Unity 画线

一、使用Vectrosity插件

1. 画一条（X0,Y0）到（X1,Y1）的线

using Vectrosity 
public class DrawLine:MonoBehaviour
{
    public VectorLine energyLine；
    List linePoints；
    float lineWeight = 2f；
    public void LineDraw_1()
        {
            linePoints = new List();
            linePoints.Add(new Vector2(X0, Y0));
            linePoints.Add(new Vector2(X1, Y1));
            energyLine = new VectorLine("Energy", linePoints, lineWeight, LineType.Continuous);
            energyLine.Draw();
        }
}

如果有画折线的话，将每个折点加入List中。

2. 正弦曲线

using Vectrosity 
public class DrawLine:MonoBehaviour
{
    public VectorLine energyLine；
    List linePoints；
    float lineWeight = 2f；
    public void LineDraw_2()
    {
          linePoints = new List();
          energyLine = new VectorLine("Energy", linePoints, lineWeight, LineType.Continuous);
          for (int i = 0; i < 200; i++)
          {
          //y=Asin(ωx+φ)+k   A——振幅 (ωx+φ)——相位 φ——初相 k——偏距 ω——角速度， 控制正弦周期
              energyLine.points2.Add(new Vector2(i , A * Mathf.Sin( ( (a * i) + b) + K) );
          }   
          energyLine.Draw();
    }
}     

删除线：

   public void Des()
    {
        List list = new List();
        GameObject a = GameObject.Find("VectorCanvas");
        if (a)
        {
            foreach (Transform child in a.transform)
            {
                if (child.name.Equals("Energy"))
                {
                    list.Add(child);
                }               
            }
            for (int i = 0; i < list.Count; i++)
            {
                Destroy(list[i].gameObject);
            }
        }
    }

二、使用LineRenderer

新建物体Tr0，挂载脚本drawLine，添加LineRenderer组件。Tr0移动时会画出Tr0移动的轨迹。
PS：开始绘制的时候将脚本打开，绘制完之后关闭。不然会一直绘制，卡！

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class drawLine : MonoBehaviour
{
    private LineRenderer line;
    Vector3[] path;
    private float time = 0;
    List pos = new List();
    void Awake()
    {
        path = pos.ToArray();//初始化
        line = GetComponent();//获得该物体上的LineRender组件
    }
    void Update()
    {
        time += Time.deltaTime;
        if (time > 0.1)//每0.1秒绘制一次
        {
            time = 0;
            pos.Add(transform.position);//添加当前坐标进链表
            path = pos.ToArray();//转成数组
        }
        if (path.Length != 0)//有数据时候再绘制
        {
            line.positionCount = path.Length;//设置顶点数      
            line.SetPositions(path);//设置顶点位置
        }
    }
}