Unreal Engine Issues
Unreal Engine Issues
Rect light artifacts from NaN pixels on surfaces that are coplanar with light position
UE - Graphics Features - May 10, 2024Rect lights cause artifacts (nan pixels) on pixels of surfaces that are coplanar with light position. In RectLight.ush, in RectIrradianceLambert, at line 106, c30 is -1, so rsqrt(0) causes a nan to ...
Virtual Texture Collection Indexing Not Working
UE - Rendering Architecture - RHI - Oct 30, 2025Textures at an index, other than 0, cannot be sampled from a Virtual Texture Collection in a material. When using the Texture Collection and Texture Object From Collection material nodes, with a Vir ...
Crash opening blueprint when a node class has been removed (e.g., anim blueprint with Ragdoll node with Immediate Mode plugin disabled)
UE - Gameplay - Blueprint Editor - Jan 26, 2017Crash occurs when the user attempts to open an anim blueprint containing the Ragdoll node, when Immediate Physics is disabled. ...
NVIDIA 5080 GPU Crash when launching City Sample with DX12
UE - Graphics Features - Lumen - Apr 16, 2025UPDATE This issue no longer reproduces on driver versions 580.88 and higher. City Sample game crashes immediately upon opening with a NVIDIA 5080 with the latest drivers as well as some previous dr ...
Setting "Is Enabled" via the animation timeline in UMG does not appear to work at runtime
UE - Editor - UI Systems - Jun 10, 2016Setting "Is Enabled" via the animation timeline in UMG does not appear to work at runtime ...
[CrashReport] CastChecked<UAnimBlueprint,UBlueprint>()
OLD - Anim - Jul 14, 2017This is a common crash affecting users in 4.16. Users have not provided additional information. Source context not available ...
Scroll Bar does not Stay "Anchored" to Bottom While Data Generates in Window
Tools - Jun 6, 2016The scrollbar no longer remains anchored to the bottom of the Output Log while more lines are propagated during the packaging process/ Regression: this does not occur in previous versions of the En ...
Cannot move instances of a hierarchical static mesh component in the blueprint editor viewport
UE - Gameplay - Components - Apr 12, 2016Can move individual mesh instances of a regular instanced mesh component in the blueprint editor, but not hierarchical ones. Originally reported as a pull request in [Link Removed], but we rejected ...
Changing LODBias on landscape sections causes grass type placement issues
UE - LD & Modeling - Terrain - Landscape - Jun 6, 2018Changing LODBias on landscape sections causes a grass type placement issues. The grass will be floating and rotated incorrectly. Found in 4.18 CL# 3832480, 4.19 CL# 4033788, 4.20 Preview 1 CL# 4 ...
Crash when trying to "Update Mesh Section" on any procedural mesh just after "Clear Mesh Section" and "Create Mesh Section" for different vertices and triangles.
OLD - Anim - Jun 15, 2018the editor Crashes when trying to "Update Mesh Section" on any procedural mesh just after "Clear Mesh Section" and "Create Mesh Section" for different vertices and triangles. Found in 4.19 CL# 4033 ...