instancing a scene

takedabro1

hello, im trying to instance a scene in an endless runner im making, the idea is that once the platform is at a certain point, it will delete itself and instance a new one a bit ahead, how far away it is is determined by a collision polygon. for some reason, it is not instancing the scene even though everything else is working, what am i doing wrong? here is my code for the spawner:

	extends Spatial
	
	onready var tileScene = load("res://scenes/tile.tscn")
	
	func _on_CollisionPolygon_tree_entered():
		print("spawining")
		tileScene.translation.z = 5;
		var tile = tileScene.instance()
		add_child(tile)

thanks in advance! (asking again because i didnt get an answer the first time)

TwistedTwigleg

Are you sure the _on_CollisionPolygon_tree_entered function is being called?

Also, two other things that could be causing the issue is that the new tile is spawned at the same position as the current tile (you are not changing its position) and because it is a child of the current tile, it will be deleted when the current tile is deleted (child nodes are deleted when the parent is deleted). Maybe try this:

extends Spatial
onready var tileScene = load("res://scenes/tile.tscn")

func _on_CollisionPolygon_tree_entered():
	print ("Spawning")
	tileScene.translation.z = 5;
	var tile = tileScene.instance()
	# position the tile
	var tile_offset = Vector3(0, 0, 5)
	tile.global_transform.origin = global_transform.origin + tile_offset
	# instead of adding the tile as a child of this node
	# add it as a child to this node's parent!
	get_parent().add_child(tile)

takedabro1

@TwistedTwigleg i've made sure the collision is working using the print() function. when i try to run that code the error message i get is: Invalid call. Nonexistent function 'instance' in base 'Nil'. (line 7), i tried using: ` onready var tileScene = preload("res://scenes/tile.tscn")

func _input(event: InputEvent) -> void:
	if event is InputEvent:
		if event.is_action_pressed("ui_select"):
			print ("Spawning")
			spawn()

func spawn():
	var t = tileScene.instance()
	add_child(t)`

and that worked, but when i try

` onready var tileScene = preload("res://scenes/tile.tscn")

func _on_CollisionPolygon_tree_entered():
	print ("Spawning")
	spawn()

func spawn():
	var t = tileScene.instance()
	add_child(t)`

that gave me the same error message

TTaykAH

Maybe _on_CollisionPolygon_tree_entered() method calls before _ready() , so tileScene variable hasn't received value yet and you call instance() method. Try to put print("something") into _ready() method and see if it's in the console something. If my assumption is correct, try to change tree_entered() signal to ready()(as far as I understand this method connected to signal).

TwistedTwigleg

Something else you can try is using a constant and a preload instead of an onready load:

extends Spatial

# Now a constant with a preload
const TILE_SCENE = preload("res://scenes/tile.tscn")

func _on_CollisionPolygon_tree_entered():
	print ("Spawning")
	# changed this to self! This may have also been contributing to the error
	self.translation.z = 5;
	var tile = TILE_SCENE.instance()
	var tile_offset = Vector3(0, 0, 5)
	tile.global_transform.origin = global_transform.origin + tile_offset
	get_parent().add_child(tile)

takedabro1

thanks both of you but i actually manage to fix it and didnt bother to look at the forum (oops) the fix was that i shouldnt have used func _on_CollisionPolygon_tree_entered(): i shouldve used func _on_Area_body_entered(body):

thanks anyways!