Help with OnCollisionEnter method.

Questions & Answers
1

Hello,

I am trying to have the color of a ball change when it hits a wall in my game. The if statement I have for this works but when I try to have it change to a different color after it hits the right wall again this is where I have run into issues. When the code runs right now, anytime the ball contacts another surface including the paddles it changes color. So how should I proceed forward? Should I move the color-changing part of the code to its own method or is there a way to help it run independently from the other collision parts of the code in the method?

void OnCollisionEnter2D(Collision2D collision)
    {
        if (collision.gameObject.name == "RacketLeft")
        {
            float y = hitFactor(transform.position, collision.transform.position, collision.collider.bounds.size.y);

            Vector2 dir = new Vector2(1, y).normalized;

            GetComponent<Rigidbody2D>().velocity = dir * speed;
        }

        if (collision.gameObject.name == "RacketRight")
        {
            float y = hitFactor(transform.position, collision.transform.position, collision.collider.bounds.size.y);

            Vector2 dir = new Vector2(1, y).normalized;

            GetComponent<Rigidbody2D>().velocity = dir * speed;
        }
        
        if (collision.gameObject.name == "Right Wall")
        {
            _renderer.sharedMaterial = materials[1];
        }
        else
        {
            _renderer.sharedMaterial = materials[0];
        }
    }
2

You can use layers for this…
like

if(collision.gameObject.layer == LayerMask.NameToLayer("wall"))
      { 
      }

just put this under the OnCollisionEnter2D method…and then appropriately tag all the walls…then you can use this if tag to trigger any event you want…you can make a similar if() and layer for the paddles

3

The problem is here:

if (collision.gameObject.name == "Right Wall") {
    _renderer.sharedMaterial = materials[1];
}
else {
    _renderer.sharedMaterial = materials[0];
}

using “else”, make change the color of the ball for every collision that not be “Right Wall”…

If I understand correctly your idea, you need to change the code like this:

if (collision.gameObject.name == "Right Wall") {
    _renderer.sharedMaterial = materials[1];
}
else if(collision.gameObject.name == "Left Wall"){
    _renderer.sharedMaterial = materials[0];
}