UGUI_My02_ 摇杆_实现原理与实现策略--(最最最简单的控制摇杆实现方法)

• 知识从上一篇接入

[策略思路]:

    1.声明一个isPress Bool 类型记录“手柄”的长按状态，在手柄”按下时isPress设为true，并InvokeRepeating,一个你需要实现的功能方法，手柄”抬起时isPress设为false,并利用isPress状态进行（实现的功能方法）的排错。

    2.利用手柄按下与抬起的矢量向量进行位移，并在抬起时复位

    3.将摇杆的手柄的背景组件“BackGround”的（宽度/2) 得到手柄的运动半径进行条件限制

[实现代码]:

using UnityEngine;
using UnityEngine.EventSystems;

public class ControlHandle : MonoBehaviour,IPointerUpHandler,IPointerDownHandler{

    public GameObject BackGround;

    private bool isPress = false;
    private Vector3 mStartPostion;
    private Vector3 mEndPostion;

    private float mWidth;

    private void Start()
    {
        mWidth = BackGround.GetComponent().rect.width / 2;
    }
    public void OnPointerDown(PointerEventData eventData)
    {
        isPress = true;
        mStartPostion = Input.mousePosition;
        InvokeRepeating("MyFunction", 0, 0.01f);
    }

    public void OnPointerUp(PointerEventData eventData)
    {
        isPress = false;
        CancelInvoke("MyFunction");
        InvokeRepeating("MyFunction2", 0, 0.01f);
    }
    private void MyFunction()
    {
        if (isPress)
        {
            mEndPostion = Input.mousePosition;
            Vector3 dirt = mEndPostion - mStartPostion;
            Vector3 targetDirt = dirt.normalized * mWidth;

            if (dirt.magnitude <= mWidth)
                targetDirt = dirt;
            transform.localPosition = Vector3.Lerp(transform.localPosition, targetDirt, 0.5f);
        }
    }
    private void MyFunction2() {
        transform.localPosition = Vector3.Lerp(transform.localPosition, Vector3.zero, 0.1f);
        if (transform.localPosition.magnitude < 0.1f)
            CancelInvoke("MyFunction2");
    }
}

[实现代码]:

(最简洁版)DOTween版：

using UnityEngine;
using UnityEngine.EventSystems;
using DG.Tweening;

public class ControlHandle : MonoBehaviour,IPointerUpHandler,IPointerDownHandler{

    public GameObject BackGround;

    private bool isPress = false;
    private Vector3 mStartPostion;
    private Vector3 mEndPostion;

    private float mWidth;

    private void Start()
    {
        mWidth = BackGround.GetComponent().rect.width / 2;
    }
    public void OnPointerDown(PointerEventData eventData)
    {
        isPress = true;
        mStartPostion = Input.mousePosition;
        InvokeRepeating("MyFunction", 0, 0.01f);
    }

    public void OnPointerUp(PointerEventData eventData)
    {
        isPress = false;
        CancelInvoke("MyFunction");
        transform.DOLocalMove(new Vector3(0, 0, 0), 0.1f);
    }
    public void MyFunction()
    {
        if (isPress) {
            mEndPostion = Input.mousePosition;
            Vector3 dirt = mEndPostion - mStartPostion;
            Vector3 targetDirt = dirt.normalized * mWidth;

            if (dirt.magnitude <= mWidth)
                targetDirt = dirt;
            transform.DOLocalMove(targetDirt, 0.1f);

        }
    }

}