terminal colormap

colormap.rb

#!/usr/bin/env ruby

def color_map
  yield ->(offset) { ->(color) { print "\x1b[48;5;#{color + offset}m  " } }

  print "\x1b[0m", ?\n
end

puts 'System colors:'
color_map { |color| 8.times &color[0] }
color_map { |color| 8.times &color[8] }

puts ?\n, 'Color map:'
6.times do |green|
  color_map do |color|
    6.times do |red|
      6.times &color[16 + (red * 36) + (green * 6)] # blue
    end
  end
end

puts ?\n, 'Grayscale map:'
color_map { |color| 24.times &color[232] }