daluandou/Assets/Script/EnemyBaseMove.cs

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

public class NewBehaviourScript : MonoBehaviour
{

    //移动速度
    public float speed = 5f;

    //重力加速度
    public float gravity = -20f;

    //活动范围
    public float range = 500f;

    //侦查范围
    public float detectRange = 200f;

    //攻击范围
    public float attackRange = 5f;

    //角色状态
    private State state = State.Alert;

    //攻击目标
    public GameObject target;

    //当前目标点
    private Vector3 targetPos;

    //初始位置坐标
    private Vector3 startPos;

    //动画控制器
    private Animator animator;

    // 角色控制器
    private CharacterController controller;

    //垂直速度
    private float verticalVelocity;

    //状态枚举
    public enum State
    {
        //警戒巡逻
        Alert,

        //追踪状态
        Track, 

        //攻击状态
        Attack
    }






    // Start is called before the first frame update
    void Start()
    {
        //初始化
        animator = GetComponent<Animator>();
        controller = GetComponent<CharacterController>();
        //记录初始坐标
        startPos = transform.position;
        randomTargetPos();
    }



    // Update is called once per frame
    void Update()
    {
        //攻击状态直接返回
        if (state == State.Attack)
        {
            animator.SetInteger("speed", 0);
            applyGravity();
            return;
        }

        //获取侦查范围内除自己以外的Player层的单位
        var players = Physics.OverlapSphere(transform.position, detectRange, LayerMask.GetMask("Player"));
        //如果存在单位
        if (players.Length > 0)
        {
            //找出标签是Friend的,并且不是自己
            foreach (var player in players)
            {
                if (player.tag == "Friend" && player != gameObject)
                {
                    //进入追逐状态
                    state = State.Track;
                    float dis = Vector3.Distance(transform.position, player.transform.position);
                    //和目标的距离在攻击范围外则朝目标移动
                    if (dis > attackRange)
                    {
                        move(player.transform.position - transform.position);
                        //打印动画speed的值
                        Debug.Log(animator.GetInteger("speed"));
                    }
                    else
                    {
                        attack(player);
                    }
                    return;
                }
            }
        }

        if (state == State.Track)
        {
            state = State.Alert;
        }

        //没有侦查到敌人则回到巡逻
        state = State.Alert;
        //角色在攻击状态则返回
        if (state == State.Alert)
        {
            //移动
            move(targetPos - transform.position);
            //到达目标点时候随机目标点，只判断水平距离
            Vector3 patrolOffset = transform.position - targetPos;
            patrolOffset.y = 0;
            if (patrolOffset.sqrMagnitude < 0.01f)
            {
                randomTargetPos();
            }
        }


    }

    //攻击
    private void attack(Collider player)
    {
        //转向攻击目标
        var direction = player.transform.position - transform.position;
        direction.y = 0;
        if (direction != Vector3.zero)
        {
            transform.rotation = Quaternion.LookRotation(direction, Vector3.up);
        }
        //攻击动画动作
        animator.SetInteger("speed", 0);
        animator.SetTrigger("attack");
        state = State.Attack;
    }


    // 在 Animator 的 Attack 动画结束时调用此方法
    public void OnAttackAnimationEnd()
    {
        //打印
        Debug.Log("攻击结束");
        state = State.Alert;
        randomTargetPos();
    }



    //角色移动,持续到目标点
    void move(Vector3 movement)
    {
        movement.y = 0;
        if (movement == Vector3.zero)
        {
            animator.SetInteger("speed", 0);
            applyGravity();
            return;
        }

        //改变动画控制器的参数
        animator.SetInteger("speed", 1);
        //向目标点移动，同时应用垂直重力
        Vector3 velocity = movement.normalized * speed;
        velocity.y = getVerticalVelocity();
        controller.Move(velocity * Time.deltaTime);
        //改变角色朝向目标点,只改变y轴
        transform.rotation = Quaternion.LookRotation(movement, Vector3.up);
        transform.rotation = Quaternion.Euler(0, transform.rotation.eulerAngles.y, 0);
    }


    private float getVerticalVelocity()
    {
        if (controller.isGrounded && verticalVelocity < 0)
        {
            verticalVelocity = -2f;
        }
        else
        {
            verticalVelocity += gravity * Time.deltaTime;
        }

        return verticalVelocity;
    }

    private void applyGravity()
    {
        controller.Move(Vector3.up * getVerticalVelocity() * Time.deltaTime);
    }

    //随机目标点
    private void randomTargetPos()
    {
        //以startPos为中心，在水平圆形范围内随机一个点
        Vector2 randomOffset = Random.insideUnitCircle * range;
        targetPos = startPos + new Vector3(randomOffset.x, 0, randomOffset.y);
    }
}