目录

1.实现思路

2.记录小球生成时间

3.设置小球

4.移动拖尾，动态计算

5.测试

1.实现思路

unity自带组件TrailRenderer不带Collider，如果想实现碰撞触发功能怎么实现呢

在拖尾移动时生成小球，用小球colliderr当做触发器，动态计算小球的存在时间，超时后销毁

2.记录小球生成时间

Point.cs记录小球生成时间，OnTriggerEnter内做触发处理

挂载到小球预设体上面

using UnityEngine;public class Point : MonoBehaviour
{public float createTime;void OnTriggerEnter(Collider coll){Debug.Log("Do something");if (coll.tag == "Fruit"){Debug.Log("Trail collider  Enter");//coll.GetComponent<Fruit>().OnHirt(50);}}
}

3.设置小球

勾选IsTrigger，变为触发器

取消勾选MeshRenderer，不显示小球；测试时可以显示，测试完成后取消勾选

4.移动拖尾，动态计算

本文用到了对象池，不用自行修改为GameObject.Instantiate、Destory

using UnityEngine;
using System.Collections.Generic;
using UnityEditor;public class DrawTrailCollider : MonoBehaviour
{//拖尾特效持续时长public static float overTime = 0.2f;public List<Point> pointList = new List<Point>();private int maxPoints = 500;public int minPixelMove = 5;    // Must move at least this many pixels per sample for a new segment to be recordedpublic float distanceFromCamera = 5.0f;private Vector3 previousPosition;private int sqrMinPixelMove;private bool canDraw = false;void Start(){sqrMinPixelMove = minPixelMove * minPixelMove;}void Update(){if (Input.GetKeyDown(KeyCode.Space))//调试{EditorApplication.isPaused = true;}if (Input.GetMouseButtonDown(0)){previousPosition = Input.mousePosition;AddPoint(GetMousePos());canDraw = true;}else if (Input.GetMouseButton(0) && (Input.mousePosition - previousPosition).sqrMagnitude > sqrMinPixelMove && canDraw){previousPosition = Input.mousePosition;AddPoint(GetMousePos());CheckOverTime();if (pointList.Count >= maxPoints){canDraw = false;}}else{if (pointList.Count > 0){CheckOverTime();}}}Vector3 GetMousePos(){var p = Input.mousePosition;p.z = distanceFromCamera;//Vector3 pos = XHSDK.XHSDKManager.Instance.mainCam.ScreenToWorldPoint(p);Vector3 pos = Camera.main.ScreenToWorldPoint(p);return pos;}/// <summary>/// 增加顶点/// </summary>public void AddPoint(Vector3 pos){GameObject go = ObjectPool._instance.GetObject("Point", pos, Quaternion.identity);Point point = go.GetComponent<Point>();point.createTime = Time.realtimeSinceStartup;pointList.Add(point);}void CheckOverTime(){//移除超时的点for (int i = 0; i < pointList.Count; i++){            if (Time.realtimeSinceStartup - pointList[i].createTime > overTime){ObjectPool._instance.SetObjectToPool(pointList[i].gameObject);pointList.Remove(pointList[i]);i--;}}}
}

5.测试

测试基本可以达到想要的效果