#!ruby -Ku
# -*- mode: ruby; coding: utf-8 -*-
# Last updated: <2017/04/15 10:58:24 +0900>
#
# Arrayのベンチマーク
#
# [y][x][r, g, b, a] の配列からDXRubyのImageに変換する処理をいくつか試す

require 'dxruby'
require 'benchmark'

# 元画像データの生成
def make_src_array(w, h)
  src = Array.new(h) { Array.new(w) }
  h.times do |y|
    w.times do |x|
      r = 255 * x / (w - 1)
      g = 255 * y / (h - 1)
      b = 255 * (w - 1 - x) / (w - 1)
      a = 255
      src[y][x] = [r, g, b, a]
    end
  end
  return src
end

# Imageに1ドットずつRGBを書き込んでいくやり方
def convert_to_image(ary)
  w, h = ary[0].size, ary.size
  img = Image.new(w, h, [0, 0, 0, 0])
  h.times do |y|
    w.times do |x|
      r, g, b, a = ary[y][x]
      img[x, y] = a, r, g, b
    end
  end
  return img
end

# Imageに1ドットずつRGBを書き込んでいくやり方その2
def convert_to_image2(ary)
  w, h = ary[0].size, ary.size
  img = Image.new(w, h, [0, 0, 0, 0])
  ary.each_with_index do |line, y|
    line.each_with_index do |rgba, x|
      # img[x, y] = rgba[3], rgba[0], rgba[1], rgba[2]
      r, g, b, a = rgba
      img[x, y] = a, r, g, b
    end
  end
  return img
end

# 配列を平坦化してRGBAをARGBに並び替え、Image.createFromArrayを使う
def convert_to_image3(ary)
  w, h = ary[0].size, ary.size
  d = ary.flatten
  i = 0
  while i < d.size
    # d[i], d[i+1], d[i+2], d[i+3] = d[i+3], d[i], d[i+1], d[i+2]
    # d[i, 4] = d.values_at(i + 3, i, i + 1, i + 2)
    d[i, 4] = d[i+3], d[i], d[i+1], d[i+2]
    i += 4
  end
  return Image.createFromArray(w, h, d)
end

# ループを回してARGB並びの配列を作成後、Image.createFromArrayを使う
def convert_to_image4(ary)
  w, h = ary[0].size, ary.size
  d = []
  ary.each do |line|
    line.each do |r, g, b, a|
      # d.push(a) ; d.push(r) ; d.push(g) ; d.push(b)
      d << a << r << g << b
    end
  end
  return Image.createFromArray(w, h, d)
end

# ----------------------------------------

src = make_src_array(1600, 140)  # 元画像データ作成
imgs = []

# 配列をDXRubyのImageに変換
Benchmark.bm(12) do |x|
  x.report("Image[]  ") { imgs.push(convert_to_image(src)) }
  x.report("Image[]2 ") { imgs.push(convert_to_image2(src)) }
  x.report("flatten  ") { imgs.push(convert_to_image3(src)) }
  x.report("loop     ") { imgs.push(convert_to_image4(src)) }
end

Window.resize(800, 600)
Window.loop do
  break if Input.keyPush?(K_ESCAPE)

  x, y = 0, 0
  imgs.each do |img|
    Window.draw(x, y, img)
    y += img.height + 4
  end
end