Help with conecting signal at runtime to 3 other scenes

Help
,
1

Godot Version

4.7 stable

Problem

The problem is that I can’t send a signal from my bullet to my player because the bullet is not instantiated yet.

However, I need to know when the bullet hits something, so I added an Area2D to the bullet and connected its signal to the bullet script.

Now I want the bullet scene to send a signal, which is received by three other scripts.

Is there a way to create or connect a signal at runtime when the bullet is spawned?

I’ve read the documentation about signals, but I couldn’t find anything that addresses this problem. I also searched around on DuckDuckGo, but the only solutions I found were very complex and relied on global scripts.

Is it posible to send a signal to 3 other nodes?

2

Yes. And you can await the bullet entering the scene succesfully as well using it’s ready signal, though I don’t think you need that.

In my pseudo code (typing on phone r.n.):


func spawn_bullet() -> void:
    var bullet = YourPreloadedBulletSceneName.instantiate()
    some_node.add_child(bullet)
    # await bullet.ready 
    # don't think you need to await to connect the signal
    bullet.your_hit_signal.connect(self.some_method)
    bullet.your_hit_signal.connect(some_other_node.method)

Oh and you need to declare your_hit_signal too in the bullet script and call your_hit_signal.emit() from the method that receives a signal from its Area2D

3

okay thank you i wil try this now (i may need more help bc i am a bit confused) and see.

Wow godot comunety is soo nice, ik how hard it is to type script on phone :blush:
i rally apriciate this. : )

4

Okay i have tried to conect it to my player but it dose not work, (bc i made a mistake)
and i get this error: Error at (9, 29): Cannot find member “bat_died” in base “Node2D”.
Her is my player code:

extends Node2D


@export var bat_scene: PackedScene
@onready var cpu_particles_2d: CPUParticles2D = $CPUParticles2D

var shooting = true


func _on_button_button_down() -> void:
	if shooting == true:
		cpu_particles_2d.emitting = true
		var bullet = bat_scene.instantiate()
		bullet.global_position = global_position
		get_tree().current_scene.add_child(bullet)
		shooting = false


func bat_died() -> void:
	shooting = true

and her my bullet/bat:

extends RigidBody2D


signal bat_died
var shoot_power: int = 330

func _ready() -> void:
	apply_central_impulse(Vector2(0.9, 0.1) * shoot_power)
	bat_died.connect(Node2D.bat_died)

func _on_hurt_area_2d_area_shape_entered(_area_rid: RID, _area: Area2D, _area_shape_index: int, _local_shape_index: int) -> void:

	bat_died.emit()
5

You should connect to bat_died in your first script.

What you’re doing in the second script’s _ready will not work, because Node2D is a class name, and not an actual instance of a Node2D.

So what may work is to add this to your _on_button_button_down function:

         bullet.bat_died.connect(self.bat_died)

But also remove the line saying the invalid Node2D.connect(..)

6

Thank you very much it works now, and i finaly understand custom signals. :blush:
Now i wil just conect it to my UI controler. :slight_smile: