Ruby Ghostscript (RGhost) is a library for document developers wanting a quick and easy way to generate pdf files. It’s optimized to work with larger documents.

Notable features include: auto pagination, dynamic cursor, custom font tags, TTF and Type1 font support, virtual page(splitting into columns), image insertion, , text wrap, 32 barcodes, geometric shapes and vector drawing, EPS template support, PDF links, PDF password, Ruby on Rails data grid and multiple output formats.

Create a file with content

 doc=RGhost::Document.new
 doc.show 'Hello World' , :color => :blue
 doc.render :pdf, :filename => "hello.pdf"

RGhost Manual
RGhost RDOC
RGhost English Group
RGhost Grupo em Português

Both above are outdated, please see this wiki, it has been updating constantly …

RGhost Barcode
RGhost Rails

• About RGhost
  

• Installation Linux , MacOSX , Windows
  
• Environment Test
  
• Optional Configuration
• Using external fonts with Fontmap

• Basic usage
• Units
• Page Control
• Paper and Page Layout
• Fonts
• Defining and Using Tags
• Document and Callbacks
• Color RGB CMYK and Grayscale
• Object Orientation and Position
• PDF
  • PDF Security
  • PDF Hyperlink (Text and Rectangle)
  • PDF Document Info
  • PDF Quality
  • Converting PDF into other formats
• Zoom and Scale
• Graphic shapes
  • Changing defaults colors
  • Border
  • Lines
  • Rounded Corners, Frame, Rectangle and Square
  • Circle
  • Polygon
• Printing
• External Encoding (for Ruby 1.9)
• Printing text
• Printing text from file
• Virtual pages
• Working with templates and images
• Rails
  • Render for Rails and Sockets(inline)
  • Working with data and ActiveRecord

• Advanced
  • Postscript API's Internal Stack

• Constants
  • RGhost::Constants::Papers::STANDARD
  • Supported Devices, Drivers and Formats

• Version 0.8.7 – Every callbacks need a block variable

Ghostscript for Windows
RGhost Barcode