Focus on Curves and Surfaces | Focus On Curves and Surfaces (Focus on Game Development)

Kelly Dempski

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Acquisitions Editor: Mitzi Foster Koontz

Series Editor: Andr LaMothe

Project Editor/Copy Editor: Jenny Davidson

Technical Reviewer: Wolfgang Engel/Andr LaMothe

Interior Layout: Danielle Foster

Cover Designer: Mike Tanamachi

Indexer: Katherine Stimson

Proofreader: Sandi Wilson

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ISBN: 1-59200-007-X

Library of Congress Catalog Card Number: 2002111225

Printed in the United States of America

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To my Mother and Father

Acknowledgments

Thanks to my wife, Rachel. She has endured months of incredibly stimulating conversation about knot vectors and basis functions. I have a great appreciation for her patience, and this book would not have been possible without her support.

Thanks to my family for reasons too numerous to mention.

As always, many thanks again to my friends and colleagues Scott Kurth and Mitu Singh for their time spent proofreading, offering suggestions, and providing general moral support. For that, I consider myself extremely fortunate.

Thanks to everyone at Accenture Technology Labs for their support and encouragement. I have the pleasure to work with a group of extremely intelligent and thoughtful people.

Also, I'd like to thank all of the other people who worked on this book. I really appreciate the help of Mitzi Foster, Jenny Davidson, and many others. They are extremely supportive and tolerant of strange , longwinded e- mails . Many thanks go to Wolfgang Engel for his thoughtful and thorough technical editing.

I'd also like to thank the numerous people who have contributed to this field. Without their inventions , contributions, and insight, this book would quite literally have not been possible. It would be impossible to list all of the people who have explicitly or implicitly contributed to this field, but I have included a short bibliography in Appendix C that should serve to introduce you to their work.

Finally, I'd like to thank Ben, Tom, and Will at Bagel Art (highly recommended if you are ever in Evanston, IL), and Shaun, Mire, Ian, and all the people at Starbucks (highly recommended if you are ever on Earth).

All of the people mentioned above contributed in some way to the better aspects of this book. I deeply appreciate their contributions.

About the Author

KELLY DEMPSKI has been a researcher at Accenture Technology Labs for the past eight years . His research work has been in the areas of multimedia, Virtual Reality, Augmented Reality, and Interactive TV. He has authored several papers in these areas and is also the author of Real-Time Rendering Tricks and Techniques in DirectX by Premier Press.

LETTER FROM THE SERIES EDITOR

Ever since the world saw the undulating organic geometry in id Software's Quake III , everyone has been trying to add this powerful technique to their games . Both OpenGL and DirectX support higher-order surfaces, but it can be difficult to use them effectively. The real root of the problem is that this technology is mathematical in nature. It's not rocket science, but it's hard to use a "rational basis spline" when you don't know what those words mean.

With that in mind, my vision for this book was something that you can pick up and walk away with knowing exactly how to create 2D/3D curves and surfaces. The problem with this book is that you need someone who is a Jedi to write it; this material is complex, and only someone with years of experience in game programming, and years of experience in this area could pull it off-luckily for us, Kelly Dempski showed up with a proposal for this book that was exactly what I was looking for.

I am constantly saying how good all these Premier Game Development books are, and I am going to once again. This is the world's best book on the subject, hands down. There is simply nothing that is going to give you the information in an informal, but strict, fun, but serious way that balances what you need to know with the constraints of needing to know it within your lifetime <BG>.

I just finished reviewing the final text and demo of the book, and I have to say I am amazed The book starts off with an introduction about curves and surfaces, so you know what to expect, then Kelly (very wisely) creates a simple application framework to render curves and surfaces in a uniform manner (believe me when you start writing 50-100 demos for something, you want to be able to do it quickly). Once you have the tools to get started, then "it's on". Bezier curves are first up (being that I am French, I appreciate this of course), then B-splines (their close neighbors), and on to NURBS and subdivision curves. After all these topics have been covered, then it's round two with the 3D version of everything, and surfaces are also covered. So the transition is smooth and consistent with just enough math to get the job done, and there's a really nice calculus and vector review in the appendixes if you're a little rusty.

Finally, the book ends with some more advanced topics and delves into using DirectX 8.1+ to do all the math for us (for the most part), but like Kelly, I believe that you should know how to do this stuff-one day you might have to derive it all yourself!

In conclusion, this book rocks, and you have to have it. All the Internet articles in the world aren't going to give you what you will read in this book and immediately be able to leverage in your own work.

Sincerely,

Andr LaMothe
Premier Game Development Series Editor