2D Map editor

Unity Engine
1

Hello!

I made a custom editor to draw my levels for a game I am working on,
But I want to check if there is not already a tile where I want to click

    private void OnSceneGUI()
    {
        HandleUtility.AddDefaultControl(GUIUtility.GetControlID(FocusType.Passive));
        _mousepos = Event.current.mousePosition;


        if (Event.current.type == EventType.MouseDown && Event.current.button == 0)
        {
            _tileParent = GameObject.Find("Level");


            Ray ray = HandleUtility.GUIPointToWorldRay(_mousepos);


            Debug.DrawRay(ray.origin, Vector3.forward* 100, Color.white, 4);
            if (Physics.Raycast(ray.origin, new Vector3(0, 0, 100f), 1000f))
            {
                //doesnt work
                if (_tileParent != null)
                {
                    if (_currentTile != null)
                    {

                        int x = (int)Mathf.Round(ray.origin.x);
                        int y = (int)Mathf.Round(ray.origin.y);
                        GameObject clone = Instantiate(_currentTile, new Vector2(x, y), _currentTile.transform.rotation) as GameObject;

                        if (clone != null)
                        {
                            clone.transform.SetParent(_tileParent.transform);
                        }
                    }
                }
            }

        }
  
    }

I searched every where but it doesnt seem to work
can someone help me out please

2

Forgot to change that in the code

if (!Physics.Raycast(ray.origin, new Vector3(0, 0, 100f), 1000f))

But it won’t work either