添加相机输出图片
添加相机，创建GetImage脚本：
思路是创建相机对象，建立事件，按下空格键即将所看到的画面渲染到目标纹理，然后选择保存路径，代码如下：
代码语言：javascript复制using UnityEngine;
using System.Collections;
using System.IO;
// 获取副相机图像，空格键截取
public class GetImage : MonoBehaviour
{
public Camera mainCam; //待截图的目标摄像机
RenderTexture rt; //声明一个截图时候用的中间变量
Texture2D t2d; //目标纹理
int num = 0; //截图计数
void Start()
{
t2d = new Texture2D(400, 300, TextureFormat.RGB24, false);
rt = new RenderTexture(400, 300, 24);
mainCam.targetTexture = rt;
}
void Update()
{
//按下空格键来截图
if (Input.GetKeyDown(KeyCode.Space))
{
//截图到t2d中
RenderTexture.active = rt;
t2d.ReadPixels(new Rect(0, 0, rt.width, rt.height), 0, 0);
t2d.Apply();
RenderTexture.active = null;
//将图片保存起来
byte[] byt = t2d.EncodeToJPG(); //转成jpg格式
File.WriteAllBytes(Application.dataPath "//" num.ToString() ".jpg", byt); //文件写入
Debug.Log("当前截图序号为：" num.ToString());
num ; //文件序号
}
}
}相机跟随移动
不过，以上相机是固定的，也就只能截图一个位置的图片，我们想要的效果是跟随小车，模拟采集小车相机的画面。
参考这篇，采用固定摄像机方法。
创建 TheThirdPersonCamera脚本并添加到副相机上：
思路是获取Player的位置，然后在此基础上确定相机位置，来实时跟随获取图像，脚本如下：
代码语言：javascript复制using UnityEngine;
using System.Collections;
/// <summary>
/// Third person camera.
/// </summary>
public class TheThirdPersonCamera : MonoBehaviour
{
public float distanceAway = 10f;
public float distanceUp = 10f;
public float smooth = 2f; // how smooth the camera movement is
private Vector3 m_TargetPosition; // the position the camera is trying to be in)
Transform follow; //the position of Player
void Start()
{
follow = GameObject.FindWithTag("Player").transform;
}
void LateUpdate()
{
// setting the target position to be the correct offset from the
m_TargetPosition = follow.position Vector3.up * distanceUp follow.forward * distanceAway;
//Debug.Log(follow.position);
//Debug.Log(follow.forward);
// 相机移动更平滑
transform.position = Vector3.Lerp(transform.position, m_TargetPosition, Time.deltaTime * smooth);
// make sure the camera is looking the right way!
transform.LookAt(follow);
}
}最后，截取到的图像如下：
