Graphical Artifacts in Editor with Macs using Certain AMD Graphics Cards

UE - Graphics Features - Sep 17, 2015

Users are reporting black and splotchy like graphical issues in their projects when working on a Mac and using an AMD graphics card. The user in the link provided mentions, "that UE 4.8.3 is withou ...

Create Session does not work in a packaged game from any project that has used C++

UE - Networking - Dec 28, 2015

After adding C++ to a content-only project, Create Session no longer works in a packaged game. The following warning appears in the log: LogScript:Warning: CreateSession - Invalid or uninitialized ...

Pre-UE5 serialized FVariant FVector data corruption when deserialized in UE5

UE - Framework - LWC - Jan 15, 2024

FVariant is a struct that implements a union of data types, including FVector. When assigning an FVariant an FVector value in engine versions UE 4.27 or earlier, the FVariant will deserialize incorr ...

Calling UBlueprintMapLibrary::GenericMap_Find with a non-existent key causes a memory leak

UE - Framework - Blueprint - Apr 15, 2025

When Calling UBlueprintMapLibrary::GenericMap_Find with a non-existent key, the function construct the default structure in-place on the given pointer without destroying the object. This behavior ca ...

Attempting to Open a Widget Blueprint With Animation and Timeline Panels Hidden Causes the Editor to Crash

UE - Editor - UI Systems - Nov 11, 2015

When you attempt to open a widget blueprint when you have hidden the animation and timeline panels, the editor will crash. There is a workaround: Window->Reset Layout will allow you to open the blu ...

Camera Movement is laggy while the mouse button is held down and ShowMouseCursor is enabled if there are AI moving

UE - Gameplay - Dec 15, 2015

Camera Movement is laggy while the mouse button is held down and ShowMouseCursor is enabled if there are AI moving. Stat Scene Rendering didn't show any jumps while moving the camera under these cir ...

[AI] Debug Render Scene Proxy hits ensure for registering a delegate twice during level streaming.

UE - AI - Debugging - Aug 31, 2022

Description from licensee: We're seeing an ensure get tripped up in FDebugRenderSceneProxy that says "DrawDelegate is already Registered!". Debugging the issue, we have confirmed that the DrawDeleg ...

ScreenPosition material node outputs upside down ViewportUV when launching on android

UE - Graphics Features - Aug 28, 2018

ScreenPosition UV upside down on mobile. From User: "I believe the editor mobile preview provides "correct" results, while the mobile device produces upside down results. I ran into this issue w ...

Direct Capsule Shadows with Point Lights also project shadow on opposite side and direction

UE - Graphics Features - Dec 14, 2016

When using a Direct Capsule Shadows on a skeletal mesh with a Stationary Point light, depending on the point lights placement, light source radius, and nearby surfaces will cast the shadow on the op ...

Sound Cues with Attenuation 'Override' Nodes break when Upgrading project to 4.11

UE - Audio - Apr 5, 2016

When upgrading a project to 4.11, Sound Cues placed in the level with the 'Attenuation' override node no longer playback as expected. This issue was a bit weird when testing because the user report ...