extends Sprite

export var scroll_speed = 9

var moving = false

signal viewport_entered(object)
signal viewport_exited(object)


func start():
	moving = true


func stop():
	moving = false


func _physics_process(delta):
	if moving:
		move()


func move():
	position.x -= scroll_speed


func _on_VisibilityNotifier2D_viewport_entered(viewport: Viewport) -> void:
	emit_signal("viewport_entered", self)


func _on_VisibilityNotifier2D_viewport_exited(viewport: Viewport) -> void:
	emit_signal("viewport_exited", self)