Unity 鼠标与键盘控制相机移动与旋转

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


 enum MouseButtonDown
	{
		MBD_LEFT = 0,
		MBD_RIGHT,
		MBD_MIDDLE,
	};

	public class HYQCameraController : MonoBehaviour
	{
		// [SerializeField]
		private Vector3 focus = Vector3.zero;
		// [SerializeField]
		private GameObject focusObj = null;

		public bool showInstWindow = true;

		private Vector3 oldPos;

		[Tooltip("缩放系数")]
		[SerializeField] private float ScrollSpeed = 0.9f;
		[Tooltip("移动速度")]
		[SerializeField] private float MoveSpeed = 0.7f;
		[Tooltip("相机旋转速度")]
		[SerializeField] private float RotaSpeed = 0.25f;

		private float KeyRotaCameraSpeed=40f;

		private float inputH,inputV;
		private bool CanMove = true;
		void setupFocusObject(string name)
		{
			GameObject obj = this.focusObj = new GameObject(name);
			obj.transform.position = this.focus;
			obj.transform.LookAt(this.transform.position);

			return;
		}

		void Start ()
		{
			if (this.focusObj == null)
				this.setupFocusObject("CameraFocusObject");

			Transform trans = this.transform;
			transform.parent = this.focusObj.transform;

			trans.LookAt(this.focus);
			return;
		}
	
		void Update ()
		{
			this.mouseEvent();


			

			this.KeyBoardController();
			
			if(Input.GetKey("escape")){
				Application.Quit();
			}
			
			return;
		}
# region Mouse Controller
		void mouseEvent()
		{
			float delta = Input.GetAxis("Mouse ScrollWheel") * ScrollSpeed;
			if (delta != 0.0f)
				this.mouseWheelEvent(-delta);

			if (Input.GetMouseButtonDown((int)MouseButtonDown.MBD_LEFT) ||
				Input.GetMouseButtonDown((int)MouseButtonDown.MBD_MIDDLE) ||
				Input.GetMouseButtonDown((int)MouseButtonDown.MBD_RIGHT))
				this.oldPos = Input.mousePosition;

			this.mouseDragEvent(Input.mousePosition);

			return;
		}

		void mouseDragEvent(Vector3 mousePos)
		{
			//当按下了左，中，右键时先记录按下那一刻鼠标的位置，储存为oldPos，然后执行拖动鼠标移动相机的操作
			Vector3 diff = mousePos - oldPos;

			if(Input.GetMouseButton((int)MouseButtonDown.MBD_LEFT))
			{
				//Operation for Mac : "Left Alt + Left Command + LMB Drag" is Track
				if(Input.GetKey(KeyCode.LeftAlt) && Input.GetKey(KeyCode.LeftCommand))
				{
					if (diff.magnitude > Vector3.kEpsilon)
						this.cameraTranslate(-diff / 100.0f);
				}
				//Operation for Mac : "Left Alt + LMB Drag" is Tumble
				else if (Input.GetKey(KeyCode.LeftAlt))
				{
					if (diff.magnitude > Vector3.kEpsilon)
						this.cameraRotate(new Vector3(diff.y, diff.x, 0.0f) );
				}
				//Only "LMB Drag" is no action.
			}
			//Track
			else if (Input.GetMouseButton((int)MouseButtonDown.MBD_MIDDLE))
			{
				if (diff.magnitude > Vector3.kEpsilon)
					this.cameraTranslate(-diff / 100.0f);
			}
			//Tumble
			else if (Input.GetMouseButton((int)MouseButtonDown.MBD_RIGHT))
			{
				if (diff.magnitude > Vector3.kEpsilon)
					this.cameraRotate(new Vector3(diff.y, diff.x, 0.0f));
			}
				
			this.oldPos = mousePos;	

			return;
		}

		//Dolly
		public void mouseWheelEvent(float delta)
		{
			Vector3 focusToPosition = this.transform.position - this.focus;

			Vector3 post = focusToPosition * (1.0f + delta);

			if (post.magnitude > 0.01)
				this.transform.position = this.focus + post;

			return;
		}

		void cameraTranslate(Vector3 vec)
		{
			Transform focusTrans = this.focusObj.transform;

			vec.x *= -1;

			focusTrans.Translate(Vector3.right * vec.x * MoveSpeed );
			focusTrans.Translate(Vector3.up * vec.y * MoveSpeed );
			//如果没有按下shift键则开启前台移动，否则关闭前台移动
			if (!(Input.GetKey(KeyCode.LeftShift)|| Input.GetKey(KeyCode.RightShift))){
				focusTrans.Translate(Vector3.forward * vec.z *MoveSpeed);
			}
			

			this.focus = focusTrans.position;

			return;
		}

		public void cameraRotate(Vector3 eulerAngle)
		{
			//Use Quaternion to prevent rotation flips on XY plane
			Quaternion q = Quaternion.identity;
 
			Transform focusTrans = this.focusObj.transform;
			focusTrans.localEulerAngles = focusTrans.localEulerAngles + (eulerAngle *  RotaSpeed);

			//Change this.transform.LookAt(this.focus) to q.SetLookRotation(this.focus)
			q.SetLookRotation (this.focus ) ;

			return;
		}

		#endregion



# region KeyCode Controller
void KeyBoardController(){

	inputH = Input.GetAxis("Horizontal") * Time.deltaTime *MoveSpeed;
	inputV = Input.GetAxis("Vertical") * Time.deltaTime *  MoveSpeed;
	IsCanMove();	//检测是否可以移动
	if (CanMove){
		//左右平移
		if(inputH != 0){
			// transform.Translate(new Vector3(inputH,0,0),Space.Self);
			this.cameraTranslate(new Vector3(inputH,0,0));
		}

		//前后平移
		if(inputV != 0 ){
			// transform.Translate(new Vector3(0,0,inputV),Space.Self);
			this.cameraTranslate(new Vector3(0,0,-inputV));
		}
		//上下平移
		if( Input.GetKey(KeyCode.LeftShift) || Input.GetKey(KeyCode.RightShift) && inputV != 0 ){
			// transform.Translate(new Vector3(0,inputV,0),Space.Self);
			this.cameraTranslate(new Vector3(0,inputV,0));
		}

	}
	

	//旋转相机

	//如果按住Ctrl +左右键，则相机左右旋转

	if((Input.GetKey(KeyCode.LeftControl) || Input.GetKey(KeyCode.RightControl)) && inputH != 0){

		
		this.cameraRotate(new Vector3(inputV,inputH,0) * KeyRotaCameraSpeed);

	}

	if((Input.GetKey(KeyCode.LeftControl) || Input.GetKey(KeyCode.RightControl)) && inputV != 0){
			
			this.cameraRotate(new Vector3(inputV,inputH,0) * KeyRotaCameraSpeed);

	}
}

void IsCanMove(){
	if(Input.GetKey(KeyCode.LeftControl) || Input.GetKey(KeyCode.RightControl)){
		CanMove = false;
	}else{
		CanMove = true;
	}
}

#endregion
	}