Sphere Mask ArgInvHardness missing multiplication

UE - Rendering - Architecture - Materials - Jun 27, 2025

Hi Epic, In MaterialExpressions.cpp UMaterialExpressionSphereMask::Compile(), hardness is not calculated the same way in both <if> conditions. One is missing a multiplication by 0.01f. Specificall ...

360 videos with precipitation will get darker at times

TM - Rendering - Sep 19, 2025

Reported in SF [Link Removed] When exporting 360 videos with precipitation, there may be a noticeable darkening effect in the exported render that fades in and out. This effect is not present in th ...

Fbx importer can import valid under 30Hz anim at 30Hz

Tools - Jul 17, 2017

The samplerate of a track was compute with the following formula Equation 1: number of Key / animation Time This formula work only if we have animation keys that are time equidistant. example of ...

Scalar Parameter versus Constant placed in Alpha of LERP produces inconsistent results in Blendable

UE - Graphics Features - Jun 8, 2015

When placing a Scalar Parameter into the Alpha position of a LERP you will not get the same results as placing a Constant Value when used in a Post Process Material. Constant Value of 0: [Image Rem ...

Motion Controller Axis input values over scale in increments of 2

UE - Platform - XR - Jan 8, 2020

The Axis input values for SteamVR motion controllers will increase exponentially by 2 from the moment the editor starts and every time the user enters VR Mode or does a Launch On (eg. Entering VR Mo ...

World Position Offset causing Cracks in Meshes on certain iOS Devices

UE - Platform - Mobile - May 24, 2017

When using World Position Offset and pushing verts of a mesh, cracks appear on the surface using WPO when deployed to an certain iOS devices. I used the Mobile Previewer to compare results to how t ...

Kinematic in Physics Asset Overrides Bone Scale of Skeletal Meshes

UE - Simulation - Physics - Oct 7, 2020

In a character's Physics Asset, a bone that is set to Kinematic and its children will have a scale of 1 overriding the Skeletal Mesh's Scale Transform settings. When the root of the body is changed ...

Rendered panoramas using Lumen may be overexposed

TM - Rendering - Sep 30, 2025

Reported in SF [Link Removed] Lumen Panorama renders in 2025.2 may appear overexposed compared to the viewport, or when comparing the same render produced in 2025.1.1 This only appears to occur wi ...

Interaction between sublevels and LevelSequences can break actors attachments hierarchy of the sublevel.

UE - World Creation - Worldbuilding Tools - Aug 6, 2025

Having a LevelSequence opened and unhiding a sublevel can break the attachment hierarchy of the actors that are inside the sublevel. This also affects to the sublevel asset itself. ...

Slight delay when switching between UMG buttons on Mac

UE - Editor - UI Systems - Dec 30, 2014

There is a slight delay when clicking between two different UMG buttons on Mac. Tested on OSX 10.10.1. There also appears to be a flicker on the Menu Bar. ...