世界交互 - 飞弹

• 将精灵拖放到 Hierarchy 窗口中。

Rigidbody2D rigidbody2d;
    
void Start()
{
    rigidbody2d = GetComponent<Rigidbody2D>();
}

public void Launch(Vector2 direction, float force)
{
    rigidbody2d.AddForce(direction * force);
}

void OnCollisionEnter2D(Collision2D other)
{
    //我们还增加了调试日志来了解飞弹触碰到的对象
    Debug.Log("Projectile Collision with " + other.gameObject);
    Destroy(gameObject);
}

void Launch()
{
    GameObject projectileObject = Instantiate(projectilePrefab, rigidbody2d.position + Vector2.up * 0.5f, Quaternion.identity);

    Projectile projectile = projectileObject.GetComponent<Projectile>();
    projectile.Launch(lookDirection, 300);

    animator.SetTrigger("Launch");
}

if(Input.GetKeyDown(KeyCode.C))
{
   Launch();
}

void Update()
{
	//注意，! 符号可以反转测试，因此，如果 broken 为 true，则 !broken 将为 false，并且不会执行 return。
if(!broken)
{
    return;
}

void FixedUpdate()
{
  if(!broken)
  {
      return;
  }

//使用 public 的原因是我们希望像飞弹脚本一样在其他地方调用这个函数
public void Fix()
{
    broken = false;
    rigidbody2D.simulated = false;
}

void OnCollisionEnter2D(Collision2D other)
{
    EnemyController e = other.collider.GetComponent<EnemyController>();
    if (e != null)
    {
        e.Fix();
    }
    
    Destroy(gameObject);
}

void Update()
{
    if(transform.position.magnitude > 1000.0f)
    {
        Destroy(gameObject);
    }
}

这个步骤是可选步骤，因为不会为游戏添加功能，并且与飞弹无关，但可以使游戏更美观。

你将为修好的机器人添加动画。请参阅上一教程，了解有关如何创建动画和使用 Animator 的更多详细信息。

1.为敌人创建一段新的动画剪辑（使用 MrClockworkFixed 帧 1、2、3 和 4），命名为 RobotFixed。别忘了把 Sample 设置成 4。

2.在 Enemy Animator 中，创建从正在运行的“混合树”到这段新动画的过渡。别忘了禁用 Has Exit Time。无需进行反向的过渡，因为机器人在修好后，就一直保持修复状态。

3.创建类型为 Trigger 且名为 Fixed 的参数，并将此参数设置为过渡条件：

选择要展开的图像

输入图像描述 (可选)

现在，在 Enemy 脚本的 Fix 函数中，只需添加以下代码行：

animator.SetTrigger("Fixed");

public class RubyController : MonoBehaviour
{
    public float speed = 3.0f;
    
    public int maxHealth = 5;
    
    public GameObject projectilePrefab;
    
    public int health { get { return currentHealth; }}
    int currentHealth;
    
    public float timeInvincible = 2.0f;
    bool isInvincible;
    float invincibleTimer;
    
    Rigidbody2D rigidbody2d;
    float horizontal;
    float vertical;
    
    Animator animator;
    Vector2 lookDirection = new Vector2(1,0);
    
    // 在第一次帧更新之前调用 Start
    void Start()
    {
        rigidbody2d = GetComponent<Rigidbody2D>();
        animator = GetComponent<Animator>();
        
        currentHealth = maxHealth;
    }

    // 每帧调用一次 Update
    void Update()
    {
        horizontal = Input.GetAxis("Horizontal");
        vertical = Input.GetAxis("Vertical");
        
        Vector2 move = new Vector2(horizontal, vertical);
        
        if(!Mathf.Approximately(move.x, 0.0f) || !Mathf.Approximately(move.y, 0.0f))
        {
            lookDirection.Set(move.x, move.y);
            lookDirection.Normalize();
        }
        
        animator.SetFloat("Look X", lookDirection.x);
        animator.SetFloat("Look Y", lookDirection.y);
        animator.SetFloat("Speed", move.magnitude);
        
        if (isInvincible)
        {
            invincibleTimer -= Time.deltaTime;
            if (invincibleTimer < 0)
                isInvincible = false;
        }
        
        if(Input.GetKeyDown(KeyCode.C))
        {
            Launch();
        }
    }
    
    void FixedUpdate()
    {
        Vector2 position = rigidbody2d.position;
        position.x = position.x + speed * horizontal * Time.deltaTime;
        position.y = position.y + speed * vertical * Time.deltaTime;

        rigidbody2d.MovePosition(position);
    }

    public void ChangeHealth(int amount)
    {
        if (amount < 0)
        {
            if (isInvincible)
                return;
            
            isInvincible = true;
            invincibleTimer = timeInvincible;
        }
        
        currentHealth = Mathf.Clamp(currentHealth + amount, 0, maxHealth);
        Debug.Log(currentHealth + "/" + maxHealth);
    }
    
    void Launch()
    {
        GameObject projectileObject = Instantiate(projectilePrefab, rigidbody2d.position + Vector2.up * 0.5f, Quaternion.identity);

        Projectile projectile = projectileObject.GetComponent<Projectile>();
        projectile.Launch(lookDirection, 300);

        animator.SetTrigger("Launch");
    }
}

public class EnemyController : MonoBehaviour
{
    public float speed;
    public bool vertical;
    public float changeTime = 3.0f;

    Rigidbody2D rigidbody2D;
    float timer;
    int direction = 1;
    bool broken = true;
    
    Animator animator;
    
    // 在第一次帧更新之前调用 Start
    void Start()
    {
        rigidbody2D = GetComponent<Rigidbody2D>();
        timer = changeTime;
        animator = GetComponent<Animator>();
    }

    void Update()
    {
        //注意，! 符号可以反转测试，因此，如果 broken 为 true，则 !broken 将为 false，并且不会执行 return。
        if(!broken)
        {
            return;
        }
        
        timer -= Time.deltaTime;

        if (timer < 0)
        {
            direction = -direction;
            timer = changeTime;
        }
    }
    
    void FixedUpdate()
    {
        //注意，! 符号可以反转测试，因此，如果 broken 为 true，则 !broken 将为 false，并且不会执行 return。
        if(!broken)
        {
            return;
        }
        
        Vector2 position = rigidbody2D.position;
        
        if (vertical)
        {
            position.y = position.y + Time.deltaTime * speed * direction;
            animator.SetFloat("Move X", 0);
            animator.SetFloat("Move Y", direction);
        }
        else
        {
            position.x = position.x + Time.deltaTime * speed * direction;
            animator.SetFloat("Move X", direction);
            animator.SetFloat("Move Y", 0);
        }
        
        rigidbody2D.MovePosition(position);
    }
    
    void OnCollisionEnter2D(Collision2D other)
    {
        RubyController player = other.gameObject.GetComponent<RubyController >();

        if (player != null)
        {
            player.ChangeHealth(-1);
        }
    }
    
    //使用 public 的原因是我们希望像飞弹脚本一样在其他地方调用这个函数
    public void Fix()
    {
        broken = false;
        rigidbody2D.simulated = false;
        //如果你添加了修复动画，则为可选
        animator.SetTrigger("Fixed");
    }
}

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class Projectile : MonoBehaviour
{
    Rigidbody2D rigidbody2d;
    
    void Awake()
    {
        rigidbody2d = GetComponent<Rigidbody2D>();
    }
    
    public void Launch(Vector2 direction, float force)
    {
        rigidbody2d.AddForce(direction * force);
    }
    
    void Update()
    {
        if(transform.position.magnitude > 1000.0f)
        {
            Destroy(gameObject);
        }
    }
    
    void OnCollisionEnter2D(Collision2D other)
    {
        EnemyController e = other.collider.GetComponent<EnemyController>();
        if (e != null)
        {
            e.Fix();
        }
    
        Destroy(gameObject);
    }
}