Adventures in Python

Craig Richardson is a software developer, freelance writer, and former teacher with plenty of classroom experience. In his spare time, he has introduced hundreds of beginners to programming through his fun and engaging Python workshops and resources.

Introduction 1

Adventure 1

Diving into Python 23

What Is Programming? 24

Opening IDLE 25

Returning to Your First Python Program 26

It Isn’t Working—Grrr! 28

Using a File Editor 30

Asking Questions with Variables 33

A Bit About Variables 35

Using Variables for a Fill-in-the-Blanks Story 37

Making the Program Make Decisions: Conditionals 39

Using if Statements 39

Nested if Statements 41

Creating an Imaginary Vending Machine 43

Repeating Code with Loops 45

Using while Loops 45

Infinite while Loops 47

Praise Generator 48

A Bigger Adventure: Spaceship Control Console 50

Set-Up and Password 50

Using the Console to Do Things 52

Adventure 2

Drawing with Turtle Graphics 57

Getting Started with Turtle 57

Using Variables to Change Angles and Lengths 61

Using Addition to Draw a Spiral 64

Saving Some Space with Loops 65

A Shape with 360 Sides: Drawing a Circle 67

Controlling the Number of Sides Using for Loops 68

Changing the Fill Colour in a Shape 71

Creating Functions to Reuse Your Code 72

Shape Presets 75

Adding Randomly Generated Pictures 76

Adventure 3

Windows, Buttons, and Other GUI Stuff 83

Creating Buttons 84

Changing the Button Text on Click 87

Counting Clicks 88

Creating Text Boxes 90

Writing It Backwards 92

Adding Passwords 93

Building a Random Sentence Generator 96

Programming a Guessing Game 99

Adventure 4

More GUI Elements with Tkinter 105

Creating Sliders 105

How Colours Work on Computers and as Hexadecimal Values 109

Changing the Canvas Colour 111

Making the Colour Picker 113

Adding a Text Box 116

Creating a Click Speed Game 117

Adventure 5

Drawing Shapes with PyGame 123

Installing PyGame 123

My First PyGame 124

Creating Rectangles 127

Creating a Rectangle 127

A Rainbow of Rectangles 128

Colour Grid 131

Creating Ellipses 133

Wobbling Circle 133

Saving Your Images 135

Saving a Single Image 135

Saving a Series of Images 136

Adventure 6

Adding Keyboard Input with PyGame 139

Using Keyboard Input 140

Other Keys You Can Use 142

Creating the Game 142

Introducing Full Movement 146

Moving the Player Offscreen 148

Adding the Ball 150

Creating Collisions 152

Goal! 154

Adding a Time Limit 157

Adventure 7

Creative Ways to Use a Mouse with PyGame 161

Getting the Mouse Position 161

Making a Button 163

Moving Target 166

Exploding Clicks 169

Making a Mesh 172

Creating Mouse Trails 175

Adventure 8

Using Images with PyGame 181

Loading an Image 181

Layering Images 184

Randomly Layering Images 186

Adding a Moustache to a Photograph 188

Making Sprites 191

Creating a Walking Animation 191

Walking in All Directions 195

Teleportation 197

Adventure 9

Using Sounds and Music with PyGame 203

Playing Sounds 203

Creating a Noise Loop 205

Making Keyboard Sound Effects 207

Using Music with Python 210

Playing Music 210

Adding Volume Tremolo 212

Making a Music Player 215

Adding Sounds and Music to a Game 218

Adventure 10

Your Really Big Adventure 223

Writing the Program for the Game 224

Setting Up the Files 224

Making the Game 225

Walls 226

Doors, Collisions and Coins 229

Setting Up the Window and Variables 231

Adding the Game Loop 234

Character Controls and Animations 234

Player Collisions and Collecting Coins 237

Displaying Points and Updating the Window 237

Playing the Game 238

Debugging the Game 239

Summary 240

Appendix A

Installing and Downloading the Proper Files 243

Installing PyGame 243

Windows 8 243

Windows 7 245

Mac 245

Linux (Ubuntu) 247

Raspberry Pi 248

Downloading the Files for Adventures 8, 9 and 10 248

Windows 8 248

Windows 7 249

Mac 249

Linux (Ubuntu) 250

Raspberry Pi 250

Glossary 251

Index 257