Can I get my README.textile into my RDoc with proper formatting?

I like to use Textile or Markdown to write readme files for my projects, but when I generate the RDoc the readme file gets interpreted as RDoc and looks really horrible. Is there a way to make RDoc run the file through RedCloth or BlueCloth instead of its own formatter? Can it be configured to autodetect the formatting from the file suffix? (e.g. README.textile gets run through RedCloth, but README.mdown gets run through BlueCloth)

Solution

Using YARD instead of RDoc directly will let you include Textile or Markdown files so long as their file suffixes are reasonable. I often use something like the following Rake task:

desc "Generate RDoc"
task :doc => ['doc:generate']

namespace :doc do
  project_root = File.expand_path(File.join(File.dirname(__FILE__), '..'))
  doc_destination = File.join(project_root, 'doc', 'rdoc')

  begin
    require 'yard'
    require 'yard/rake/yardoc_task'

    YARD::Rake::YardocTask.new(:generate) do |yt|
      yt.files   = Dir.glob(File.join(project_root, 'lib', '**', '*.rb')) + 
                   [ File.join(project_root, 'README.md') ]
      yt.options = ['--output-dir', doc_destination, '--readme', 'README.md']
    end
  rescue LoadError
    desc "Generate YARD Documentation"
    task :generate do
      abort "Please install the YARD gem to generate rdoc."
    end
  end

  desc "Remove generated documenation"
  task :clean do
    rm_r doc_dir if File.exists?(doc_destination)
  end

end