DrawDebug elements on screen affect aspect ratio letterboxing

UE - Rendering - Architecture - Nov 1, 2023

During gameplay when the view target camera's aspect ratio is not exactly the viewport's aspect ratio, the presence of rendered debug draw elements (DrawDebugArrow, etc) makes the viewport's rendere ...

Copy Actors out of play mode ( 5.3.1 )

UE - Editor - Dec 22, 2023

From UDN case #00645621: Is it possible that this function has been deactivated? In 5.03 I can copy objects from the game mode. ...

Split Struct Pin on a Function output will return a compiler error

UE - Gameplay - Blueprint - Jan 13, 2015

Split Struct Pin on a Function output will return a compiler error: Error Pin New Param 1 X named NewParam1_X doesn't match any parameters of function NewFunction_0 Error Pin New Param 1 Z name ...

Incorrect shading for SubSurface profile in the Blueprint Viewport.

UE - Graphics Features - Dec 30, 2016

The Subsurface shading looks incorrect in the Blueprint Viewport window. Adjusting the cvar for r.sss.checkerboard from the default value of 2 to 1 looks more correct and a value of 0 switches back ...

UMG Designer preview: Incorrect resolution on Samsung s8 and s9

UE - Editor - UI Systems - Jul 30, 2018

"By default, the device profile for android_high (which is used by phones such as the galaxy s8 and s9) gives a scale factor of 1.0 resulting in 1280x720. When choosing a ~2:1 device such as the gal ...

Editor Crashes when importing some FBXs with multiple Material IDs in 4.14.2

UE - Editor - Content Pipeline - Import and Export - Jan 5, 2017

This is a regression in behavior between 4.14.1 and 4.14.2! The editor will crash when importing FBX meshes that have multiple material ID assignments. If it's a single material ID it will import w ...

Particles Do Not Obey Lighting Channels

UE - Niagara - Apr 17, 2018

Particle systems ignore lighting channels - no matter what channel a light is on (even if no channels are selected), it will affect lit particles. Changing lighting channels on the particle itself h ...

Float Curve evaluation may yield completely wrong results due to floating-point precision issue

UE - Runtime - Animation - Oct 31, 2024

Note: This is possibly related to [Link Removed] Backlogged . For some inputs, function UE::Curves::WeightedEvalForTwoKeys( ...

Blurry RVTs after camera jump

UE - Rendering - Features - Aug 7, 2025

When using Runtime Virtual Textures (RVT) on landscape in UE 5.5+, nearby tiles may remain blurry (low-resolution mips) after launching PIE or making large camera jumps (e.g. via bookmarks or viewpo ...

The Height of a Jump When Holding the Jump Button is Dependent on Framerate

UE - Gameplay - Player Movement - Nov 20, 2015

Setting the Max Jump Hold Time variable to 1 second, and then holding the jump button produces different results depending on the framerate. In this case, the normal jump is at a specific height, bu ...