How to prevent a character from being able to jump mid air ?

Questions & Answers
1

I am new to unity and was trying to put in raycasting to see if the player is grounded. However, it seems to do nothing as my character can still jump in the air. What am I doing wrong?

using UnityEngine;

public class Player2dController : MonoBehaviour
{

    private Rigidbody2D body;
    private BoxCollider2D boxCollider;

    [SerializeField] private float speed;
    [SerializeField] private float jump;
    [SerializeField] private LayerMask groundLayer;


    private void Awake()
    {
        //References
        body = GetComponent<Rigidbody2D>();
        boxCollider = GetComponent<BoxCollider2D>();
    }

    private void Update()
    {
        float horizontalInput = Input.GetAxis("Horizontal");
        body.velocity = new Vector2(horizontalInput * speed, body.velocity.y);

        //flip player in moving direction
        if (horizontalInput > 0.01f)
            transform.localScale = Vector3.one;
        else if (horizontalInput < -0.01f)
            transform.localScale = new Vector3(-1, 1, 1);


        if (Input.GetKey(KeyCode.Space) && isGrounded())
            Jump();
            
    }

    private void Jump()
    {
        body.velocity = new Vector2(body.velocity.x, jump);
    }

    private bool isGrounded()
    {
        RaycastHit2D raycastHit = Physics2D.BoxCast(boxCollider.bounds.center, boxCollider.bounds.size, 0, Vector2.down, 0.1f, groundLayer);
        return raycastHit.collider != null;
    }
}
2

Hey there,

if you have issues with raycasts i can only suggest to always

  1. put up a Debug.Log to see what object you actually hit
  2. add a Debug.Line to see from where to where your ray actually goes.

Following these 2 points will most likely solve your issue as your ray probably just hits your player and will thus always return true for isGrounded().

This might also reveal for example that your groundLayer layermask is not set up correctly.

Let me know if that helped. If not please share the results of these two points with us.