$sudo aptitude install libcairo-ruby libpango1-ruby librsvg2-ruby libpoppler-glib-ruby
$sudo gem install pdf-wrapper

#require 'rubygems'
require 'pdf/wrapper'
 
  def generate_pdf(options={})
    pdf = PDF::Wrapper.new(options)
    pdf.text "สวัสดี ภาษาไทย"
    pdf.render_to_file("test.pdf")
  end
 
 paper = {:paper => :A4}
 generate_pdf(paper)

>
class PdfsController < ApplicationController
 
  require 'pdf/wrapper'
 
  def index
    paper = {:paper => :A4}
    generate_pdf(paper)
  end
 
  def generate_pdf(options={})
    pdf = PDF::Wrapper.new(options)
    pdf.set_color(:black)
    pdf.text "สวัสดี ภาษาไทย"
    pdf.render_to_file("test.pdf")
  end
 
end
</blockcode>