Missing PSO Precaches in the engine

UE - Rendering Architecture - RHI - Aug 20, 2025

A licensee wanted to report some missing PSO Precaching they found, which they have fixed locally: 1. UCableComponent doesn't implement CollectPSOPrecacheData or call CheckPSOPrecachingAndBoostPri ...

FPS Perf Regression on 980

UE - Graphics Features - Mar 17, 2015

At least one user has so far reported a noticeable drop in FPS from 4.6.1 to 4.7.2 in a heavy scene; using a GTX 980. I've reproduced a perf drop in a cooked 4.7 build of elemental demo compared to ...

[CrashReport] GPUCrash - exiting due to D3D device being lost - D3D Hung - Nvidia

UE - Graphics Features - May 14, 2019

Separating [Link Removed] into Nvidia and AMD tickets.This ticket will house Nvidia information Exported data on 5/14/2019 with following Query:1 Month Time FrameMajorVersion is 4.22.1Callstack Con ...

Lighting channels not working as expected when enabling Ray Tracing Shadow

UE - Graphics Features - Lumen - Oct 13, 2020

Non-Ray Tracing Shadows are only cast from lights on meshes assigned to the same Lighting Channel. When enabling Ray Tracing Shadows this is not the case. Lights will still cast Ray Tracing Shadows ...

Variant manager crash in UPropertyValue::HasValidResolve

UE - Editor - Content Pipeline - Variants - Nov 21, 2024

in the past we have reported a lot of VM related bugs which got fixed over time. Unfortunately, I think we have another one. Right now we're using 5.0.3 binaries from the launcher. Now the pro ...

Multiple setter functions in UMaterialEditingLibrary always return false even when the parameter is correctly set on the MaterialInstance.

UE - Rendering Architecture - Materials - May 30, 2025

In Unreal Engine, materials can expose parameters that can then be modified via instances (MaterialInstanceConstant). The UMaterialEditingLibrary provides several functions to modify these parameter ...

Creating a new C++ Synth Component results in a failed compile linker error.

UE - Audio - Dec 19, 2019

Upon creating a new Synth Component C++ Class in Unreal 4.24, the compiler will fail to compile with a Linker error. ...

Empty Shot Track Breaks Camera Component tracks when using Camera Cut Track

UE - Anim - Sequencer - Aug 18, 2016

Empty Shot Track Breaks Camera Component tracks when using Camera Cut Track ...

Physics object resting on movable platforms have erratic physics behavior in 4.14

UE - Simulation - Physics - Dec 14, 2016

Physics object resting on movable platforms have erratic physics behavior in 4.14. This is a regression from 4.13.2-3172292 User Description: When placing more than 10 or 20 blocks on a moving pl ...

[CrashReport] UEdGraphPin::Modify - UEdGraphSchema_K2::RecombinePin

UE - Gameplay - Blueprint - Sep 7, 2017

This is a somewhat common crash affecting users in 4.17. Users have not provided any descriptions of their actions when the crash occurred. Source Context 606 void UEdGraphPin::AddStructRe ...