总结圣典中操作物体任意方向旋转的三种方法

using UnityEngine;
using System.Collections;

public class Rotate1 : MonoBehaviour {

private Transform hitTransform;

// Use this for initialization
void Start () {

}

// Update is called once per frame
void Update () {
if (Input.GetMouseButtonDown(0))
{
// 射线检测，单击鼠标是否单击到一个物体上
RaycastHit hit;
Ray mouseray = Camera.main.ScreenPointToRay(Input.mousePosition);
if (Physics.Raycast(mouseray, out hit))
{
hitTransform = hit.transform;
}
}
else if(Input.GetMouseButtonUp(0))
{
hitTransform = null;
}

if (hitTransform)
{
Matrix4x4 localmatrix = hitTransform.worldToLocalMatrix;
// MultiplyVector() 通过这个矩阵变换方向
Vector3 vUp = localmatrix.MultiplyVector(new Vector3(0, 1, 0));
Vector3 vRight = -localmatrix.MultiplyVector(new Vector3(1, 0, 0));

// Quaternion.AngleAxis 角轴
//绕axis轴旋转angle，创建一个旋转。
//设置变换的旋转，绕y轴旋转30度
// for example transform.rotation = Quaternion.AngleAxis(30, Vector3.up);
float fMoveX = -Input.GetAxis("Mouse X") * Time.deltaTime * 200.0f;
Quaternion rotationX = Quaternion.AngleAxis(fMoveX, vUp);
hitTransform.localRotation *= rotationX;

float fMoveY = -Input.GetAxis("Mouse Y") * Time.deltaTime * 200f;
Quaternion rotationY = Quaternion.AngleAxis(fMoveY, vRight);
hitTransform.localRotation *= rotationY;
}
}
}

using UnityEngine;
using System.Collections;

public class Rotate2 : MonoBehaviour {

// Use this for initialization
void Start () {

}

// Update is called once per frame
void Update () {

}

void OnMouseDrag()
{
this.transform.Rotate(new Vector3(Input.GetAxis("Mouse Y"), -Input.GetAxis("Mouse X"), 0) * 6f, Space.World);
}
}

using UnityEngine;
using System.Collections;

public class Rotate3 : MonoBehaviour {

private bool onDrag = false;

private float axisX;
private float axisY;

public float speed = 6f;
private float tempSpeed;

// Use this for initialization
void Start () {

}

// Update is called once per frame

void OnMouseDrag()
{
onDrag = true;
axisX = Input.GetAxis("Mouse X");
axisY = Input.GetAxis("Mouse Y");
}
void Update () {
transform.Rotate(new Vector3(axisY, -axisX, 0) * Rigid(), Space.World);
if (!Input.GetMouseButtonDown(0))
{
onDrag = false;
}
}

float Rigid()
{
if (onDrag)
{
if (tempSpeed < speed)
{
tempSpeed += speed * Time.deltaTime * 5;
}
else
tempSpeed = speed;
}else
{
if (tempSpeed > 0)
tempSpeed -= speed * Time.deltaTime;
else
tempSpeed = 0;
}
//
return tempSpeed;
}
}

/*
*  使物体自动旋转，鼠标能够360°拖转物体，托转物体的时候，
*  自动旋转停止，同时滚轮实现物体的缩放功能
*
*/

using UnityEngine;
using System.Collections;

public class ZoomAndDrag : MonoBehaviour {

public Camera MainCamera;

private bool RotationOnly;
private float normalDistance;   // 设置摄像机的景深数值
private float ZoomMin;          // 滚轮的最小值
private float ZoomMax;          // 滚轮的最大值
private float MouseWheelSencitivity = 10.0f;    //鼠标灵敏度，就是缩放速度的快慢

private float axisX;
private float axisY;
public float speed = 6f;
private float tempSpeed;

// Use this for initialization
void Start () {
normalDistance = 50.0f;
RotationOnly = true;
ZoomMax = 100f;
ZoomMin = 20f;
}

// Update is called once per frame
void Update () {
Rotation();
Zoom();
transform.Rotate(new Vector3(axisY, -axisX, 0) * Rigid(), Space.World);  // 物体旋转
}

// //自动旋转物体的方法，放在Update中调用
void Rotation()
{
if (RotationOnly)
{
gameObject.transform.Rotate(Vector3.up * Time.deltaTime * 10);
}
}

//*鼠标滚轮缩放物体的方法
void Zoom()
{
if (Input.GetAxis("Mouse ScrollWheel") != 0)
{
if(normalDistance >= ZoomMin && normalDistance <= ZoomMax)
normalDistance -= Input.GetAxis("Mouse ScrollWheel") * MouseWheelSencitivity;

if (normalDistance < ZoomMin)
normalDistance = ZoomMin;
if (normalDistance > ZoomMax)
normalDistance = ZoomMax;

MainCamera.fieldOfView = normalDistance;
}
}

/// <summary>
/// 鼠标左键控制物体360°旋转 + 惯性
/// </summary>
/// <returns></returns>
float Rigid()
{

if (Input.GetMouseButton(0))
{
print("nishishui");
RotationOnly = false;   //当鼠标按下的时候，停止自动旋转
axisX = Input.GetAxis("Mouse X");
axisY = Input.GetAxis("Mouse Y");
if (tempSpeed < speed)
tempSpeed += speed * Time.deltaTime * 5;
else
tempSpeed = speed;
}
else
{
RotationOnly = true;     //当鼠标没有按下的时候，恢复自动旋转
if (tempSpeed > 0)
tempSpeed -= speed * Time.deltaTime;
else
tempSpeed = 0;
}
return tempSpeed;
}
}