Unity GL画折线

新建一个脚本，这个物体得挂在有摄像机组件的物体上才能生效

OnPostRender() 这个函数才会被自动调用（类似生命周期自动调用）

然后就可以代码画线了，原理是openGL的画线

1using UnityEngine;
2using System.Collections;
3using System.Collections.Generic;
4
5/// <summary>
6/// GL画图
7/// </summary>
8public class GLDraw : UnityNormalSingleton<GLDraw> {
9
10    public Transform p1;
11    public Transform p2;
12    private List<Vector2> pointList;
13    private bool isOpen;
14
15    private Material mat;
16    private Shader shader;
17
18    private void Start()
19    {
20        pointList = new List<Vector2>();
21        shader = Shader.Find("Unlit/Color");
22        mat = new Material(shader);
23        mat.SetColor("Main Color", Color.black);
24    }
25
26    public void DrawLine(List<object> list)
27    {
28        pointList.Clear();
29        for (int i = 0; i < list.Count; i++)
30        {
31            Vector2 screenPos = (Vector2)list[i];
32            pointList.Add(new Vector2(screenPos.x, Screen.height - screenPos.y));
33        }
34    }
35
36    public void ShowLine(bool b)
37    {
38        isOpen = b;
39    }
40
41    void OnPostRender()
42    {
43        if (!isOpen)
44        {
45            return;
46        }
47
48        //mat = new Material(Shader.Find("Unlit/Color"));
49        //Debug.Log("调用");
50        //if (!mat)
51        //{
52        //    Debug.LogError("Please Assign a material on the inspector");
53        //    return;
54        //}
55        GL.PushMatrix(); //保存当前Matirx
56        mat.SetPass(0); //刷新当前材质
57        GL.LoadPixelMatrix();//设置pixelMatrix
58        GL.Color(Color.yellow);
59        GL.Begin(GL.LINES);
60
61        //画2次，奇偶数画连续折线法
62        for (int i = 0; i < pointList.Count; i++)
63        {
64            GL.Vertex3(pointList[i].x, pointList[i].y, 0);
65        }
66        for (int i = 1; i < pointList.Count; i++)
67        {
68            GL.Vertex3(pointList[i].x, pointList[i].y, 0);
69        }
70　　　　  //单次画线发
71        //GL.Vertex3(0, 0, 0);//GL.Vertex3(Screen.width, Screen.height, 0);
72　　　　  //固定2点画
73        //GL.Vertex3(p1.position.x, p1.position.y, 0);
74        //GL.Vertex3(p2.position.x, p2.position.y, 0);
75        GL.End();
76        GL.PopMatrix();//读取之前的Matrix
77    }
78}