Unreal Engine Issues

Enabling STATS causes RenderThread to wait for GPU

The licensee noticed that in Development builds, the Render thread times are suspiciously similar to GPU times, and the same thing happens when enabling FORCE_USE_STATS in Test configuration. The is ...

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

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

Invalid GUIDs on new material instance parameters cause overrides to break on base param rename

When a parameter value is assigned on a newly created material instance (constant or dynamic) using Set***ParameterValueInternal, the parameter’s ExpressionGUID is left invalid (0,0,0,0). Parameter ...

Precision issues with 16-bit Skin Cache shaders.

A licensee reported precision issues with position in the gpu skin cache shaders with 16-bit real types enabled. ...

Negatively scaled box collisions render back faces in Player Collision debug view

The player collision debug visualization for negatively scaled boxes is rendering the back faces, not the front faces. The debug primitives are rendered via the dynamic mesh builder. FDynamicMeshBui ...

Volumetric lightmap cache point becomes extreme bright if the light source is accidently at the exact(or almost) location of it

UMG Retainer Box renders incorrect colors with Color Vision Deficiency enabled

When using a Retainer Box in UMG with Color Vision Deficiency enabled, the content inside the Retainer Box is rendered with incorrect colors compared to the rest of the UI. This bug is present in UE ...

Copying a grouped MaterialInstanceParameterDetail property that has spaces on it's name does not enclose it in double quotes, and later pasting won't work as expected

Copying a grouped MaterialInstanceParameterDetail property that has spaces on it's name does not enclose it in double quotes, and later pasting won't work as expected. The licensee noticed this in a ...

Niagara Data Interface "Errors and Warning" section on Module Details not updating when error messages change

This is a regression: it worked correctly up to UE 5.5, but not in 5.6 or mainline latest. Possibly caused by CL 40093049. Class UNiagaraDataInterface provides virtual method GetFeedback(), which a ...

ACineCameraAttachMount's "Target Actor" constraint does not work with Spawnables or Replaceables in Sequencer

Constraints (UTickableConstraint) are usually created throuh the "Animation" tab available in the Editor's "Animation Mode". When created through that interface while Sequencer is open, the internal ...