ft: improved npc spawning logic

evolve-die-repeat/shared/npc/spawn_manager_2d.gd

@@ -0,0 +1,41 @@
+extends Node
+class_name SpawnManager2D
+
+#var scene = preload("res://molecular/nucleotide_prey.tscn")
+@export var scene: PackedScene
+@export var minCount = 1
+@export var maxCount = 2
+@export var spawnRange: Rect2
+var _currentCount = 0
+
+
+# Called when the node enters the scene tree for the first time.
+func _ready() -> void:
+	_spawn_minimum()
+
+# Called every frame. 'delta' is the elapsed time since the previous frame.
+func _process(delta: float) -> void:
+	pass
+
+func _spawn_minimum() -> void:
+	while _currentCount < minCount and _currentCount < maxCount:
+		_spawn_random()
+
+func _random_pos() -> Vector2:
+	return Vector2(randf_range(spawnRange.position[0], spawnRange.size[0]), randf_range(spawnRange.position[1], spawnRange.size[1]))
+
+func _spawn_random() -> void:
+	var pos = _random_pos()
+	_spawn_creature(pos)
+	_currentCount += 1
+
+func _spawn_creature(position: Vector2) -> void:
+	var instance = scene.instantiate()
+	instance.position = position
+	add_child(instance)
+	if instance.has_signal("died"):
+		instance.died.connect(_on_entity_died)
+		
+func _on_entity_died() -> void:
+	_currentCount = max(0, _currentCount-1)
+	_spawn_minimum()