在制作3d射击类游戏中，会遇到跟随角色的摄像机会穿透墙壁导致视野不佳情况，下面，介绍一下具体的解决方法。
我们需要用到的原理就是unity中射击线函数。具体的原理是，从相机的跟随点向相机的方向发射一条距离为默认距离的相机射线，如该射线能检测到墙体，则相机向前移动。
下面开始发源码，
注：使用的时候要将墙体加碰撞组件，并且设置其tag为"Cube"
/** 相机跟随玩家移动，并控制玩家转向，适合第三人称游戏*/using CoverShooter;using System.Collections;using System.Collections.Generic;using UnityEngine;public class CameraMoveWithPlayer : MonoBehaviour{[Header("相机距离")]public float freeDistance = 2;[Header("相机最近距离")]public float minDistance = 0.5f;[Header("相机最远距离")]public float maxDistance = 3;[Header("是否可控制相机距离(鼠标中键)")]public bool canControlDistance = true;[Header("更改相机距离的速度")]public float distanceSpeed = 1;[Header("视角灵敏度")]public float rotateSpeed = 1;[Header("物体转向插值(灵敏度,取值为0到1)")]public float TargetBodyRotateLerp = 0.3f;[Header("需要转向的物体")]public GameObject TargetBody;//此脚本能操作转向的物体[Header("相机焦点物体")]public GameObject CameraPivot;//相机焦点物体 [Header("是否可控制物体转向")]public bool CanControlDirection = true;//相机的距离比例，该向量防止相机撞墙private float proportion = 1f;private Vector3 CubePosition;private Vector3 m_rayDirection;private RaycastHit m_hit;Transform m_transform;private Transform target;private Ray m_ray;private Vector3 offset;//偏移private RaycastHit[] _hits = new RaycastHit[64]; // Start is called before the first frame updateprivate void Awake(){m_transform = transform;CubePosition = m_transform.position;target = TargetBody.transform;}void Start(){Cursor.lockState = CursorLockMode.Locked;//获取目标与相机之间的差值offset = transform.position - CameraPivot.transform.position;}void FreeCamera(){if (CanControlDirection)//控制角色方向开关{Quaternion TargetBodyCurrentRotation = TargetBody.transform.rotation;TargetBody.transform.rotation = Quaternion.Lerp(TargetBodyCurrentRotation, Quaternion.Euler(new Vector3(TargetBody.transform.localEulerAngles.x, transform.localEulerAngles.y, TargetBody.transform.localEulerAngles.z)), TargetBodyRotateLerp);}//控制相机随鼠标的旋转float inputY = Input.GetAxis("Mouse Y");float inputX = Input.GetAxis("Mouse X");transform.RotateAround(CameraPivot.transform.position, Vector3.up, rotateSpeed * inputX);transform.RotateAround(CameraPivot.transform.position, TargetBody.transform.right, -rotateSpeed * inputY);transform.LookAt(CameraPivot.transform.position);//旋转之后以上方向发生了变化,需要更新方向向量offset = transform.position - CameraPivot.transform.position;offset = offset.normalized * freeDistance * proportion;//更新相机的位置transform.position = CameraPivot.transform.position + offset;}private void PreventThroughWall(){//相机根据物体的位置发射一条反向的的射线m_rayDirection = m_transform.position - target.position;//将该向量规范化，即向量的模为1m_rayDirection.Normalize();//从相机的跟随目标向相机发射一条距离为相机默认距离的向量m_ray = new Ray(target.position, m_rayDirection * freeDistance);//如果可以检测到碰撞物体，并且碰撞物体的tag未"Cube"if (Physics.Raycast(m_ray, out m_hit) && m_hit.collider.tag.Equals("Cube")){//获取射击点的坐标CubePosition = new Vector3(m_hit.point.x, m_hit.point.y, m_hit.point.z);//获取射击点与检测点的距离float distance = Vector3.Distance(CubePosition, target.position);//更新相机的距离比例proportion = Mathf.Min(1.0f, distance / freeDistance);}else{proportion = 1.0f;offset = offset.normalized * freeDistance;transform.position = Vector3.Lerp(transform.position, CameraPivot.transform.position + offset, 1f);//更新位置if (canControlDistance){freeDistance -= Input.GetAxis("Mouse ScrollWheel") * TargetBodyRotateLerp * Time.deltaTime;freeDistance = Mathf.Clamp(freeDistance, minDistance, maxDistance);}}}// Update is called once per framevoid FixedUpdate(){PreventThroughWall();FreeCamera();}// Update is called once per framevoid Update(){//PreventThroughWall();}}
