Packaging fails for an exclusively-nativized BP-only project that includes a non-nativized child Blueprint class that's referenced by an (unrelated) nativized Blueprint class.

UE - Gameplay - Blueprint - Jun 21, 2018

For unknown reason, the header of BP_Parent is included twice. The second header is located after the .generated.h, causing the compile error. The following is the include section of BP_Child__pf1 ...

Material attribute layers issue with texture sample and VT lookups

UE - Rendering Architecture - Materials - Nov 14, 2024

When using material attribute layers in a material layer setup, there is a potential discrepancy in the number of VT Lookups presented in the material instance's Platform Stats. When the same textur ...

[bug] OIT doesn't work correctly with alpha composite blend mode

UE - Graphics Features - Substrate - Mar 4, 2025

When using OIT, AlphaComposite Materials blend as if they are using the Translucent BlendMode. The order of macro #if … #elif cases cause AlphaComposite Materials to take the same route as Transluce ...

Importing static mesh while a PIE session is running permanently breaks nanite on the asset

UE - Editor - Content Pipeline - Import and Export - Mar 12, 2025

Importing a Static Mesh during PIE can cause it to never enable Nanite, even if it reports that Nanite is enabled. To re-enable Nanite on the mesh, the asset needs to be deleted and imported again ...

Cannot Increment a Blackboard Key Value

UE - Gameplay - Blueprint - Feb 4, 2016

Getting a blackboard value as int and then attempting to increment it does not actually increment the value. Upon attempting to increment a value that started at 0, the editor continued to print out ...

Closing a Geometry's Collection Dataflow Editor window when the ChaosVehiclePlugin is enabled is crashing the Unreal Editor when running it with the -stompmalloc flag

UE - Simulation - Physics - Jan 27, 2025

As the title describes, closing a Geometry's Collection Dataflow Editor window when the ChaosVehiclePlugin is enabled is crashing the Unreal Editor when it is running with the -stompmalloc flag. The ...

Hot reload causes AnimBlueprint to lose functionality and crash

OLD - Anim - Mar 31, 2015

Casting to a character class inside of AnimBlueprint after a hot reload caused editor to crash Crash Reporter: [Link Removed] Additionally, Casts fail, breaking AnimBlueprint after a hot reload ...

Overlapping isn't updated on replicated components after SetWorldTransform

UE - Networking - Dec 10, 2015

Overlapping isn't updated on replicated components after SetWorldTransform. Updating the transform on the Actor itself updates the overlapping as expected. Reproduced in 4.10 and Main (CL# 2798114) ...

iOS Metal-based build crashes at launch with sub-levels.

Tools - May 16, 2016

Application crashes when deploying a game to iOS with Metal enabled. This has only been reproduced if a sub-level has been added to the starting level within the project. This seems to only happen ...

Crash closing a project that was packaged on Windows for Linux

Tools - May 11, 2017

This occurred with both Development and DebugGame build configurations. In the game's console I tried both "quit" and "exit" and reproed the crash. The crash also occurs via Alt + F4 or closing vi ...