Action Scrip Game Programing
Gary Rosenzweig 800 East 96th Street Indianapolis, Indiana 46240 USA ActionScript 3.0 Game Programming University Copyright © 2008 by Que Publishing All rights reserved No part of this book shall be reproduced, stored in a retrieval system, or transmitted by any means, electronic, mechanical, photocopying, recording, or otherwise, without written permission from the publisher No patent liability is assumed with respect to the use of the information contained herein Although every precaution has been taken in the preparation of this book, the publisher and author assume no responsibility for errors or omissions Nor is any liability assumed for damages resulting from the use of the information contained herein ISBN-13: 978-0-7897-3702-1 ISBN-10: 0-7897-3702-7 Library of Congress Cataloging-in-Publication Data: Rosenzweig, Gary ActionScript 3.0 game programming university / Gary Rosenzweig p cm ISBN 0-7897-3702-7 Computer games—Programming Computer animation ActionScript (Computer program language) I Title QA76.76.C672R73 2007 794.8'1526—dc22 2007028659 Printed in the United States of America First Printing: August 2007 Trademarks All terms mentioned in this book that are known to be trademarks or service marks have been appropriately capitalized Que Publishing cannot attest to the accuracy of this information Use of a term in this book should not be regarded as affecting the validity of any trademark or service mark Warning and Disclaimer Every effort has been made to make this book as complete and as accurate as possible, but no warranty or fitness is implied The information provided is on an “as is” basis The author and the publisher shall have neither liability nor responsibility to any person or entity with respect to any loss or damages arising from the information contained in this book or from the use of programs accompanying it Bulk Sales Que Publishing offers excellent discounts on this book when ordered in quantity for bulk purchases or special sales For more information, please contact U.S Corporate and Government Sales 1-800-382-3419 corpsales@pearsontechgroup.com For sales outside of the U.S., please contact International Sales international@pearsoned.com Associate Publisher Greg Wiegand Acquisitions Editor Laura Norman Development Editor Laura Norman Managing Editor Gina Kanouse Project Editor Anne Goebel Copy Editor Keith Cline Senior Indexer Cheryl Lenser Proofreader Heather Waye Arle Technical Editor Cheryl Brumbaugh-Duncan Publishing Coordinator Cindy Teeters Book Designer Anne Jones Senior Compositor Gloria Schurick Graphics William Follett Eve Park Contents at a Glance 10 11 12 Introduction Using Flash and ActionScript 3.0 ActionScript Game Elements Basic Game Framework: A Matching Game Brain Games: Memory and Deduction Game Animation: Shooting and Bouncing Games Picture Puzzles: Sliding and Jigsaw Direction and Movement: Space Rocks Casual Games: Match Three Word Games: Hangman and Word Search Questions and Answers: Trivia and Quiz Games Action Games: Platform Games Game Worlds: Driving and Exploration Game Index Contents Introduction Flash and Game Development Who Is This Book For? What Do You Need To Use This Book? Prerequisite Knowledge Software Applications Source Files Using the Example Games in Your Projects What You’ll Find in This Book The FlashGameU.com Website Using Flash and ActionScript 3.0 What Is ActionScript 3.0? Creating a Simple ActionScript Program A Simple Use of trace Creating Screen Output 12 Our First ActionScript 3.0 Class 13 Working with Flash CS3 15 Display Objects and Display Lists 16 The Stage 16 The Library 17 The Timeline 18 Writing and Editing ActionScript 19 ActionScript Game Programming Strategies 22 Single Class Method 22 Smallest Step Approach 22 Good Programming Practices 23 Basic ActionScript Concepts 26 Creating and Using Variables 26 Condition Statements 27 Loops 28 Functions 29 Testing and Debugging 29 Types of Bugs 29 Methods of Testing 30 Using the Debugger 31 Contents Publishing Your Game 33 Formats 33 Flash 34 HTML 35 ActionScript Game Programming Checklist 36 Publishing and Document Settings 36 Class, Function, and Variable Names 37 Runtime Issues 38 Testing Issues 39 ActionScript Game Elements 41 Creating Visual Objects 42 Using Movie Clips 42 Making Buttons 44 Drawing Shapes 47 Drawing Text 49 Creating Linked Text 51 Creating Sprite Groups 53 Setting Sprite Depth 55 Accepting Player Input 55 Mouse Input 55 Keyboard Input 56 Text Input 58 Creating Animation 59 Sprite Movement 59 Using Timers 61 Time-Based Animation 62 Physics-Based Animation 63 Programming User Interaction 65 Moving Sprites 65 Dragging Sprites 67 Collision Detection 68 Accessing External Data 69 External Variables 69 Loading Data 71 Saving Local Data 71 Miscellaneous Game Elements 72 Custom Cursors 72 Playing Sounds 74 Loading Screen 75 Random Numbers 76 v vi ActionScript 3.0 Game Programming University Shuffling an Array 77 Displaying a Clock 78 System Data 79 Game Theft and Security 80 Basic Game Framework: A Matching Game 83 Placing Interactive Elements 84 Methods for Creating Game Pieces 85 Setting Up the Flash Movie 86 Creating the Basic ActionScript Class 87 Using Constants for Better Coding 90 Shuffling and Assigning Cards 92 Game Play 95 Adding Keyboard Listeners 95 Setting Up Game Logic 96 Checking for Game Over 100 Encapsulating the Game 102 Creating the Game Movie Clip 103 Adding an Introduction Screen 104 Adding a Play Again Button 105 Adding Scoring and a Clock 106 Adding Scoring 106 Adding a Clock 109 Displaying Time 110 Displaying Score and Time after the Game Is Over 112 Adding Game Effects 113 Animated Card Flips 113 Limited Card-Viewing Time 116 Sound Effects 117 Modifying the Game 119 Brain Games: Memory and Deduction 121 Arrays and Data Objects 122 Arrays 122 Data Objects 124 Arrays of Data Objects 125 Memory Game 125 Preparing the Movie 126 Programming Strategy 127 Class Definition 128 Setting the Text, Lights, and Sounds 130 Playing the Sequence 133 Contents Switching Lights On and Off 134 Accepting and Checking Player Input 135 Modifying the Game 137 Deduction Game 138 Setting Up the Movie 139 Defining the Class 141 Starting a New Game 143 Checking Player Guesses 145 Evaluating Player Moves 146 Ending the Game 149 Clearing Game Elements 151 Modifying the Game 152 Game Animation: Shooting and Bouncing Games 155 Game Animation 156 Time-Based Animation 156 Coding Time-Based Animation 158 Air Raid 161 Movie Setup and Approach 162 Flying Airplanes 162 Moving Gun 166 Skyward Bullets 169 The Game Class 171 Modifying the Game 178 Paddle Ball 179 Setting Up the Movie 179 Class Definition 181 Starting the Game 183 Starting a New Ball 185 Game Animation and Collision Detection 186 Game Over 192 Modifying the Game 193 Picture Puzzles: Sliding and Jigsaw 195 Manipulating Bitmap Images 196 Loading a Bitmap 196 Breaking a Bitmap into Pieces 198 Sliding Puzzle Game 200 Setting Up the Movie 201 Setting Up the Class 201 Loading the Image 204 Cutting the Bitmap into Pieces 204 vii viii ActionScript 3.0 Game Programming University Shuffling the Pieces 206 Reacting to Player Clicks 209 Animating the Slide 211 Game Over and Cleanup 213 Modifying the Game 213 Jigsaw Puzzle Game 214 Setting Up the Class 214 Loading and Cutting the Image 216 Dragging Puzzle Pieces 219 Game Over 224 Modifying the Game 225 Direction and Movement: Space Rocks 227 Using Math to Rotate and Move Objects 228 The Sin and Cos Functions 228 Using Cos and Sin to Drive a Car 230 Calculating an Angle from a Location 233 Air Raid II 236 Altering the Gun 237 Changing the Bullets 239 Changes to AirRaid2.as 241 Space Rocks 242 Game Elements and Design 242 Setting Up the Graphics 244 Setting Up the Class 246 Starting the Game 248 Score and Status Display Objects 249 Ship Movement and Player Input 252 Shields Up! 256 Rocks 257 Missiles 261 Game Control 262 Modifying the Game 265 Casual Games: Match Three 267 Reusable Class: Point Bursts 268 Developing the Point Burst Class 269 Using Point Bursts in a Movie 273 Match Three 276 Playing Match Three 276 Game Functionality Overview 277 The Movie and MatchThree Class 278 Contents Setting Up the Grid 279 Player Interaction 282 Animating Piece Movement 285 Finding Matches 287 Finding Possible Moves 292 Score Keeping and Game Over 295 Modifying the Game 296 Word Games: Hangman and Word Search 297 Strings and Text Fields 298 ActionScript 3.0 String Handling 298 Applying Text Formatting to Text Fields 303 Hangman 309 Setting Up the Hangman 309 The Hangman Class 310 Word Search 313 Development Strategy 313 Defining the Class 315 Creating the Word Search Grid 316 User Interaction 320 Dealing with Found Words 323 Modifying the Game 326 10 Questions and Answers: Trivia and Quiz Games 327 Storing and Retrieving Game Data 328 Understanding XML Data 328 Importing External XML Files 330 Trapping Load Errors 332 Trivia Quiz 332 Designing a Simple Quiz Game 333 Setting Up the Movie 333 Setting Up the Class 334 Loading the Quiz Data 337 Message Text and Game Button 337 Moving the Game Forward 339 Displaying the Questions and Answers 340 Judging the Answers 342 Ending the Game 343 Deluxe Trivia Quiz 344 Adding a Time Limit 344 Adding Hints 347 Adding a Factoid 349 ix ... Introduction Using Flash and ActionScript 3.0 ActionScript Game Elements Basic Game Framework: A Matching Game Brain Games: Memory and Deduction Game Animation: Shooting and Bouncing Games Picture Puzzles:... and ActionScript 3.0,” introduces ActionScript 3.0 and some basic concepts such as game programming strategies and a checklist to help you develop games in Flash CS3 Chapter 2, “ActionScript Game. .. Rocks Casual Games: Match Three Word Games: Hangman and Word Search Questions and Answers: Trivia and Quiz Games Action Games: Platform Games Game Worlds: Driving and Exploration Game Index Contents