Different instanced materials are seen as the same material due to GUID

UE - Graphics Features - Jun 3, 2021

See licensee description of the issue: The problem appears when I have two instanced materials with the same number of parameters. I've noticed that ShaderMapId has MaterialLayersParameterIDs where ...

Mesh reduction modules selection aren't properly applied on engine restart

UE - World Creation - Worldbuilding Tools - May 4, 2023

Recent changes in the MeshReductionManagerModule::StartupModule() have introduced issues where it won't respect what reduction modules have been set in the config file. This is a big issue for plugi ...

SetMaterial allows the user to add a Material which updates the GetMaterials array but not GetNumMaterials

UE - Gameplay - Jan 15, 2015

SetMaterial allows the user to add a Material which updates the GetMaterials array but not GetNumMaterials. The user who reported this was trying to add a material to a skeletal mesh during runtim ...

UConsole HistoryBuffer no longer writing to disk in packaged builds

UE - CoreTech - Sep 7, 2023

We started running into issues with the console history not saving after upgrading to 5.2.1. The console history (as in the commands last input into the in-game console) is no longer being saved bet ...

Custom node not working with material attributes

UE - Rendering Architecture - Materials - Jul 15, 2024

Using Material Attributes as an input to a Custom Expression causes the HLSL Translator to create multiple CustomExpression# functions, for each used member of the Material Attributes, rather than u ...

Crash when playing with Vulkan Mobile Preview

UE - Platform - Mobile - Sep 21, 2017

Occasionally getting a crash when playing with Vulkan Mobile Preview. Have not had it repro 100% of the time. ...

Lightmass GI doesn't work with Material-based color changes

UE - Graphics Features - Sep 4, 2015

A licensee is having trouble getting the visual results they want because Lightmass doesn't seem to handle color changes from materials. They are seeing this in 2 cases: (See attached images and tes ...

Strange intermittent CCD behavior on constrained physics bodies

UE - Simulation - Physics - Oct 23, 2019

There is some strange issue with CCD where constrained CCD objects can get velocity nulled when hitting things while constrained, its very hard to reproduce normally in engine but happens often in V ...

Crash calling destroy actor for Geometry Collection while it's simulating

UE - Simulation - Physics - Destruction - May 12, 2020

Crash occurs when user call Destroy Actor on a Geometry Collection Actor. This seems to only occur while the actor is simulating. If called while on the ground, it doesn't seem to occur. ...

Editor crash when compiling blueprint that contains an implemented interface after removing return node

UE - Gameplay - Blueprint - Apr 8, 2015

If a return node is removed from an interface that has been implemented in a blueprint, compiling the blueprint will cause a crash. Crash Reporter: [Link Removed] Frequency: 2/2 ...