Bug Report: Crash when changing TargetArmLength in C++

Development Programming & Scripting C++
1

Hello, just to report a bug

I added a Custom C++ PlayerController class and made a Blueprint inheriting of this class, This BP class is the PlayerController asgined to the player.

I made a Getter for the CameraBoom in the player class

in the C++ playercontroller header I have a reference to the player


class APlayerClass *Player;

then in C++ PlayerController Begin Play…


 Player = static_cast<APlayerClass*>(UGameplayStatics::GetPlayerCharacter(this, 0));

InitialCameraBoomLenght = Player->GetCameraBoom()->TargetArmLength;

And then in the C++ PlayerController Tick I have this lines


if (Player) {
          Player->GetCameraBoom()->SetWorldRotation(FRotator(CameraBoomDesiredPitch, CameraBoomDesiredRotation, 0));
}

Everything compiles well and run as I exepected, but If I try to open the PLAYERCONTROLLER BLUEPRINT inherithing this C++ PlayerController Class the system Crashes, If I comment the line changin the value of cameraboom the PlayerController Blueprint opens normaly

the same error occurs with this line


if (Player) {
	Player->GetCameraBoom()->TargetArmLength = InitialCameraBoomLenght + CameraBoomDesiredLenght;
}
2

Looks like you have accessed the Null Pointer.
Have you debugged?
Or try to return the function, when Player is not exist.

3

Your cast is wrong. You should be using the UE4 Cast function.



Player = static_cast<APlayerClass*>(UGameplayStatics::GetPlayerCharacter(this, 0));

Should be:



APlayerClass* Player = Cast<APlayerClass>(UGameplayStatics::GetPlayerCharacter(this, 0));

I almost guarantee you that this is a nullptr / access violation crash.