Engine crash when i try to check if an actor array element isn't null

Development Programming & Scripting
1

So, I am trying to make a spawn system to my game so the enemies will automatically spawn when i get close to a target point and only one enemy can be in the scene per target point, but whenever I run the game with this code the editor instantly crashes and I can’t figure out why. I’ve made some tests and the problem is definitely in the SpawnEnemy function, but not bellow the second if.

.cpp file:

#include "CUGameMode.h"
#include "BOTEnemy.h"
#include "Kismet/GameplayStatics.h"
#include "Engine/World.h"
#include "Public/TimerManager.h"
#include "Engine.h"

ACUGameMode::ACUGameMode()
{
	PrimaryActorTick.bCanEverTick = true;
}

void ACUGameMode::BeginPlay()
{
	Super::BeginPlay();
	UGameplayStatics::GetAllActorsOfClass(GetWorld(), SpawnerClass, Spawners);
}

void ACUGameMode::SpawnEnemy()
{
	for (int i = 0; i < Spawners.Num(); i++)
	{
		if (Spawners[i]->GetDistanceTo(Cast<AActor>(UGameplayStatics::GetPlayerCharacter(GetWorld(), 0))) < 7000.f)
		{
			if (!SpawnedEnemies[i])
			{
				FTransform SpawnerTransform = Spawners[i]->GetActorTransform();
				EEnemyType SpawnedEnemyType = EEnemyType::Barghest;
				if (Spawners[i]->ActorHasTag("BarghestSpawner"))
				{
					SpawnedEnemyType = EEnemyType::Barghest;
				}
				SpawnedEnemies[i] = GetWorld()->SpawnActorDeferred<ABOTEnemy>(ClassToSpawn, SpawnerTransform);
				SpawnedEnemies[i]->TipoDoInimigo = SpawnedEnemyType;
				SpawnedEnemies[i]->FinishSpawning(SpawnerTransform);
			}
		}
	}
}

void ACUGameMode::SpawnerTimer()
{
	bCanSpawn = true;
}

void ACUGameMode::Tick(float DeltaTime)
{
	Super::Tick(DeltaTime);
	UGameplayStatics::GetAllActorsOfClass(GetWorld(), ABOTEnemy::StaticClass(), EnemiesSpawned);
	if (EnemiesSpawned.Num() < 10 && bCanSpawn)
	{
		SpawnEnemy();
		bCanSpawn = false;
		GetWorldTimerManager().SetTimer(SpawnTimer, this, &ACUGameMode::SpawnerTimer, 2.f, false);
	}
}

.h file:

#pragma once

#include "CoreMinimal.h"
#include "GameFramework/GameModeBase.h"
#include "CUGameMode.generated.h"

/**
 * 
 */
UCLASS()
class CU_API ACUGameMode : public AGameModeBase
{
	GENERATED_BODY()
private:
	virtual void BeginPlay() override;
	FTimerHandle SpawnTimer;
	TArray<class AActor*> Spawners;
	TArray<class AActor*> EnemiesSpawned;
	TArray<class ABOTEnemy*> SpawnedEnemies;
	UPROPERTY(EditAnywhere, Category = "Class")
	TSubclassOf<class AActor> SpawnerClass;
	UPROPERTY(EditAnywhere, Category = "Class")
	TSubclassOf<class ABOTEnemy> ClassToSpawn;
	UFUNCTION()
	void SpawnEnemy();
	UFUNCTION()
	void SpawnerTimer();
	bool bCanSpawn = true;

public:
	ACUGameMode();
	virtual void Tick(float DeltaTime) override;
};
2

I have made some more tests and now I am sure the problem is in the if on line 25 of cpp file but still cant figure out what is wrong though.

3

Try Changing line 17 in the .h file from:

TArray<class AActor*> Spawners;
TArray<class AActor*> EnemiesSpawned;
TArray<class ABOTEnemy*> SpawnedEnemies;

To:

UPROPERTY()
 TArray<class AActor*> Spawners;

UPROPERTY()     
TArray<class AActor*> EnemiesSpawned;

UPROPERTY()     
TArray<class ABOTEnemy*> SpawnedEnemies;

Further, do you have a crash log?

4

That didn’t did it, the editor is still crashing.

Here is the log:
link text

5

It seems like you uploaded the editor log. Do you have the crash handler open up when the game crashes? The stacktrace in there is what would be needed.

6

Sorry, the window that pops up when the editor crashes just give me a link to the editor log and says I don’t have debugging symbols required to display the callstrack for the crash.

7

Just solved it, the problem was that i hadn’t initialized the array, thanks for the help.