Long thin spinning objects take too long to stop spinning

UE - Simulation - Core - Jun 5, 2023

See the SpinningObjectStability test map in the Physics Sandbox. [Link Removed] It's not clear if this is a bug or a side effect of some of our solver shortcuts (e.g., omission of the precession te ...

FBX animations generated under fractional framerates fail to import

UE - Anim - Runtime - Aug 24, 2022

We now have the following error that is generated in FFbxImporter::ValidateAnimStackif (!FMath::IsNearlyZero(SubFrame, KINDA_SMALL_NUMBER) && !FMath::IsNearlyEqual(SubFrame, 1.0f, KINDA_SMALL_NUMBER ...

Disabling bLerpUVs in Nanite Settings of Static Mesh causes texture warping in clusters

UE - Rendering - Graphics Features - Nanite - Jan 21, 2025

The licensee has identified a potential fix by changing if( Settings.bLerpUVs ) to if( Settings.bLerpUVs || UVIndex == 0 ) On line 389 of NaniteBuilder\Private\Cluster.cpp in UE 5.5 ...

Get Material Instance ___ Parameter Value not working for Blend Parameter

UE - Rendering - Architecture - Materials - Dec 2, 2022

Reproduced 3/3 times, issue also occurs in //UE5/Release-5.0 - CL 20979098 Binary. Confirmed NOT a Regression. ...

Anisotropy renders differently in each eye in VR

UE - Platform - XR - Jan 10, 2023

Regression: Tested in Release-5.0, this issue occurs so it is not a regression. This issue was first reported using the Automotive Materials assets, as the Anisotropy material on MI_Metal_Brushed w ...

Buoyancy is broken in UE5: even BP with Cube SM component (mass is 1kg) and default Buoyancy Component with one default Pontoon falls on bottom of lake

UE - Simulation - Visual - Jul 26, 2021

Shorter steps:Steps 1-8 from Steps to reproduce (create level with water body)Find BP_BuoyancyExample in Content Browser (Engine>Plugins>Water Content>Blueprints)Place BP_BuoyancyExample above the w ...

UAnimNotify::Notify not called during USkeletalMeshComponent interaction with UPhysicsControlComponent when PhysicsBlendWeight is zero

UE - Anim - Synthesis - Physics Control - Mar 30, 2025

UAnimNotify::Notify not called during USkeletalMeshComponent interaction with UPhysicsControlComponent when PhysicsBlendWeight is zero. The licensee has provided his analysis of the code: If USkelet ...

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 ...

Using the end of the curve as a weighted tangent does not yield the expected value.

UE - Anim - Runtime - Oct 16, 2023

When changing the tangent value, the last value is sometimes not 1.0 [Reproduce sample project] [Link Removed] ...

BlendListByEnum assumes that enum values are sequential

UE - Anim - Runtime - Anim Blueprints - Aug 26, 2024

FAnimNode_BlendListByEnum assumes that values within a custom enum type are sequential (ie. the index 0 = value 0, index 1 = value 1).  But this is not true of all custom enum types, for example: U ...