LineRenderer实现一个画线组件

 1 using System;
 2 using UnityEngine;
 3 
 4 class UILine
 5 {
 6     GameObject targetObj;
 7     LineRenderer lineRenderer;      //LineRenderer渲染出的线段的两个端点是3D世界中的点
 8     int index = 0;
 9     int poinCount = 0;  //线段的端点数
10     Vector3 position;
11 
12     public void Start(GameObject go, Color beginColor, Color endColor, float begineWidth, float endWidth)
13     {
14         targetObj = go;
15         if (null != targetObj)
16         {
17             targetObj.SetActive(true);
18             lineRenderer = targetObj.GetComponent<LineRenderer>();
19 
20             if (null == lineRenderer)
21                 lineRenderer = targetObj.AddComponent<LineRenderer>();
22         }
23 
24         if (null != lineRenderer)
25         {
26             //颜色
27             lineRenderer.startColor = beginColor;
28             lineRenderer.endColor = endColor;
29 
30             //宽度
31             lineRenderer.startWidth = begineWidth;
32             lineRenderer.endWidth = endWidth;
33         }
34 
35         index = poinCount = 0;
36     }
37 
38     public void Update()
39     {
40         if (Input.GetMouseButton(0))
41         {
42             //屏幕坐标转换为世界坐标
43             position = Camera.main.ScreenToWorldPoint(new Vector3(Input.mousePosition.x, Input.mousePosition.y, 1.0f));
44             //端点数+1
45             poinCount++;
46             //设置线段的端点数
47             lineRenderer.positionCount = poinCount;
48 
49             //连续绘制线段
50             while (index < poinCount)
51             {
52                 //两点确定一条直线，所以我们依次绘制点就可以形成线段了
53                 lineRenderer.SetPosition(index, position);
54                 index++;
55             }
56         }
57     }
58 
59     public static UILine BeginLine(GameObject go, Color beginColor, Color endColor, float beginWidth, float endWidth)
60     {
61         UILine line = new UILine();
62         line.Start(go, beginColor, endColor, beginWidth, endWidth);
63         return line;
64     }
65 }