Unreal Engine Issues
Unreal Engine Issues
New VR-Basic level triggers Metal validation layer assertion
UE - Platform - Apple - Mar 16, 2020This was discovered externally and reported on UDN here: https://udn.unrealengine.com/questions/563268/mac-editor-crash-when-disable-ambient-occlusion.html ...
Structs cause packaging to fail when Blueprint Nativization Method is set to "Inclusive"
UE - Gameplay - Blueprint - Apr 26, 2017Structs cause packaging to fail when Blueprint Nativization Method is set to "Inclusive" Note: Appears to be a regression (worked in 4.15.1) Error example: UATHelper: Packaging (Windows (64-bit)) ...
Project does not cook with actors containing ModularSynth component
UE - Audio - Sep 11, 2017A project does not cook with actors containing ModularSynth component. The error is a follows UATHelper: Packaging (Windows (64-bit)): Cook: LogWindows: Error: begin: stack for UAT UATHelper: Pack ...
CLONE - Project does not cook with actors containing ModularSynth component
UE - Audio - Sep 13, 2017A project does not cook with actors containing ModularSynth component. The error is a follows UATHelper: Packaging (Windows (64-bit)): Cook: LogWindows: Error: begin: stack for UAT UATHelper: Pack ...
MRQ render with a slow output format drives Niagara GPU tick flush into its dummy-view path, causing an access violation in SetShaderParameters
UE - Rendering - Architecture - Niagara - Aug 18, 2026Sorry for the AI ticket, but it did a better job than I could: Rendering a level sequence through Movie Render Queue crashes the editor with an EXCEPTION_ACCESS_VIOLATION when the scene contains a N ...
Crash in FMovieSceneNumericVariant::Set when loading a Level Sequence with Custom Time Warp on Android
UE - ACT Character - Sequencer - Aug 14, 2026On Android, loading a Level Sequence fatals in the async loading thread: Assertion failed: (NewValue & ~PAYLOAD_Bits) == 0 MovieSceneNumericVariant.cpp:133 Unable to store a pointer outside of a ...
Lighting behavior is unreliable for translucent lit materials, results are inconsistent depending on the editor camera's FOV and the editor viewport's width/height/aspect
UE - Rendering - Architecture - Oct 27, 2024When working on the level editor viewport or testing on PIE, the visual appearance of additive/translucent lit materials changes significantly (and abruptly) when varying the camera FOV or the viewp ...
Connecting GetSequenceBinding node to LevelSequence including Spawnable Actor etc. will result in error
UE - Gameplay - Blueprint Editor - Feb 22, 2018[Link Removed] ・Open attached project ・Open NewMap ・Confirm that an error appears on the console ・When creating a Windows (64-Bit) package in this state, the same error occurs ...
Blackboard decorator node does not abort lower-priority nodes
UE - AI - Feb 16, 2026When a branch of a selector is deactivated, all auxiliary nodes and observer delegates are removed. If the branch is reactivated soon and the CurrentActiveNode remains unchanged, the behavior tree l ...
Bug in StringTemplate.cpp related to modulo operator in MaterialTemplate.ush (code fix provided)
UE - Rendering - Architecture - Materials - Jun 25, 2024Shader Template files like MaterialTemplate.ush do not submit previous chunks when encountering a `%` character, unless that `%` character is `%s` or `% {...} `. Because the error is happening ...