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Information to Users INFORMATION TO USERS This manuscript has been reproduced from the microfilm master. UMI films the text directly from the original or copy submitted. Thus, some thesis and dissertation copies are in typewriter face, while others may be from any type of computer printer. The quality of this reproduction is dependent upon the quality of the copy sulwnltted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleedthrough, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did riot send UMI a complete manuscript and there are missing pages, these will be noted. Also, If unauthorized copyright material had to be removed, a note will indicate the deletion. Oversize materials (e.g., maps, drawings, charts) are reproduced by sectioning the original, beginning at the upper left-hand comer and continuing from left to right in equal sections with small overlaps. Photographs included in the original manuscript have been reproduced xerographlcally in this copy. Higher quality 6" x 9" black and white photographic prints are available for any photographs or illustrations appearing in this copy for an additional charge. Contact UMI directly to order. ProQuest Information and Learning 300 North Zeeb Road, Ann Arbor, Ml 48106-1346 USA 800-521-0600 UMÏ Creating Continuous Design Spaces for Interactive Genetic Algorithms with Layered, Correlated, Pattern Functions DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By Matthew Lewis, B.A., B.S.E., M.S. ***** The Ohio State University 2001 Dissertation Committee: Approved by Richard Parent, Adviser Wayne E. Carlson Adviser John R. Josephson Department of Computer and Information Science UMI Number: 3031222 UMI’ UMI Microform 3031222 Copyright 2002 by Bell & Howell Information and Learning Company. Ail rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. Bell & Howell Information and Learning Company 300 North Zeeb Road P.O. Box 1346 Ann Arbor, Ml 48106-1346 © Copyright by Matthew Lewis 2001 ABSTRACT Interactive evolutionary design (lED) is a design paradigm that can be used to generate computer graphics content by means of artificial evolution. Traditional evo­ lutionary design research relies on objectively computable fitness functions to evaluate the quality of individuals in a population of potential solutions to a design problem. lED systems rely instead on subjective judgment to determine fitness. Most implementations of lED systems demonstrate significant signature. The term signature refers to the lack of visual diversity in the populations and individuals generated by lED systems. Signature is primarily the result of the solution space rep­ resentation. Frequently, primitives and techniques are used which are not sufficiently general, or are biased towards specific visual qualities. In practice, such systems are only able to access a small region of a problem domain’s ideal potential solution space. Alternatively, too general a representation is used, resulting in the need to search too large a region of solution space. This makes it impractical for an interactive system to be used to find fit individuals. One of the most common uses of lED is the generation of nonrepresentational images, usually either for artistic purposes or for use as textures or surface shaders. Focusing on this problem domain, continuous pattern functions are introduced and used as a new genetic primitive in an evolutionary design context. Abstracted from 11 pattern based procedural texturing^ techniques, continuous pattern functions are de­ fined in order to produce a wide range of patterns and forms for generating images and surfaces. Their fiexibility enables greater visual diversity and control of visual attributes than has previously been demonstrated in lED image systems. Formal graphic design knowledge is integrated into continuous pattern functions to further increase the visual diversity of generated populations. Finally, layer-based cloning methods are introduced to address the “s^mchronization problem” of smoothly facil­ itating feature correlation. m This is dedicated to my wife, Beth. IV ACKNOWLEDGMENTS I have reached this point because of many, many people who have had an impact on my life and education. First, thanks must be given to my advisor Rick Parent. Computer Graphics is a huge field and Rick has stuck by me patiently through my many changing research interests. Thanks also to the other members of ray commit­ tee, Wayne Carlson and John Josephson. They have been generous with their time « and advice. It has been a privilege to work with each of them. My gratitude also goes to Wayne for all of the wonderful opportunities he has given me over the years I’ve worked at ACC AD. I’ll always appreciate and remember the concern he expressed about whether I’d finish my Ph.D. while considering whether to hire me for a staff position. Thanks also to Maria Palazzi for her ongoing trust and encouragement. Her tireless enthusiasm and drive are a constant source of inspiration. My fellow Supercomputer Graphics Research Specialists, Steve Spencer, Steve May, and Pete Carswell have helped and taught me a great deal over the years. They, along with the rest of the ACCAD staff, AHne, Barb, Bob, Charlotte, Elaine, Jeff, Midori, Mike, Phil, Ruedy, Suba, Traci, and Viki, have all made this a fantastic environment to work in. There are many, many students that I have spent countless hours with at CIS and ACCAD over the past decade. I have learned so much teaching, working, and hanging out with you all. Just a few of these include: Alex, Barb, Beth, Brandon, Breit, Carl, Charles, Chris, Clarke, Craig, Dave, Ed Sindelar, Ed Swan, Erika, Ferdr, Flip, Hae-jeon, Heath, Ian, Janet, John, Jon, Julie, Karan, Kevin G, Kevin R, Kevin S, KT, Leslie, Liza, Markus, Matt B, Matt C, Meg, Melissa, Michelle, Miho, Moon, Muqeem, Nathania, Pete H, Pete S, Rick, Roxie, Scott K, Scott S, Sonia, Todd, Tom, Tony, Tonya, Torsten, Vita, VVobbe, and Wooksang. Very special thanks to Matt Beitler, Cory Bowman, Peter Gerstmann, Cheryl Klepser, Neal McDonald, Greg Rapp, Dave Reed, Todd Sines, and Lawson Wade for many long hours spent contemplating life’s mysteries. Each of you have provided inspiration and support in many different ways. A number of teachers and faculty have given me opportimities, challenges, insights, and friendship. Without people like them I never would have made it this far. Some of them include Norm Badler, Mary Coif, Chuck Csuri, Carol Gigliotti, Mary Gregg, Ken Gross, Bettie Kelly, Ruth King, Laura Lisbon, Tom Saiers, and Bob Schwartz. Antoine Durr, Gary Greenfield, Ray Davis, and the staff of Side Effects have provided advice and assistance with numerous technical challenges. Of course my family are most responsible for who I am today. Infinite thanks to my mother, father, Amy, and Jennifer for their unwavering love, encouragement, and support. Vincent and Simon are two amazing fountains of endless love, potential, and surprise (how it is that T managed to be chosen to be Daddy for the most incredible boys on the face of the earth?) Most of all I must express eternal gratitude to Beth for her patience, intelligence, and love. Thanks for choosing me. VI VITA March 21, 1969 ................................................. Born - Doylestown, PA, USA 1991 .................................................................... B.A. Philosophy 1991 .................................................................... B.S.E. Computer Science Engineering 1993 .....................................................................M.S. Computer Information Science 1993-present .......................................................Graphics Research Specialist, The Advanced Computing Center for the Arts and Design (ACCAD), The Ohio State University. PUBLICATIONS Research Publications Lewis, Matthew. “Visual Aesthetic Evolutionary Design”, on CD accompanying Creative Evolutionary Systems, Peter J. Bentley and David W. Corne, eds. Morgan Kaufman, 2001. Lewis, Matthew. A Comparison of Parametric Contour Spaces for Interactive Ge­ netic Algorithms. OSU-ACCAD-6/Ol-TRl, The Ohio State University, Advanced Computing Center for the Arts and Design, 2001. Lewis, Matthew. “Aesthetic Evolutionary Design with Data Flow Networks” in Proceedings of Generative Arts 2000, Milan, Italy, ed. Celestino Soddu, December, 2000. YU Lewis, Matthew. An ImpKcit Surface Prototype for Evolvmg^ Humarr Figure-Geonr- etry. OSU-ACCAD-11/00-TR2, The Ohio State University, Advanced Computing Center for the Arts and Design, 2000. Lewis, Matthew. Evolving Human Figure Geometry. OSU-ACCAD-5/OO-TRl, The Ohio State University, Advanced Computing Center for the Arts and Design, 2000. Lewis, Matthew. Sanbaso: A Web Based VRh/IL Humanoid Animation Tool. OSU- ACCAD-10/97-TR1, The Ohio State University, Advanced Computing Center for the Arts and Design, 1997. Carlson, Wayne, Stephen Spencer, Margaret Geroch, Matthew Lewis, Keith Bed­ ford, David Welsh, John Kelley, and Arun Welch. Visualization of Results from Distributed, Coupled Supercomputer-Based Mesoscale Atmospheric and Lake Mod­ els Using the NASA ACTS. OSU-ACCAD-7/95-TRl, The Ohio State University, Advanced Computing Center for the Arts and Design, 1995. Lewis, Matthew. Texture Mapping and Image-Based Polygon Coloring in VRML Environments. OSU-ACCAD-7/95
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