Allison Parrish - Getting Started with Processing.py: Making Interactive Graphics with Pythons Processing Mode

by Allison Parrish , Ben Fry , and Casey Reas

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• May 2016: First Edition

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Processing.py is an interactive programming and graphics framework for the Python programming language. Jonathan Feinberg created Processing.py in 2010, basing his work on an existing programming framework called Processing, created by Casey Reas and Ben Fry in 2001. Casey and Ben were inspired by how simple it was to write interesting programs with the languages of their childhood (Logo and BASIC), and intended their framework to be a way to sketch (prototype) full-screen, interactive software without the frustration of languages typically used for this purpose at the time (C++ and Java).

When the Processing project was first created, it was intended to be a language-agnostic, arts-oriented approach to interactive programming, taking inspiration from OpenGL, PostScript, and Design By Numbers, among other sources. Although early versions of Processing were compatible with the Python programming language, a decision was made to focus the teams limited resources on a Java-based syntax. Jonathan Feinbergs Processing.py project restored Python compatibility to the project. (For more information on the relationship between Processing, Processing.py, and Python, see .)

Processing was designed to be an ideal environment for teaching design and art students how to program and to give more technical students an easier way to work with graphics. The combination is a positive departure from the way programming is usually taught and, since 2001, Processing has been at the center of a growing movement to promote software literacy in the visual arts and visual literacy within technology.

Im a strong believer in the power of the Python programming language and have taught Python with great success to novice programmers in many disciplines, from software engineering to the humanities to the arts. For this reason, I was overjoyed when Casey and Ben approached me to help write this book, which brings together their time-tested creative coding framework with a programming language Ive found so friendly and productive for novice coders and experts alike. We believe that Processing.py is not just a great framework for learning how to program but an invaluable addition to the toolbox of Python programmers of all stripes who need a simple and clear means of making interactive applications.

This book is available in three slightly different versions. One version is an introduction to Processing using its traditional, Java-based syntax, and a second covers p5.js, a version of Processing reinterpreted for todays Web. The version you now have in your possession introduces Processing with the Python programming language, using Processing.py as the bridge between the two. The three books are organized in very similar ways, and much of the content is identical from one book to the other. The main difference, of course, is that the code examples in this book are all written in Python. This book also contains some additional information and educational material about Python-specific techniques, idioms, and data structures. We believe this book will work well as an introductory text for the Processing Development Environment, the Python programming language, and interactive programming in general.

We hope youll have fun with this book and be inspired to continue programming. Lets begin!