qr.cr

qr.cr

require "qrencode"
require "stumpy_png"
include StumpyPNG

qr = QRencode::QRcode.new("this is my input string")

margin = 20

size_with_margin = 300
size = size_with_margin - (margin * 2)

scale = size / qr.width
leftover = size - (scale * qr.width)
add_to_each_nth = qr.width / leftover

puts "Size: #{size} Scale: #{scale} Final width: #{size_with_margin}"

canvas = Canvas.new(size_with_margin, size_with_margin) do |x, y|
  if margin <= x < (size + margin) && margin <= y < (size + margin)
    x -= margin
    y -= margin

    block_x = x // scale
    block_y = y // scale

    used_leftovers_x = [block_x / add_to_each_nth, leftover].min
    used_leftovers_y = [block_y / add_to_each_nth, leftover].min

    x -= used_leftovers_x
    y -= used_leftovers_y
    x = x // scale
    y = y // scale

    if QRencode::Util.black?(qr.data[x + qr.width * y])
      RGBA::BLACK
    else
      RGBA::WHITE
    end
  else
    RGBA::BLUE
  end
end

StumpyPNG.write(canvas, "test.png")