Processing

An Introduction to Programming

Jeffrey L. Nyhoff, Larry R. Nyhoff

• Publisher: Chapman and Hall/CRC
• Year: 2017
• Print ISBN: 9781482255959
• eBook ISBN: 9781351645225
• Topic: Computer Science
• Subtopic: Computer Graphics
• Index: Computer Science

This book demonstrates how Processing is an excellent language for beginners to learn the fundamentals of computer programming. Originally designed to make it simpler for digital artists to learn to program, Processing is a wonderful first language for anyone to learn. Given its origins, Processing enables a multimodal approach to programming instruction, well suited to students with interests in computer science or in the arts and humanities.

The book uses Processing's capabilities for graphics and interactivity in order to create examples that are simple, illustrative, interesting, and fun. It is designed to appeal to a broad range of readers, including those who want to learn to program to create digital art, as well as those who seek to learn to program to process numerical information or data. It can be used by students and instructors in a first course on programming, as well as by anyone eager to teach them self to program.

Following a traditional sequence of topics for introducing programming, the book introduces key computer science concepts, without overwhelming readers with extensive detail. The conversational style and pace of the book are based upon the authors' extensive experience with teaching programming to a wide variety of beginners in a classroom. No prior programming experience is expected.

CHAPTER 1

Basic Drawing in Processing

We’ll now put aside the advanced capability associated with the looping draw() function and Processing’s active mode that we explored at the end of the introduction. We will return instead to Processing’s simpler static mode and work through some simple examples of basic drawing in Processing. These examples will also give us the opportunity to take a closer look at some of the fundamentals of computer programming in general.

This chapter is not an exhaustive introduction to Processing’s extensive drawing capabilities. Rather, the goal is to give you enough of a foundation in drawing with Processing to understand the graphical examples in the chapters that follow.

Starting a New Program

In the Processing window, pull down the File menu and select New.

From now on, we will describe such a menu selection as File > New.

We now see a new Processing sketch window:

Saving a Program

When starting a new program, it is a good idea to save it promptly and then to save it frequently after making changes to the program. “Save early and often!” is how this strategy is sometimes stated. This is good advice that can help to spare you from losing work that you have done. Saving a program in Processing is very much the same process as saving your work in other software that you use. Select File > Save. Since this is the first time you are saving this program, the “Save sketch folder as…” dialog box appears.

Using this dialog, start by choosing the file folder location where you would like to save the Processing program that you are currently writing. By default, Processing will save all your sketches (programs) in a file location that is known as your Sketchbook. This Processing program setting that specifies this default Sketchbook file location can be changed if you plan to save your Processing programs in a different location.^* You can also just browse to the desired file folder location in the manner that you usually do when saving your work in other software programs that you use.

Next, in the File name textbox within the dialog box, enter a name for your program. It is customary to capitalize the first letter of a Processing program. Let’s name this example Drawing.

Then, click on the Save button to finish saving this program.

As a result, Processing creates a new folder in which your program is stored. This folder has the same name as that which you gave to your program. Thus, in this example, the new folder is named Drawing.

Processing calls this the sketch folder. If you examine the contents of ...

Table of contents

• Cover
• Half-Title
• Title
• Copyright
• Contents
• Foreword
• Preface: Why We Wrote This Book and For Whom It Is Written
• Acknowledgements
• Introduction: Welcome to Computer Programming
• Chapter 1 ▪ Basic Drawing in Processing
• Chapter 2 ▪ Types, Expressions, and Variables
• Chapter 3 ▪ More about Using Processing’s Built-In Functions
• Chapter 4 ▪ Conditional Programming with if
• Chapter 5 ▪ Repetition with a Loop: The while Statement
• Chapter 6 ▪ Creating Counting Loops Using the for Statement
• Chapter 7 ▪ Creating void Functions
• Chapter 8 ▪ Creating Functions That Return a Value
• Chapter 9 ▪ Arrays
• Chapter 10 ▪ Introduction to Objects
• INDEX