一.首先点击UI创建两个Image，将Image的Source Image改成自己想要的Texture即可，然后在Canvas下创建一空物体，将两个Image放在空物体下作为他的子对象；
然后为可以拖动的Image编写脚本，脚本如下：（有注释，就不多说了）
using UnityEngine;
using System.Collections;
using UnityEngine.UI;
using UnityEngine.EventSystems;
public class JoyStick : MonoBehaviour, IPointerDownHandler, IPointerUpHandler, IDragHandler//需要注意继承的接口，接口内的方法需要实现
{
///
/// 摇杆大半径
/// 以像素为单位
///
public float JoyStickRadius = 50;
///
/// 摇杆重置所诉
///
public float JoyStickResetSpeed = 5.0f;
///
/// 当前物体的Transform组件
///
private RectTransform selfTransform;
///
/// 是否触摸了虚拟摇杆
///
private bool isTouched = false;
///
/// 虚拟摇杆的默认位置
///
private Vector2 originPosition;
///
/// 虚拟摇杆的移动方向
///
private Vector2 touchedAxis;
public Vector2 TouchedAxis
{
get
{
if (touchedAxis.magnitude < JoyStickRadius)
return touchedAxis.normalized / JoyStickRadius;
return touchedAxis.normalized;
}
}
///
/// 定义触摸开始事件委托
///
public delegate void JoyStickTouchBegin(Vector2 vec);
///
/// 定义触摸过程事件委托
///
/// 虚拟摇杆的移动方向
public delegate void JoyStickTouchMove(Vector2 vec);
///
/// 定义触摸结束事件委托
///
public delegate void JoyStickTouchEnd();
///
/// 注册触摸开始事件
///
public event JoyStickTouchBegin OnJoyStickTouchBegin;
///
/// 注册触摸过程事件
///
public event JoyStickTouchMove OnJoyStickTouchMove;
///
/// 注册触摸结束事件
///
public event JoyStickTouchEnd OnJoyStickTouchEnd;
void Start()
{
//初始化虚拟摇杆的默认方向
selfTransform = this.GetComponent();
originPosition = selfTransform.anchoredPosition;
}
public void OnPointerDown(PointerEventData eventData)
{
isTouched = true;
touchedAxis = GetJoyStickAxis(eventData);
if (this.OnJoyStickTouchBegin != null)
this.OnJoyStickTouchBegin(TouchedAxis);
}
public void OnPointerUp(PointerEventData eventData)
{
isTouched = false;
selfTransform.anchoredPosition = originPosition;
touchedAxis = Vector2.zero;
if (this.OnJoyStickTouchEnd != null)
this.OnJoyStickTouchEnd();
}
public void OnDrag(PointerEventData eventData)
{
touchedAxis = GetJoyStickAxis(eventData);
if (this.OnJoyStickTouchMove != null)
this.OnJoyStickTouchMove(TouchedAxis);
}
void Update()
{
//当虚拟摇杆移动到大半径时摇杆无法拖动
//为了确保被控制物体可以继续移动
//在这里手动触发OnJoyStickTouchMove事件
if (isTouched && touchedAxis.magnitude >= JoyStickRadius)
{
if (this.OnJoyStickTouchMove != null)
this.OnJoyStickTouchMove(TouchedAxis);
}
//松开虚拟摇杆后让虚拟摇杆回到默认位置
if (selfTransform.anchoredPosition.magnitude > originPosition.magnitude)
selfTransform.anchoredPosition -= TouchedAxis * Time.deltaTime * JoyStickResetSpeed;
}
///
/// 返回虚拟摇杆的偏移量
///
/// The joy stick axis.
/// Event data.
private Vector2 GetJoyStickAxis(PointerEventData eventData)
{
//获取手指位置的世界坐标
Vector3 worldPosition;
if (RectTransformUtility.ScreenPointToWorldPointInRectangle(selfTransform,
eventData.position, eventData.pressEventCamera, out worldPosition))
selfTransform.position = worldPosition;
//获取摇杆的偏移量
Vector2 touchAxis = selfTransform.anchoredPosition - originPosition;
//摇杆偏移量限制
if (touchAxis.magnitude >= JoyStickRadius)
{
touchAxis = touchAxis.normalized * JoyStickRadius;
selfTransform.anchoredPosition = touchAxis;
}
return touchAxis;
}
} 二.接下来，就是拖拽p_w_picpath使物体能够移动了；
为该物体添加脚本：
using UnityEngine;
using System.Collections;
public class JoyStick3D : MonoBehaviour
{
private JoyStick js;
void Start()
{
js = GameObject.FindObjectOfType();
js.OnJoyStickTouchBegin += OnJoyStickBegin;
js.OnJoyStickTouchMove += OnJoyStickMove;
js.OnJoyStickTouchEnd += OnJoyStickEnd;
}
void OnJoyStickBegin(Vector2 vec)
{
Debug.Log("开始触摸虚拟摇杆");
}
void OnJoyStickMove(Vector2 vec)
{
Debug.Log("正在移动虚拟摇杆");
//设置角色朝向
Quaternion q = Quaternion.LookRotation(new Vector3(vec.x, 0, vec.y));
transform.rotation = q;
//移动角色
transform.Translate(Vector3.forward * 75f * Time.deltaTime);
}
void OnJoyStickEnd()
{
Debug.Log("触摸移动摇杆结束");
}
void OnGUI()
{
GUI.Label(new Rect(30, 30, 200, 30), "3D模式下的虚拟摇杆测试");
}
} 三.接着可以试着运行，可以看到物体可以随着p_w_picpath的拖动而移动，但是有不好的地方，就是拖拽的p_w_picpath超过半径所设置的半径JoyStickRadius时，p_w_picpath的位置就会固定在一个位置不动，
而且当在半径范围内时，物体不会持续移动，这个就不好了，不知道有那位大神能够邦杰呢？
创新互联www.cdcxhl.cn，专业提供香港、美国云服务器，动态BGP最优骨干路由自动选择，持续稳定高效的网络助力业务部署。公司持有工信部办法的idc、isp许可证， 机房独有T级流量清洗系统配攻击溯源，准确进行流量调度，确保服务器高可用性。佳节活动现已开启，新人活动云服务器买多久送多久。
