先建立一个RawImage,然后再在这个图片上加个LineRenderer组件,再建个材质球,把材质球的Shader改成Particles/Additive,把材质球拖给LineRenderer组件的Materials/Element 0(不拖也可以),最后再把代码拖给空物体即可,代码的Target是RawImage,下面的代码
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class huaxian : MonoBehaviour
{
private GameObject clone;
private LineRenderer line;
int i;
//带有LineRender物体
public GameObject target;
void Start()
{
Debug.Log("请开始写字");
}
// Update is called once per frame
void Update()
{
if (Input.GetMouseButtonDown(0))
{
//实例化对象
clone = (GameObject)Instantiate(target, target.transform.position, Quaternion.identity);
//获得该物体上的LineRender组件
line = clone.GetComponent<LineRenderer>();
//设置起始和结束的颜色
line.SetColors(Color.red, Color.blue);
//设置起始和结束的宽度
line.SetWidth(0.2f, 0.1f);
//计数
i = 0;
}
if (Input.GetMouseButton(0))
{
//每一帧检测,按下鼠标的时间越长,计数越多
i++;
//设置顶点数
line.SetVertexCount(i);
//设置顶点位置(顶点的索引,将鼠标点击的屏幕坐标转换为世界坐标)
line.SetPosition(i - 1, Camera.main.ScreenToWorldPoint(new Vector3(Input.mousePosition.x, Input.mousePosition.y, 15)));
}
}
}