Photoshop: Export Layer Comps

Web designers, in particular, are famous for making Photoshop files with 134 layers, all named “Layer 2 copy copy copy copy”, and spending an hour turning them on and off to show you one iteration of their handiwork. Using Photoshop and not using layer comps is akin to chartering a Gulfstream jet – and then taxiing to your destination.

This script will save all your layer comps separately, in a format of your choosing. “But,” I hear you cry, “Photoshop already comes with a script that already does that already”. Yes, but this one uses the magnificent “Save for Web” command, which performs superior squishing and optimising.

Download Export-layer-comps.rb.zip.

The source code is rubbing its sleepy eyes and yawning, just over there.

#!/usr/bin/env ruby

# rb-appscript script by Ian Haigh (http://ianhaigh.com/)
# Mon Dec 14 10:32:32 EST 2009

# This is a quick & easy way to export all your layer comps to individual
# files. One advantage of this technique is that it uses the "Save for Web…"
# command, which (in my experience) generates smaller, higher quality web
# graphics.

require 'rubygems'
require 'optparse'
require 'appscript'
require "osax"

sa = OSAX.osax('StandardAdditions')

ps = Appscript.app('Adobe Photoshop CS4.app')
finder = Appscript.app("Finder.app")

begin
	comps = ps.current_document.layer_comps.get
rescue Exception => e
	sa.display_alert("Please open a document with at least two layer comps.", :as => :critical )
	exit
end

# Save them into the same directory.
# (This could be modified so the user can choose where to save the files)

begin
	dir = File.dirname(ps.current_document.file_path.get.to_s)
rescue Appscript::CommandError => e
	sa.display_alert("Please ensure the document is saved before running this script.")
	exit
end

format = sa.choose_from_list(
	%w{ jpg png psd },
	:with_title => "Export layer comps",
	:with_prompt => "Choose a format",
	:default_items => ["jpg"],
	:multiple_selections_allowed => false,
	:empty_selection_allowed => false
)[0]

# loop through each comp, applying and saving it as we go
comps.each do |c|
	ps.apply(c)
	file_name = File.basename(ps.current_document.name.get, ".*") + "_" + c.name.get

	case format
	when "jpg"
		ps.export(ps.current_document, :in => "#{dir}/#{file_name}.jpg", :as => :save_for_web,
			  :with_options => {:web_format => :JPEG, :quality => 90})
	when "png"
		ps.export(ps.current_document, :in => "#{dir}/#{file_name}.png", :as => :save_for_web,
			  :with_options => {:web_format => :PNG, :png_eight => true})
	when "psd"
		ps.save(
			ps.current_document,
			:in => "#{dir}/#{file_name}.psd",
			:as => :Photoshop_format,
			:appending => :lowercase_extension,
			:copying => true,
			:with_options => {
				:save_layers => false
			}
		)
	end
end

finder.open(MacTypes::Alias.path(dir))
finder.activate