Spawn enemies off map

Config/DefaultInput.ini

@@ -94,7 +94,7 @@ DoubleClickTime=0.200000
 +ActionMappings=(ActionName="Shoot",bShift=False,bCtrl=False,bAlt=False,bCmd=False,Key=LeftMouseButton)
 +ActionMappings=(ActionName="Shoot",bShift=False,bCtrl=False,bAlt=False,bCmd=False,Key=Gamepad_RightTrigger)
 +ActionMappings=(ActionName="Boost",bShift=False,bCtrl=False,bAlt=False,bCmd=False,Key=RightMouseButton)
-+ActionMappings=(ActionName="Boost",bShift=False,bCtrl=False,bAlt=False,bCmd=False,Key=Gamepad_RightShoulder)
++ActionMappings=(ActionName="Boost",bShift=False,bCtrl=False,bAlt=False,bCmd=False,Key=Gamepad_LeftTrigger)
 +AxisMappings=(AxisName="MoveForward",Scale=1.000000,Key=W)
 +AxisMappings=(AxisName="MoveForward",Scale=-1.000000,Key=S)
 +AxisMappings=(AxisName="MoveRight",Scale=1.000000,Key=D)

Source/PresidentsBrigade/EnemySpawner.cpp

@@ -9,7 +9,10 @@ AEnemySpawner::AEnemySpawner()
  	// Set this actor to call Tick() every frame.  You can turn this off to improve performance if you don't need it.
 	PrimaryActorTick.bCanEverTick = true;
 
+	level_location = TUniquePtr<LevelLocation>(new LevelLocation());
+
 	spawn_delay_s = 5.0f;
+	max_spawn_count = 5;
 }
 
 // Called when the game starts or when spawned
@@ -27,6 +30,10 @@ void AEnemySpawner::BeginPlay()
 void AEnemySpawner::Tick(float delta_s)
 {
 	Super::Tick(delta_s);
+	if (!level_location->is_initialized())
+	{
+		level_location->initialize(GetWorld(), marker_class);
+	}
 
 	spawn_wait_s += delta_s;
 	if (next_spawn_threshold_s == 0)
@@ -35,23 +42,30 @@ void AEnemySpawner::Tick(float delta_s)
 	}
 	else if (spawn_wait_s > next_spawn_threshold_s)
 	{
-		FActorSpawnParameters spawnParameters;
-		spawnParameters.SpawnCollisionHandlingOverride = ESpawnActorCollisionHandlingMethod::AlwaysSpawn;
-		spawnParameters.Owner = this;
-		AAIController* controller = GetWorld()->SpawnActor<AAIController>(
-			controller_class,
-			GetActorLocation(),
-			FRotator(0,0,0),
-			spawnParameters
-		);
+		const int spawn_count = random.RandRange(0, max_spawn_count);
+
+		for (int i = 0; i < spawn_count; i++)
+		{
+			const FVector location = level_location->get_random_mark();
+			FActorSpawnParameters spawnParameters;
+			spawnParameters.SpawnCollisionHandlingOverride = ESpawnActorCollisionHandlingMethod::AlwaysSpawn;
+			spawnParameters.Owner = this;
+			AAIController* controller = GetWorld()->SpawnActor<AAIController>(
+				controller_class,
+				location,
+				FRotator(0,0,0),
+				spawnParameters
+			);
+
+			ABasePawn* enemy = GetWorld()->SpawnActor<ABasePawn>(
+				pawn_class,
+				location,
+				FRotator(0,0,0),
+				spawnParameters
+			);
+			controller->Possess(enemy);
+		}
 
-		ABasePawn* enemy = GetWorld()->SpawnActor<ABasePawn>(
-			pawn_class,
-			GetActorLocation(),
-			FRotator(0,0,0),
-			spawnParameters
-		);
-		controller->Possess(enemy);
 		spawn_wait_s = 0;
 		next_spawn_threshold_s = spawn_delay_s + random.GetFraction();
 	}

Source/PresidentsBrigade/EnemySpawner.h

@@ -6,6 +6,7 @@
 #include "GameFramework/Actor.h"
 #include "BasePawn.h"
 #include "AIController.h"
+#include "LevelLocation.h"
 #include "EnemySpawner.generated.h"
 
 UCLASS()
@@ -41,8 +42,25 @@ protected:
 	UPROPERTY(EditAnywhere, Category = "Enemy")
 	TSubclassOf<AAIController> controller_class;
 
+	/**
+	 * Enemy spawn location marker.
+	 */
+	UPROPERTY(EditAnywhere, Category = "Enemy")
+	UClass* marker_class;
+
+	/**
+	 * Max number of enemies to spawn in one cycle.
+	 */
+	UPROPERTY(EditAnywhere, Category = "Enemy")
+	int max_spawn_count;
+
 private:
 
+	/**
+	 * Level location.
+	 */
+	TUniquePtr<LevelLocation> level_location;
+
 	/**
 	 * Random number stream.
 	 */

Source/PresidentsBrigade/LevelLocation.cpp

@@ -0,0 +1,73 @@
+// Fill out your copyright notice in the Description page of Project Settings.
+
+
+#include "LevelLocation.h"
+#include "EngineUtils.h"
+#include "Util.h"
+
+#define LogError(Msg) Util::log_error(TEXT("LevelLocation"), Msg)
+
+LevelLocation::LevelLocation()
+{
+}
+
+LevelLocation::~LevelLocation()
+{
+}
+
+bool LevelLocation::is_initialized() const
+{
+	return initialized;
+}
+
+/**
+ * Initialize this class with a list of locations derived from the current world.
+ */
+void LevelLocation::initialize(UWorld *world, const UClass *marker_class) 
+{
+	initialized = true;
+
+	/*
+	 * Find all the markers in the world.
+	 */
+	for (TActorIterator<AActor> iterator(world); iterator; ++iterator)
+	{
+		AActor* actor = *iterator;
+		if (actor)
+		{
+			UClass* actor_class = actor->GetClass();
+
+			if (actor_class == marker_class)
+			{
+				locations.Add(actor->GetActorLocation());
+			}
+		}
+	}
+	
+	if (locations.Num() == 0)
+	{
+		LogError("No markers");
+	}
+
+	/*
+	 * Initialize random stream.
+	 */
+	random.Initialize(FMath::Rand());
+}
+
+/**
+ * Get world location of randomly selected mark.
+ * 
+ * @return World location vector of mark.
+ */
+FVector LevelLocation::get_random_mark() const
+{
+	if (locations.Num() == 0)
+	{
+		LogError("No markers");
+		return FVector();
+	}
+
+	const int index = random.RandRange(0, locations.Num() - 1);
+	return locations[index];
+}

Source/PresidentsBrigade/LevelLocation.h

@@ -0,0 +1,35 @@
+// Fill out your copyright notice in the Description page of Project Settings.
+
+#pragma once
+
+#include "CoreMinimal.h"
+
+/**
+ * 
+ */
+class PRESIDENTSBRIGADE_API LevelLocation
+{
+public:
+	LevelLocation();
+	~LevelLocation();
+
+	void initialize(UWorld *world, const UClass *marker_class);
+	FVector get_random_mark() const;
+	bool is_initialized() const;
+
+private:
+	/**
+	 * True when initialized.
+	 */
+	bool initialized = false;
+
+	/**
+	 * Random number stream.
+	 */
+	FRandomStream random;
+
+	/**
+	 * List of locations.
+	 */
+	TArray<FVector> locations;
+};

Source/PresidentsBrigade/PresidentAIController.cpp

@@ -8,6 +8,11 @@
 #define LogInfo(Msg) Util::log_info(TEXT("APresidentAIController"), Msg)
 #define LogError(Msg) Util::log_error(TEXT("APresidentAIController"), Msg)
 
+APresidentAIController::APresidentAIController()
+{
+	level_location = TUniquePtr<LevelLocation>(new LevelLocation());
+}
+
 void APresidentAIController::BeginPlay()  
 {
     Super::BeginPlay();
@@ -31,7 +36,7 @@ void APresidentAIController::Tick(float delta)
 		const FVector offset(1.0, 1.0, 0);
 		starting_location = GetPawn()->GetActorLocation() + offset;
 		target_location = starting_location;
-		marker_locations = get_markers();
+		level_location->initialize(GetWorld(), marker_class);
 
 		// Update state.
 		current_state = state_t::idle;
@@ -47,7 +52,7 @@ void APresidentAIController::Tick(float delta)
 		}
 		else
 		{
-			target_location = is_home ? get_random_mark() : starting_location;
+			target_location = is_home ? level_location->get_random_mark() : starting_location;
 			MoveToLocation(target_location);
 			current_state = state_t::moving;
 		}
@@ -80,50 +85,3 @@ void APresidentAIController::OnMoveCompleted(FAIRequestID request_id, const FPat
 {
 	move_completed = true;
 }
-
-
-/**
- * Helper function to load all the markers in the level.
- */
-TArray<FVector> APresidentAIController::get_markers() const
-{
-	TArray<FVector> locations;
-	for (TActorIterator<AActor> iterator(GetWorld()); iterator; ++iterator)
-	{
-		AActor* actor = *iterator;
-		if (actor && actor != this)
-		{
-			UClass* actor_class = actor->GetClass();
-
-			if (actor_class == marker_class)
-			{
-				locations.Add(actor->GetActorLocation());
-			}
-		}
-	}
-	
-	if (locations.Num() == 0)
-	{
-		LogError("No markers");
-	}
-
-	return locations;
-}
-
-/**
- * Helper function for returning world location of randomly selected mark.
- * 
- * @return World location vector of mark.
- */
-FVector APresidentAIController::get_random_mark() const
-{
-	if (marker_locations.Num() == 0)
-	{
-		LogError("No markers");
-		return FVector();
-	}
-
-	const int index = random.RandRange(0, marker_locations.Num() - 1);
-	return marker_locations[index];
-}
-

Source/PresidentsBrigade/PresidentAIController.h

@@ -4,6 +4,7 @@
 
 #include "CoreMinimal.h"
 #include "AIController.h"
+#include "LevelLocation.h"
 #include "PresidentAIController.generated.h"
 
 /**
@@ -15,6 +16,8 @@ class PRESIDENTSBRIGADE_API APresidentAIController : public AAIController
 	GENERATED_BODY()
 
 public:
+	APresidentAIController();
+
 	virtual void Tick(float delta) override;
 
 protected:
@@ -34,13 +37,10 @@ private:
 		waiting
 	};
 
-	TArray<FVector> get_markers() const;
-	FVector get_random_mark() const;
-
 	/**
-	 * List of marker locations.
+	 * Level location tracker.
 	 */
-	TArray<FVector> marker_locations;
+	TUniquePtr<LevelLocation> level_location;
 
 	/**
 	 * Random number stream.