Script for camera movement using Arcball,Scripting Camera Movements with Arcball

I wrote the following script, but I have a problem that the camera moves upward the moment I drag the mouse. How can I make it so that the camera does not move instantly when I drag the mouse?

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

[RequireComponent(typeof(Camera))] public class ArcballScript : MonoBehaviour { // Is true when the user wants to rotate the camera bool ballEnabled = false;

 float rotationSpeed = 1f;
 float radius = 5f;

 // The mouse cursor's position during the last frame
 Vector3 last = new Vector3();

 // The target that the camera looks at
 Vector3 target = new Vector3(0, 0, 0);

 // The spherical coordinates
 Vector3 sc = new Vector3();

 void Start()
 {
     this.transform.position = new Vector3(radius, 0.0f, 0.0f);
     this.transform.LookAt(target);
     sc = getSphericalCoordinates(this.transform.position);
 }

 Vector3 getSphericalCoordinates(Vector3 cartesian)
 {
     float r = Mathf.Sqrt(
         Mathf.Pow(cartesian.x, 2) +
         Mathf.Pow(cartesian.y, 2) +
         Mathf.Pow(cartesian.z, 2)
     );

     float phi = Mathf.Atan2(cartesian.z / cartesian.x, cartesian.x);
     float theta = Mathf.Acos(cartesian.y / r);

     if (cartesian.x < 0)
         phi += Mathf.PI;

     return new Vector3(r, phi, theta);
 }

 Vector3 getCartesianCoordinates(Vector3 spherical)
 {
     Vector3 ret = new Vector3();

     ret.x = spherical.x * Mathf.Cos(spherical.z) * Mathf.Cos(spherical.y);
     ret.y = spherical.x * Mathf.Sin(spherical.z);
     ret.z = spherical.x * Mathf.Cos(spherical.z) * Mathf.Sin(spherical.y);

     return ret;
 }

 // Update is called once per frame
 void Update()
 {
     // Whenever the left mouse button is pressed, the
     // mouse cursor's position is stored for the arc-
     // ball camera as a reference.
     if (Input.GetMouseButtonDown(0))
     {
         // last is a global vec3 variable
         last = Input.mousePosition;

         // This is another global variable
         ballEnabled = true;
     }

     // When the user releases the left mouse button,
     // all we have to do is to reset the flag.
     if (Input.GetMouseButtonUp(0))
         ballEnabled = false;

     if (ballEnabled)
     {
         // Get the deltas that describe how much the mouse cursor got moved between frames
         float dx = (last.x - Input.mousePosition.x) * rotationSpeed;
         float dy = (last.y - Input.mousePosition.y) * rotationSpeed;

         // Only update the camera's position if the mouse got moved in either direction
         if (dx != 0f || dy != 0f)
         {
             // Rotate the camera left and right
             sc.y += dx * Time.deltaTime;

             // Rotate the camera up and down
             // Prevent the camera from turning upside down (1.5f = approx. Pi / 2)
             sc.z = Mathf.Clamp(sc.z + dy * Time.deltaTime, -1.5f, 1.5f);

             // Calculate the cartesian coordinates for unity
             transform.position = getCartesianCoordinates(sc) + target;

             // Make the camera look at the target
             transform.LookAt(target);
         }

         // Update the last mouse position
         last = Input.mousePosition;
     }
 }

}, I wrote the following script, but I have a problem that the camera moves upward the moment I drag the mouse. How can I make it so that the camera does not move instantly when I drag the mouse?

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

[RequireComponent (typeof (Camera))] public class ArcballScript : MonoBehaviour { // Is true when the user wants to rotate the camera bool ballEnabled = false;

 float rotationSpeed = 1f;
 float radius = 5f;
 
 // The mouse cursor's position during the last frame
 Vector3 last = new Vector3();
 
 // The target that the camera looks at
 Vector3 target = new Vector3 (0, 0, 0);
 
 // The spherical coordinates
 Vector3 sc = new Vector3 ();
 
 void Start ()
 {
     this.transform.position = new Vector3 (radius, 0.0f, 0.0f);
     this.transform.LookAt (target);
     sc = getSphericalCoordinates (this.transform.position);
 }
 
 Vector3 getSphericalCoordinates(Vector3 cartesian)
 {
     float r = Mathf.Sqrt(
         Mathf.Pow(cartesian.x, 2) + 
         Mathf.Pow(cartesian.y, 2) + 
         Mathf.Pow(cartesian.z, 2)
     );
 
     float phi = Mathf.Atan2(cartesian.z / cartesian.x, cartesian.x);
     float theta = Mathf.Acos(cartesian.y / r);
 
     if (cartesian.x < 0)
         phi += Mathf.PI;
 
     return new Vector3 (r, phi, theta);
 }
 
 Vector3 getCartesianCoordinates(Vector3 spherical)
 {
     Vector3 ret = new Vector3 ();
 
     ret.x = spherical.x * Mathf.Cos (spherical.z) * Mathf.Cos (spherical.y);
     ret.y = spherical.x * Mathf.Sin (spherical.z);
     ret.z = spherical.x * Mathf.Cos (spherical.z) * Mathf.Sin (spherical.y);
 
     return ret;
 }
  
 // Update is called once per frame
 void Update ()
 {
     // Whenever the left mouse button is pressed, the
     // mouse cursor's position is stored for the arc-
     // ball camera as a reference.
     if (Input.GetMouseButtonDown(0))
     {
         // last is a global vec3 variable
         last = Input.mousePosition;
 
         // This is another global variable
         ballEnabled = true;
     }
 
     // When the user releases the left mouse button,
     // all we have to do is to reset the flag.
     if (Input.GetMouseButtonUp (0))
         ballEnabled = false;
 
     if (ballEnabled)
     {
         // Get the deltas that describe how much the mouse cursor got moved between frames
         float dx = (last.x - Input.mousePosition.x) * rotationSpeed;
         float dy = (last.y - Input.mousePosition.y) * rotationSpeed;
 
         // Only update the camera's position if the mouse got moved in either direction
         if (dx != 0f || dy != 0f)
         {
             // Rotate the camera left and right
             sc.y += dx * Time.deltaTime;
 
             // Rotate the camera up and down
             // Prevent the camera from turning upside down (1.5f = approx. Pi / 2)
             sc.z = Mathf.Clamp (sc.z + dy * Time.deltaTime, -1.5f, 1.5f);
 
             // Calculate the cartesian coordinates for unity
             transform.position = getCartesianCoordinates (sc) + target;
 
             // Make the camera look at the target
             transform.LookAt (target);
         }
 
         // Update the last mouse position
         last = Input.mousePosition;
     }
 }

}