方法一:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class CamerMoveTest2 : MonoBehaviour {

    public Transform target;//獲取旋轉(zhuǎn)目標(biāo)
        public float speed = 0.5f;

    private void Update()
    {
        if (Input.GetMouseButton(0))
        {
            camerarotate();
        }
       
        camerazoom();
    }

    private void camerarotate() //攝像機(jī)圍繞目標(biāo)旋轉(zhuǎn)操作
    {
        transform.RotateAround(target.position, Vector3.up, speed*Time.deltaTime); //攝像機(jī)圍繞目標(biāo)旋轉(zhuǎn)
        var mouse_x = Input.GetAxis("Mouse X");//獲取鼠標(biāo)X軸移動(dòng)
        var mouse_y = -Input.GetAxis("Mouse Y");//獲取鼠標(biāo)Y軸移動(dòng)

        if (Input.GetKey(KeyCode.Mouse1))
        {
            transform.Translate(Vector3.left*(mouse_x*15f)*Time.deltaTime);
            transform.Translate(Vector3.up*(mouse_y*15f)*Time.deltaTime);
        }
        if (Input.GetKey(KeyCode.Mouse0))
        {
            transform.RotateAround(target.transform.position, Vector3.up, mouse_x*5);
            transform.RotateAround(target.transform.position, transform.right, mouse_y*5);
        }
    }

    private void camerazoom() //攝像機(jī)滾輪縮放
    {
        if (Input.GetAxis("Mouse ScrollWheel") > 0)
            transform.Translate(Vector3.forward*0.5f);
  
        if (Input.GetAxis("Mouse ScrollWheel") < 0)
            transform.Translate(Vector3.forward*-0.5f);
    }
}

方法二:

using System.Collections;  
using System.Collections.Generic;  
using UnityEngine;  
  
public class CameraMove : MonoBehaviour  
{  
    //攝像機(jī)距離  
    public float distance = 10.0f;  
    //縮放系數(shù)  
    public float scaleFactor = 1f;  
  
  
    public float maxDistance = 30f;  
    public float minDistance = 5f;  
  
  
    //記錄上一次手機(jī)觸摸位置判斷用戶是在左放大還是縮小手勢(shì)  
    private Vector2 oldPosition1;  
    private Vector2 oldPosition2;  
  
  
    private Vector2 lastSingleTouchPosition;  
  
    private Vector3 m_CameraOffset;  
    private Camera m_Camera;  
  
    public bool useMouse = true;  
  
    //定義攝像機(jī)可以活動(dòng)的范圍  
    public float xMin = -100;  
    public float xMax = 100;  
    public float zMin = -100;  
    public float zMax = 100;  
  
    //這個(gè)變量用來記錄單指雙指的變換  
    private bool m_IsSingleFinger;  
  
    //初始化游戲信息設(shè)置  
    void Start()  
    {  
        m_Camera = this.GetComponent<Camera>();  
        m_CameraOffset = m_Camera.transform.position;  
    }  
  
    void Update()  
    {  
        //判斷觸摸數(shù)量為單點(diǎn)觸摸  
        if (Input.touchCount == 1)  
        {  
            if (Input.GetTouch(0).phase == TouchPhase.Began || !m_IsSingleFinger)  
            {  
                //在開始觸摸或者從兩字手指放開回來的時(shí)候記錄一下觸摸的位置  
                lastSingleTouchPosition = Input.GetTouch(0).position;  
            }  
            if (Input.GetTouch(0).phase == TouchPhase.Moved)  
            {  
                MoveCamera(Input.GetTouch(0).position);  
            }  
            m_IsSingleFinger = true;  
  
        }  
        else if (Input.touchCount > 1)  
        {  
            //當(dāng)從單指觸摸進(jìn)入多指觸摸的時(shí)候,記錄一下觸摸的位置  
            //保證計(jì)算縮放都是從兩指手指觸碰開始的  
            if (m_IsSingleFinger)  
            {  
                oldPosition1 = Input.GetTouch(0).position;  
                oldPosition2 = Input.GetTouch(1).position;  
            }  
  
            if (Input.GetTouch(0).phase == TouchPhase.Moved || Input.GetTouch(1).phase == TouchPhase.Moved)  
            {  
                ScaleCamera();  
            }  
  
            m_IsSingleFinger = false;  
        }  
  
  
        //用鼠標(biāo)的  
        if (useMouse)  
        {  
            distance -= Input.GetAxis("Mouse ScrollWheel") * scaleFactor;  
            distance = Mathf.Clamp(distance, minDistance, maxDistance);  
            if (Input.GetMouseButtonDown(0))  
            {  
                lastSingleTouchPosition = Input.mousePosition;  
                Debug.Log("GetMouseButtonDown:" + lastSingleTouchPosition);  
            }  
            if (Input.GetMouseButton(0))  
            {  
                MoveCamera(Input.mousePosition);  
            }  
        } 
    }  
  
    /// <summary>  
    /// 觸摸縮放攝像頭  
    /// </summary>  
    private void ScaleCamera()  
    {  
        //計(jì)算出當(dāng)前兩點(diǎn)觸摸點(diǎn)的位置  
        var tempPosition1 = Input.GetTouch(0).position;  
        var tempPosition2 = Input.GetTouch(1).position;  
  
  
        float currentTouchDistance = Vector3.Distance(tempPosition1, tempPosition2);  
        float lastTouchDistance = Vector3.Distance(oldPosition1, oldPosition2);  
  
        //計(jì)算上次和這次雙指觸摸之間的距離差距  
        //然后去更改攝像機(jī)的距離  
        distance -= (currentTouchDistance - lastTouchDistance) * scaleFactor * Time.deltaTime;  
  
  
        //把距離限制住在min和max之間  
        distance = Mathf.Clamp(distance, minDistance, maxDistance);  
  
  
        //備份上一次觸摸點(diǎn)的位置，用于對(duì)比  
        oldPosition1 = tempPosition1;  
        oldPosition2 = tempPosition2;  
    }  
  
  
    //Update方法一旦調(diào)用結(jié)束以后進(jìn)入這里算出重置攝像機(jī)的位置  
    private void LateUpdate()  
    {  
        var position = m_CameraOffset + m_Camera.transform.forward * -distance;  
        m_Camera.transform.position = position;  
    }  
  
  
    private void MoveCamera(Vector3 scenePos)  
    {  
        Vector3 lastTouchPostion = m_Camera.ScreenToWorldPoint(new Vector3(lastSingleTouchPosition.x, lastSingleTouchPosition.y, -1));  
        Vector3 currentTouchPosition = m_Camera.ScreenToWorldPoint(new Vector3(scenePos.x, scenePos.y, -1));  
  
        Vector3 v = currentTouchPosition - lastTouchPostion;  
        m_CameraOffset += new Vector3(v.x, 0, v.z) * m_Camera.transform.position.y;  
  
        //把攝像機(jī)的位置控制在范圍內(nèi)  
        m_CameraOffset = new Vector3(Mathf.Clamp(m_CameraOffset.x, xMin, xMax), m_CameraOffset.y, Mathf.Clamp(m_CameraOffset.z, zMin, zMax));  
        //Debug.Log(lastTouchPostion + "|" + currentTouchPosition + "|" + v);  
        lastSingleTouchPosition = scenePos;  
    }  
}