Godot Map/Lerp a Range of numbers

extends Node2D

onready var label = $Label
onready var color_1 = $ColorRect
onready var color_2 = $ColorRect2

func _ready():
    pass # Replace with function body.

func _process(delta):
    var x = get_global_mouse_position().x
    var y = get_global_mouse_position().y
    var w = get_viewport().size.x
    var h = get_viewport().size.y

    var v1 = range_lerp(x,0,w,0,255)
    var v2 = range_lerp(x,0,w,255,0)
    var v3 = range_lerp(y,0,h,255,0)

    label.text = "v1: " + String(v1) + "\nv2: " + String(v2)
    label.text += "\nv3: " + String(v3)

    color_1.color = Color8(v3,v3,v1)
    color_2.color = Color8(v2,v3,v3)