### A snipped from the Rock Scene
func spawn(_pos, _vel, _size):
    position = _pos
    size = _size
    mass = 1.5 * size
    $Explosion.scale = Vector2(0.75, 0.75) * size
    $Sprite.scale = Vector2(1, 1) * scale_factor * _size
    radius = int($Sprite.texture.get_size().x / 2 * scale_factor * _size)
    var shape = CircleShape2D.new()
    shape.radius = radius
    $CollisionShape2D.shape = shape
    linear_velocity = _vel
    angular_velocity = rand_range(-1.5, 1.5)

### A snipped from main
func _ready():
    randomize()
    screensize = get_viewport().get_visible_rect().size
    $Player.screensize = screensize
    for i in range(3):
        spawn_rock(3)


func spawn_rock(_size, _pos=null, _vel=null):
    if !_pos:
        $RockPath/RockSpawn.set_offset(randi())
        _pos = $RockPath/RockSpawn.position
    if !_vel:
        _vel = Vector2(1, 0).rotated(rand_range(0, 2*PI)) * rand_range(100, 150)
    var r = rock.instance()
    r.screensize = screensize
    r.spawn(_pos, _vel, _size)
    r.connect("exploded", self, "_on_Rock_exploded")
    $Rocks.add_child(r)


func _on_Rock_exploded(_size, _radius, _pos, _vel):
    if _size <= 1:
        return
    for offset in [-1, 1]:
        var _dir = (_pos - $Player.position).normalized().tangent() * offset
        var newpos = _pos + _dir * _radius
        var newvel = _dir * _vel.length() * 1.1
        spawn_rock(_size - 1, newpos, newvel)