Splatoon2 picture drawing application (requires raspberrypi + UFB)

ikadraw.rb

# coding: utf-8

require 'rmagick'
require 'optparse'
require 'pi_piper'
include PiPiper

class Gpio
  DELAY = 0.04

  DOT_PIN   = 12
  RIGHT_PIN = 16
  LEFT_PIN  = 20
  DOWN_PIN  = 21

  def initialize
    @dot = Pin.new pin: DOT_PIN, direction: :out
    @dot.on

    @right = Pin.new pin: RIGHT_PIN, direction: :out
    @right.on

    @left = Pin.new pin: LEFT_PIN, direction: :out
    @left.on

    @down = Pin.new pin: DOWN_PIN, direction: :out
    @down.on
  end

  def DOT
    @dot.off
    sleep DELAY
    @dot.on
    sleep DELAY
  end

  def RIGHT
    @right.off
    sleep DELAY
    @right.on
    sleep DELAY
  end

  def LEFT
    @left.off
    sleep DELAY
    @left.on
    sleep DELAY
  end

  def DOWN
    @down.off
    sleep DELAY
    @down.on
    sleep DELAY
  end
end

# parsing options
params = ARGV.getopts('f:')

unless params['f']
  puts '-f required.'
  exit 1
end
filename = params['f']

unless FileTest.readable?(filename)
  puts "Error reading file #{filename}"
  exit 1
end

gpio = Gpio.new

include Magick
img = Magick::ImageList.new(filename)

(0..img.rows - 1).each do |row|
  # 偶数行なら正順で。カーソルも正順で
  if row.even?
    (0..img.columns - 1).each do |col|
      gpio.DOT if img.pixel_color(col, row).red.zero?
      gpio.RIGHT if col != img.columns - 1
    end
  else # 奇数行なら逆順で。カーソルも逆順で
    (0..img.columns - 1).reverse_each do |col|
      gpio.DOT if img.pixel_color(col, row).red.zero?
      gpio.LEFT if col != 0
    end
  end
  gpio.DOWN
end