虚拟遥杆实现

记录：

最近接触到了FingerGesture插件，了解其大致使用方法之后，便想用它做个简单的例子尝试一下，于是便选择了虚拟遥杆。本来是想仿着王者荣耀的操作界面做的，但是后来，就没有然后了。

该demo实现的大致功能如下：1.虚拟遥杆操作界面 2.根据操作移动场景中的物体。大致效果如下，AV画质：

具体实现：首先，遥杆操作界面的实现，其思想是用两张图片，一张做背景，一张做移动杆。这样只需捕获到手指的触屏操作，动态改变移动杆的位置便可模拟出虚拟遥杆。而捕获触摸操作既可以通过unity自带的事件系统，也可以借助一些插件，这里则是使用了FingerGesture插件，用到了其中的FingerDown Detector，FingerUpDetector，FingerMotionDetector.

FingerGesture能够识别的手势有taps, swipes, drags and pinches 等；使用时，首先要在场景中中添加FingerGestures.prefab，它是管理各种手势触屏操作的中心。其次根据需要添加相应的模块，比如识别长按，则可添加脚本Long-Press Recognizer.cs 。监听一些手指操作，则可添加FingerDown Detector，FingerUpDetector等。对于各种触摸操作事件的传递，有以下两种：（使用的Finger Gesture版本是3.1，Unity5.3.6p8）

A gesture recognizer has several ways of firing its events:

1. Using standard .NETdelegate-based events. Each gesture recognizer exposes a.NET eventthat you can subscribe to from code.
2. Using Unity'sSendMessage() method
   • The gesture event is broadcast to all the other components on the same GameObject
   • The gesture event can also be forwarded to the scene object currently being interacted with (selection). This however requires the GestureRecognizer to be equipped with a Raycaster component in order to detect scene objects.

     大意为：手势操作的监听既可通过委托注册相应事件，也可利用Unity广播传递。使用广播机制时，要注意：在没有设置Message Tagert时，消息会默认发送给挂在了该手势事件脚本的游戏体，若指定了，则只发送给指定的对象。使用委托进行事件的注册时，使用的是统一的事件接口，对于手势识别为：FingerGestures.OnGestureEvent；对于手指事件则为 FingerGestures.OnFingerEvent。在触发了事件后，在对应的处理函数中再利用GetType（）判断具体的事件类型。

     具体使用细节可查看官网文档：http://fingergestures.fatalfrog.com/docs/start。

      

     其次，则是将遥杆的操作作用到场景中的具体对象。物体移动最主要的也就是两个方面：1.移动的方向，2.移动的速度。本例对运动方向的确定由下图可直观的看出，对于速度的控制则采取的是手动设定、匀速的方式；当然也可以根据遥杆距中心点的距离不同设置不同的移动速度。

     

     主要逻辑代码：

      

     using UnityEngine;
     using System.Collections;
     using UnityEngine.EventSystems;
     public class CircleMove : MonoBehaviour{
     
         public Transform circle;
         public Transform player;
         private Vector3 origin;
     
         public float rotate_speed=1.0f;
         public float move_speed=1.0f;
         //摇杆移动半径
         public float move_area = 100.0f;
     
         public GameObject container;
     
         private bool stop=true ;
     
         public Vector2 default_pos = new Vector2(300,300);
     
         private Vector3 last_position;
         private Vector3 move_dir;
         private int first_finger_index=-1;
     	// Use this for initialization
     	void Start () {
             container.transform.position = default_pos;
             origin = circle.position;      
             
     	}
     	
     	// Update is called once per frame
     	void Update () {
        
             //EventSystem.current.IsPointerOverGameObject(Input.GetTouch(0).fingerId);//对于EventSystem.current.IsPointerOverGameObject这个函数，
             //因为EventSystem是UI的事件系统，所以IsPointerOverGameObject中的GameObject是针对UI的，而不是普遍意义上的GameObject
             if(!stop)
                 MoveGameObj(circle.position);   
     	}
     
     
         void OnFingerMove(FingerMotionEvent e)
         {
             if(first_finger_index!=e.Finger.Index)
                 return ;
             if (e.Position.x > Screen.width / 2 || e.Position.y > Screen.height / 2)
                 return;
     
             float elapsed = e.ElapsedTime;
             
             if (e.Phase == FingerMotionPhase.Started)
                 Debug.Log(e.Finger + " started moving at " + e.Position);
             else if (e.Phase == FingerMotionPhase.Updated)
             {
                            
                 if (Vector2.Distance(origin, Input.mousePosition) <= move_area)
                     circle.position = e.Position;
                 else { 
               
                     Vector2 dir=e.Position- new Vector2(origin.x, origin.y);
                     circle.position =new Vector2(origin.x, origin.y)+ dir.normalized * move_area;
                             
                 }
             }
             else if (e.Phase == FingerMotionPhase.Ended)
             {
                 Debug.Log(e.Finger + " stopped moving at " + e.Position);
                 last_position = circle.position;
             }
         }
         void OnFingerStationary(FingerMotionEvent e)
         {
             //float elapsed = e.ElapsedTime;
     
             //if (e.Phase == FingerMotionPhase.Started)
             //    Debug.Log(e.Finger + " started stationary state at " + e.Position);
             //else if (e.Phase == FingerMotionPhase.Updated)
             //    Debug.Log(e.Finger + " is still stationary at " + e.Position);
             //else if (e.Phase == FingerMotionPhase.Ended)
             //{
             //    Debug.Log(e.Finger + " stopped being stationary at " + e.Position);
             //    circle.position = origin;
             //}
         }
     
         void OnFingerDown(FingerDownEvent e)
         {
             if(first_finger_index!=-1)
                 return ;
             first_finger_index = e.Finger.Index;
             Debug.Log(" first_finger_index >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>" + first_finger_index);
             if (e.Position.x < Screen.width / 2 && e.Position.y < Screen.height / 2)//判断出触摸处是否可显示虚拟遥杆，可则显示，不可则退出
             {
                
                 container.transform.position = e.Position;
                 origin = circle.position;
                 stop = false;
             }
             else {
     
                 return;
             
             }
             Debug.Log(e.Finger + " Down at " + e.Position + " on object:" + e.Selection.name);
         }
         void OnFingerUp(FingerUpEvent e)
         {
             Debug.LogError("tappppppp2555552=====111111111");
             if (first_finger_index != e.Finger.Index)
                 return;
             container.transform.position = default_pos;
             circle.localPosition=Vector2.zero;
             origin = circle.position;
             stop = true;
             first_finger_index=-1;
         }
     
     
         void MoveGameObj(Vector2 target) {
           
             if (Vector2.Distance(target, last_position) > 0.5) {               
                 Vector2 dir = target - new Vector2(origin.x, origin.y);      
                 move_dir = new Vector3(dir.x, 0, dir.y);
             }           
                  
             player.position += move_dir.normalized * move_speed * Time.deltaTime;
             player.rotation = Quaternion.Lerp(player.rotation, Quaternion.LookRotation(move_dir), rotate_speed * Time.deltaTime);
           
         }
         void OnTap(TapGesture gesture)
         {
             // Number of taps performed
             Debug.LogError("tappppppp=====");
         }
     
     }