Why Isn't My 2D Collision Working

Unity Engine
, , ,
1

Please help me. I’ve been trying for a few hours but I can’t get this code to work:

void OnCollisionEnter2D(Collision2D col)
 {
     if (col.gameObject.name == "Collision Test")
     {
         Debug.Log("I hate coding");
     }
 }

It keeps saying “The local function ‘OnCollisionEnter2D’ is declared but never used” and I don’t know why. I have non-kinematic rigid bodies, I’m using MonoBehavior, I just don’t know what’s wrong.

1 Like
2

Check this: Local functions - C# | Microsoft Learn

Since you didn’t provide the full class, it’s worse for identifying the problem.

This function is located inside redundant curly brackets: { }

You have to get it out of here.

1 Like
3

Here’s the full script:

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

public class slappyMovement : MonoBehaviour
{
    // The stuff needed for movement :)
    public Rigidbody2D rigidBody;
    public float leftSpeed;
    public float rightSpeed;
    public float jumpHeight;
    public float flapHeight;
    private float flaps;
    public bool facingRight;
    
    // For handling deaths and stuff
    public float deathZone;
    private float lives;
    private bool parachute;

    // The stuff needed to check for ground, so you can jump :)
    public Transform groundCheck;
    public float groundCheckRadius;
    public LayerMask whatIsGround;
    private bool onGround;

    // I like smiley faces :)

    // Start is called before the first frame update :D
    void Start()
    {
        rigidBody = GetComponent<Rigidbody2D>();
        facingRight = true;
        lives = 3;
        parachute = false;
    }

    // Update is called once per frame :D
    void Update()
    {
        // Just ground stuff
        onGround = Physics2D.OverlapCircle(groundCheck.position, groundCheckRadius, whatIsGround);

        // For flipping the character left and right
        void Flip()
        {
            if (transform.localEulerAngles.y != 180 && facingRight == false)
                transform.Rotate(0f, 180f, 0f);
            else if (transform.localEulerAngles.y != 0 && facingRight == true)
                transform.Rotate(0f, -180f, 0f);
        }

        // Here is the problematic part
        void OnCollisionEnter2D(Collision2D col)
        {
            if (col.gameObject.name == "Ground")
            {
                Debug.Log("I hate coding");
            }
        }

        // For moving left
        if (Input.GetKey(KeyCode.A))
        {
            facingRight = false;
            Flip();
            rigidBody.velocity = new Vector2(leftSpeed, rigidBody.velocity.y);
        }

        // For moving right
        if (Input.GetKey(KeyCode.D))
        {
            facingRight = true;
            Flip();
            rigidBody.velocity = new Vector2(rightSpeed, rigidBody.velocity.y);
        }

        // For jumping
        if (Input.GetKeyDown(KeyCode.W) && onGround)
        {
            rigidBody.velocity = new Vector2(rigidBody.velocity.x, jumpHeight);
            flaps = 2;
        }

        // For flapping
        if (Input.GetKeyDown(KeyCode.W) && onGround == false && flaps > 0 && parachute == false)
        {
            rigidBody.velocity = new Vector2(rigidBody.velocity.x, jumpHeight);
            flaps -= 1;
        }

        // If the character falls off
        if (transform.position.y < deathZone)
        {
            Debug.Log("death");
            transform.position = new Vector2(-7, 5);
            parachute = true;
            lives -= 1;

            if (lives < 0)
            {
                Destroy(gameObject);
            }
        }

        // Code for the parachutes
        if (parachute == true)
        {
            rigidBody.drag = 10;
            if (onGround == true)
            {
                parachute = false;
            }
        }
        else
        {
            rigidBody.drag = 0;
        }

    



    }
}
1 Like
4

In your code, OnCollisionEnter2D() is located inside Update() — it’s wrong — that’s why it’s compiled as a local function.

2 Likes
5

Thanks a lot! Whenever I look at other forums, I wasn’t able to figure that out, so I really appreciate the help :slight_smile:

1 Like