Godot L-System Koch Snowflake

canvas.gd

extends Node2D

var axiom = "F++F++F++"
var angle_step = deg_to_rad(60)
var iteration = 1
var step_length: float = 64

var rules = {
	"F": "F-F++F-F"
}

# Called when the node enters the scene tree for the first time.
func _ready():
	pass # Replace with function body.

# Called every frame. 'delta' is the elapsed time since the previous frame.
func _process(delta):
	pass

func _draw():
	var start_x = get_window().size.x / 2
	var position = Vector2(start_x, get_window().size.y)
	var angle = angle_step
	var current = LNode.new(angle, position, step_length)
	var stack = []
	
	for command in axiom:
		match(command):
			"F":
				var delta = Vector2.UP.rotated(current.angle) * current.step_length
				var end_point = current.position + delta
				draw_line(current.position, end_point, Color.GREEN, 1.0)
				current.position = end_point
			"+":
				current.angle -= angle_step
			"-":
				current.angle += angle_step


func _on_button_pressed():
	iteration += 1
	var new_axiom = ""
	for command in axiom:
		var rule = rules.get(command, command)
		new_axiom += rule
	
	axiom = new_axiom
	queue_redraw()

func _on_shrink_pressed():
	step_length /= 2
	step_length = max(0.1, step_length)
	queue_redraw()