Navigation mesh is generated ignoring collision for ISM added by construction script

UE - AI - Navigation - Apr 15, 2025

When opening a map with ISM in place, NavOctree is not updated because the ISM bounds are assumed invalid and the geometry is not taken into account in the navmesh build.  The following log output i ...

Nanite TwoSidedSign is backwards

UE - Graphics Features - Nanite - Apr 10, 2025

The value of MaterialExpressionTwoSidedSign is flipped when calculating the Opacity Mask for Nanite meshes. This seems to be a regression in 5.5. ...

XR - Volumetric Clouds - VM Clouds appear overtop of meshes in the right-eye

UE - Graphics Features - Apr 10, 2025

When the user changes the Volumetric Render Target Mode, the Volumetric clouds in a scene will render in front of Static Meshes in the Right-Eye. ...

Child widgets do not maintain the Enhanced Input bindings from their parents

UE - Editor - UI Systems - Apr 9, 2025

When a widget blueprint is created with Enhanced Input bindings in the event graph, when it is subclassed those bindings will not work in the child. This is inconsistent with how Actors function, an ...

Iris - large fast arrays serialize multiple elements when only one is dirtied

UE - Networking - Iris - Apr 8, 2025

This seems to be a result of how the changemask is handled for fast arrays. Because the changemask is a fixed set of bits (defined by IrisFastArrayChangeMaskBits), a single bit can represent multipl ...

Incorrect volume bounds check in FTranslucentLightInjectionCollector::AddLightForInjection

UE - Graphics Features - Apr 8, 2025

The 'VolumeBounds' array in FTranslucentLightInjectionCollector::AddLightForInjection is accessed as a pointer instead of with 'VolumeCascadeIndex' and thus fails bounds checks for the outer volume. ...

Memory Leak When Raytracing Enabled with Specific Rendering Settings

UE - Graphics Features - Ray Tracing - Apr 8, 2025

When a shipping build is packaged using specific rendering settings a memory leak can be observed. The licensee has noted that this leak presents as a 10MB per hour increase in RAM usage. It has a ...

Crash in GPUMessage.cpp when resetting FSocket when RHI is NullRHI.

UE - Rendering Architecture - RHI - Apr 5, 2025

When tearing down a nanite project with the nullrhi active, there is a crash in the FeedbackManager destructor that causes any exit to be unclean. The teardown process causes a crash as the destruc ...