VulkanStagingBuffers stat continually to grows.

UE - Platform - Mobile - Oct 24, 2025

On Android phones, VulkanStagingBuffers continually grows when the scene is static. From looking at FStagingManager, it appears the VulkanStagingBuffers atat is only updated on buffer acquisition, ...

Custom Depth range is different than Pixel Depth range

UE - Rendering Architecture - Shaders - Sep 25, 2025

Shaders that compare custom depth and pixel depth get wrong output values because the ranges are different. This error is most noticeable over large distances. The difference in ranges is due to t ...

Ray tracing scene doesn't reflect WPO with instance custom data

UE - Graphics Features - Ray Tracing - Sep 19, 2025

When custom instance data is used to calculate WPO in a Material and applied to an ISM the WPO value in the Lumen scene (ray tracing scene) is different than the visible scene resulting in incorrect ...

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

UE - Editor - Content Pipeline - 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 ...

Incorrect resolution used because SetProcessDpiAware() is not called when bAllowHighDPIInGameMode=False

UE - Rendering Architecture - Aug 8, 2025

The incorrect resolution is used on computers with 4k monitors that use DPI scaling (default 150%) because the default for UE projects is bAllowHighDPIInGameMode=False which results in SetProcessDp ...

GPU Crash from out of memory read/writes in Lumen when using non-power-of-2 TracingOctahedronResolution

UE - Graphics Features - Lumen - Aug 6, 2025

When the r.Lumen.ScreenProbeGather.TracingOctahedronResolution is not a power of 2 or LumenFinalGatherQuality in a Post Processing Volume is set to a value such that the TracingOctahedronResolution ...

Sequencer - When a subsection has negative play rate, any nested sub-subsections fail to evaluate

UE - Anim - Sequencer - Jul 3, 2025

Consider a sequence hierarchy with more than two layers. If the top-level sequence uses a negative timescale on a sub-sequence, the contents inside it animate as expected, but any nested sub-sequenc ...

Sphere Mask ArgInvHardness missing multiplication

UE - Rendering Architecture - Materials - Jun 27, 2025

Hi Epic, In MaterialExpressions.cpp UMaterialExpressionSphereMask::Compile(), hardness is not calculated the same way in both <if> conditions. One is missing a multiplication by 0.01f. Specificall ...

Instanced Static Meshes ignore max World Position Offset Displacement for bounds after UpdateInstanceTransform is called

UE - Graphics Features - Jun 18, 2025

When an Instanced Static Mesh Component (ISMC) uses a material with a non-zero Max World Position Offset Displacement, the bounds are correctly expanded at initialization. However, after calling Upd ...