Unreal Engine Issues
Unreal Engine Issues
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. ...
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 - 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 - 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. ...
With Ray Tracing Enabled And The RenderDoc Plugin Enabled Shadows Don't Render Correctly On Reflective Materials
UE - Graphics Features - Lumen - Jan 23, 2020When the RenderDoc plugin is installed with raytracing enabled shadows don't render correctly. Found in 4.24.1 CL#10757647 Reproduced in 4.23.1 CL#9631420, 4.25 Main CL#11087956 ...
Groom Assets do not cast shadows when the shadow casting light is close to the groom and virtual shadow maps are in use
UE - Graphics Features - Mar 19, 2024When a shadow casting light is closer to the groom than some proportional amount the groom is away from the shadow catcher, the groom's shadow will disappear. This only occurs using VSMs. Raytraced ...
Crash occurs loading a sublevel containing landscape with ray tracing enabled
UE - LD & Modeling - Terrain - Landscape - May 13, 2020In raytracing enabled, When loading a sublevel containing landscape with LoadStreamLevel function following error is shown. Assertion failed: Pair != nullptr [Link Removed] [Line: 584] Licensee re ...
Crash when a Deferred Decal (Translucent) base material has a Nanite Override (Masked Surface) Material and the mesh has Nanite + Ray Tracing enabled.
UE - Graphics Features - Ray Tracing - Aug 14, 2025A crash occurs when Nanite override material instance is used in a project with Ray tracing enabled where: 1 The Material assigned to the static mesh uses Deferred Decal / Translucent and the Nani ...