains node doesn't return an existing row from a data table under specific circumstances. This didn't occur when the struct the data table is based on was made via blueprints or there are mor ...

UClass::SparseClassDataStruct null at editor-time for child blueprints until compile

UE - Framework - Blueprint - May 29, 2024

Child blueprints of a blueprint of a native actor class with sparse data can have an incorrectly null SparseClassDataStruct value, and thus fail to initialzie their SparseClassData. This affects edi ...

Thirdperson Character not Replicating correctly after being attached to an Actor

UE - Networking - Dec 20, 2017

Problem description: When the Third Person Character gets attached to any other Actor (AttachToActor, Rule: Keep World), from the view of other clients the character (capsule, skeletal mesh) is out ...

Sequencer fails to package during Build command for ASTC

UE - Platform - Mobile - Jan 15, 2017

When attempting to test for ESDSR on Android, the Sequencer project fails to package towards the end of the Build Command. Runtime/OpenGLDrv/Public\OpenGLESDeferred.h(267,5) : warning: 'OPENGL_ES2 ...

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 ...

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 ...