Raytraced lights with Source Length > 0 behave incorrectly with Megalights

UE - Graphics Features - Ray Tracing - Mar 26, 2025

When Megalights is enabled, light can leak into areas that should be occluded for lights with smallish (5.0) source length and source size. [Image Removed][Image Removed] This was taken with r.Ray ...

FRayTracingGeometryManager::Tick() called twice during a single frame

UE - Graphics Features - Ray Tracing - Mar 5, 2025

UDN licensee Prophecy Games has encountered an issue in which the RaytracingGeometry::Tick() function is called twice during a single frame. This causes an assert to trigger, which blocks them from ...

Soft Raytracing Shadows are flickering

UE - Graphics Features - Ray Tracing - Feb 18, 2025

[Image Removed][Link Removed] ...

The Starter Contents SM_Statue exists in a bad state, leading to crashes when trying to open levels where it is referenced

UE - Graphics Features - Ray Tracing - Feb 18, 2025

The SM_Statue exists in a bad state leading to a crash when it is loaded or anything that references it is loaded, e.g. Minimal Default level in the Starter Content. It can be deleted as a temporar ...

Editor/Game Ensure hit with RayTracing enabled on AMD GPU

UE - Graphics Features - Ray Tracing - Feb 4, 2025

A Static Mesh asset will trigger an ensure when generating building the ray tracing acceleration structure on AMD GPUs. ...

Spline mesh crashing in FRayTracingDynamicGeometryCollection::AddDynamicMeshBatchForGeometryUpdate

UE - Graphics Features - Ray Tracing - Jan 31, 2025

A crash occurs when using ray tracing with spline meshes preceded by the following ensure : Ensure condition failed: NumCPUVertices <= VertexBufferNumElements  File: Engine\Source\Runtime\Renderer\ ...

Lumen ignores Landscape Holes (Landscape Visibility) when Hardware Ray Tracing is enabled and Ray Lighting Mode is set to Surface Cache

UE - Graphics Features - Ray Tracing - Jan 31, 2025

Context Lumen is the default global illumination and reflections system. Lumen renders diffuse interreflection with infinite bounces and indirect specular reflections in large, detailed environments ...

GPU Crash from invalid SRV in CreateShaderResourceView due to integer underflow

UE - Graphics Features - Ray Tracing - Jan 15, 2025

The GPU crashes after the ray tracing geometry builder attempts to create a shader resource view with an invalid offset. ...

GPU Crash from invalid SRV in CreateShaderResourceView due to integer underflow

UE - Graphics Features - Ray Tracing - Jan 13, 2025

The GPU crashes after the ray tracing geometry builder attempts to create a shader resource view with an invalid offset. ...

Ray traced shadow appears for translucent material after LOD change

UE - Graphics Features - Ray Tracing - Aug 21, 2024

When ray-traced shadows are enabled, the shadow for a completely translucent mesh appears when the LOD changes based on distance. ...