CharmViewer/Assets/MouseControlModel.cs

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

// modyified from https://blog.csdn.net/q764424567/article/details/90238382 2023.03.13
public class MouseControlModel : MonoBehaviour
{
    
    public int yMinLimit = -20;
    public int yMaxLimit = 80;
    
    public float xSpeed = 250.0f;
    public float ySpeed = 120.0f;
    
    private float x = 0.0f;
    private float y = 0.0f;

    Vector3 previousPos;
    bool isMouseDown = false;

    void Update()
    {
        if (Input.GetMouseButton(0))
        {
            Vector3 pos = Camera.main.ScreenToWorldPoint(new Vector3(Input.mousePosition.x, Input.mousePosition.y, 30));
            if (!isMouseDown)
            {
                isMouseDown = true;
            }
            else
            {
                transform.position += (pos - previousPos);
            }
            previousPos = pos;
        }
        else 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);
            Quaternion rotation = Quaternion.Euler(y, x, 0);
            transform.rotation = rotation;
        }
        else if (Input.GetAxis("Mouse ScrollWheel") != 0)
        {
            if (Input.GetAxis("Mouse ScrollWheel") < 0)
            {
                if (Camera.main.fieldOfView <= 100)
                    Camera.main.fieldOfView += 2;
                if (Camera.main.orthographicSize <= 20)
                    Camera.main.orthographicSize += 0.5F;
            }
            if (Input.GetAxis("Mouse ScrollWheel") > 0)
            {
                if (Camera.main.fieldOfView > 2)
                    Camera.main.fieldOfView -= 2;
                if (Camera.main.orthographicSize >= 1)
                    Camera.main.orthographicSize -= 0.5F;
            }
        }
        else
        {
            isMouseDown = false;
        }
    }

    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);
    }
}