【原】unity3D调用GL任意画线
白色上面为什么画不上？
此文是对某位大神文章的翻译，忘记从哪摘抄的了 原文使用js写的我把它改成C#。此文存在一个问题，当屏幕上有texture的话，貌似texture上画不上。期待高手一块解决。另外当快速拖动鼠标时，发现画的曲线不够平滑，正在尝试用贝塞尔解决，期待高手一块探讨。GLDraw
快速画线，不光滑问题搞定。
贝塞尔曲线：
1 using UnityEngine; 2 using System.Collections; 3 4 5 public class joint{ 6 public Vector3 org; 7 public Vector3 end; 8 } 9 10 public class TestGL : MonoBehaviour { 11 12 Event e ; 13 private Vector3 orgPos; 14 private Vector3 endPos; 15 bool canDrawLines; 16 ArrayList posAL; 17 public Material lineMaterial; 18 // Use this for initialization 19 void Start () 20 { 21 posAL=new ArrayList(); 22 } 23 24 void Update() 25 { 26 if(Input.GetMouseButton(0)) 27 { 28 canDrawLines = true; 29 } 30 31 32 if(e.type!=null &canDrawLines) 33 { 34 if(e.type == EventType.MouseDown) 35 { 36 orgPos=Input.mousePosition; 37 endPos=Input.mousePosition; 38 39 } 40 if(e.type==EventType.MouseDrag) 41 { 42 endPos=Input.mousePosition; 43 joint tempjoint = new joint(); 44 tempjoint.org=orgPos; 45 tempjoint.end=endPos; 46 posAL.Add(tempjoint); 47 orgPos=Input.mousePosition; 48 } 49 if(e.type==EventType.MouseUp) 50 { 51 52 endPos=Input.mousePosition; 53 } 54 } 55 56 } 57 58 /// <summary> 59 /// GLs the draw line1. 60 /// 61 /// * 62 /// * * 63 /// * * 64 /// * * * //红点为begin 灰点为end1 黑点为中点 65 /// * * 66 /// * * 67 /// * * 68 ///
69 /// </summary> 70 void GLDrawLine1( ) 71 { 72 //DrawBezier(new Vector2(100,100),new Vector2(300,500),new Vector2(800,100),new Vector2(600,700),Color.red,1); 73 for(int i=0;i<posAL.Count-1;i+=2) 74 { 75 joint temp=(joint)posAL[i];//左边*线的对象 包含起点、终点 76 joint temp1=(joint)posAL[i+1];//右边*线的对象 包含起点、终点 77 Vector3 begin=(temp.org+temp.end)/2f;//左边*线的中点坐标 78 Vector3 end1=(temp1.org+temp1.end)/2f;//右边*线的中点坐标 79 Vector3 x1=(begin+end1)/2f;//计算中点坐标 80 Vector3 offSet=temp.end-x1;//顶点和中点的差值 81 Vector3 startTangent=new Vector3(begin.x+offSet.x,begin.y+offSet.y,0);//左边控制点 82 Vector3 endTangent=new Vector3(end1.x+offSet.x,end1.y+offSet.y,0);//右边的控制点 83 DrawBezier(temp.org,startTangent,temp1.end,endTangent,Color.red,1); 84 } 85 } 90 void DrawLine(Vector2 beg ,Vector2 end ) 91 { 92 if(!canDrawLines) 93 return; 94 GL.PushMatrix (); 95 GL.LoadOrtho (); 96 beg.x=beg.x/Screen.width; // 97 end.x=end.x/Screen.width; 98 beg.y=beg.y/Screen.height; 99 end.y=end.y/Screen.height; 100 lineMaterial.SetPass( 0 ); 101 GL.Begin( GL.LINES ); 102 GL.Color( new Color(1,1,1,0.5f) ); 103 GL.Vertex3( beg.x,beg.y,0); 104 GL.Vertex3( end.x,end.y,0); 105 GL.End(); 106 GL.PopMatrix (); 107 } 108 109 void OnGUI() 110 { 111 e = Event.current; 112 113 if(GUI.Button(new Rect(150,0,100,50),"End Lines")) 114 { 115 ClearLines(); 116 } 117 } 118 void ClearLines() 119 { 120 canDrawLines = false; 121 posAL.Clear(); 122 } 126 void OnPostRender() 127 { 128 GLDrawLine1() ; 129 } 130 131 public void DrawBezier(Vector2 start, Vector2 startTangent, Vector2 end, Vector2 endTangent, Color color, float width) 132 { 133 int segments = Mathf.FloorToInt((start - end).magnitude/20) *3; // Three segments per distance of 20 134 DrawBezier(start, startTangent, end, endTangent, color, width, segments); 135 } 136 137 public void DrawBezier(Vector2 start, Vector2 startTangent, Vector2 end, Vector2 endTangent, Color color, float width, int segments) 138 { 139 Vector2 startVector = CubeBezier(start, startTangent, end, endTangent, 0); 140 for (int i = 1; i < segments; i++) 141 { 142 Vector2 endVector = CubeBezier(start, startTangent, end, endTangent, i/(float)segments); 143 DrawLine(startVector, endVector); 144 startVector = endVector; 145 } 146 } 147 private Vector2 CubeBezier(Vector2 s, Vector2 st, Vector2 e, Vector2 et, float t) 148 { 149 float rt = 1-t; 150 float rtt = rt * t; 151 return rt*rt*rt * s + 3 * rt * rtt * st + 3 * rtt * t * et + t*t*t* e; 152 } 153 }
