Unity之一天一个技术点（十四）---通过鼠标控制镜头绕着某物体旋转

using UnityEngine;

using System.Collections;

/**

* 备注：本脚本必须赋予主镜头

*/

public class CameraRotateAround : MonoBehaviour {

public Transform target;//主相机要围绕其旋转的物体

public float distance = 7.0f;//主相机与目标物体之间的距离

private float eulerAngles_x;

private float eulerAngles_y;

//水平滚动相关

public int distanceMax = 10;//主相机与目标物体之间的最大距离

public int distanceMin = 3;//主相机与目标物体之间的最小距离

public float xSpeed = 70.0f;//主相机水平方向旋转速度

//垂直滚动相关

public int yMaxLimit = 60;//最大y（单位是角度）

public int yMinLimit = -10;//最小y（单位是角度）

public float ySpeed = 70.0f;//主相机纵向旋转速度

//滚轮相关

public float MouseScrollWheelSensitivity = 1.0f;//鼠标滚轮灵敏度（备注：鼠标滚轮滚动后将调整相机与目标物体之间的间隔）

public LayerMask CollisionLayerMask;

// Use this for initialization

void Start () {

Vector3 eulerAngles = this.transform.eulerAngles;//当前物体的欧拉角

this.eulerAngles_x = eulerAngles.y;

this.eulerAngles_y = eulerAngles.x;

}

// Update is called once per frame

void LateUpdate()

{

if (this.target != null)

{

this.eulerAngles_x += ((Input.GetAxis("Mouse X") * this.xSpeed) * this.distance) * 0.02f;

this.eulerAngles_y -= (Input.GetAxis("Mouse Y") * this.ySpeed) * 0.02f;

this.eulerAngles_y = ClampAngle(this.eulerAngles_y, (float)this.yMinLimit, (float)this.yMaxLimit);

Quaternion quaternion = Quaternion.Euler(this.eulerAngles_y, this.eulerAngles_x, (float)0);

this.distance = Mathf.Clamp(this.distance - (Input.GetAxis("Mouse ScrollWheel") * MouseScrollWheelSensitivity), (float)this.distanceMin, (float)this.distanceMax);

//从目标物体处，到当前脚本所依附的对象（主相机）发射一个射线，如果中间有物体阻隔，则更改this.distance（这样做的目的是为了不被挡住）

RaycastHit hitInfo = new RaycastHit();

if (Physics.Linecast(this.target.position, this.transform.position, out hitInfo, this.CollisionLayerMask))

{

this.distance = hitInfo.distance-0.05f;

}

Vector3 vector = ((Vector3)(quaternion * new Vector3((float)0, (float)0, -this.distance))) + this.target.position;

//更改主相机的旋转角度和位置

this.transform.rotation = quaternion;

this.transform.position = vector;

}

}

//把角度限制到给定范围内

public float ClampAngle(float angle, float min, float max)

{

while (angle < -360)

{

angle += 360;

}

while (angle > 360)

{

angle -= 360;

}

return Mathf.Clamp(angle, min, max);

}

}