Null instance error when setting global player position from save screen

Help
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1

Godot Version

4.6.1 Stable

Question

Hi everyone. So I’m working on a practice JRPG prototype and one of the things I wanted to do is create a ‘save room’ that the player saves in and then leaves.

What I have set up right now is a debug room which contains the Player node as a unique name, with the following script.

class_name Player extends CharacterBody3D

#region Variables
@onready var forward: RayCast3D = $Forward
@onready var right: RayCast3D = $Right
@onready var left: RayCast3D = $Left
const SPEED: float = 0.3
const ROTATE_SPEED: float = 0.4 
@onready var tween: Tween
#endregion

I then instantiated a separate control node scene, which is my save UI menu. Its just two buttons, right now, one for saving and exiting, with the following script:

extends Control

@onready var player: Player = %Player
@onready var save: Button = $Options/Save
@onready var exit: Button = $Options/Exit
@onready var spawn_point: Marker3D = %SpawnPoint


const SAVE_PATH = "user://savegame.data"
@warning_ignore("untyped_declaration")

func _ready() -> void:
	player = get_tree().get_first_node_in_group("Player")

func _on_options_button_pressed(button: BaseButton, index: int) -> void:
	match button.text:
		"SAVE":
			@warning_ignore("untyped_declaration")
			var file =  FileAccess.open(SAVE_PATH, FileAccess.WRITE)
			@warning_ignore("untyped_declaration")
			var saved_data = {}
		  
			saved_data["player_global_position"] = player.global_position

			file.store_var(saved_data)
			file.close()
		
		"EXIT":
			TransitionLayer.change_level("res://src/dungeons/debug_room/debug_room.tscn")
			player.global_position = spawn_point.global_position
		_:
			pass

I want to have it so that the player’s position on pressing the ‘exit’ button places them at a Marker3D location. Of course the issue is, since these are two separate scenes, I receive the following error:

“Invalid access to property or key ‘global_position’ on a base object of type ‘null instance’.”

I assume the issue is, the ‘player’ is a null instance since it doesn’t exist in the save screen. So my question is, what should I be doing instead to make this work? Simply copying in the Player node into the save screen does not work.

Thank you.

2

Are you sure the problem is the player variable and not spawn_point?

Unique node names can only be used within the same scene. If your control node is part of a different scene, you can’t access the player nor the spawn point this way. For player this shouldn’t matter (because you are setting it to get_tree().get_first_node_in_group("Player") in _ready()), but spawn_point would still be null.

The easiest way to access these nodes is probably to @export both variables:

@export var player: Player
@export var spawn_point: Marker3D

and set them in the Inspector in the debug room scene.