让敌人在 Unity 中向玩家加速

Question

我有一个脚本让敌人以相同的速度向玩家移动，但我试图让敌人在切换方向时减速然后加速。敌人目前只是向左移动并写向玩家的位置。 这是我老板在更新函数中附加的脚本中的代码：

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

我也尝试过使用 Lerp 并使用 transform.position 作为第一个参数，但是当玩家靠近时，boss 会变慢，当玩家远离时会变快。

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

有没有人知道如何让敌人减速，然后在他改变方向时逐渐增加速度，然后在他改变方向后恢复正常速度

**编辑：**下面的完整脚本

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

要获得位置（米/秒），您需要乘以速度 * Time.deltatime，从而获得米。要处理加速度，您需要处理可变速度。加速度是 m/s2，乘以 * Time.deltatime 您将获得即时速度，而该速度 * Time.deltaTime 将为您提供位置。

这里有一些伪代码（step 和 speed 应该是类变量，并且在更新中进行了修改。accel 是恒定的加速度，为了简单起见应该是常量，我猜你需要均匀加速的运动）：

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

使用加速度 + 或 - 的符号，您将确定实体的速度是增加（加速）还是减少（减速）。

希望有帮助

编辑：

完整脚本：

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);
  }
}

编辑器中附加的脚本屏幕截图：

将脚本附加到要移动的游戏对象上，并在公共字段中附加目标的变换。选择你的加速度，正向加速，负向加速，然后你就明白了。