c# 鼠标操作摄像机脚本

using UnityEngine;
using System.Collections;


public class MouseControl : MonoBehaviour
{

//目标物体
public Transform target;
private int MouseWheelSensitivity = 1; //放大倍数的快慢
private int MouseZoomMin = 1; //最小倍数
private int MouseZoomMax = 5; //最大倍数
//默认距离
private float normalDistance = 3;


private Vector3 normalized;

//拖拽的移动速度
private float xSpeed = 250.0f;
private float ySpeed = 120.0f;

//拖拽的高度限制
private int yMinLimit = -20;
private int yMaxLimit = 80;

//角度
private float x = 0.0f;
private float y = 0.0f;

//记录目标物体的坐标
private Vector3 screenPoint;
private Vector3 offset;

//围绕x旋转30°
private Quaternion rotation = Quaternion.Euler(new Vector3(30f, 0f, 0f));

//目标的3D坐标
private Vector3 CameraTarget;

//打印欧拉角:绕各个轴旋转的角度，顺时针为正方向
public void Awake()
{
print(transform.eulerAngles.x);
print(transform.eulerAngles.y);
print(transform.eulerAngles.z);
}

void Start()
{
//找到目标飞机的3d坐标
CameraTarget = target.position;

//目标飞机的z-3，距离摄像机更近了
float z = target.transform.position.z - normalDistance;
//给当前相机给定位，现在的3D坐标乘以30°
transform.position = rotation * new Vector3(transform.position.x, transform.position.y, z);

//将视角转向物体
transform.LookAt(target);

//记录各个轴偏离的角度
var angles = transform.eulerAngles;
x = angles.y;
y = angles.x;
}

// void OnGUI()
// {
// GUI.Label(new Rect(10,10,300,30),"左击:旋转；滚轮：缩放；中击：拖拽");
// }
//
void Update()
{
//如果左击了，旋转
if (Input.GetMouseButton(0))
{
x += Input.GetAxis("Mouse X") * xSpeed * 0.02f;
y -= Input.GetAxis("Mouse Y") * ySpeed * 0.02f;

y = ClampAngle(y, yMinLimit, yMaxLimit);

var rotation = Quaternion.Euler(y, x, 0);
var position = rotation * new Vector3(0.0f, 0.0f, -normalDistance) + CameraTarget;

transform.rotation = rotation;
transform.position = position;

}
//滚轮缩放
else if (Input.GetAxis("Mouse ScrollWheel") != 0)
{
//摄像机3d坐标-物体的3d坐标
normalized = (transform.position - CameraTarget).normalized;

if (normalDistance >= MouseZoomMin && normalDistance <= MouseZoomMax)
{
normalDistance -= Input.GetAxis("Mouse ScrollWheel") * MouseWheelSensitivity;
}
if (normalDistance < MouseZoomMin)
{
normalDistance = MouseZoomMin;
}
if (normalDistance > MouseZoomMax)
{
normalDistance = MouseZoomMax;
}
//改变摄像机的远近
transform.position = normalized * normalDistance;
}
//案件按下 记录鼠标的
else if (Input.GetMouseButtonDown(2))
{
//将目标物体的坐标转化成平面坐标
screenPoint = Camera.main.WorldToScreenPoint(target.transform.position);
//计算鼠标的3维坐标跟物体的3维坐标的差值
offset = target.transform.position - Camera.main.ScreenToWorldPoint(new Vector3(Input.mousePosition.x, Input.mousePosition.y, screenPoint.z));
}

//中键拖拽，改变飞机的坐标，每帧调用
if (Input.GetMouseButton(2))
{
//鼠标的平面坐标
Vector3 curScreenPoint = new Vector3(Input.mousePosition.x, Input.mousePosition.y, screenPoint.z);
//鼠标转移的3d空间坐标值
Vector3 curPosition = Camera.main.ScreenToWorldPoint(curScreenPoint) + offset;
//改变鼠标的3D空间坐标
target.transform.position = curPosition;
}
//朝向，每动一帧都要改变朝向
transform.LookAt(CameraTarget);
}

//控制旋转的角度，如果旋转的角度大于360或者小于360都要加上或者减去对应的角度
static float ClampAngle(float angle, float min, float max)
{
if (angle < -360)
angle += 360;
if (angle > 360)
angle -= 360;
return Mathf.Clamp(angle, min, max);
}
}