【Unity3D】鼠标滚动拉近模型、鼠标右键旋转模型、鼠标中键拖拽模型 764424567

using UnityEngine;
using System.Collections;
 
public class Script_07_11 : MonoBehaviour
{
 
public Transform target;
private int MouseWheelSensitivity = 1;
private int MouseZoomMin = 1;
private int MouseZoomMax = 5;
private float normalDistance = 3;
 
private Vector3 normalized;
 
private float xSpeed = 250.0f;
private float ySpeed = 120.0f;
 
private int yMinLimit = -20;
private int yMaxLimit = 80;
 
private float x = 0.0f;
private float y = 0.0f;
 
private Vector3 screenPoint;
private Vector3 offset;
 
private Quaternion rotation = Quaternion.Euler(new Vector3(30f,0f,0f));
private Vector3 CameraTarget;
void Start ()
{
 
	CameraTarget = target.position;
 
	float z = target.transform.position.z - normalDistance;
	transform.position = rotation * new Vector3(transform.position.x,transform.position.y,z);
 
	transform.LookAt(target);
 
	var angles = transform.eulerAngles;
    x = angles.y;
    y = angles.x;
}
 
void Update ()
{
 
	if(Input.GetMouseButton(1))
	{
	     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;
 
	}
	else if (Input.GetAxis(“Mouse ScrollWheel”) != 0)
	{
	    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;
	}
	
	transform.position =    normalized * normalDistance;
 
	}
	else if(Input.GetMouseButtonDown(2))
	{
	     screenPoint = Camera.main.WorldToScreenPoint(target.transform.position);
		offset = target.transform.position - Camera.main.ScreenToWorldPoint(new        Vector3(Input.mousePosition.x, Input.mousePosition.y, screenPoint.z));
	}
 
	if(Input.GetMouseButton(2))
	{
		Vector3 curScreenPoint = new Vector3(Input.mousePosition.x, Input.mousePosition.y, screenPoint.z);
 
		Vector3 curPosition = Camera.main.ScreenToWorldPoint(curScreenPoint) + offset;
		target.transform.position = curPosition;
	}
	transform.LookAt(CameraTarget);
 
}
 
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);
}