Class causes editor to crash when deleting it form a BP and/or recompiling the BP

Development Programming & Scripting C++
1

I’ve got an atmosphere class that contains pointer to World Light, Atmosphere Fog, Exponential Height Fog and Audio Component:

header:


	UPROPERTY(EditAnywhere) UDirectionalLightComponent* WorldLight = nullptr;		
	UPROPERTY(EditAnywhere) UAtmosphericFogComponent* AtmosphereFog = nullptr;		
	UPROPERTY(EditAnywhere) UExponentialHeightFogComponent* HeightFog = nullptr;	
	UPROPERTY(EditAnywhere) UAudioComponent* AmbientSound = nullptr;

cpp:


    AAtmosphere::AAtmosphere()
    {
     	PrimaryActorTick.bCanEverTick = false;
    
    	AmbientSound = CreateDefaultSubobject<UAudioComponent>(FName(TEXT("Ambient Sound")));
    	WorldLight = CreateDefaultSubobject<UDirectionalLightComponent>(FName(TEXT("World Light")));
    	AtmosphereFog = CreateDefaultSubobject<UAtmosphericFogComponent>(FName(TEXT("Atmosphere Fog")));
    	HeightFog = CreateDefaultSubobject<UExponentialHeightFogComponent>(FName(TEXT("Height Fog")));;
    }

This class is used as a child to my AtomsphereController class.

header:


        UPROPERTY(EditAnywhere)    	AAtmosphere* Atmosphere = nullptr;
        APlayerController* MyController = nullptr;

cpp:



    AtmosphereController::UAtmosphereController()
    {
    	bWantsBeginPlay = true;
    	PrimaryComponentTick.bCanEverTick = false;		
    	Atmosphere = CreateDefaultSubobject<AAtmosphere>(FName(TEXT("Atmosphere")));
    }

Now, this AtmosphereController is attached to an actor in my game that is suppose to have control over the atmosphere. If I attach it to this blueprint, I can safely compile ONE time. At this point, the game will run fine in the editor (PIE), and execute as expected. BUT, if I try to compile the BP a second time (no changes, just a mere click of the Compile button) or delete the AtmosphereController from the BP… insta-crash. I know it has something to do with the AtmosphereController’s call to CreateDefaultSubobject, because I can comment it out, recompile the game, and then delete it from my BP. But once I uncomment, and recompile my BP for a second time, it starts crashing again.

Can someone explain WHY this is causing such an awkward side effect?

2

I don’t think Actors (any class deriving from AActor) can be spawned in a constructor, and therefore cannot be used with CreateDefaultSubobject either. Instead you should probably spawn the AAtmosphere in BeginPlay or consider placing an AAtmosphere instance in the level editor.

3

My atmosphere class DOES actually spawn this way. If I run PIE, my wield gets light and fog (haven’t tested the audio component, but I would assume it dies as well). But I WILL go a ahead and try to move the atmosphere into a spawn actor call from begin play. Thank you for the suggestion.