struggling to get collision detection to work with rigidbodies

[winged trout]

heya, i cant figure out why my collision detection isn't working. im trying to make two objects merge into a new node like in suika game or 2048. I've followed a couple tutorials as well as tried using chatGPT to explain what i could be doing wrong but i cant figure it out. i have a rigid body parent node with a sprite and a collisionpolygon2d, i have connected the body entered signal and tried printing text to test the collision.

extends RigidBody2D

@export var node_value: int = 1
signal merged(new_node)

func _ready():
body_entered.connect(_on_body_entered)

func _on_body_entered3(body):
print("Body entered:", body)

func merge_with(other):
# Create a new node with the combined value
var new_node = preload("res://scenes/chipruby.tscn").instantiate()
new_node.node_value = node_value + 1
new_node.position = position.lerp(other.position, 0.5) # Place between the two nodes
emit_signal("merged", new_node)

func _on_body_entered(other):
if other is RigidBody2D and other.node_value == node_value:
merge_with(other)

# Free the old nodes
other.queue_free()
queue_free()

[fickle carbon]

Have to enable Contact Monitor in the body properties

[winged trout]

tried this and it still doesnt seem to be working.

[orchid thorn]

func _on_body_entered3(body):
print("Body entered:", body)
Is this a syntax error with the _on_body_entered3

[winged trout]

sorry are you asking if it is?

[orchid thorn]

Yeah

[winged trout]

oh i dont know honestly

[orchid thorn]

It might be

Try deleting the 3 from that and try it again

[winged trout]

still not seeing any print

[orchid thorn]

Hmm

Have you considered using the area 2d as opposed to rigid body 2d?

[winged trout]

yes but then how would i add physics to the nodes? it would be integral to the game im trying to make

[mystic slate]

strings are concatenated with +
And i do not think it would convert body to a String automatically either.
But maybe there is a syntax i don't know about

[winged trout]

so how should i change the code to update it to that syntax?

[mystic slate]

Replace the , with an +
And use a string instead of just body
I think str(body) works.

[fickle carbon]

(Print automatically converts all args to string and concats them. print("hello",123) outputs "hello123")

[mystic slate]

did not knew that, thanks again :)

[cunning canyon]

You are not going to get body_entered signal to fire for your RigidBody2D nodes because they are not going to enter eachother.

The physics engine will prevent two RigidBody2D nodes from overlapping.

See this similar question on the forums https://forum.godotengine.org/t/misunderstanding-about-physics-and-on-body-entered/38360

As yesfish said above, you can override this and have RigidBody2Ds report on contact by enabling the contact_monitor property of the RigidBody2D as well as specifying a non-zero max_contacts_reported