[UE4]FPS Project-7 (AI Enemy)

1. AI

• .h

  UPROPERTY(VisibleDefaultsOnly, Category = Enemy)
  			class UAIPerceptionComponent* AIPerComp;
  UPROPERTY(VisibleDefaultsOnly, Category = Enemy)
  			class UAISenseConfig_Sight* SightConfig;
  UFUNCTION()
  			void OnSensed(const TArray<AActor*>& UpdatedActors);

• .cpp : 생성자

    AIPerComp = CreateDefaultSubobject<UAIPerceptionComponent>(TEXT("AI Perception Component"));
  		SightConfig = CreateDefaultSubobject<UAISenseConfig_Sight>(TEXT("Sight Config"));
  
  		SightConfig->SightRadius = 1250.0f; // 시각 반경
  		SightConfig->LoseSightRadius = 1280.0f; // 시각 상실 반경
  		SightConfig->PeripheralVisionAngleDegrees = 90.0f; // 주변 시야각
  		SightConfig->DetectionByAffiliation.bDetectEnemies = true; // 소속별 탐지 적
  		SightConfig->DetectionByAffiliation.bDetectFriendlies = true; // 소속별 탐지 팀
  		SightConfig->DetectionByAffiliation.bDetectNeutrals = true; // 소속별 탐지 중립
  		SightConfig->SetMaxAge(0.1f); //자극이 잊히기 까지의 시간 (0이면 잊지않음)
  
  		AIPerComp->ConfigureSense(*SightConfig);
  		AIPerComp->SetDominantSense(SightConfig->GetSenseImplementation());
  		AIPerComp->OnPerceptionUpdated.AddDynamic(this, &AEnemy::OnSensed);

2. Movement

• 주인공을 보면 따라가고 시야에서 벗어나면 다시 제 위치로 돌아옴

• .h

    PROPERTY(VisibleAnywhere, Category = Movement)
  			FRotator EnemyRotation;
  
  		UPROPERTY(VisibleAnywhere, Category = Movement)
  			FVector BaseLocation;
  
  		UPROPERTY(VisibleAnywhere, BlueprintReadOnly, Category = Movement)
  			FVector CurrentVelocity;
  
  		UPROPERTY(VisibleAnywhere, Category = Movement)
  			float MovementSpeed;
  
  		void SetNewRotation(FVector TargetPosition, FVector CurrentPosition);
  
  		bool BackToBaseLocation;
  		FVector NewLocation;
  		float DistanceSquared;

• .cpp : 생성자

    CurrentVelocity = FVector::ZeroVector;
  		MovementSpeed = 375.0f;
  
  		DistanceSquared = BIG_NUMBER; //32bit 부동 소수점의 최대값

• .cpp : BeginStart()

  BaseLocation = this->GetActorLocation();

• .cpp : SetNewRotation()

  • Enemy가 Character를 바라보도록 설정

    FVector NewDirection = TargetPosition - CurrentPosition;
  		NewDirection.Z = 0.0f;
  
  		EnemyRotation = NewDirection.Rotation();
  
  		SetActorRotation(EnemyRotation);

• .cpp : OnSensed

  • Character가 보이면 그 방향으로 이동
  • 보이지 않으면 원래 방향으로 이동

    for (int i = 0; i < UpdatedActors.Num(); i++)
  		{
  			FActorPerceptionBlueprintInfo Info;
  			AIPerComp->GetActorsPerception(UpdatedActors[i], Info);
  
  			if (Info.LastSensedStimuli[0].WasSuccessfullySensed())
  			{
  				FVector dir = UpdatedActors[i]->GetActorLocation() - GetActorLocation();
  				dir.Z = 0.0f;
  
  				CurrentVelocity = dir.GetSafeNormal() * MovementSpeed;
  
  				SetNewRotation(UpdatedActors[i]->GetActorLocation(), GetActorLocation());
  			}
  			else
  			{
  				FVector dir = BaseLocation - GetActorLocation();
  				dir.Z = 0.0f;
  
  				if (dir.SizeSquared2D() > 1.0f)
  				{
  					CurrentVelocity = dir.GetSafeNormal() * MovementSpeed;
  					BackToBaseLocation = true;
  
  					SetNewRotation(BaseLocation, GetActorLocation());
  				}
  			}

• .cpp : Tick()

  • NewLocation 갱신

      if (!CurrentVelocity.IsZero())
      {
  			NewLocation = GetActorLocation() + CurrentVelocity * DeltaTime;
  
  			if (BackToBaseLocation)
  			{
  				if ((NewLocation - BaseLocation).SizeSquared2D() < DistanceSquared)
  				{
  					DistanceSquared = (NewLocation - BaseLocation).SizeSquared2D();
  				}
  				else
  				{
  					CurrentVelocity = FVector::ZeroVector;
  					DistanceSquared = BIG_NUMBER;
  					BackToBaseLocation = false;
  
  					SetNewRotation(GetActorForwardVector(), GetActorLocation());
  				}
  			}
  
  			SetActorLocation(NewLocation);
  		}