How to make my own render method

I would like to create method to render for my own format. What I would
like to accomplish is something like this:

  respond_to do |format|
    format.pdf { render :file :=> 'my_file' }

Where format.pdf is what I would like to accomplish. I guess I must do
two things:

1. Register new format (format.pdf)
2. Implement rendering method.

Can someone please direct me where should I begin. I don't seem to find
any good (easy) directions on the net.


You might want to look into “prawn” and “prawnto”.