GPU System will kill existing particles if activate is called after it has be deactivated

UE - Niagara - Oct 22, 2020

Deactivating and then reactivating the same GPU system will cause existing particles to die. ...

Selecting other components after selecting a Spline Component's control point keeps the transform gizmo and functionality at the Spline Control point

UE - Editor - Workflow Systems - May 3, 2022

Selecting other components after selecting a Spline Component's control point keeps the transform gizmo and functionality at the Spline Control point Repro Rate: 4/4 Tested this in //UE4/Release-4 ...

Ensure condition failed: bPlayingBackwards ? (CurrentPosition <= PreviousPosition) : (CurrentPosition >= PreviousPosition)

UE - Anim - Sequencer - May 10, 2022

The problem is caused by the animation sequence playback position being set out of range from Sequencer. The call stack is :  UE4Editor-AnimGraphRuntime.dll!FAnimSequencerInstanceProxy::UpdateAnim ...

Mesh Paint mode's Texture Paint has obvious artifact with UV seams

UE - Rendering Architecture - Oct 8, 2024

Mesh Painting Texture Paint tool can miss some pixels along UV seams, even with "Enable Seam Painting" set to True. This appears to be because of the difference between rasterization and sampling. ...

LIVE: Multiplying an FQuat*FQuat via pass-by-value crashes editor on open

UE - Foundation - Core - Nov 5, 2014

If a function takes in an FQuat value and then multiplies it by an FQuat, the project will build properly but then crash when trying to launch the project in the editor. Example project available b ...

Alpha Channel Created when 'Accumulator Includes Alpha' is Disabled in MRQ

UE - Anim - Sequencer - MRQ - Apr 12, 2022

Occurs 3/3 times Alpha Channel Created when 'Accumulator Includes Alpha' is Disabled in MRQ issue discovered in LiveQA, and appears related to FORT-451157 Note: Whether 'Accumulator Includes Alpha ...

Clear Timer node does not stop a looping timer

UE - Gameplay - Feb 16, 2015

Setting a Clear Timer node does not stop the named function from firing. ...

"Play Rate" below 1 and "Force Fixed Frame Interval Playback" causes choppy renders

UE - Anim - Sequencer - Jul 12, 2016

"Play Rate" below 1 and "Force Fixed Frame Interval Playback" causes choppy renders. This was explained by Max on Answerhub to the user, but this seemed like something that should be bugged and loo ...

Mesh Painting sometimes fails to paint the closest face in the hovered area

Tools - Oct 10, 2016

Sometimes it's not catching certain polys as vertex paint targets. Looks like it happens when there's more than one layer of forward facing geometry over the highlighted area, and it just takes the ...

[CrashReport] UE4Editor_Engine!FSceneView::FSceneView() [sceneview.cpp:627]

UE - Editor - UI Systems - Slate - Apr 11, 2017

Opening UE4.14 using thecommand line "-forceenablecrashtracker," results in a red circle on the top right of the editor that when clicked provides a link to a 20 second video recorded from when you ...