멋쟁이 사자처럼 부트캠프 유니티 게임 개발 4기 30일차 회고

💻 Unity

2D Raycast

isGrounded = Physics2D.Raycast(groundCheck.position, Vector2.down, groundCheckDistance, whatIsGround);

void OnDrawGizmos()
{
    Gizmos.DrawLine(groundCheck.position, new Vector3(groundCheck.position.x, groundCheck.position.y - groundCheckDistance));
}

groundCheck 위치에서 플레이어의 아래쪽(Vector2.down)으로 groundCheckDistance만큼 레이캐스트를 쏴서 땅이 있는지 확인

isWallDetected = Physics2D.Raycast(wallCheck.position, Vector2.right, wallCheckDistance * facingDir, whatIsGround);

void OnDrawGizmos()
{
    Gizmos.DrawLine(wallCheck.position, new Vector3(wallCheck.position.x + wallCheckDistance * facingDir, wallCheck.position.y));
}

wallCheck 위치에서 **바라보는 방향(facingDir)**으로 wallCheckDistance만큼 레이캐스트를 쏴서 벽이 있는지 확인

🕹️ 실습 (2D 횡스크롤 2)

Entity와 상속으로 Player, Enemy 구현

public class Entity : MonoBehaviour
{
    protected Animator animator;
    protected Rigidbody2D rb;

    protected int facingDir = 1;
    protected bool isFacingRight = true;

    [Header("Collision Info")]
    [SerializeField]
    protected Transform groundCheck;
    [SerializeField]
    protected float groundCheckDistance;
    [Space]
    [SerializeField]
    protected Transform wallCheck;
    [SerializeField]
    protected float wallCheckDistance;
    [Space]
    [SerializeField]
    private LayerMask whatIsGround;

    protected bool isGrounded;
    protected bool isWallDetected;

    protected virtual void Start()
    {
        animator = GetComponentInChildren<Animator>();
        rb = GetComponent<Rigidbody2D>();
    }

    protected virtual void Update()
    {
        CheckCollision();
    }

    protected virtual void Flip()
    {
        facingDir = facingDir * -1;
        isFacingRight = !isFacingRight;
        transform.Rotate(0, 180, 0);
    }

    protected virtual void CheckCollision()
    {
        isGrounded = Physics2D.Raycast(groundCheck.position, Vector2.down, groundCheckDistance, whatIsGround);
        isWallDetected = Physics2D.Raycast(wallCheck.position, Vector2.right, wallCheckDistance * facingDir, whatIsGround);
    }

    protected virtual void OnDrawGizmos()
    {
        Gizmos.DrawLine(groundCheck.position, new Vector3(groundCheck.position.x, groundCheck.position.y - groundCheckDistance));
        Gizmos.DrawLine(wallCheck.position, new Vector3(wallCheck.position.x + wallCheckDistance * facingDir, wallCheck.position.y));
    }
}

public class EnemySkeleton : Entity
{
    bool isAttacking;

    [Header("Move Info")]
    [SerializeField]
    private float moveSpeed;

    [Header("Player Derection")]
    [SerializeField]
    private float playerCheckDistance;
    [SerializeField]
    private LayerMask whatIsPlayer;

    private RaycastHit2D isPlayerDetected;

    protected override void Start()
    {
        base.Start();
    }

    protected override void Update()
    {
        base.Update();

        MoveEnemySkeleton();
        HandlePlayerDerection();
    }

    protected override void CheckCollision()
    {
        base.CheckCollision();
        isPlayerDetected = Physics2D.Raycast(transform.position, Vector2.right, playerCheckDistance * facingDir, whatIsPlayer);

        if (!isGrounded || isWallDetected)
        {
            Flip();
        }
    }

    private void MoveEnemySkeleton()
    {
        if (!isAttacking)
        {
            rb.linearVelocity = new Vector2(moveSpeed * facingDir, rb.linearVelocityY);
        }
    }

    private void HandlePlayerDerection()
    {
        if (!isAttacking)
        {
            rb.linearVelocity = new Vector2(moveSpeed * facingDir, rb.linearVelocityY);
        }

        if (isPlayerDetected)
        {
            if (isPlayerDetected.distance > 1)
            {
                // 추적
                rb.linearVelocity = new Vector2(moveSpeed * 1.5f * facingDir, rb.linearVelocityY);
                isAttacking = false;
                Debug.Log("Enemy : 플레이어 감지");
            }
            else
            {
                isAttacking = true;
                Debug.Log($"Enemy : 공격! {isPlayerDetected.collider.gameObject.name}");
            }
        }
    }

    protected override void OnDrawGizmos()
    {
        base.OnDrawGizmos();
        Gizmos.color = Color.blue;
        Gizmos.DrawLine(transform.position, new Vector3(transform.position.x + playerCheckDistance * facingDir, transform.position.y));
    }
}

🕹️ 실습 (2D 횡스크롤 3)

StateMachine으로 Player 구현

public class PlayerState
{
    protected Player player;
    protected PlayerStateMchine stateMachine;

    private string animationBoolName;

    public PlayerState(Player _player, PlayerStateMchine _stateMachine, string _animationBoolName)
    {
        player = _player;
        stateMachine = _stateMachine;
        animationBoolName = _animationBoolName;
    }

    public virtual void Enter()
    {
        Debug.Log($"Enter - {animationBoolName}");
    }

    public virtual void Update()
    {
        Debug.Log($"Update - {animationBoolName}");
    }

    public virtual void Exit()
    {
        Debug.Log($"Exit - {animationBoolName}");
    }
}

public class PlayerStateMchine
{
    public PlayerState currentState { get; private set; }

    public void Initialize(PlayerState startState)
    {
        currentState = startState;
        currentState.Enter();
    }

    public void ChangeState(PlayerState newState)
    {
        currentState.Exit();
        currentState = newState;
        currentState.Enter();
    }
}

public class PlayerIdleState : PlayerState
{
    public PlayerIdleState(Player _player, PlayerStateMchine _stateMachine, string _animationBoolName)
        : base(_player, _stateMachine, _animationBoolName)
    {

    }

    public override void Enter()
    {
        base.Enter();
    }

    public override void Update()
    {
        base.Update();

        if (Input.GetKeyDown(KeyCode.N))
        {
            player.stateMachine.ChangeState(player.moveState);
        }
    }

    public override void Exit()
    {
        base.Exit();
    }
}

public class Player : MonoBehaviour
{
    public PlayerStateMchine stateMachine { get; private set; }
    
    public PlayerIdleState idleState { get; private set; }
    public PlayerMoveState moveState { get; private set; }

    private void Awake()
    {
        stateMachine = new PlayerStateMchine();

        idleState = new PlayerIdleState(this, stateMachine, "Idle");
        moveState = new PlayerMoveState(this, stateMachine, "Move");
    }

    private void Start()
    {
        stateMachine.Initialize(idleState);
    }

    private void Update()
    {
        stateMachine.currentState.Update();
    }
}

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📝 과제

스테이트 머신 구현