using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
/// <summary>
/// 手势操作
/// </summary>
public class TouchScreen : MonoBehaviour
{
    public Transform currentTra;

    private Touch oldTouch1;  //上次触摸点1(手指1)  
    private Touch oldTouch2;  //上次触摸点2(手指2)  

    Touch newTouch1;
    Touch newTouch2;

    float divisor = 9.353074f;//初始模型缩放比例
    public float MaxScale;
    public float MinScale;
    public bool IsTouch;
    // Start is called before the first frame update
    private void Awake()
    {
        MaxScale = 2 * divisor;
        MinScale = 0.8f * divisor;
    }
    void Start()
    {
        //currentTra = this.transform;
    }

    // Update is called once per frame 
    void Update()
    {
        if (IsTouch)
        {
            //没有触摸  
            if (Input.touchCount <= 0)
            {
                return;
            }
            //单点拖动
            else if (Input.touchCount == 1 && Input.GetTouch(0).phase == TouchPhase.Moved)
            {
                //
                //var deltaposition = Input.GetTouch(0).deltaPosition;


                //transform.Translate(new Vector3(deltaposition.x * 0.01f, deltaposition.y * 0.01f, 0f), Space.World);
                //Debug.Log("单点触摸， 水平上下旋转  ");
                Touch touch = Input.GetTouch(0);
                Vector2 deltaPos = touch.deltaPosition;//位置增量

                if (Mathf.Abs(deltaPos.x) >= 3 || Mathf.Abs(deltaPos.y) >= 3)
                {

                    transform.Rotate(Vector3.down * deltaPos.x, Space.World);//绕y轴旋转
                    transform.Rotate(Vector3.right * deltaPos.y, Space.World);//绕x轴
                }

            }
            //双指旋转  && 缩放
            else if (2 <= Input.touchCount)
            {
                ////Debug.Log("单点触摸， 水平上下旋转  ");
                //Touch touch = Input.GetTouch(0);
                //Vector2 deltaPos = touch.deltaPosition;//位置增量

                //if (Mathf.Abs(deltaPos.x) >= 3 || Mathf.Abs(deltaPos.y) >= 3)
                //{

                //    transform.Rotate(Vector3.down * deltaPos.x, Space.World);//绕y轴旋转
                //    transform.Rotate(Vector3.right * deltaPos.y, Space.World);//绕x轴
                //}

                //缩放
                newTouch1 = Input.GetTouch(0);//
                newTouch2 = Input.GetTouch(1);
                if (newTouch2.phase == TouchPhase.Began)
                {
                    oldTouch2 = newTouch2;
                    oldTouch1 = newTouch1;
                    return;
                }
                float oldDistance = Vector2.Distance(oldTouch1.position, oldTouch2.position);//计算两点距离
                float newDistance = Vector2.Distance(newTouch1.position, newTouch2.position);//计算两点距离
                float offset = newDistance - oldDistance;


                if (Mathf.Abs(offset) >= 3)
                {
                    Debug.Log(offset);
                    //放大因子， 一个像素按 0.01倍来算(100可调整)  
                    float scaleFactor = offset / 100f;
                    Vector3 localScale = transform.localScale;
                    Vector3 scale = new Vector3(localScale.x + scaleFactor,
                                                localScale.y + scaleFactor,
                                                localScale.z + scaleFactor);

                    //最小缩放到 0.3 倍 最大1.5倍 
                    if (scale.x > MinScale && scale.x < MaxScale)
                    {
                        transform.localScale = scale;//赋新值
                    }

                    //记住最新的触摸点，下次使用  
                    oldTouch1 = newTouch1;
                    oldTouch2 = newTouch2;
                }

            }
        }
        
    }
}