unityでJoyStickでもボール操作できるようにしたい

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

public class GamenDrag : MonoBehaviour
{

private Rigidbody rb;
private const float MaxMagnitude = 2f;
private Vector3 force;
private Camera mainCamera;
private Vector3 dragPos = Vector3.zero;
private static float speed;
public GameObject Background;



[SerializeField]
private LineRenderer direction = null;


public AudioClip SeJump;
AudioSource audioSource;





public void Start()
{

   
    rb = this.GetComponent<Rigidbody>();
    mainCamera = Camera.main;

    audioSource = GetComponent<AudioSource>();


}





public void OnMouseDown()
{
    var position = Input.mousePosition;
    position.z = mainCamera.transform.position.z;
    position = mainCamera.ScreenToWorldPoint(position);
    position.y = 0;
    dragPos = position;


    this.direction.enabled = true;
    this.direction.SetPosition(0, this.rb.position);
    this.direction.SetPosition(1, this.rb.position);


}

public void OnMouseDrag()
{
     
    var position = Input.mousePosition;
    position.z = mainCamera.transform.position.z;
    position = mainCamera.ScreenToWorldPoint(position);
    position.y = 0;
    force = position - dragPos;

    this.direction.enabled = true;
    this.direction.SetPosition(0, this.rb.position);
    this.direction.SetPosition(1, this.rb.position + force);
}



public void OnMouseUp()
{
    audioSource.PlayOneShot(SeJump);
    speed = 4.3f;
    rb.AddForce(force * speed, ForceMode.Impulse);


}