在Unity中使用Touchscript移动的2D刚体不会停留在边界中

using UnityEngine;
using TouchScript.Gestures;

public class MoveWithTouch : MonoBehaviour
{
    private Rigidbody2D rigidbody;
    private Vector2 screenSize;

    private void Start()
    {
        rigidbody = GetComponent<Rigidbody2D>();
        screenSize = new Vector2(Camera.main.aspect * Camera.main.orthographicSize, Camera.main.orthographicSize);
    }

    private void Update()
    {
        Vector2 position = rigidbody.position;
        Vector2 newPosition = position;

        newPosition += GetTouchMovement() * Time.deltaTime;

        newPosition.x = Mathf.Clamp(newPosition.x, -screenSize.x, screenSize.x);
        newPosition.y = Mathf.Clamp(newPosition.y, -screenSize.y, screenSize.y);

        rigidbody.MovePosition(newPosition);
    }

    private Vector2 GetTouchMovement()
    {
        if (Input.touchCount > 0)
        {
            Touch touch = Input.GetTouch(0);
            return touch.deltaPosition;
        }
        else if (Input.GetMouseButton(0))
        {
            Vector2 mousePosition = new Vector2(Input.mousePosition.x, Input.mousePosition.y);
            return (mousePosition - rigidbody.position) * 10f; // Adjust the speed
        }

        return Vector2.zero;
    }
}