(2D) How to check if surface does not contain Area2D?

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:bust_in_silhouette: Asked By Vododovoodvod

I would like to procedurally spawn objects which are basically Area2D nodes with circular collision shapes. This Areas should not overlap.

I am not cure how to do check if certain circular surface of the scene is free of existing collision shapes.

:bust_in_silhouette: Reply From: timothybrentwood

Using math :wink:
Assuming your Area2D is it’s own scene with CollisionShape2D as its child:

var area_2d_scene = preload("res://default_env.tres")
func spawn_units():
	var objects_spawned = []
	var num_to_spawn = 10
	while objects_spawned.size() < num_to_spawn:
		var potential_spawn_location = get_random_vector_within_bounds()
		var can_place = true
		for object in objects_spawned:
			var object_radius_squared = pow(2 * object.get_node("CollisionShape2D").shape.radius, 2)
			if potential_spawn_location.distance_squared_to(object.position) < object_radius_squared:
				can_place = false
		if can_place:
			var new_object = area_2d_scene.instance()
			new_object.position = potential_spawn_location

Few things to note: using a while loop is generally inadvisable here. You would need to implement get_random_vector_within_bounds(). This assumes all objects have the same radii.

Thank you for your help!

Vododovoodvod | 2021-05-03 18:27