Table of Contents

• 1. Welcome
• 2. What is PostScript?
  • 2.1. Key Features
  • 2.2. History
• 3. Documentation Sections
  • 3.1. PostScript Levels
  • 3.2. Language Syntax
  • 3.3. Usage Guides
    • 3.3.1. Basic Usage
    • 3.3.2. Advanced Usage
  • 3.4. Command Reference
  • 3.5. Practical Examples
  • 3.6. Glossary
• 4. Quick Start
  • 4.1. Hello World
  • 4.2. Basic Drawing Example
• 5. Additional Resources
  • 5.1. Official Documentation
  • 5.2. External Resources
• 6. Contributing

A comprehensive, searchable reference guide for the PostScript programming language, covering operators, syntax, language levels, and practical usage patterns.

1. Welcome

PostScript is a page description language developed by Adobe Systems. It is a dynamically typed, concatenative programming language and was the first device-independent page description language. This reference guide provides detailed documentation for PostScript operators, syntax rules, and practical programming techniques.

2. What is PostScript?

PostScript is a stack-based, interpreted programming language created by Adobe Systems in 1984. It was designed to describe the layout and graphics of a page in a device-independent way, making it the foundation for desktop publishing and electronic document distribution.

2.1. Key Features

• Device Independence: PostScript programs produce the same output on any PostScript-compatible device

• Stack-Based Architecture: Operations work with a last-in-first-out stack model

• Turing Complete: Full programming language with control structures, procedures, and data types

• Vector Graphics: Native support for scalable vector graphics and typography

• Imaging Model: Sophisticated graphics model supporting paths, fills, strokes, and clipping

2.2. History

Year	Milestone
1984	PostScript Level 1 released by Adobe Systems
1990	PostScript Level 2 introduced color extensions and improved performance
1996	PostScript 3 (Level 3) added advanced features including smooth shading and better PDF integration
1993-Present	PDF (Portable Document Format) emerges as a derivative of PostScript for document exchange

3. Documentation Sections

3.1. PostScript Levels

Learn about the evolution of PostScript through its three major versions:

• PostScript Level 1 - The original specification

• PostScript Level 2 - Color and composite fonts

• PostScript Level 3 - Advanced imaging features

• Version Comparison - Feature comparison across levels

3.2. Language Syntax

Understanding PostScript’s unique syntax and data structures:

• Tokens - Basic lexical elements

• Objects - Data types and object model

• Operators - Built-in operations

• Procedures - Executable arrays and user-defined functions

• Arrays - Ordered collections

• Dictionaries - Key-value associations

• Strings - Text and binary data

• Data Types - Complete type system

3.3. Usage Guides

3.3.1. Basic Usage

Essential concepts for PostScript programming:

• Stack Operations - Working with the operand stack

• Coordinate Systems - User space and device space

• Graphics State - Managing rendering parameters

• Path Construction - Building vector shapes

• Painting Operations - Filling and stroking paths

3.3.2. Advanced Usage

Advanced features and techniques:

• Fonts and Text - Typography and text rendering

• Color Spaces - Color models and management

• Patterns - Tiling patterns and textures

• Forms - Cached graphical objects

• Images - Raster image handling

• Device Control - Output device management

• File Operations - File I/O and streams

• Error Handling - Exception management

• Resource Management - Memory and resources

3.4. Command Reference

Complete reference for all PostScript operators, organized by category:

• by category

3.5. Practical Examples

Real-world code examples and use cases:

• Hello World - Your first PostScript program

• Drawing Shapes - Creating vector graphics

• Text Layout - Working with fonts and text

• Color and Gradients - Advanced color techniques

• Image Manipulation - Working with raster images

• PDF Generation - Creating PDF documents

3.6. Glossary

Definitions of PostScript-specific terminology and concepts.

4. Quick Start

4.1. Hello World

Here’s a simple PostScript program that displays "Hello, World!":

%!PS-Adobe-3.0
%%Title: Hello World
%%Creator: PostScript Language Reference Guide
%%Pages: 1
%%EndComments

/Helvetica findfont    % Find the Helvetica font
12 scalefont           % Scale to 12 points
setfont                % Set as current font

72 720 moveto          % Position at 1 inch from left, 10 inches from bottom
(Hello, World!) show   % Display the text

showpage               % Output the page
%%EOF

4.2. Basic Drawing Example

Creating a simple rectangle:

%!PS-Adobe-3.0

newpath                % Start a new path
100 100 moveto        % Move to starting point
200 0 rlineto         % Draw line 200 points right
0 150 rlineto         % Draw line 150 points up
-200 0 rlineto        % Draw line 200 points left
closepath             % Close the path

0.5 setgray           % Set gray level to 50%
fill                  % Fill the rectangle

showpage              % Output the page
%%EOF

5. Additional Resources

5.1. Official Documentation

• PostScript Language Reference Manual (PLRM) - The official specification

• PostScript Language Tutorial and Cookbook

5.2. External Resources

• PostScript on Wikipedia

• Ghostscript - Open source PostScript interpreter

• Adobe PostScript Information

6. Contributing

This documentation is open source and welcomes contributions. See our GitHub repository for:

• Reporting errors or omissions

• Suggesting improvements

• Adding examples

• Correcting documentation

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This reference guide is maintained by the Claricle community.