Switching Between Multiple Tanks

[Ekam_Singh]

Hello, I placed 4 tanks on the map and added some code to switch between them whenever a projectile is fired. I can get the PlayerController to possess a new tank, but for some reason the turret mesh only rotates around for the original tank from Player Start (as seen in the gif below).

When I try to log out the tank being controlled,

	FString PawnName = UGameplayStatics::GetPlayerController(this, 0)->GetPawn()->GetActorNameOrLabel();
	UE_LOG(LogTemp, Display, TEXT("[Testing] Turrent Mesh belongs to: %s %s"), *TurretMesh->GetOwner()->GetActorNameOrLabel(), *PawnName);

LogTemp: Display: [Testing] Turrent Mesh belongs to: BP_PawnTank BP_PawnTank
LogTemp: Display: [Testing] Turrent Mesh belongs to: BP_PawnTank Tank3

The Tank get’s updated for the PlayerController, but the turret mesh always has the original player start tank as the owner.

I added a Timer inside AProjectile::onHit and calls ChangePlayer inside AToonTanksPlayerController.

The Towers all rotate independently. Is there something I am missing in order to rotate the turret mesh individually for each tank?

[DanM]

How do you rotate the tank’s turret?

[Ekam_Singh]

It’s the same way as the lecture inside the Tick function of Tank.cpp.

void ATank::Tick(float DeltaTime)
{
	Super::Tick(DeltaTime);

	if (TankPlayerController)
	{
		FHitResult HitResult;
		TankPlayerController->GetHitResultUnderCursor(ECollisionChannel::ECC_Visibility, false, HitResult);
		//DrawDebugSphere(GetWorld(), HitResult.ImpactPoint, 10, 10, FColor::Red, false, -1);
		RotateTurret(HitResult.ImpactPoint);
		UE_LOG(LogTemp, Display, TEXT("[TESTING] PLAYER CONTROLLER PAWN: %s"), *TankPlayerController->GetPawn()->GetActorNameOrLabel())
	}
}

And then the RotateTurret inside BasePawn.cpp

void ABasePawn::RotateTurret(FVector LookAtTarget)
{
	UE_LOG(LogTemp, Warning, TEXT("IS CHILD OF: %d"), UGameplayStatics::GetPlayerController(this, 0)->GetPawn()->GetClass()->IsChildOf(ATank::StaticClass()));
	FVector ToTarget = LookAtTarget - TurretMesh->GetComponentLocation();
	FRotator LookAtRotation = FRotator(0.f, ToTarget.Rotation().Yaw, 0.f);
	FString PawnName = UGameplayStatics::GetPlayerController(this, 0)->GetPawn()->GetActorNameOrLabel();
	UE_LOG(LogTemp, Display, TEXT("[Testing] Turrent Mesh belongs to: %s %s"), *TurretMesh->GetOwner()->GetActorNameOrLabel(), *PawnName);
	TurretMesh->SetWorldRotation(FMath::RInterpTo(TurretMesh->GetComponentRotation(), LookAtRotation, UGameplayStatics::GetWorldDeltaSeconds(this), 5.f));
}

[DanM]

Sorry, that was intended to be a hint to the issue. To be a little more speciific

if (TankPlayerController)

What is the value of TankPlayerController for all tanks. Does it change when you swap tanks?

[Ekam_Singh]

Yes the value for TankPlayerController does change when I swap tanks. I thought it wouldn’t be doing that.

If I use UGameplayStatics::GetPlayerController(this, 0)->GetHit… inside the Tick function instead of TankPlayerController->GetHit…, then it rotates every tank simultaneously but I guess that makes sense because it’s being called for each instance of the Tank Class.

void ATank::Tick(float DeltaTime)
{
	Super::Tick(DeltaTime);

		FHitResult HitResult;
		UGameplayStatics::GetPlayerController(this, 0)->GetHitResultUnderCursor(ECollisionChannel::ECC_WorldStatic, false, HitResult);
		DrawDebugSphere(GetWorld(), HitResult.ImpactPoint, 10, 10, FColor::Red, false, -1);
		RotateTurret(HitResult.ImpactPoint);
		if (TankPlayerController)
	{
		UE_LOG(LogTemp, Display, TEXT("[PLAYERCONTROLLER] PLAYER CONTROLLER PAWN: %s"), *TankPlayerController->GetPawn()->GetActorNameOrLabel())
	}
}

But I found a solution by binding the mouse movement to the Tank Class and then calling RotateTurretAlt from the BasePawn class.

PlayerInputComponent->BindAxis(TEXT("RotateTurret"), this, &ATank::RotateTurretAlt);

void ATank::RotateTurretAlt(float Value)
{
	RotateTankTurret(Value);
}

And then in BasePawn.cpp

void ABasePawn::RotateTankTurret(float Value)
{
	FHitResult HitResult;
	UGameplayStatics::GetPlayerController(this, 0)->GetHitResultUnderCursor(ECollisionChannel::ECC_WorldStatic, false, HitResult);
	DrawDebugSphere(GetWorld(), HitResult.ImpactPoint, 10, 10, FColor::Red, false, -1);
	FVector ToTarget = HitResult.ImpactPoint - TurretMesh->GetComponentLocation();
	FRotator LookAtRotation = FRotator(0.f, ToTarget.Rotation().Yaw, 0.f);
	FString PawnName = UGameplayStatics::GetPlayerController(this, 0)->GetPawn()->GetActorNameOrLabel();
	UE_LOG(LogTemp, Display, TEXT("[BasePawn RotateTankTurret] Turrent Mesh belongs to: %s %s and movement is: %s"), *TurretMesh->GetOwner()->GetActorNameOrLabel(), *PawnName, *LookAtRotation.ToString());
	TurretMesh->SetWorldRotation(FMath::RInterpTo(TurretMesh->GetComponentRotation(), LookAtRotation, UGameplayStatics::GetWorldDeltaSeconds(this), 5.f));

}

Is this a good way to do it or is there a better solution?

[DanM]

Instead of storing it from BeginPlay you can just call GetController and cast in tick. As the tank is only controlled by a playercontroller you can use CastChecked which does the checking for you and is turned into a static cast in shipping builds.

Alternatively swap it when you change player, or alternatively again, override PossessedBy() and UnPossessed()