Unreal Engine Issues
Unreal Engine Issues
Spline mesh crashing in FRayTracingDynamicGeometryCollection::AddDynamicMeshBatchForGeometryUpdate
UE - Rendering - Graphics Features - Ray Tracing - Jan 31, 2025A crash occurs when using ray tracing with spline meshes preceded by the following ensure : Ensure condition failed: NumCPUVertices <= VertexBufferNumElements File: Engine\Source\Runtime\Renderer\ ...
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, 2026When 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: "\ ...
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 ...
Opening Sprite assets or Paper Flipbook crashes the engine in 5.3
UE - Gameplay - Paper2D - Apr 16, 2024Licensee was not able to open any Sprite asset file in 5.3 without it causing a crash. They were able to avoid this by disabling raytracing in the project. ...
FNiagaraRendererMeshes::GetDynamicRayTracingInstances(...) corrupting GPUScene when rendering multiple views
UE - Rendering - Graphics Features - Ray Tracing - May 20, 2026When rendering a game in splitscreen using Lumen HWRT, Nanite and a large number of Niagara Mesh Particles 1mil+, various meshes and actors will stop rendering. Setting r.RayTracing.Geometry.Niagar ...
Editor compile failure in UnrealEngineHTML5 -- unsafe use of type 'bool'
UE - Platform - Mobile - Dec 4, 2019Severity Code Description Project File Line Error ...
Certain materials are overly bright with Ray Traced Global Illumination denoiser
UE - Graphics Features - Lumen - Mar 14, 2019Ray Traced Global Illumination is causing some materials to glow extremely bright Disabling r.raytracing.globalillumination.denoiser fixes the issue In 4.22 preview 5 binary (5365847) the result i ...
Incorrect Lumen Scene direct lighting when objects behind masked landscape
UE - Rendering - Graphics Features - Lumen - Oct 5, 2025When objects are placed behind or beneath a masked landscape and r.Lumen.HardwareRayTracing.SurfaceCacheAlphaMasking is enabled, the direct light evaluation is incorrect. There are two workarounds, ...
MRQ - No Rayrtaced Shadows casted from Groom Caches with only 1 Spatial Sample
UE - Rendering - Graphics Features - May 28, 2025A groom cache will not cast a raytraced shadow with only 1 spatial sample. It does not matter how many temporal samples you have. ...
Indirect Capsule Shadows showing up on Unlit Characters
UE - Graphics Features - May 5, 2023For this to be observed, Allow Static Lighting must be true in project settings. This appears to be coming from an AO pass and from a Raytraced Indirect Capsule Shadows. ...