Depth reading features on devices without framebuffer fetch are relying on undefined behaviour.

UE - Platform - Mobile - Oct 26, 2016

For devices without framebuffer fetch we are relying on undefined behaviour for depth reading with decals, mod shadows and depth reading materials. (ES2 spec: 3.8.6 Texture Framebuffer Attachment). ...

Collision between physicalized actors and instanced static meshes produce warnings.

UE - Simulation - Physics - Sep 25, 2023

Collision between an instanced static mesh and a physics simulating actor (with "simulation generates hits events" enabled) results in the following warning: LogChaos: Warning: Collision handler en ...

Native gameplay tags in plugins are cleared when reading config files

UE - Gameplay - Aug 14, 2024

When references to Gameplay Tags are loaded, it checks to see if they are already registered. If they are not already registered, it will notice it is invalid and may print a warning depending on th ...

OnActive Gameplay Cues not activating properly in standalone

UE - Gameplay - Nov 28, 2016

This was reported from https://udn.unrealengine.com/questions/323255/bugfix-onactive-not-triggering-for-gameplaycues-on.html In some case it looks like OnActive gameplay cues are not working proper ...

Editor crash on level load when bUseActorFolders is true after dragging Actor into another folder in the Outliner

UE - World Creation - Worldbuilding Tools - OFPA - Mar 7, 2023

From licensee: Hello! Our level streaming setup enables the bUseActorFolders on our levels. When moving the Actor into another folder via the Outline, the editor will crash on the next load Assert ...

Physics Constraints have unexpected behavior when used on nested static mesh components

UE - Simulation - Physics - Jul 5, 2017

Physics Constraints have unexpected behavior when used on nested static mesh components. Simulating inside of the blueprint has a similar effect to what is expected but when the BP is added to the l ...

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 ...

RVT output from Landscape Height gets incorrect mip cache loaded

UE - Graphics Features - Oct 13, 2021

I test it for more information for your reference:It happens only when a Landscape *Height *was output to the RVT, other Landscape's maps like BaseColor are all fine, as well as Height output from o ...

Light as If Static setting does not Persist when Re-opening Project

Tools - Apr 28, 2016

This bug was originally entered back in 4.8 as [Link Removed], but was closed as by design. The reason was, the mesh did not have Lightmap UVs, so using the 'Light as If Static' option would not wor ...

HLODs appear dark/near black when built for very large geometry with Virtual Textures enabled

UE - World Creation - Worldbuilding Tools - HLOD - Jan 27, 2025

Building HLODs for a very large landscape with Virtual Textures enabled results in the built HLODs being very dark for the most part. Building the same large landscape's HLODs with Virtual Textures ...