Processing : an introduction to programming

571 Pages·2017·11.691 MB·English

by  Nyhoff, Jeffrey, Nyhoff, Larry R

Processing: An Introduction
to Programming

Processing: An Introduction
to Programming
by
Jeffrey L. Nyhoff
Larry R. Nyhoff
CRC Press
Taylor & Francis Group
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Library of Congress Cataloging‑ in‑ Publication Data
Names: Nyhoff, Jeffrey, author. | Nyhoff, Larry R., author.
Title: Processing : an introduction to programming / Jeffrey L. Nyhoff, Larry
R. Nyhoff.
Description: Boca Raton : CRC Press, 2017.
Identifiers: LCCN 2016041238 | ISBN 9781482255959 (pbk. : alk. paper)
Subjects: LCSH: Processing (Computer program language) | Computer
programming--Study and teaching.
Classification: LCC QA76.73.P75 N94 2017 | DDC 005.1071--dc23
LC record available at https://lccn.loc.gov/2016041238
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Contents
Foreword, xv
Preface: Why We Wrote This Book and For Whom It Is Written , xvii
Acknowledgments, xxi
Introduction: Welcome to Computer Programming, xxiii
Chapter 1 ▪  Basic Drawing in Processing 1
Starting a New Program 1
Saving a Program 2
Retrieving a Program 3
Entering Code into the Text Editor 4
Basic Drawing with Graphical Elements 8
Setting the “Canvas” Size: A Closer Look at the size() Function 8
Drawing Points: The point() Function 10
Drawing Line Segments: The line() Function 11
Drawing Rectangles: The rect() Function 13
Drawing Ellipses: The ellipse() Function 17
Drawing Triangles: The triangle() Function 20
Drawing Quadrilaterals: The quad() Function 22
Drawing Arcs: The arc() Function 26
Summary 29
The Processing Reference 31
More about Graphical Elements 31
Stacking Order 32
Changing Line Thickness: The strokeWeight() Function 33
Working with Color: RGB 35
Resetting the Canvas: The background() Function 37
vii
viii ◾ Contents
Changing the Fill Color: The fill() and noFill() Functions 38
Changing the Stroke Color: The stroke() and noStroke() Functions 41
Inline Comments 43
Grayscale 43
Transparency 45
Summary 46
Exercises 47
Chapter 2 ▪  Types, Expressions, and Variables 53
Values 53
Numeric Values 53
Integers: The int Type 54
Numbers with Decimal Points: The float Type 54
Arithmetic with int Values and float Values 54
int Arithmetic 55
Integer Division 56
Calculating the Remainder with the Modulo Operator: % 57
float Arithmetic 58
float Fractions 59
The Trouble with Fractions on Computers 60
Evaluating Expressions 63
Order of Operations 63
Using Parentheses 65
Variables 65
Predefined Variables: width and height 67
Benefits of Using Variables 72
Creating and Using Our Own Variables 73
Variable Names 74
Variable Types 75
Declaring a Variable 76
Assigning a Value to a Variable 77
Combining Declaration and Initialization 80
Reusing a Variable 80
Type Mismatches 83
Why Not Use Only the float Type? 87
Expressions in Assignment Statements 88
Contents   ◾   ix
Using a Variable on the Right-Hand Side of an Assignment Statement 91
Being Careful with Integer Division 95
Reassigning a New Value to a Variable 98
Constants 106
Predefined Constants 106
Defining Our Own Constants 108
Nonnumeric Types 110
Individual Characters: The char Type 110
Multiple Characters: The String Type 114
String Concatenation 116
Summary 118
Exercises 119
Chapter 3 ▪ More about Using processing’ s Built-In Functions 125
More about Console Output: The print() and println() Functions 125
Displaying Multiple Items to the Console 126
Graphical Text in Processing 127
The text() Function 128
The textsize() Function 128
The textAlign() Function 129
Matching the Type of an Argument to the Type of a Parameter 130
Two Kinds of Functions 132
void Functions 132
Functions That Return a Value 134
Determining a Function’ s Return Type Using Processing’ s Reference 137
Example: Calculating a Hypotenuse with the sqrt() Function 138
The pow() Function 140
Calculating the Area of a Square Using the pow() Function 141
Calculating the Hypotenuse with the pow() Function 144
The random() Function 145
The round() Function 146
Using the round() Function 147
More Conversion Functions: int() and float() 147
int() and random() Example: Choosing a Random Integer to
Simulate Rolling a Die 148
int() and random() Example: Random Side Length for a Square 149