Unreal Engine Issues
Unreal Engine Issues
Patterns On Landscape Spline Normals
UE - Graphics Tools - Terrain - Oct 31, 2025On higher-density Landscapes, Landscape Splines can lead to patterned artifacts in the geometry normals. Also tested on //UE/Release-5.6, CL:45232827 ...
LWCLength precision issues
UE - Rendering - Features - Nov 18, 2025Large World Coordinates tile-offset position data can result in artifacts far from the world origin, when using it as input for mathematical distance field generation. This can be mitigated by demot ...
Material LocalPosition node does not work correctly with Nanite Skinned meshes
UE - Rendering - Features - Dec 1, 2025Nanite Skinned Meshes don't receive the correct Local Position in some shadow passes. This depends on the clipmap level, and is not related to VSM caching. Unreal Engine 5.6 shows the same issue, b ...
Out-of-Bounds Access During Partial Updates of ISMC Per-Instance Custom Data
UE - Rendering - Features - Jan 6, 2026When using instance custom data values, removing an instance and changing the number of custom data floats in sequence can cause an array-out-of-bounds crash. The underlying arrays are not resized ...
Temporal blur artifacts on Geometry Cache Components in Blueprint actor
UE - Editor - Open File Formats - Alembic - Jan 9, 2026When a Geometry Collection is in a Blueprint, attached to other components, it can render incorrect motion vectors at some angles. In the test project, any angle that is not a multiple of 45 will re ...
Lumen Global Distance Field Trace Leaking due to Surface Cache Sampling
UE - Rendering - Features - Jan 12, 2026At specific distances from a thin wall, surfaces inside of a sealed chamber can receive indirect lighting from outside, leaking light into the chamber. This appears to be due to how SWRT handles sa ...
HISM flickering when any character is visible
UE - Rendering - RHI - Jan 12, 2026On an NVIDIA GPU, Instanced Static Meshes can flicker when a Groom card or mesh LOD is visible. This appears related to an issue rendering the ISM into the Scene Depth. At the end of the Prepass, t ...
"Move to Level" of Landscape Tool leads component scale mismatch
UE - Graphics Tools - Terrain - Landscape - Feb 12, 2026In UE 5.7.2, when moving a Landscape Component to a sub-level using Landscape Mode > Manage > Move to Level, the proxy transform is not synchronized with the root Landscape when the KeepWorldTransfo ...
Skeletal mesh reimport via legacy import creates duplicate Mesh sockets
UE - Editor - Open File Formats - Import and Export - Feb 25, 2026Reimporting a Skeletal Mesh via legacy import duplicates mesh sockets. The issue does not reproduce when using the Interchange pipeline. ...
STAT_StaticMeshTotalMemory increases after repeated loading and unloading of a level containing Nanite static meshes
UE - Rendering - Features - Nanite - Feb 26, 2026The issue appears to be caused by a mismatch in the value returned by GetResourceSizeBytes(EResourceSizeMode::Exclusive) between InitResources() and ReleaseResources(). At InitResources(), the repo ...