@tool
extends Path3D
class_name RoadPath
@export_tool_button("update_control_points") var action = update_control_points

func modulo_get_point_position(i):
	return curve.get_point_position(posmod(i, curve.point_count))

func update_control_points():
	if curve.point_count < 2:
		return
	
	#
	## Start point: out control based on next point
	#var dir = (curve.get_point_position(1) - curve.get_point_position(0)).normalized()
	#var tangent_length = dir.length() / 3 
	#
	#curve.set_point_out(0, dir * tangent_length)
	
	# Intermediate points: in and out controls based on adjacent points
	for i in range(0, curve.point_count):
		var prev = modulo_get_point_position(i) - modulo_get_point_position(i - 1)
		var next = modulo_get_point_position(i + 1) - modulo_get_point_position(i)
		var prev_dir = prev.normalized()
		var next_dir = next.normalized()
		var tangent_length = next.length() / 3 
		var tangent = (prev_dir + next_dir)
		
		tangent.y = 0
		tangent = tangent.normalized()
		curve.set_point_in(i, -tangent * tangent_length)
		curve.set_point_out(i, tangent * tangent_length)