Visual basic game programming for teens

Visual Basic

R

Game

Programming for

Teens, Third

Edition

Jonathan S. Harbour

Course Technology PTR

A part of Cengage Learning

Australia . Brazil . Japan . Korea . Mexico . Singapore . Spain . United Kingdom . United States

Visual BasicR

Game Programming for Teens,

Third Edition

Jonathan S. Harbour

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Course Technology PTR: Stacy L. Hiquet

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Visual Basic is a registered trademark of Microsoft Corporation. Cover

art design created by Eden Celeste. All other trademarks are the

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eISBN-10: 1-4354-5811-7

For Kourtney

Many thanks to Emi Smith, Jenny Davidson, and Joshua Smith for their editing

and production efforts that led to this completed book. I am especially thankful to

Emi for giving me extra time to make this a labor of love rather than just another

book. I absolutely enjoyed this subject and trust the end result reflects the

attention that went into it.

Thanks to my wife, Jennifer, and our little ones, for your wonderful distractions.

When the first edition was published in 2004, we had only two: Jeremiah and

Kayleigh. By the time the second edition went to print in 2007, we had added two

more to our family: Kaitlyn and Kourtney. Some day when you read this, know

that you have filled my life with joy.

Much appreciation goes out to Eden Celeste for her beautiful character art fea￾tured on the cover and in several chapters—all of the hero and monster illus￾trations are hers. See her work at www.edenceleste.com. It seems like she can draw

anything I can imagine and always surprises me with her work.

I am grateful to Reiner Prokein for allowing me to use his extraordinary artwork,

which has made the examples in this book possible. His website, Reiner’s Tilesets,

is located at www.reinerstileset.de. I would not have even attempted to create a

role-playing game for this book had Reiner not made his artwork available in the

first place. The game artwork is all from Reiner.

Acknowledgments

Jonathan S. Harbour is a freelance writer, teacher, and indie game developer,

who has been programming video games since the 1980s. His first video game

system was an Atari 2600, which he disassembled on the floor of his room at age 9.

He has written on languages and subjects that include Cþþ, C#, Basic, Java,

DirectX, Allegro, Lua, DarkBasic, XNA Game Studio, Pocket PC, Nintendo GBA,

and game console hacking. He is the author of Visual C# Game Programming for

Teens; Beginning Java Game Programming, Third Edition; Beginning Game

Programming, Third Edition; Multi-Threaded Game Engine Design; and

Advanced 2D Game Development. His next project is The Complete XNA 4.0,

expected in early 2011. Visit his website at www.jharbour.com, which includes a

blog and game development forum.

About the Author

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiv

PART I BUILDING BLOCKS . .................................. 1

Chapter 1 Getting Started ................................. 3

What Is Game Programming Really All About? . . . . . . . . . . . . . . . . . 4

Get Your Feet Wet First, Ask Questions Later . . . . . . . . . . . . . . . 5

On Programming Languages . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Let Your Creativity Fly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

On Creativity, Talent, and Hard Work . . . . . . . . . . . . . . . . . . . . . . . 10

The Sky’s the Limit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Learn the Tricks of the Trade . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Taking a Look at Celtic Crusader . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Building a Role-Playing Game . . . . . . . . . . . . . . . . . . . . . . . . . . 14

The Story . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Describing the Player’s Character . . . . . . . . . . . . . . . . . . . . . . . . 16

Adventure Game or Dungeon Crawler? . . . . . . . . . . . . . . . . . . . 18

Level Up! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Chapter 2 Visual Basic Primer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

What Is Visual Basic? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

The .NET Framework . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Windows Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Contents

vi

Writing Your First Visual Basic Program . . . . . . . . . . . . . . . . . . . . . 24

Say Hello . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Code Editor Window . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Variables of All Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Using Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

What’s So Special about Strings? . . . . . . . . . . . . . . . . . . . . . . . . 35

Telling Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

Branching/Conditional Statements . . . . . . . . . . . . . . . . . . . . . . . . . 40

The If. . .Then Statement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

The Select. . .Case Statement . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

Guessing Game . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

Subroutines and Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Using Subs and Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Returning a Value . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Mathematical Operators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Converting Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Addition and Subtraction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Multiplication and Division . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

Math Quiz . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

Relational Operators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

Looping Statements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

For Loop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

Do Loops . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56

Arrays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

Structures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

Object-Oriented Programming . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

Encapsulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

Inheritance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

Polymorphism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

Classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

Level Up! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

Chapter 3 Forms and Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

Dice War . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

Form Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

Source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

Contents vii

Block Buster . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

Form Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

Source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

Tic-Tac-Toe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

Button Events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82

Source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84

Level Up! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

Chapter 4 Drawing with GDIþ . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

Drawing Lines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

PictureBox Is Our Friend . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

Surfaces and Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

4D Programming with a Timer . . . . . . . . . . . . . . . . . . . . . . . . . 93

Drawing Rectangles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93

Drawing Text . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96

Level Up! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98

Chapter 5 Bitmaps: Our First Building Block . . . . . . . . . . . . . . . . . . . 99

Dissecting Bitmaps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99

Loading a Bitmap File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100

Drawing a Bitmap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102

Rotating and Flipping a Bitmap . . . . . . . . . . . . . . . . . . . . . . . . 103

Accessing Bitmap Pixels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104

Creating a Game Class . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

Game Class Constructor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107

Game Class Destructor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108

Game Updates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108

Framework Demo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110

Level Up! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111

Chapter 6 Sprites and Real-Time Animation . . . . . . . . . . . . . . . . . . 113

What Is a Sprite? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114

Animating a Sprite . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117

Sprite Animation Theory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117

Creating a Sprite Class . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120

Sprite Drawing Demo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128

Improving the Game Class . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129

Separating Form and Module Code . . . . . . . . . . . . . . . . . . . . . 134

viii Contents

Adding a Real-Time Game Loop . . . . . . . . . . . . . . . . . . . . . . . 135

Gameplay Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137

Level Up! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139

Chapter 7 Collision Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141

Reacting to Solid Objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141

Rectangle Intersection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142

Collision Demo Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144

Sprite Class . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145

Game Class . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146

Form1 Class . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146

Level Up! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151

Chapter 8 Playing Sound Effects and Music . . . . . . . . . . . . . . . . . . 153

Programming Audio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153

Playing Wave Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155

Playing Wave Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156

The Audio Demo Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158

Using the Media Player Control . . . . . . . . . . . . . . . . . . . . . . . . . . 163

Referencing the Media Player . . . . . . . . . . . . . . . . . . . . . . . . . 163

Playing MP3 and MIDI Files . . . . . . . . . . . . . . . . . . . . . . . . . . . 164

Level Up! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166

PART II GAME WORLD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167

Chapter 9 Designing the Game of Celtic Crusader . . . . . . . . . . . . . 169

The Quest-Based Storyline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170

Designing the RPG World . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171

Map of the World . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171

Regions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175

The Player’s Character . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179

Character Attributes (Stats) . . . . . . . . . . . . . . . . . . . . . . . . . . . 180

Character Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181

Character Classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183

Non-Player Characters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 189

Weapons and Armor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 190

Magic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191

Contents ix

Communication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 192

Combat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 192

Level Up! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193

Chapter 10 Creating the Level Editor. . . . . . . . . . . . . . . . . . . . . . . . 195

Designing Our Own Level Editor . . . . . . . . . . . . . . . . . . . . . . . . . 196

Building the Editor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197

Creating a New Tilemap Level . . . . . . . . . . . . . . . . . . . . . . . . . 199

Loading and Saving Level Files . . . . . . . . . . . . . . . . . . . . . . . . 199

Level Up! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 202

Chapter 11 Rendering a Game Level . . . . . . . . . . . . . . . . . . . . . . . . 205

Mapping the Game World . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206

Tile-Based Ireland . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206

Loading and Drawing Level Files . . . . . . . . . . . . . . . . . . . . . . . 209

Introduction to Tiled Scrolling . . . . . . . . . . . . . . . . . . . . . . . . . . . 212

Constructing the Tiled Image . . . . . . . . . . . . . . . . . . . . . . . . . 214

Tile Buffer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214

Stepping Stones of the World . . . . . . . . . . . . . . . . . . . . . . . . . 215

Tile Rendering Theory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215

Per-Tile Scrolling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220

Full Tile Scrolling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220

Full-Tile Smooth Scrolling . . . . . . . . . . . . . . . . . . . . . . . . . . . . 223

Per-Pixel Scrolling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227

Sub-Tile Scrolling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227

Drawing the Scroll Buffer . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228

Aligning Tiles to the Scroll Buffer . . . . . . . . . . . . . . . . . . . . . . 228

Sub-Tile Scroll Buffering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 229

Sub-Tile Smooth Scrolling . . . . . . . . . . . . . . . . . . . . . . . . . . . . 231

Level Up! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235

Chapter 12 Adding Objects to the World . . . . . . . . . . . . . . . . . . . . 237

Adding Scenery to the Game World . . . . . . . . . . . . . . . . . . . . . . . 238

A New Game Loop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 238

New Level Class . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 243

Adding Trees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 247

x Contents

Adding an Animated Character . . . . . . . . . . . . . . . . . . . . . . . . . . 253

Level Up! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259

Chapter 13 Using Portals to Expand the World . . . . . . . . . . . . . . . . 261

Updating the Level Editor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 262

Perusing New Editor Features . . . . . . . . . . . . . . . . . . . . . . . . . 262

Creating a Portal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264

It’s a Data-Driven Game World . . . . . . . . . . . . . . . . . . . . . . . . . . . 265

Level Class Modifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 266

Teleporting to Another Dimension . . . . . . . . . . . . . . . . . . . . . 272

Looking for Tile Collisions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 274

Portal Demo Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 275

Adding Lua Scripting Support to the Game . . . . . . . . . . . . . . . . . 281

Installing LuaInterface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 281

Testing LuaInterface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 282

Sharing Tile Data with Lua . . . . . . . . . . . . . . . . . . . . . . . . . . . 286

Level Up! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287

PART III GAMEPLAY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 289

Chapter 14 Creating the Character Editor . . . . . . . . . . . . . . . . . . . . 291

Character Classes and Attributes . . . . . . . . . . . . . . . . . . . . . . . . . 291

Attributes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 292

Gaining Experience and Leveling Up . . . . . . . . . . . . . . . . . . . . 294

The Base Character Classes . . . . . . . . . . . . . . . . . . . . . . . . . . . 294

Peasants as Quest-Giving NPCs . . . . . . . . . . . . . . . . . . . . . . . . 299

The Enemy/Monster Classes . . . . . . . . . . . . . . . . . . . . . . . . . . . 300

The Character Editor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303

Loading Character Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 313

The Character Class . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 314

The Animated Character Artwork . . . . . . . . . . . . . . . . . . . . . . 319

Character Demo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 322

Level Up! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 324

Chapter 15 Dialogue: Talking with NPCs . . . . . . . . . . . . . . . . . . . . . 325

Talking with NPCs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 326

Creating the “Vendor” NPC . . . . . . . . . . . . . . . . . . . . . . . . . . . 326

Starting a Conversation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 326

Dialogue Choices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 332

Contents xi

Creating the Dialogue System . . . . . . . . . . . . . . . . . . . . . . . . . . . 333

Making Eye Contact . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 334

Dialogue GUI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 335

Final Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 345

Level Up! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 353

Chapter 16 Fighting, Getting XP, and Leveling Up . . . . . . . . . . . . . . 355

Preparing for Combat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 356

Starting an Attack . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 357

Combat Demo 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 358

Character Templates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 363

Animations : Player Characters (PCs) . . . . . . . . . . . . . . . . . . . . 364

Animations : Hostile NPCs . . . . . . . . . . . . . . . . . . . . . . . . . . . . 370

Animations : Friendly NPCs . . . . . . . . . . . . . . . . . . . . . . . . . . . 375

Creating the Combat System . . . . . . . . . . . . . . . . . . . . . . . . . . . . 376

Making Up Our Own Rules . . . . . . . . . . . . . . . . . . . . . . . . . . . 377

Spawning Enemy NPCs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 377

Attack Rolls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 378

Rolling for Damage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 381

Attack Roll Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 382

Dealing with the Player’s Death . . . . . . . . . . . . . . . . . . . . . . . 384

Combat Demo 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 385

Facing Your Enemies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 391

Which Way Did He Go? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 392

A Change of Character . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 393

State-Based Combat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 394

Dialogue Improvements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 395

Plugging in Attack State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 396

Dealing Permanent Damage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 399

Gaining Experience . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 402

Level Up! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 404

Chapter 17 Creating the Item Editor . . . . . . . . . . . . . . . . . . . . . . . . 405

Item Editor Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 406

Item Images . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 407

Looking Up Items . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 408

Item Class . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 408

Item Editor Source Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 414

Level Up! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 419

xii Contents

Chapter 18 Looting Treasure and Managing Inventory . . . . . . . . . . 421

Looting Treasure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 422

Preparing to Loot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 422

Stumbling Upon Loot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 424

Items Class . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 428

Character Class . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 430

Dropping Loot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 432

Managing Inventory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 436

Inventory Class . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 437

Player Class . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 446

Level Up! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 447

Chapter 19 Creating the Quest Editor . . . . . . . . . . . . . . . . . . . . . . . 449

Quests as Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 450

Pushing or Pulling? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 451

Quest Condition Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 451

Quest Rewards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 453

Quest Class . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 454

Quest Editor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 457

Quests as Story Driver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 460

Quests Class . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 461

Starting a Quest . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 463

Quest Window . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 464

Completing a Quest . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 465

Level Up! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 470

Chapter 20 So You Want to Be a Hero? . . . . . . . . . . . . . . . . . . . . . 471

Rolling Your Player Character . . . . . . . . . . . . . . . . . . . . . . . . . . . . 472

Scripting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 472

Binding Basic Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 473

Binding Lua Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 474

Loading and Saving the Game . . . . . . . . . . . . . . . . . . . . . . . . . . . 478

Saving . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 478

Loading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 480

Level Up! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 482

Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 483

Contents xiii

xiv

Imagine this: You create a new paladin character with random stats and hit

points, receive your first quest, and begin exploring the game world. You stumble

upon a skeleton warrior pacing near a pile of treasure. You attack the skeleton,

and it hits you back! You roll 1D20 and score a critical hit! The 20-point die, plus

dexterity, against the skeleton’s armor class, nets a guaranteed hit. Your damage

roll is 1D8 plus your strength and weapon modifier, which is 1D4, more than

enough to kill the monster! It falls to the ground, a jumble of bones. Lying next to

the unmoving skeleton is chain mail armor, which you pick up and equip, giving

your character a huge boost in armor points. You also pick up 10 gold coins and

gain 25 experience points. A magic key is also found, completing the first quest!

Now you dream of finding a better sword. Off to the right, you spot a whole group

of undead, the remains of a cursed Viking army, which surely have gear and gold

you could use . . . and you head toward them to battle!

This is no fictional narrative. You will learn to build a game with every feature just

described in detail! This book will teach you how to create your own fully

functional role-playing game (RPG) using Visual Basic. You will learn step-by￾step how to construct each part of the game engine using Windows Forms and

GDIþ, including a tiled scroller, game editors, and scripting. If you think role￾playing games are fun to play, wait until you start working on your very own

adventure! Constructing an RPG is more fun than playing one, because you are in

complete control over the game world, and you can let your imagination loose to

create adventures for others to enjoy. However, it is not easy! Just as your game

character must gain experience and level up, so must you level up by reading each

chapter to learn new skills!

Introduction