讓敵人在 Unity 中向玩家加速

Question

我有一個腳本讓敵人以相同的速度向玩家移動，但我試圖讓敵人在切換方向時減速然后加速。 敵人目前只是向左移動並寫向玩家的 position。 這是我的老板在更新 function 中附加的腳本中的代碼：

Vector2 targetPosition = new Vector2 (player.transform.position.x, transform.position.y); 
transform.position = Vector2.MoveTowards (transform.position, targetPosition, moveSpeed * Time.deltaTime);

我也嘗試過使用 Lerp 並使用 transform.position 作為第一個參數，但是當玩家靠近時，boss 會變慢，當玩家遠離時會變快。

transform.position = Vector2.Lerp (transform.position, targetPosition, moveSpeed * Time.deltaTime);

有沒有人知道如何讓敵人減速，然后在他改變方向時逐漸增加速度，然后在他改變方向后恢復正常速度

**編輯：**下面的完整腳本

using UnityEngine;

public class Roll : StateMachineBehaviour
{
    [SerializeField] private float moveSpeed = 2.4f; 
    [SerializeField] private float rotateSpeed = 100f; 

    [SerializeField] private float minRollTime = 6f;
    [SerializeField] private float maxRollTime = 8f;
    private float rollTimer = 0f; 

    [SerializeField] private float rightBoundary = 5f;
    [SerializeField] private float leftBoundary = -5f;

    private Transform playerTransform = null;
    private BossHealth bossHealth = null;     
    private Transform bossTransform = null;
    private Transform bodyTransform = null;
    private Transform earsTransform = null; 

    private Vector2 targetPosition = Vector2.zero; 

    override public void OnStateEnter(Animator animator, AnimatorStateInfo stateInfo, int layerIndex)
    {
        playerTransform = GameObject.FindWithTag("Player").transform; 

        bossHealth = animator.GetComponent<BossHealth>(); 

        Boss01 boss = FindObjectOfType<Boss01>(); 
        bossTransform = boss.bossTransform;  
        bodyTransform = boss.bodyTransform; 
        earsTransform = boss.earsTransform; 

        rollTimer = Random.Range (minRollTime, maxRollTime); 
    }

    override public void OnStateUpdate(Animator animator, AnimatorStateInfo stateInfo, int layerIndex)
    {
        if (bossTransform.position.x >= leftBoundary && bossTransform.position.x <= rightBoundary)
        {
            targetPosition = new Vector2(playerTransform.position.x, bossTransform.position.y);
            bossTransform.position = Vector2.MoveTowards(bossTransform.position, targetPosition, moveSpeed * Time.deltaTime);

            if (playerTransform.position.x > 0)
                bodyTransform.Rotate(0f, 0f, -rotateSpeed * Time.deltaTime); 
            else
                bodyTransform.Rotate(0f, 0f, rotateSpeed * Time.deltaTime); 
        }
        else if (bossTransform.position.x < leftBoundary) 
        {
            if (playerTransform.position.x > bossTransform.position.x) 
            {
                targetPosition = new Vector2(playerTransform.position.x, bossTransform.position.y);
                bossTransform.position = Vector2.MoveTowards(bossTransform.position, targetPosition, moveSpeed * Time.deltaTime);
            }
        }
        else
        {
            if (playerTransform.position.x < bossTransform.position.x) 
            {
                targetPosition = new Vector2(playerTransform.position.x, bossTransform.position.y);
                bossTransform.position = Vector2.MoveTowards(bossTransform.position, targetPosition, moveSpeed * Time.deltaTime);
            }
        }

        if (rollTimer <= 0f)
            animator.SetTrigger ("aim"); 
        else
            rollTimer -= Time.deltaTime; 

        if (bossHealth.CheckHealth())
            animator.SetTrigger ("transition"); 

        if (earsTransform.rotation != Quaternion.Euler (0f, 0f, 0f))
            earsTransform.rotation = Quaternion.Slerp(earsTransform.rotation, Quaternion.Euler(0f, 0f, 0f), 1f * Time.deltaTime); 
    }

    override public void OnStateExit(Animator animator, AnimatorStateInfo stateInfo, int layerIndex)
    {
        animator.ResetTrigger ("aim"); 
        animator.ResetTrigger ("transition"); 
    }
}

Answer 1

要實現 position（米/秒），您需要乘以速度 * Time.deltatime，從而獲得米。 要處理加速度，您需要處理可變速度。 加速度為 m/s2，乘以 * Time.deltatime，您將獲得即時速度，而該速度 * Time.deltaTime 將為您提供 position。

這里有一些偽代碼（步長和速度應該是 class 變量，並且在更新中進行了修改。加速是恆定的加速度，為了簡單起見應該是常數，我猜你需要均勻加速的運動）：

speed += accel * Time.deltaTime; // instant speed
step =  speed * Time.deltaTime; // calculate distance to move
transform.position = Vector3.MoveTowards(transform.position, target.position, step);

使用加速 + 或 - 的符號，您將確定實體速度是增加（加速）還是減少（減速）。

希望有幫助

編輯：

完整腳本：

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

public class MoveTowards : MonoBehaviour
{
  public Transform target;
  private float step = 0f;
  private float speed = 0f;
  public float accel = 0f;
  // Start is called before the first frame update
  void Start()
  {

  }

  // Update is called once per frame
  void Update()
  {
    speed += accel * Time.deltaTime; // instant speed
    step = speed * Time.deltaTime; // calculate distance to move
    transform.position = Vector3.MoveTowards(transform.position, target.position, step);
  }
}

編輯器中附加的腳本截圖：

將腳本附加到您要移動的游戲 object 中，並在公共字段中附加目標的變換。 選擇你的加速度，正向加速，負向加速，然后你就明白了。