1、打开Unity，新建一个空工程，具体如下图
2、在工程中，添加一个脚本，然后右键或者双击编辑脚本，具体如下图
3、脚本内容如下：1、首先new一个添加点用来绘制；2、一稍僚敉视个创建材质的函数，创建绘制需要的材质；3、在 OnRenderObject() 函数绘制线段和平面；4、分别创建画线和绘制平面的挣窝酵聒函数接口，具体如下图
4、脚本具体内容：using System.Collect坡纠课柩ions.Generic;using UnityEngine;public class GLPaint : MonoBehaviour { List<Vector3> tmplist; // 存放点的列表 void Start() { // 初始化存点的列表，并添加一些点 tmplist = new List<Vector3>(); tmplist.Add(new Vector3(0,0,0)); tmplist.Add(new Vector3(0,3,0)); tmplist.Add(new Vector3(3,3,0)); tmplist.Add(new Vector3(3,0,0)); } /// <summary> /// 创建材质，方便 GL 绘图使用 /// </summary> static Material lineMaterial; static void CreateLineMaterial() { if (!lineMaterial) { // Unity has a built-in shader that is useful for drawing // simple colored things. Shader shader = Shader.Find("Hidden/Internal-Colored"); lineMaterial = new Material(shader); lineMaterial.hideFlags = HideFlags.HideAndDontSave; // Turn on alpha blending lineMaterial.SetInt("_SrcBlend", (int)UnityEngine.Rendering.BlendMode.SrcAlpha); lineMaterial.SetInt("_DstBlend", (int)UnityEngine.Rendering.BlendMode.OneMinusSrcAlpha); // Turn backface culling off lineMaterial.SetInt("_Cull", (int)UnityEngine.Rendering.CullMode.Off); // Turn off depth writes lineMaterial.SetInt("_ZWrite", 0); } } /// <summary> /// MonoBehaviour 频调函数 /// </summary> public void OnRenderObject() { CreateLineMaterial(); // Apply the line material lineMaterial.SetPass(0); //DrawLines(); // GL 画线函数 //DrawLines(tmplist); DrawTriangle(tmplist); } /// <summary> /// GL画线函数 /// </summary> /// <param name="tmpBorderPoints">点的列表</param> void DrawLines(List<Vector3> tmpBorderPoints) { GL.PushMatrix(); // Draw lines GL.Begin(GL.LINES); // Vertex colors change from red to green GL.Color(Color.red); if (tmpBorderPoints != null) { for (int i = 0; i < tmpBorderPoints.Count; i++) { Vector3 posOne = tmpBorderPoints[i]; Vector3 posTwo = tmpBorderPoints[(i + 1) % tmpBorderPoints.Count]; // One vertex at transform position GL.Vertex3(posOne.x, posOne.y, posOne.z); // Another vertex at edge of circle GL.Vertex3(posTwo.x, posTwo.y, posTwo.z); } } GL.End(); GL.PopMatrix(); } /// <summary> /// GL 平面绘制 /// </summary> /// <param name="tmpBorderPoints"></param> void DrawTriangle(List<Vector3> tmpBorderPoints) { GL.PushMatrix(); // Set transformation matrix for drawing to // match our transform GL.MultMatrix(transform.localToWorldMatrix); // Draw lines GL.Begin(GL.TRIANGLES); // Vertex colors change from red to green GL.Color(Color.green); if (tmpBorderPoints != null) { for (int i = 0; i < tmpBorderPoints.Count; i++) { if (i < tmpBorderPoints.Count - 2) { // 以第一个为原点，绘制三角形面 Vector3 posZero = tmpBorderPoints[0]; Vector3 posOne = tmpBorderPoints[i + 1]; Vector3 posTwo = tmpBorderPoints[(i + 2)]; GL.Vertex3(posZero.x, posZero.y, posZero.z); GL.Vertex3(posOne.x, posOne.y, posOne.z); GL.Vertex3(posTwo.x, posTwo.y, posTwo.z); } } } GL.End(); GL.PopMatrix(); } }
5、脚本编译正确，回到Unity，运行场景，这次绘制的线段，具体如下图
6、简单修改脚本，运行场景，这次绘制平面，具体如下图
