Unreal Engine Issues
Unreal Engine Issues
Translucent materials in the PostMotionBlur pass can cause a flickering viewport artefact when using TAA
UE - Rendering - Graphics Features - Feb 5, 2025There appears to be a bug relating to rendering multiple windows that can trigger under unknown circumstances. It has been reported on rectangle lights in the forums and on PostMotionBlur materials ...
Crash rendering image sequence if the Sub-Level with matinee is not loaded
Tools - Apr 15, 2016Crash rendering image sequence if the Sub-Level containing the matinee is not loaded. This seems to go away if the level is either set to "Always Loaded". Seems to be a result of people not switch ...
Crash when Previewing specific LODs within Static Mesh Editor at certain Screen Resolutions
Tools - Oct 27, 2016A crash occurs when attempting to preview specific LODs when the monitor resolution forces the menu to be expanded when selecting an LOD. This Jira was created from CrashReports submitted by the pu ...
FIXIF: Using the Merge Blueprints feature crashes the editor
UE - Gameplay - Blueprint - Feb 18, 2015Using the Merge Blueprints feature crashes the editor. This repro is for clicking between the error and warnings while merging, but the editor will generally crash if the Merge is finished or if an ...
When importing an FBX with Combine Meshes = False, one uasset will be created for the collection of assets.
Tools - Feb 4, 2016When importing a mesh, there is an option to Combine Meshes, which by default is checked. Unchecking this option will bring in the individually named parts contained in the FBX as unique objects in ...
Crash Importing Skeletal Mesh LODs with a lot of morph targets
OLD - Anim - May 18, 2016Crash Importing Skeletal Mesh LODs with a lot of morph targets Error message: Assertion failed: (Index >= 0) & (Index < ArrayNum) [Link Removed] [Line: 785] Array index out of bounds: 2 from an ar ...
Velocity Scene Texture Data Integrity Issues
UE - Graphics Features - Jan 8, 2026When a Post-Process Material uses the Scene Texture Material Expression, the following code is generated: ``` MaterialFloat2 Local0 = Parameters.TexCoords[0].xy; MaterialFloat2 Local1 = ClampSceneT ...
[CrashReport] UE4Editor_Engine!FRepLayout::InitFromObjectClass() [replayout.cpp:2211]
UE - Gameplay - Blueprint - Apr 19, 2016This Jira was created from CrashReports submitted by the public due to the high number of occurrences. Descriptions from users are provided below. Error message: Assertion failed: Property->Proper ...
[CrashReport] Mac crash - TArray<FDeferredMacEvent, FDefaultAllocator>::ResizeGrow
UE - Platform - Apple - Sep 14, 2017This is a somewhat common crash on Mac that has affected users since 4.16. Users have not provided any descriptions of their actions when the crash occurred. Callstack from Log [2017.09.08-05.17. ...
Crash retargetting AnimBP with "Allow remapping to existing assets" enabled
OLD - Anim - Aug 24, 20164.12 version of the crash: [Link Removed] Error message: Assertion failed: (Index >= 0) & (Index < ArrayNum) [Link Removed] [Line: 833] Array index out of bounds: 1 from an array of size 0 Sourc ...