Building Nanite on a Landscape with Visibility Mask multiple times gives an Assert

UE - Graphics Tools - Terrain - Landscape - Aug 28, 2023

Repro Rate 15/25 Regression set to Yes as this was not found on //UE5/Release-5.2 CL 26001984 Binary Building Nanite with a Landscape that has a material including Landscape Visibility Mask still ...

Foliage LODs do not appear to use the base LODs lightmap any longer

UE - World Creation - Worldbuilding Tools - Foliage - Dec 16, 2016

LODs used with the Foliage Tool are no longer being shadowed accordingly with their baked lighting from their base LOD. Originally they would stay consistently lit, where as now the lower LOD transi ...

Stationary/Movable Lights render based on distance from World Origin in Orthographic Camera View

UE - Graphics Features - May 20, 2016

When using the Orthographic Camera view (such as that used with the Paper2D Template) any lights that are distant from the world origin will start to fade out as if they are being culled. The distan ...

[CrashReport] FSlateRHIRenderer::ConditionalResizeViewport()

Tools - Jul 27, 2017

This is a common crash occurring on Windows and Mac in 4.15 and 4.16 (two different callstacks with close similarities). The callstack is also similar to [Link Removed] and may be related. User D ...

UClass::SparseClassDataStruct null at editor-time for child blueprints until compile

UE - Framework - Blueprint - May 29, 2024

Child blueprints of a blueprint of a native actor class with sparse data can have an incorrectly null SparseClassDataStruct value, and thus fail to initialzie their SparseClassData. This affects edi ...

VR Preview crash when shadow quality is set to low

UE - Platform - XR - Dec 5, 2024

[/Script/Engine.RendererSettings] r.Tonemapper.Sharpen=2 r.TemporalAA.Upsampling=False r.DefaultFeature.AutoExposure.ExtendDefaultLuminanceRange=True r.LightPropagationVolume=0 r.ReflectionCaptureRe ...

Substrate Single Layer Water material fails to compile in blendable Gbuffer mode when using the Single Layer Water BSDF node

UE - Graphics Tools - Terrain - Water - Jun 16, 2026

When using Substrate in Blendable GBuffer mode, a material with the single layer water BSDF node produces a shader compiler error : MaterialEditorStats: Error: [SM6] Shader debug info dumped to: "\ ...

The AABBTree spatial acceleration structure goes off-sync when physics substepping is enabled in a "low" framerate environment.

UE - Runtime - Simulation - Mar 15, 2024

When you enable the physics substepping, if you run the console command p.Chaos.Solver.DebugDrawSpatialAccelerationStructure 1, you can see how does not follow the physical object. The user that rep ...

Empty Shot Track Breaks Camera Component tracks when using Camera Cut Track

UE - Anim - Sequencer - Aug 18, 2016

Empty Shot Track Breaks Camera Component tracks when using Camera Cut Track ...

Assertion failed: (Index >= 0) & (Index < ArrayNum) when importing large Alembic file

UE - Editor - Content Pipeline - Datasmith - Importer - May 3, 2022

Regression testing done on //UE4/Release-4.27.2 CL-18427296 and this issue did occur. [Link Removed] [Link Removed] Below is snips of customers description and proposed workaround:Importing alembi ...