Chaos : Rigid body sleeps when very small external force is applied by AddForce

UE - Simulation - Physics - Solver - May 25, 2022

When a small external force is applied to the rigid body, the VSmooth value is reset in the ResetVSmoothFromForces function. Since this function ignores the current velocity, a very small velocity ...

In 5.6, bWarningsAsErrors does not work with clang

UE - Foundation - Cpp Tools - UnrealBuildTool - Sep 20, 2025

In 5.6, many warnings and errors specify their command line arguments to the compiler with these new C# attributes:    [WarningsClangToolChain(["-Wno-date-time"], ["-Wdate-time", "-Wno-error=date-ti ...

Attempting to use the GameplayTags module in a binary code project will result in build failures in Visual Studio.

UE - Foundation - Core - Mar 27, 2015

Using the GameplayTags module in a code project created with the binary version of the Engine results in a build failure in Visual Studio. The following error is shown: 1> D:/Epic Games/4.7/Engine ...

Direct Capsule Shadows with Point Lights also project shadow on opposite side and direction

UE - Graphics Features - Dec 14, 2016

When using a Direct Capsule Shadows on a skeletal mesh with a Stationary Point light, depending on the point lights placement, light source radius, and nearby surfaces will cast the shadow on the op ...

Gradual drop in Performance on Windows 10 projects after Toggling Fullscreen

Tools - Nov 30, 2015

It seems that when working in any project on a Windows 10 machine, there is a gradual rise in frames per second and a consistent drop in performance. The user reporting this issue claims his frame ...

[CrashReport] Assertion failed: !PinRef->bWasTrashed | UEdGraphPin::SerializePin()

UE - Gameplay - Blueprint - Aug 29, 2017

This is a common and longstanding crash that has occurred since at least 4.15 and affected nearly 500 users. The CrashGroup was previously linked to [Link Removed], but that had specific repro step ...

LIVE: Setting sg.EffectsQuality between values will reset Destructible meshes if they have fractured

UE - Simulation - Physics - Destruction - Nov 14, 2014

DESCRIPTION: Using the command line sg.EffectsQuality and setting a value will reset a destructible mesh if it has already been fractured. AH Post: https://answers.unrealengine.com/questions/12850 ...

Details panel for Actor Component is blank in any Blueprint that derives from a code class using that Actor Component after the Actor Component's class name is changed

UE - Gameplay - Blueprint - Dec 20, 2018

Changing the name of an Actor Component code class in a project results in any existing Blueprints that derive from code classes that use that Actor Component to not display the Actor Component's pr ...

Failed to generate Nanite data for mesh with bDoFastBuild enabled

UE - Graphics Features - Nanite - Oct 1, 2025

If "bDoFastBuild" is enabled on a Static Mesh asset, in-editor it will never be able to have Nanite data built for it, preventing the Static Mesh from using Nanite. There is no way to fix this issu ...

Packaging Error When Setting Recast Nav Mesh Runtime Generation

UE - AI - Jan 25, 2016

Setting the Runtime Generation on the Recast Nav Mesh to a different preset than what is set in the Project Settings causes an error to appear upon trying to package the project, and causes the pack ...