Layers and Masks

Part of the Signals and Collisions section of Coddy's Godot journey. Lesson 22 of 27.

Bodies and areas sit on numbered collision layers. Each has two settings:

collision_layer: the layers it is on.
collision_mask: the layers it looks at. An area notices only bodies on a layer in its mask.

Both are numbers. Layer 1 is 1, layer 2 is 2, layer 3 is 4, layer 4 is 8. Everything starts on layer 1 with mask 1, so everything notices everything.

Here the player is on layer 2 and the coral ball is on layer 1. To let only the player take the coin, the coin looks at layer 2 alone:

func _ready():
	collision_mask = 2

Challenge

Medium

Let the coin notice only the player.

The player is on layer 2. At the start of _ready(), set the coin's collision_mask so it notices only layer 2.
Leave the connect line as it is.

Press Play: the ball rolls through the coin, then you walk up and take it. Then Check.

Try it yourself

extends Area2D

func _ready():
	body_entered.connect(_on_body_entered)

func _on_body_entered(body):
	queue_free()

Test yourself

This lesson includes a short quiz. Start the lesson to answer it and track your progress.

All lessons in Signals and Collisions

Practice on your own: Godot playground