Как в данном коде сделать так что ьы персонаж не прыгал по воздуху а по земле

 using UnityEngine;  
  
public class Controller : MonoBehaviour  
{  
    public float speed = 10f;  
    public float jumpForce = 10f;  
    public Rigidbody rb; // Reference to the Rigidbody component  
    public LayerMask groundLayer; // Specify the Ground layer  
    private bool isGrounded;  
  
    void Start()  
    {  
        rb = GetComponent(); // Assign the Rigidbody component  
    }  
  
    void Update()  
    {  
        // Check if the character is grounded  
        isGrounded = IsGrounded();  
  
        // Move the character forward  
        float vertical = 1f; // Set a constant forward movement  
        Vector3 move = transform.forward * vertical * speed;  
  
        // Apply movement  
        rb.MovePosition(rb.position + move * Time.deltaTime);  
  
        // Jump only when the Jump button is pressed and the character is grounded  
        if (Input.GetButtonDown("Jump") && isGrounded)  
        {  
            Jump(); // Call the Jump method  
        }  
    }  
  
    // Make the Jump method public so it can be accessed from the Unity Editor  
    public void Jump()  
    {  
        rb.velocity = new Vector3(rb.velocity.x, jumpForce, rb.velocity.z);  
    }  
  
    bool IsGrounded()  
    {  
        // Check if the character is close to the ground using the collider  
        float raycastDistance = 0.2f;  
        RaycastHit hit;  
  
        if (Physics.Raycast(transform.position, Vector3.down, out hit, raycastDistance, groundLayer))  
        {  
            return true;  
        }  
  
        return false;  
    }  
}