Unity-UGUI多点触控、多点滑动摇杆操作

现在很多手游都是通过摇杆操作：

1. 比如左手摇杆，右手点击按钮攻击的MMO系列；
2. 或者是左右手都有类似摇杆拖动设计的按钮（王者荣耀：左手摇杆右手点击或者拖动技能方向。）
3. 比如左手摇杆控制移动，右手开枪，开枪的同时开支持那个手指滑动瞄准（类似吃鸡的操作）。
4. 比如左手大拇指控制摇杆移动，左手食指点击吃药，右手大拇指控制攻击，右手食指控制滑动，右手小手指负责扣脚（没有这个游戏）
   等等。。。。

具体设计思路：

image.png

代码：

代码分两个脚本：
一个负责监听整个场景的所有触摸事件：TouchManager
一个负责单独添加到想要实现各种操作的摇杆按钮（图片）上: joySticButton（是否屏蔽下层事件需要在Inspector上设置）

TouchManager：

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

public class TouchManager : MonoBehaviour
{
    private static TouchManager instance = null;
    private Dictionary<int, List<JoyStickButton>> dicJoyStick;
    
    public static TouchManager getInstant()
    {
        return instance;
    }
    // Start is called before the first frame update
    void Start()
    {
        dicJoyStick = new Dictionary<int, List<JoyStickButton>>();
    }
    private void Awake()
    {
        if(instance == null)
        {
            instance = this;
        }
        else
        {
            Destroy(this);
        }
    }

    // Update is called once per frame
    void Update()
    {
        for(int i = 0; i < Input.touchCount; ++i)
        {
            Touch touch = Input.GetTouch(i);
            if(touch.phase == TouchPhase.Began)
            {
                this.checkAndRegist(touch.fingerId, touch.position);
                this.callTouchBegan(touch.fingerId, touch.position);
            }
            else if (touch.phase == TouchPhase.Moved)
            {
                this.callTouchMove(touch.fingerId, touch.position);
            }
            else if (touch.phase == TouchPhase.Ended)
            {
                this.callTouchEnd(touch.fingerId, touch.position);
                this.removeRegist(touch.fingerId);
            }
        }
    }
    private void callTouchBegan(int fingerId, Vector2 position)
    {
        if(this.dicJoyStick.ContainsKey(fingerId))
        {
            foreach(JoyStickButton jsb in this.dicJoyStick[fingerId])
            {
                jsb.onTouchBegan(position);
            }
        }
    }
    private void callTouchMove(int fingerId, Vector2 position)
    {
        if (this.dicJoyStick.ContainsKey(fingerId))
        {
            foreach (JoyStickButton jsb in this.dicJoyStick[fingerId])
            {
                jsb.onTouchMove(position);
            }
        }
    }
    private void callTouchEnd(int fingerId, Vector2 position)
    {
        if (this.dicJoyStick.ContainsKey(fingerId))
        {
            foreach (JoyStickButton jsb in this.dicJoyStick[fingerId])
            {
                jsb.onTouchEnd(position);
            }
        }
    }
    private void checkAndRegist(int fingerId, Vector2 position)
    {
        PointerEventData eventData = new PointerEventData(EventSystem.current);
        eventData.position = position;
        List<RaycastResult> results = new List<RaycastResult>();
        EventSystem.current.RaycastAll(eventData, results);

        for (int i = 0; i < results.Count; ++i)
        {
            JoyStickButton jsb = results[i].gameObject.GetComponent<JoyStickButton>();
            if (jsb && !jsb.isActive())
            {
                jsb.setActive(true);
                if (!dicJoyStick.ContainsKey(fingerId))
                {
                    dicJoyStick.Add(fingerId, new List<JoyStickButton>());
                }
                dicJoyStick[fingerId].Add(jsb);

                if (jsb.swallowTouch)
                {
                    break;
                }
            }
        }
    }
    private void removeRegist(int fingerId)
    {
        if (dicJoyStick.ContainsKey(fingerId))
        {
            foreach(JoyStickButton jsb in dicJoyStick[fingerId])
            {
                jsb.setActive(false);
            }
            dicJoyStick[fingerId].Clear();
            dicJoyStick.Remove(fingerId);
        }
    }
}

joySticButton：

using UnityEngine;

public class JoyStickButton : MonoBehaviour
{
    private bool active = false;
    public bool swallowTouch = true;
    // Start is called before the first frame update
    void Start()
    {
        
    }
    void OnDestroy()
    {

    }
    // Update is called once per frame
    void Update()
    {
        
    }
    public void onTouchBegan(Vector2 position)
    {
        Debug.Log("=========onTouchBegan=========: " + gameObject.name);
    }
    public void onTouchMove(Vector2 position)
    {
        Debug.Log("=========onTouchMove=========: " + gameObject.name);
    }
    public void onTouchEnd(Vector2 position)
    {
        Debug.Log("=========onTouchEnd=========: " + gameObject.name);
    }
    public void setActive(bool state)
    {
        this.active = state;
    }
    public bool isActive()
    {
        return active;
    }
}

才写的。。还热乎呢。。。还没来得及细细整理下，想发个文章就吃饭去了。。。
所以。。。。。。。
去吃饭了，就到这吧。。。
把joySticButton脚本的三个onTouchXXX的void前面加上virtual
用于不同的按钮或者摇杆，新建一个脚本， 然后继承joySticButton，override三个onTouch就好