Emissive Materials Change Colors Unexpectedly With Increased Values

UE - Graphics Features - Jan 24, 2017

When multiplying vector 3 (R,G,B) values by a scalar value of increasing quantity the emissive output will begin to change colors. The most unexpected is the blue color that will turn purple while t ...

SplineMeshComponent's collision will start to distort the longer the Spline becomes

UE - Gameplay - Nov 30, 2016

SplineMeshComponent's collision will start to distort the longer the Spline becomes This is a regession. It was working in 4.13.2-3172292 User Description: When drawing out a long spline mesh ( r ...

(BUG) Sequencer Root motion breaks down when using SwapRootWithActor, translation track and transform origin actor

UE - Anim - Anim in Engine - Jul 19, 2024

When "Sequencer.ThreadedEvaluation.AllocationThreshold 8" is initiated, characters in a level sequence that have “Swap Root Bone Actor” activated on their animation will begin to slide very fast acr ...

Multiplayer Shootout project sample is crashing on start

Docs - Samples - Apr 3, 2015

The project sample Multiplayer Shootout in the Learn tab is crashing on start up with 4.7.4 Crash does not occur on 4.8. Tested by Patrick.D on Main CL-2498147 Pass in 4.7.5 dev. - CKC 2503383 ...

Copying a call to a Custom Event or Function in another Blueprint and pasting it in the Blueprint the Custom Event or Function comes lives in will cause a compile warning or failure

UE - Gameplay - Blueprint - Apr 17, 2015

Copying a call to a Custom Event or Function in another Blueprint and pasting it in the Blueprint the Custom Event or Function comes lives in will cause a compile warning or failure. In 4.7.5 it giv ...

Landscape Splines in Partially Loaded World Partition Levels Can Cause Nanite Landscape Invalidation

UE - Graphics Tools - Terrain - Nov 7, 2025

Certain placements of landscape splines in world partition levels can cause Nanite landscape proxies to invalidate, and switch back to their non-nanite version. This happens when specific regions of ...

ChaosWheeledVehicleMovementComponent is breaking the const CDO contract and changes to the instances are being applied to the CDO

UE - Simulation - Gameplay - Apr 28, 2025

As described by the licensee, the const CDO contract is being broken on ChaosWheeledVehicleMovementComponent. The issue the licensee is facing is that by spawning cars with different configurations, ...

Paper2D: Editor hangs when assigning Sprite Atlas Group to Sprite

UE - Gameplay - Paper2D - Dec 16, 2025

In UE 5.3 and later, assigning a Sprite Atlas Group to a UPaperSprite asset can cause the editor to hang and eventually crash. This behavior has been reproduced in 5.3, 5.6, and a recent UE5-main so ...

Destructible Mesh spawned before static mesh with World or Asset support is not supported

UE - Simulation - Physics - Destruction - Apr 27, 2015

When using World Support or Asset Defined Support on a Destructible mesh that is spawned in, if the static world geometry is spawned in after the DM it will not be supported. However, if the static ...

Play Media Player Node Causes Blueprint Functions to be Uncallable

UE - Gameplay - Blueprint - Feb 23, 2016

This only occurs in standalone or a packaged game Having a Play Media Player node in a blueprint causes all of that blueprint's functions to become uncallable. Found in 4.11 Preview 5. Reproduced ...