Section 15: AI and Behavior Trees - Lecture 297

Weapon Trails

Source/Shooter/Enemy.cpp

@@ -13,6 +13,8 @@
 #include "BehaviorTree/BlackboardComponent.h"
 #include "Components/SphereComponent.h"
 #include "ShooterCharacter.h"
+#include "Components/BoxComponent.h"
+#include "Components/CapsuleComponent.h"
 
 // Sets default values
 AEnemy::AEnemy() :
@@ -24,7 +26,12 @@ AEnemy::AEnemy() :
 	bCanHitReact(true),
 	HitNumberDestroyTime(1.5f),
 	bStunned(false),
-	StunChance(.5f)
+	StunChance(.5f),
+	AttackLFast(TEXT("AttackLFast")),
+	AttackRFast(TEXT("AttackRFast")),
+	AttackL(TEXT("AttackL")),
+	AttackR(TEXT("AttackR")),
+	BaseDamage(20.f)
 {
  	// Set this character to call Tick() every frame.  You can turn this off to improve performance if you don't need it.
 	PrimaryActorTick.bCanEverTick = true;
@@ -32,6 +39,17 @@ AEnemy::AEnemy() :
 	// Create the Agro Sphere
 	AgroSphere = CreateDefaultSubobject<USphereComponent>(TEXT("AgroSphere"));
 	AgroSphere->SetupAttachment(GetRootComponent());
+	
+	// Create the Combat Range Sphere
+	CombatRangeSphere = CreateDefaultSubobject<USphereComponent>(TEXT("CombatRangeSphere"));
+	CombatRangeSphere->SetupAttachment(GetRootComponent());
+
+	// Construct left and right weapon collision boxes
+	LeftWeaponCollision = CreateDefaultSubobject<UBoxComponent>(TEXT("Left Weapon Box"));
+	LeftWeaponCollision->SetupAttachment(GetMesh(), FName("LeftWeaponBone"));
+	
+	RightWeaponCollision = CreateDefaultSubobject<UBoxComponent>(TEXT("Right Weapon Box"));
+	RightWeaponCollision->SetupAttachment(GetMesh(), FName("RightWeaponBone"));
 }
 
 // Called when the game starts or when spawned
@@ -40,8 +58,27 @@ void AEnemy::BeginPlay()
 	Super::BeginPlay();
 
 	AgroSphere->OnComponentBeginOverlap.AddDynamic(this, &AEnemy::AgroSphereOverlap);
+	CombatRangeSphere->OnComponentBeginOverlap.AddDynamic(this, &AEnemy::CombatRangeOverlap);
+	CombatRangeSphere->OnComponentEndOverlap.AddDynamic(this, &AEnemy::CombatRangeEndOverlap);
+
+	// Bind functions to overlap events for weapon boxes
+	LeftWeaponCollision->OnComponentBeginOverlap.AddDynamic(this, &AEnemy::OnLeftWeaponOverlap);
+	RightWeaponCollision->OnComponentBeginOverlap.AddDynamic(this, &AEnemy::OnRightWeaponOverlap);
+
+	// Set collision presets for weapon boxes
+	LeftWeaponCollision->SetCollisionEnabled(ECollisionEnabled::NoCollision);
+	LeftWeaponCollision->SetCollisionObjectType(ECollisionChannel::ECC_WorldDynamic);
+	LeftWeaponCollision->SetCollisionResponseToAllChannels(ECollisionResponse::ECR_Ignore);
+	LeftWeaponCollision->SetCollisionResponseToChannel(ECollisionChannel::ECC_Pawn, ECollisionResponse::ECR_Overlap);
+	
+	RightWeaponCollision->SetCollisionEnabled(ECollisionEnabled::NoCollision);
+	RightWeaponCollision->SetCollisionObjectType(ECollisionChannel::ECC_WorldDynamic);
+	RightWeaponCollision->SetCollisionResponseToAllChannels(ECollisionResponse::ECR_Ignore);
+	RightWeaponCollision->SetCollisionResponseToChannel(ECollisionChannel::ECC_Pawn, ECollisionResponse::ECR_Overlap);
 	
 	GetMesh()->SetCollisionResponseToChannel(ECollisionChannel::ECC_Visibility, ECollisionResponse::ECR_Block);
+	GetMesh()->SetCollisionResponseToChannel(ECollisionChannel::ECC_Camera, ECollisionResponse::ECR_Ignore);
+	GetCapsuleComponent()->SetCollisionResponseToChannel(ECollisionChannel::ECC_Camera, ECollisionResponse::ECR_Ignore);
 
 	// Get the AI Controller
 	EnemyController = Cast<AEnemyController>(GetController());
@@ -75,7 +112,8 @@ void AEnemy::PlayHitMontage(FName Section, float PlayRate)
 {
 	if (!bCanHitReact) return;
 	
-	if (UAnimInstance* AnimInstance = GetMesh()->GetAnimInstance())
+	UAnimInstance* AnimInstance = GetMesh()->GetAnimInstance();
+	if (AnimInstance && HitMontage)
 	{
 		AnimInstance->Montage_Play(HitMontage, PlayRate);
 		AnimInstance->Montage_JumpToSection(Section, HitMontage);
@@ -140,6 +178,104 @@ void AEnemy::SetStunned(bool Stunned)
 	EnemyController->GetBlackboardComponent()->SetValueAsBool(TEXT("Stunned"), Stunned);
 }
 
+void AEnemy::CombatRangeOverlap(UPrimitiveComponent* OverlappedComponent, AActor* OtherActor,
+	UPrimitiveComponent* OtherComp, int32 OtherBodyIndex, bool bFromSweep, const FHitResult& SweepResult)
+{
+	if (!OtherActor) return;
+	if (Cast<AShooterCharacter>(OtherActor) == nullptr) return;
+
+	bInAttackRange = true;
+	
+	if (!EnemyController) return;
+	EnemyController->GetBlackboardComponent()->SetValueAsBool(TEXT("InAttackRange"), true);
+	UE_LOG(LogTemp, Warning, TEXT("overlap player"));
+}
+
+void AEnemy::CombatRangeEndOverlap(UPrimitiveComponent* OverlappedComponent, AActor* OtherActor,
+	UPrimitiveComponent* OtherComp, int32 OtherBodyIndex)
+{
+	if (!OtherActor) return;
+	if (Cast<AShooterCharacter>(OtherActor) == nullptr) return;
+	
+	bInAttackRange = false;
+	
+	if (!EnemyController) return;
+	EnemyController->GetBlackboardComponent()->SetValueAsBool(TEXT("InAttackRange"), false);
+	UE_LOG(LogTemp, Warning, TEXT("end overlap player"));
+}
+
+void AEnemy::PlayAttackMontage(FName Section, float PlayRate)
+{
+	UAnimInstance* AnimInstance = GetMesh()->GetAnimInstance(); 
+	if (AnimInstance && AttackMontage)
+	{
+		AnimInstance->Montage_Play(AttackMontage, PlayRate);
+		AnimInstance->Montage_JumpToSection(Section, AttackMontage);
+	}
+}
+
+FName AEnemy::GetAttackSectionName() const
+{
+	switch (FMath::RandRange(1, 4))
+	{
+	case 1:
+		return AttackLFast;
+	case 2:
+		return AttackRFast;
+	case 3:
+		return AttackL;
+	case 4:
+		return AttackR;
+	default:
+		return AttackLFast;
+	}
+}
+
+void AEnemy::DoDamage(AActor* Victim)
+{
+	if (!Victim) return;
+	if (auto const Character = Cast<AShooterCharacter>(Victim))
+	{
+		UGameplayStatics::ApplyDamage(Character, BaseDamage, EnemyController, this, UDamageType::StaticClass());
+		if (USoundCue* MeleeImpactSound = Character->GetMeleeImpactSound())
+		{
+			UGameplayStatics::PlaySoundAtLocation(this, MeleeImpactSound, GetActorLocation());
+		}
+	}
+}
+
+void AEnemy::OnLeftWeaponOverlap(UPrimitiveComponent* OverlappedComponent, AActor* OtherActor,
+	UPrimitiveComponent* OtherComp, int32 OtherBodyIndex, bool bFromSweep, const FHitResult& SweepResult)
+{
+	DoDamage(OtherActor);
+}
+
+void AEnemy::OnRightWeaponOverlap(UPrimitiveComponent* OverlappedComponent, AActor* OtherActor,
+	UPrimitiveComponent* OtherComp, int32 OtherBodyIndex, bool bFromSweep, const FHitResult& SweepResult)
+{
+	DoDamage(OtherActor);
+}
+
+void AEnemy::ActivateLeftWeapon()
+{
+	LeftWeaponCollision->SetCollisionEnabled(ECollisionEnabled::QueryOnly);
+}
+
+void AEnemy::DeactivateLeftWeapon()
+{
+	LeftWeaponCollision->SetCollisionEnabled(ECollisionEnabled::NoCollision);
+}
+
+void AEnemy::ActivateRightWeapon()
+{
+	RightWeaponCollision->SetCollisionEnabled(ECollisionEnabled::QueryOnly);
+}
+
+void AEnemy::DeactivateRightWeapon()
+{
+	RightWeaponCollision->SetCollisionEnabled(ECollisionEnabled::NoCollision);
+}
+
 // Called every frame
 void AEnemy::Tick(float DeltaTime)
 {

Source/Shooter/Enemy.h

@@ -13,6 +13,7 @@ class UAnimMontage;
 class UBehaviorTree;
 class AEnemyController;
 class USphereComponent;
+class UBoxComponent;
 
 UCLASS()
 class SHOOTER_API AEnemy : public ACharacter, public IBulletHitInterface
@@ -48,6 +49,12 @@ protected:
 
 	void UpdateHitNumbers();
 
+	UFUNCTION(BlueprintCallable)
+	float GetHealth() const { return Health; }
+	
+	UFUNCTION(BlueprintCallable)
+	float GetMaxHealth() const { return MaxHealth; }
+
 	/** Called when something overlaps with the agro sphere */
 	UFUNCTION()
 	void AgroSphereOverlap(UPrimitiveComponent* OverlappedComponent, AActor* OtherActor,
@@ -56,6 +63,43 @@ protected:
 
 	UFUNCTION(BlueprintCallable)
 	void SetStunned(bool Stunned);
+
+	UFUNCTION()
+	void CombatRangeOverlap(UPrimitiveComponent* OverlappedComponent, AActor* OtherActor,
+		UPrimitiveComponent* OtherComp, int32 OtherBodyIndex, bool bFromSweep,
+		const FHitResult& SweepResult);
+	
+	UFUNCTION()
+	void CombatRangeEndOverlap(UPrimitiveComponent* OverlappedComponent, AActor* OtherActor,
+		UPrimitiveComponent* OtherComp, int32 OtherBodyIndex);
+	
+	UFUNCTION(BlueprintCallable)
+	void PlayAttackMontage(FName Section, float PlayRate = 1.0f);
+
+	UFUNCTION(BlueprintPure)
+	FName GetAttackSectionName() const;
+
+	UFUNCTION()
+	void OnLeftWeaponOverlap(UPrimitiveComponent* OverlappedComponent, AActor* OtherActor,
+		UPrimitiveComponent* OtherComp, int32 OtherBodyIndex, bool bFromSweep,
+		const FHitResult& SweepResult);
+	UFUNCTION()
+	void OnRightWeaponOverlap(UPrimitiveComponent* OverlappedComponent, AActor* OtherActor,
+		UPrimitiveComponent* OtherComp, int32 OtherBodyIndex, bool bFromSweep,
+		const FHitResult& SweepResult);
+
+	// Activate/Deactivate collision for weapon boxes
+	UFUNCTION(BlueprintCallable)
+	void ActivateLeftWeapon();
+	UFUNCTION(BlueprintCallable)
+	void DeactivateLeftWeapon();
+
+	UFUNCTION(BlueprintCallable)
+	void ActivateRightWeapon();
+	UFUNCTION(BlueprintCallable)
+	void DeactivateRightWeapon();
+
+	void DoDamage(AActor* Victim);
 private:
 	/** Particles to spawn when hit by bullets */
 	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = Combat, meta = (AllowPrivateAccess = true))
@@ -119,7 +163,7 @@ private:
 	AEnemyController* EnemyController;
 
 	/** Overlap sphere for when the enemy becomes hostile */
-	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Behavior Tree", meta = (AllowPrivateAccess = true))
+	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = Combat, meta = (AllowPrivateAccess = true))
 	USphereComponent* AgroSphere;
 
 	/** True when playing the get hit animation */
@@ -129,6 +173,35 @@ private:
 	/** Chance of being stunned. 0: no stun chance, 1: 100% stun chance */
 	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = Combat, meta = (AllowPrivateAccess = true))
 	float StunChance;
+
+	/** True when in attack rangel; time to attack */
+	UPROPERTY(VisibleAnywhere, BlueprintReadWrite, Category = Combat, meta = (AllowPrivateAccess = true))
+	bool bInAttackRange;
+
+	/** Overlap sphere for attack range */
+	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = Combat, meta = (AllowPrivateAccess = true))
+	USphereComponent* CombatRangeSphere;
+
+	/** Montage containing different attacks */
+	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = Combat, meta = (AllowPrivateAccess = true))
+	UAnimMontage* AttackMontage;
+
+	/** The 4 attack montage section names */
+	FName AttackLFast;
+	FName AttackRFast;
+	FName AttackL;
+	FName AttackR;
+
+	/** Collision volume for the left weapon */
+	UPROPERTY(VisibleAnywhere, BlueprintReadWrite, Category = Combat, meta = (AllowPrivateAccess = true))
+	UBoxComponent* LeftWeaponCollision;
+	
+	/** Collision volume for the right weapon */
+	UPROPERTY(VisibleAnywhere, BlueprintReadWrite, Category = Combat, meta = (AllowPrivateAccess = true))
+	UBoxComponent* RightWeaponCollision;
+
+	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = Combat, meta = (AllowPrivateAccess = true))
+	float BaseDamage;
 public:	
 	// Called every frame
 	virtual void Tick(float DeltaTime) override;

Source/Shooter/ShooterCharacter.cpp

@@ -77,7 +77,9 @@ AShooterCharacter::AShooterCharacter() :
 	PickupSoundResetTime(0.2f),
 	EquipSoundResetTime(0.2f),
 	// Icon animation property
-	HighlightedSlot(-1)
+	HighlightedSlot(-1),
+	Health(100.f),
+	MaxHealth(100.f)
 {
  	// Set this character to call Tick() every frame.  You can turn this off to improve performance if you don't need it.
 	PrimaryActorTick.bCanEverTick = true;
@@ -202,6 +204,23 @@ void AShooterCharacter::SetupPlayerInputComponent(UInputComponent* PlayerInputCo
 	PlayerInputComponent->BindAction("5Key", IE_Pressed, this, &AShooterCharacter::Key5Pressed);
 }
 
+float AShooterCharacter::TakeDamage(float DamageAmount, FDamageEvent const& DamageEvent, AController* EventInstigator,
+	AActor* DamageCauser)
+{
+	float DamageInflicted = DamageAmount;
+	if (Health - DamageAmount <= 0.f)
+	{
+		DamageInflicted = Health; 
+		Health = 0.f;
+		//Die();
+	}
+	else
+	{
+		Health -= DamageAmount;
+	}
+	return DamageInflicted;
+}
+
 // Called every frame
 void AShooterCharacter::Tick(float DeltaTime)
 {

Source/Shooter/ShooterCharacter.h

@@ -63,6 +63,8 @@ public:
 	// Called to bind functionality to input
 	virtual void SetupPlayerInputComponent(class UInputComponent* PlayerInputComponent) override;
 
+	virtual float TakeDamage(float DamageAmount, FDamageEvent const& DamageEvent, AController* EventInstigator, AActor* DamageCauser) override;
+	
 protected:
 	// Called when the game starts or when spawned
 	virtual void BeginPlay() override;
@@ -486,7 +488,18 @@ private:
 	/** The index for the currently highlighted slot */
 	UPROPERTY(VisibleAnywhere, BlueprintReadOnly, Category = Inventory, meta = (AllowPrivateAccess = true))
 	int32 HighlightedSlot;
+	
+	/** Character health */
+	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = Combat, meta = (AllowPrivateAccess = true))
+	float Health;
+	
+	/** Character max health */
+	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = Combat, meta = (AllowPrivateAccess = true))
+	float MaxHealth;
 
+	/** Sound made when character gets hit by a melee attack */
+	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = Combat, meta = (AllowPrivateAccess = true))
+	USoundCue* MeleeImpactSound;
 public:
 	/* Returns CameraBoom SubObject */
 	FORCEINLINE USpringArmComponent* GetCameraBoom() const { return CameraBoom; }
@@ -528,5 +541,20 @@ public:
 
 	void UnhighlightInventorySlot();
 
-	FORCEINLINE AWeapon* GetEquippedWeapon() const { return EquippedWeapon; }
+	UFUNCTION(BlueprintCallable)
+	AWeapon* GetEquippedWeapon() const { return EquippedWeapon; }
+
+	UFUNCTION(BlueprintCallable)
+	TMap<EAmmoType, int32> GetAmmoMap() const { return AmmoMap; }
+
+	UFUNCTION(BlueprintCallable)
+	TArray<AItem*> GetInventory() const { return Inventory; }
+	
+	UFUNCTION(BlueprintCallable)
+	float GetHealth() const	{ return Health; }
+	
+	UFUNCTION(BlueprintCallable)
+	float GetMaxHealth() const	{ return MaxHealth; }
+
+	FORCEINLINE USoundCue* GetMeleeImpactSound() const { return MeleeImpactSound; }
 };