UV Flipping Mode Causes Stretching of Particles

UE - Niagara - Nov 17, 2017

If "UVFlipping Mode" under Rendering on the Required node of an emitter is set to anything other than "None," the particles can become stretched and distorted. As a workaround, I have discovered th ...

Unable to play replays with custom GameNetworkProtocolVersion set at runtime

UE - Networking - Sep 20, 2023

It seems that when comparing the custom versions for a replay (in the "operator<<" defined in ReplayTypes.cpp), the value retrieved from the FCurrentCustomVersions is not the value set at runtime, b ...

Crash enabling Stochastic Rect Light with Ray Tracing

UE - Graphics Features - Lumen - Oct 13, 2020

Enabling Stochastic Rect Lights with Ray Tracing causes the project to crash. Reported and tested in version 4.26.0(CL 14419252). Tested and not found in version 4.25.3(CL 13942748).  ...

Non-Uniform Mobile Content Scale Values Render Black Screen when Launching to Mobile Device

UE - Platform - Mobile - Mar 3, 2015

When attempting to set the configuration for mobile devices within the Engine/Config/DefaultDeviceProfiles.ini, any value that is non-uniform like 1.2 or 1.6 will render a black screen after deployi ...

GPU Particle Collision changes based on Normal Intensity on Colliding Surface

UE - Graphics Features - Jun 18, 2015

Increasing the intensity of a Normal Texture on a colliding surface will cause the collision of GPU particles to behave strangely, looks to be falling through floor, when you are using a Constant Ac ...

Source control reports errors rather than warnings regarding line endings, causing false negative failure of commandlets.

UE - Editor - UI Systems - Localization - Jun 16, 2015

Second issue arises when I have already created localization related files when not connected to source control, so they are not marked to add. Gather Text commandlet log has theese lines in it: [2 ...

Actor instance FComponentReference to other actor instance gets nulled on other actor recompile

UE - Gameplay - Blueprint Compiler - May 21, 2024

An editable FComponentReference property on an actor instance can be used to reference another actor's component in the scene. In 4.27 and earlier versions these references were retained when the ot ...

Extremely far out zoom creates jagged lines where meshes overlap.

UE - Graphics Features - Jul 17, 2015

I created a very large static mesh and then put a basic floor underneath it withe the bottom of the mesh overlapping the floor. I then created a camera 250,000 cm out from the mesh and zoomed in usi ...

[CrashReport] UE4Editor_Persona!FReferenceSkeleton::FindBoneIndex() [referenceskeleton.h:252]

OLD - Anim - Jul 20, 2017

This is a common crash affecting users in 4.16, and has occurred since at least 4.14, affecting more than 200 unique users. Unfortunately none of them have provided any additional information. Sou ...

Some Twinmotion library assets do not render in Path Tracer in files with a large number of assets

TM - Rendering - Apr 17, 2025

Reported in SF [Link Removed] In scenes containing large numbers of certain Twinmotion assets, when activating Path Tracer, some of the assets will not render. The assets will render normally in St ...