Replication issues & warnings if a client hitches while the server seamless travels

UE - Networking - Jul 28, 2020

If a client hitches while a server performs a seamless travel, the client will get multiple lines of logspam of these warnings:Warning: UActorChannel::ProcessBunch: SerializeNewActor failed to find/ ...

Skeletal mesh reduction - Material settings are lost when regenerating the LOD in a mesh with a reduced material section

UE - World Creation - Worldbuilding Tools - HLOD - Nov 25, 2020

Following code fixes this issue in FQuadricSkeletalMeshReduction::ReduceSkeletalMesh Section.ChunkedParentSectionIndex = bIsChunkedSection ? CurrentParentSectionIndex : INDEX_NONE; // ...

Final Gather Quality Post Process setting causes severe rendering issues in the Stack-O-Bot project

UE - Graphics Features - Lumen - Feb 24, 2022

When opening the Stack-O-Bot project in 5.0 Preview 1, the project has a rendering issue where bright shimmering lights appear all around the screen. I discovered that this is due to the PostProcess ...

CreateDynamicMaterialInstance will pull from the base rather than overridden mesh on SkinnedMeshComponent when run from construction script

UE - Framework - Blueprint - Feb 6, 2025

When UPrimitiveComponent::CreateDynamicMaterialInstance is called on a skinned mesh, and the input material is invalid, we call USkinnedMeshComponent::GetMaterial to get the base material on the exi ...

Crash when exporting static mesh actor to FBX (Array index out of bounds)

UE - Editor - Content Pipeline - FBX - Apr 25, 2025

I set the Forced LOD Model on the mesh component > 1, then tried to export, this is what causes the crash. Here is my suggested fix, we just don't use Git or I'd do a PR: In the else() branch of FF ...

Particle emitter Depth Fade node isn't accurate on iOS

UE - Platform - Mobile - May 18, 2017

Particle emitter Depth Fade node isn't accurate on iOS. When set to a normal value (around 100) it will fade out at about 65,000 units away from the particle. Licensee Description: we use a partic ...

SetPhysMaterialOverride does not work properly when using Weld Simulated Bodies enabled AttachToComponent func

UE - Simulation - Physics - May 7, 2019

When using Weld Simulated Bodies enabled AttachToComponent func, the child Primitive Component's BodyIstance ActorHandle is released. As a result, in BodyInstance.cpp, the judgment of FPhysicsComman ...

Complex collision mesh might lose its collision in the editor

UE - LD & Modeling - Modeling Tools - Mesh Editing - Feb 18, 2020

This is affected by loading order. In the case, display mesh was loaded firstly and try to build collision mesh form complex collision mesh asset. But the collision mesh didn't finished to make Ren ...

Actor variable type has distractingly large tooltip comment

UE - Gameplay - Blueprint Editor - May 4, 2021

Actor.h has a large comment that describes the entire lifecycle of Actors, which was written for the API website (https://docs.unrealengine.com/en-US/API/Runtime/Engine/GameFramework/AActor/index.ht ...

LLM PlatformProcessMemory calculation ignores VRAM, and its calculation of how much memory is used by the process is too low

UE - Foundation - Sep 29, 2023

FLowLevelMemTracker::TickInternal() the ELLMTag::Total (and therefore ELLMTag::Untracked) memory amounts are calculated based only on the result of FPlatformMemory::GetStats(), which on the Windows ...