Material Editor Assertion Crash When Collapsing Material Attributes

UE - Rendering Architecture - Materials - Jul 14, 2022

Collapsed material attribute nodes cause an editor assertion crash in the material editor when viewed or opened. Assertion failed: (Index >= 0) & (Index < ArrayNum): Array index out of bounds: 0 fr ...

Fix center of mass calculations with welding.

UE - Simulation - Physics - Aug 25, 2016

Welding components uses precomputed weights for to determine center of mass for the actor. This can cause problems when users want to specify custom weights for certain components. ...

Fixing up GoogleVRHMD static analysis warning

UE - Platform - XR - Oct 31, 2016

[Line 1585] d:​\build​++ue4+release-4.14+compile​\sync​\engine​\plugins​\runtime​\googlevr​\googlevrhmd​\source​\googlevrhmd​\private​\googlevrhmdrender.cpp(42) : warning C6386: Buffer overrun while ...

Fix TSR velocity extrusion on rotating

UE - Graphics Features - Aug 3, 2023

Niagara Position Mode Unset results in World Space rather than Local Space

UE - Niagara - Scripting - Apr 16, 2025

When an emitter's Position Mode is Unset, the particles spawn in World Space 0,0,0. This is unexpected. If the Position Mode is Unset in 5.4, the particles remain in Local Space, which is the inten ...

Interpolators of Particle Dynamic Parameters Need "nointerpolation".

UE - Niagara - Aug 1, 2019

Regardless Niagara or Cascade, dynamic parameters for particles are passed to pixel shaders from vertex shaders via InterpolantsVSToPS. It can cause a precision error on some materials, for example ...

Infinite Loop When Generating HLOD Clusters

UE - World Creation - Worldbuilding Tools - HLOD - Aug 8, 2018

The HLOD system gets stuck in a infinite loop when building.  Comment from the user: ++I've tracked it down to this code: const AActor* UHLODProxy::FindFirstActor(const ALODActor* LODActor) { a ...

sphere collision with start and end points set to the same value return no hit objects

UE - Gameplay - Aug 29, 2016

Sphere collision with start and end points set to the same value return no hit objects. Workaround Set the end vector to 1 away from the start vector (0,0,0 to 1,1,1, etc.) Regression (no) issue ...

[CrashReport] UE4Editor_ClothingSystemEditor!UClothingAssetFactory::CreateFromSkeletalMesh() [clothingassetfactory.cpp:357]

UE - Simulation - Physics - Character - Aug 21, 2017

This is a trending crash occurring in 4.17 and 4.17.1. Users have not provided any descriptions of their actions when the crash occurred. Source Context 345 if(Params.bTryAutoFix && Param ...

[CrashReport] Ongoing CollectGarbageInternal() assertion in 4.17

Tools - Aug 22, 2017

This callstack is occurring in 4.17.0 and 4.17.1, and appears to be a continuation of [Link Removed], which was fixed in 4.16.2 with CL 3502786. I'm not re-opening [Link Removed] because there are ...