This is information thread and for people who face similar issue.
There is unanswered question on stackoverflow here.
Unverified Reproduce Step
- Add FKControlRig track in MoveSequencer track on UE4.27.0
- Port it to UE5.
- Package to development build and run for a bit. You will get disregard for GC object.
This bug can causes crash in Shipping build.
The causes come from MovieSceneControlRigParameterTrack try to reconstruct UFKControlRig using Class Default Object instead of creating a new instance of UFKControlRig.
The Class Default Object is a template that UE uses to create new instance when you call NewObject();
Unverified Work Around.
I work around this by using BlueprintGenratedControlRig. Just create a blueprint and let it inherit UFKControlRig.
Then you need to copy keyframes and remove FKControlRig track from MovieSequencer.
How to easy find the FKControlRig track?
- Log the information here https://github.com/EpicGames/UnrealEngine/blob/release/Engine/Plugins/Animation/ControlRig/Source/ControlRig/Private/ControlRig.cpp#L2788-L2803
- Also Log information here
https://github.com/EpicGames/UnrealEngine/blob/release/Engine/Plugins/Animation/ControlRig/Source/ControlRig/Private/Sequencer/MovieSceneControlRigParameterTrack.cpp#L371-L372
I didn’t report bug yet because I don’t have time to do actual reproduce steps yet.
Hope this help people who face similar issue.