Unreal Engine Issues
Unreal Engine Issues
Sequence with restore state set is causing a "Fatal world leaks detected" crash
UE - Anim - Sequencer - May 14, 2025We recently had a few occurrences of crashes caused by a "Fatal world leaks detected" error when unloading a level (in a packaged game and in editor). I tracked down what was keeping a references t ...
Levels lose folder hierarchy in Levels window on streaming method change
Tools - Mar 19, 2019In the Level Window, Sub Levels which are nested inside of a folder will lose their hierarchy upon changing their streaming methods. ...
Some texture files cannot be exported from the editor
Tools - Feb 4, 2015There are instances where some texture files cannot be exported from the editor. In this older post a user had reported this with the file T_Sky_Blue from the engine folder. Only this file has been ...
[Review Tool] The editor crashes while attempting to load a modified Blueprint that uses Interface for review.
UE - Framework - Diff Merge Tool - Jul 16, 2025The crash is due to previous Rename operation, that reset a preallocated array which later FAsyncPackage2::ExecuteDeferredPostLoadLinkerLoadPackageExports tries to use. Before loading change list ...
Invisible child components appear for one frame on scene capture 2D windows if another component is attached.
UE - Gameplay - Oct 1, 2015Invisible child components appear for one frame on scene capture 2D windows if another component is attached. ...
CapsuleComponent with CCD on will push and pull any simulated physics objects when close but not in contact with the capsule
UE - Gameplay - Jul 21, 2015When using a capsule component for the character with CCD enabled there can be a force that pulls or pushes simulated meshes that are never touched by the capsule. Demonstration video attached. As ...
Custom Node plugged into World Displacement cannot convert from FMaterialTessellationParameter to FMaterialPixelParameter
UE - Graphics Features - Nov 30, 2015Custom Nodes plugged into World Displacement are yielding:Error [SM5] error X3017: 'CustomExpression1': cannot implicitly convert from 'struct FMaterialTessellationParameters' to 'struct FMaterialP ...
Physic Constraint movement is quadratic where previously it was spherical
UE - Simulation - Core - Apr 6, 2022Physic Constraint movement is quadratic where previously it was spherical. ...
AreaFlags Empty During First PIE Session After Hot Reloading
UE - AI - Dec 12, 2016AreaID always seems to be empty during the first PIE session after hot-reloading. Only able to test in Dev-Framework CL# 3221683 due to the licensee's project being created in 4.15 and not being b ...
ObjectPivotPoint does not work with instanced Nanite meshes
UE - Rendering - Architecture - Materials - Nov 17, 2022Regression: Nanite Foliage is a new feature in 5.1, so this issue is not reproduceable in 5.0. Notes about this new support can be found under Nanite Improvements in https://docs.unrealengine.com/5. ...