1 using UnityEngine;
 2 using System.Collections;
 3 public class VectorCrossDemo : MonoBehaviour 
 4 {
 5 private GameObject wheelObj;
 6 private Vector3 wheelPos = Vector3.zero; 
 7 private Vector3 oldVec = Vector3.zero;
 8 private Vector3 currVec = Vector3.zero;
 9 // Use this for initialization
10 void Start () 
11 {
12 wheelObj = GameObject.Find("Wheel");
13 if(null != wheelObj)
14 {
15 wheelPos = wheelObj.transform.position;
16 }
17 }
18  
19 // Update is called once per frame
20 void Update () 
21 {
22 if (Input.GetMouseButton(0))
23 {
24 var ray = Camera.main.ScreenPointToRay(Input.mousePosition);
25 RaycastHit hit;
26 if (Physics.Raycast(ray, out hit)) 
27 {
28 if(hit.transform.name.Equals("Wheel"))
29 {
30 RotateWheel(hit.point);
31 }
32 }
33 }
34 }
35 void RotateWheel (Vector3 pos)
36 {
37 currVec = pos - wheelPos;//计算方向盘中心点到触控点的向量        
38 Vector3 normalVec = Vector3.Cross(currVec, oldVec);//计算法向量
39 float vecAngle = Vector2.Angle(currVec, oldVec);//计算两个向量的夹角        
40 // 使用“右手定则”可知，当大拇指方向指向我们，四指方向为逆时针方向；
41 // 当大拇指远离我们，四指方向为顺时针方向。
42 // 这里叉乘后的法向量平行于z轴,所以用法向量的z分量的正负判断法向量方向
43 if (normalVec.z > 0)// 和z轴同向，则顺时针转
44 {
45 wheelObj.transform.Rotate(Vector3.forward, -vecAngle);// 顺时针转
46 }
47 else if (normalVec.z < 0)//和z轴反向，则逆时针转
48 {
49 wheelObj.transform.Rotate(Vector3.forward, vecAngle);// 逆时针转
50 }
51 oldVec = currVec;//赋值
52 }
53 }

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

public class AniSubGun : ArchAnimation
{
    //1.首先我得旋转到我指定的目标点
    //2.控制旋转的角度
    //3.判断目标是否在我的攻击范围之内
    //4.判断是否在我的扇形攻击范围角度之内
    //5. 
    //// 通过向量直接获取两个向量的夹角（默认为 角度）， 此方法范围 [0 - 180]  
    //float angle = Vector3.Angle(a, b);
    //这两个算法是一样的
    //// 计算 a、b 点积结果  
    //float result = Vector3.Dot(a, b);
    //// 计算 a、b 单位向量的点积,得到夹角余弦值,|a.normalized|*|b.normalized|=1;  
    //result = Vector3.Dot(a.normalized, b.normalized);
    //// 通过反余弦函数获取 向量 a、b 夹角（默认为 弧度）  
    //float radians = Mathf.Acos(result);
    //// 将弧度转换为 角度  
    //angle = radians * Mathf.Rad2Deg;

    public const int ANI_SEARCH = 0;

    protected static float m_AniSpeed = 2f;
    protected static float m_MaxAngle = 120f;
    protected static float m_MinRanger = 0f;
    protected static float m_MaxRanger = 1500f;

    protected FightTarg m_AttackTarg = null;
    protected Vector3 m_NormalizedVec = Vector3.zero;

    public delegate void ArmAtEnemyEvent(bool bFire);
    protected ArmAtEnemyEvent OnArmAtEnemy;
    protected override void Awake()
    {
        base.Awake();
    }
    protected override void Start()
    { 
        base.Start();
    }
    protected override void Update()
    {
        base.Update(); 
        ArmAtTarg(); 
    } 
    protected override void OnDestroy()
    {
        base.OnDestroy(); 
    }
    public void SetAttackTarg(FightTarg itarg)
    {
        m_AttackTarg = itarg;
    }
    private void ArmAtTarg()
    {
        if (m_NormalizedVec == null || m_AttackTarg == null || m_AttackTarg.IsDie())
        {
            DoCallbackArmAtEnemy(false);
            m_AttackTarg = null;
            return;
        }
        Vector3 myV3 = m_go.transform.rotation * Vector3.forward; ;
        Vector3 npcV3 = m_AttackTarg.getHitGameObject().transform.position - m_go.transform.position;//敌人和我的向量

        npcV3.y = myV3.y;

        float RangleAngle = Mathf.Abs(Vector3.Angle(m_NormalizedVec, npcV3));//NPC和法向量的夹角（0-180）

        float RotationAngle1 = Mathf.Abs(Vector3.Angle(myV3, npcV3)); //炮和NPC的夹角（0-180） 
        float Distance = npcV3.magnitude;//NPC和我的距离 

        Vector3 CrossNorNpc = Vector3.Cross(m_NormalizedVec, npcV3);
        Vector3 CrossNorMe = Vector3.Cross(m_NormalizedVec, myV3);
        Vector3 CrossMeNpc = Vector3.Cross(myV3, npcV3);
        Vector3 CrossMeNor = Vector3.Cross(myV3, m_NormalizedVec); 

        float RotationAngle2 = Mathf.Abs(Vector3.Angle(myV3, m_NormalizedVec)); //炮和法向量的夹角（0-180）

        //Debug.LogError("AniAirArtilleryBase::RotationCent()和法向量的夹角:" + RangleAngle
        //    + ",NPC的夹角:" + RotationAngle1 + ",NPC距离:" + Distance + ",旋转方向:" + CrossMeNpc.y);

        if (RangleAngle > m_MaxAngle || Distance > m_MaxRanger || Distance < m_MinRanger)
        {
            DoCallbackArmAtEnemy(false);
            return;
        }

        float sidesign = CrossNorNpc.y * CrossNorMe.y;
        float rotation = 0;
        if (sidesign < 0 && RotationAngle2>10)
        {
            //我和NPC不在法向量的同一边，则先往法向量方向旋转
            //角度为炮和NPC的旋转夹角(大于等于RotationAngle1)
            rotation = (RangleAngle + RotationAngle2);
            if (CrossMeNor.y < 0)
                rotation = 0 - rotation; 
        }  
        else
        {
            rotation = RotationAngle1;
            if (CrossMeNpc.y < 0)
                rotation = 0 - RotationAngle1; 
        }
        if (Mathf.Abs(rotation) > 0.8)
            rotation = rotation * Time.deltaTime * m_AniSpeed; 
        m_go.transform.localEulerAngles += new Vector3(0, rotation, 0); 

        //可以发射子弹了
        DoCallbackArmAtEnemy(true);
    }
    private void DoCallbackArmAtEnemy(bool bArmAt)
    {
        if (OnArmAtEnemy == null)
            return;
        OnArmAtEnemy(bArmAt);
    }
    public void RegisterOnArm(ArmAtEnemyEvent _callback)
    {
        OnArmAtEnemy -= _callback;
        OnArmAtEnemy += _callback;
    }
    public void UnRegisterOnArm(ArmAtEnemyEvent _callback)
    {
        OnArmAtEnemy -= _callback;
    }  
}