Color Palette Generator in Ruby

README.md

Color Palette Generator

Ever have a list of colors and want to find out what they look like without plopping them all into GIMP/Photoshop?

This script will take an argument, a comma-separated list of color hashes (be sure to quote if your shell uses # for comment), and generates a quick HTML document for showing what the colors look like, in a table:

color sample | color code

Usage is: ruby colorpalette.rb '#000000,#111111,#222222,#333333,#444444' > out.html

Authored by @CodeBlock, Licensed GPLv2+.

colorpalette.rb

#!/usr/bin/env ruby
# Take a comma-separated list of colors and create an html table to sample them.
# Be sure to quote the colors given on the CLI because # will act as comment in
# in bash.
# Written by Ricky Elrod, ricky@elrod.me
# GPLv2+

if ARGV.empty?
  puts "Usage: #{$0} '#list,#of,#color,#codes'"
  exit 1
end

# This is a bit hackish, but it does this:
# - Split the input up by commas.
# - If the input is #rgb instead of #rrggbb, convert it to the latter.
# - Take the rr, gg, bb values, convert them to integers, and add them up
# - Store the result in color_hsh
color_hsh = {}
ARGV[0].downcase.gsub(' ', '').split(',').uniq.each do |color|
  if color.length == 3
    # This is 1-based because we expect to start with a #
    color_rgb = '#' + color[1]*2 + color[2] * 2 + color[3] * 2
  else
    color_rgb = color
  end

  total = color_rgb.sub('#', '').scan(/.{2}/).inject { |sum, octet| sum.to_i + octet.to_i(16) }
  color_hsh[color_rgb] = total    
end

# This converts color_hsh into an array of colors, sorted from dark to light.
colors = color_hsh.sort_by { |k,v| v }.collect { |a| a[0] }

puts '<style>'
puts '  body { font-family: monospace; }'
puts '  td { width: 200px; }'
colors.each_with_index do |color, index|
  puts "  .color#{index} { background-color: #{color}; }"
end
puts '</style>'

puts

puts '<table>'
puts '  <tr>'
puts '    <th align="left">Color Sample</th>'
puts '    <th align="left">Color Code</th>'
puts '  </tr>'
colors.each_with_index do |color, index|
  puts '  <tr>'
  puts "    <td class='color#{index}'></td>"
  puts "    <td>#{color}</td>"
  puts '  </tr>'
end
puts '</table>'