Mover MoveDirectionIntent can be 0 due to interpolation

UE - Gameplay - Player Movement - Apr 22, 2025

If two states have MoveDirectionIntent vectors that are opposite to each other, interpolating between these states can result in MoveDirectionIntent being 0. This may cause issues for animation blue ...

r.Shaders.Optimize=0 crashes when compiling a UI material

UE - Rendering Architecture - Materials - Sep 2, 2024

[2024.08.30-22.12.22:384][ 73]LogWindows: Error: appError called: Assertion failed: CurrentGPUVirtualAddress != 0 [Link Removed] [Line: 659] Disabling shader optimisation can crash the editor when ...

Foot Placement: Division by 0

UE - Anim - Gameplay - Jan 31, 2025

static FVector PointDirectionPlaneIntersection(const FVector Point, const FVector Direction, const FPlane Plane) { return Point + Direction * ((Plane.W - (Point | Plane)) / (Direction | Plane)) ...

Biquad Filter is incorrect when bandpass is 1.0

UE - Audio - Signal Processing - Aug 20, 2024

The bandwidth on the biquad loepass filter is cutting frequencies well below 20kHz when the bandwidth is 1.0. Slack convo: [Link Removed] Visualization:[Image Removed] ...

LODs with screen size 0 in legacy assets are incorrectly converted to 1 on load

UE - Graphics Features - Sep 11, 2025

When loading a mesh asset (static or skeletal) created in an old version of Unreal (e.g. 4.10), any LOD whose LOD screen size was originally set to 0, is converted to 1. This causes LODs that would ...

Changing preview mesh appears to affect initial transforms of all control rigs in level viewport

UE - Anim - Rigging - Control Rig - Apr 16, 2024

It seems that switching the preview mesh in the control rig editor is affecting the initial transforms in the hiearchies of related control rigs in the level viewport.  This seems to be due to the c ...

Level Instances appear at the origin on Linux cooks

UE - World Creation - Worldbuilding Tools - Level Instances - Aug 14, 2024

Level Instances are spawned in the origin (0,0,0) after making a packaged build in Linux ...

ensure(PinHelpers::UnresolvedPins.Num() == 0); fails after undoing in the editor

UE - Framework - Blueprint Editor - Sep 6, 2025

The underlying cause is some edge case involving a math expression node, which does some perhaps naive things with a contained graph. ...

SkyLight Leaking does not affect reflections when the SkyLight is static but static lighting is disallowed

UE - Graphics Features - Sep 10, 2025

Reflections do not receive SkyLight leakage contribution from a static SkyLight when static lighting is disallowed. This is caused by the function UpdateSkyIrradianceGpuBuffer checking if the SkyLig ...

Insufficient precision of Decode71 function

UE - Rendering Architecture - Shaders - Jun 5, 2025

Encode71 and Decode71 in DeferredShadingCommon.ush are functions that convert 8-bit values ​​to 7-bit values ​​and mask values, and licensees have reported that the accuracy is insufficient when usi ...