UnityGL4.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;


public class UnityGL4 : MonoBehaviour {

	static Material lineMaterial;

	static int objectCount=100;
	float[] val1= new float[objectCount];
	float[] val2= new float[objectCount];

	public float lineWidth = 100.0f;
	void Start () {
  	//OnRendererObject()の中は繰り返し呼ばれるため(Update()のように)、星の図形をランダム配置させるための変数をここで宣言する
		for(int i=0;i<objectCount;i++){
			val1[i]= Random.Range(-100,objectCount);
			val2[i] = Random.Range(-200,objectCount);
		}
	}

	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");
			//Shader shader = Shader.Find ("Custom/Texture");
			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);
		}
	}

	public void OnRenderObject (){
		CreateLineMaterial ();
		// Apply the line material
		lineMaterial.SetPass (0);
		GL.PushMatrix ();
		// Set transformation matrix for drawing to
		// match our transform
		GL.MultMatrix (transform.localToWorldMatrix);
	
  // Draw lines
		GL.Begin (GL.LINES);
	  	GL.Color (new Color (0, 1, 0.25f, 0.8F));
		//星を描く
		for(int m=0;m<objectCount;m++){
			GL.Vertex3 (-0.71f+val1[m],1.49f+val2[m],5.0f);
			GL.Vertex3 (-1.72f+val1[m],-1.68f+val2[m],5.0f);

			GL.Vertex3 (-1.72f+val1[m],-1.68f+val2[m],5.0f);
			GL.Vertex3 (0.82f+val1[m],0.15f+val2[m],5.0f);

			GL.Vertex3 (0.82f+val1[m],0.15f+val2[m],5.0f);
			GL.Vertex3 (-2.3f+val1[m],0.15f+val2[m],5.0f);

			GL.Vertex3 (-2.3f+val1[m],0.15f+val2[m],5.0f);
			GL.Vertex3 (0.3f+val1[m],-1.68f+val2[m],5.0f);

			GL.Vertex3 (0.3f+val1[m],-1.68f+val2[m],5.0f);//ここで止めることで、次の星の間を線で結ぶ書き方にする
		}
		GL.End ();
		GL.PopMatrix ();

	}

}