鼠标点击拖拽方式截图

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using System.IO;
/// <summary>
/// 鼠标左键点击拖动方式截图
/// </summary>
public class CapstureScreen : MonoBehaviour {

    string filePath;
void Start () {
    filePath = Application.streamingAssetsPath + "/1.png";
}

Rect rect;
Vector3 s_pos;
Vector3 e_pos;
bool isDraw;
void Update()
{
    if(Input.GetMouseButtonDown(0))
    {
        s_pos = Input.mousePosition;
    }
    if(Input.GetMouseButton(0))
    {
        e_pos = Input.mousePosition;
        isDraw = true;
    }

    if(Input.GetMouseButtonUp(0))
    {
        isDraw = false;
        e_pos = Input.mousePosition;

        rect = new Rect(Mathf.Min(s_pos.x, e_pos.x),
                        Mathf.Min(s_pos.y, e_pos.y),
                        Mathf.Abs(s_pos.x - e_pos.x),
                        Mathf.Abs(s_pos.y - e_pos.y));
        StartCoroutine(Capsture(filePath, rect));
    }
}


IEnumerator Capsture(string filePath, Rect rect)
{
    yield return new WaitForEndOfFrame();
    Texture2D tex = new Texture2D((int)rect.width, (int)rect.height);

    tex.ReadPixels(rect, 0, 0) ;
    tex.Apply();

    byte[] result =    tex.EncodeToPNG();
    //文件夹
    if(!Directory.Exists(Application.streamingAssetsPath))
        Directory.CreateDirectory(Application.streamingAssetsPath);
    File.WriteAllBytes(filePath, result);
    print ("Finish");
}

//1.GL的回调函数
//2.Material
public Material lineMaterial;

void OnPostRender() {
    if(!isDraw) return;
    print (s_pos);
    Vector3 sPos = Camera.main.ScreenToWorldPoint(s_pos + new Vector3(0, 0, 10));
    Vector3 ePos = Camera.main.ScreenToWorldPoint(e_pos + new Vector3(0, 0, 10));

    print(string.Format("GL.....{0},  {1}", sPos, ePos));
    // Set your materials Done
    GL.PushMatrix();
    // yourMaterial.SetPass( );
    lineMaterial.SetPass(0);    //告诉GL使用该材质绘制
    // Draw your stuff
    //始终在最前面绘制
    GL.invertCulling = true;
    GL.Begin(GL.LINES);        //开始绘制

    GL.Vertex(sPos);
    GL.Vertex(ePos);
    //如果想要绘制，矩形，将下面代码启动
// GL.Vertex(sPos);
// GL.Vertex(new Vector3(ePos.x, sPos.y, 0));
//
// GL.Vertex(new Vector3(ePos.x, sPos.y, 0));
// GL.Vertex(ePos);
//
// GL.Vertex(ePos);
// GL.Vertex(new Vector3(sPos.x, ePos.y, 0));
//
// GL.Vertex(new Vector3(sPos.x, ePos.y, 0));
// GL.Vertex(sPos);
GL.End(); //结束绘制

    GL.PopMatrix();
}

IEnumerator Capsture(string filePath)
{
    yield return new WaitForEndOfFrame();
    Texture2D tex = new Texture2D(Screen.width, Screen.height);
    tex.ReadPixels(new Rect(0, 0, Screen.width, Screen.height), 0, 0);
    tex.Apply();
    byte[] result =    tex.EncodeToPNG();
    //文件夹
    if(!Directory.Exists(Application.streamingAssetsPath))
        Directory.CreateDirectory(Application.streamingAssetsPath);

    File.WriteAllBytes(filePath, result);
    print ("Finish");
}
}