Project Number: 48-MH-0223 FRACTALS AND ART An Interactive Qualifying Project Report Submitted to the Faculty of the WORCESTER POLYTECHNIC INSTITUTE in partial fulfillment of the requirements for the Degree of Bachelor of Science by Steven J. Conte and John F. Waymouth IV Date: April 29, 2003 Approved: 1. Fractals 2. Art Professor Mayer Humi, Advisor 3. Computer Art Abstract Fractalsaremathematicallydefinedobjectswithself-similardetail on every level of magnification. In the past, scientists have studied their mathematical properties by rendering them on computers. Re- cently, artists have discovered the possibilities of rendering fractals in beautiful ways in order to create works of art. This project pro- vides some background on several kinds of fractals, explains how they are rendered, and shows that fractal art is a newly emerging artistic paradigm. 1 Contents 1 Executive Summary 5 2 Introduction 6 2.1 Fractals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 3 Are Fractals Art? 9 4 The Mandelbrot and Julia Sets 12 4.1 The Mandelbrot Set . . . . . . . . . . . . . . . . . . . . . . . 12 4.1.1 Definition . . . . . . . . . . . . . . . . . . . . . . . . . 12 4.1.2 Mandelbrot Image Generation Algorithm . . . . . . . . 13 4.1.3 Adding Color . . . . . . . . . . . . . . . . . . . . . . . 15 4.1.4 Other Rendering Methods . . . . . . . . . . . . . . . . 18 4.2 The Julia Set . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 4.3 Self-Similarity of the Mandelbrot and Julia Sets . . . . . . . . 19 4.4 Higher Exponents . . . . . . . . . . . . . . . . . . . . . . . . . 20 4.5 Beauty and Art in the Mandelbrot and Julia Sets . . . . . . . 21 4.5.1 Finding interesting fractal images . . . . . . . . . . . . 22 4.5.2 Deep zooming . . . . . . . . . . . . . . . . . . . . . . . 23 4.5.3 Coloring techniques . . . . . . . . . . . . . . . . . . . . 25 4.5.4 Layering . . . . . . . . . . . . . . . . . . . . . . . . . . 26 5 Iterated Function Systems 28 5.1 Affine Transformations . . . . . . . . . . . . . . . . . . . . . . 28 5.2 Contraction Mappings . . . . . . . . . . . . . . . . . . . . . . 29 5.3 Example: Sierpinski Gasket . . . . . . . . . . . . . . . . . . . 29 5.4 The Non-Deterministic Rendering Algorithm . . . . . . . . . . 31 5.5 Fractint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 5.6 FDESIGN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 6 L-Systems 36 6.1 Origin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 6.2 Lexical Substitution . . . . . . . . . . . . . . . . . . . . . . . 37 6.3 Graphical Interpretation . . . . . . . . . . . . . . . . . . . . . 37 6.3.1 Branching . . . . . . . . . . . . . . . . . . . . . . . . . 39 6.4 Fractint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 2 7 Fractal Dimension 45 7.1 The Hausdorff Dimension . . . . . . . . . . . . . . . . . . . . 45 7.1.1 The Koch Curve . . . . . . . . . . . . . . . . . . . . . 47 7.2 Box Dimension . . . . . . . . . . . . . . . . . . . . . . . . . . 47 7.2.1 Example: The Sierpinski Gasket . . . . . . . . . . . . . 48 7.2.2 Example: The Koch Curve . . . . . . . . . . . . . . . . 50 8 Jackson Pollock’s Fractal Paintings 52 9 Fractal Music 55 9.1 Example 1: Random note generator . . . . . . . . . . . . . . . 56 9.2 Example 2: Random multiple note generator . . . . . . . . . . 57 9.3 Example 3: Random chord generator . . . . . . . . . . . . . . 57 9.4 Adding human talent . . . . . . . . . . . . . . . . . . . . . . . 58 10 Art as a Reflection of Society 60 10.1 Art as a Reflection of the Mind . . . . . . . . . . . . . . . . . 61 10.2 Motivation for Art . . . . . . . . . . . . . . . . . . . . . . . . 62 11 Making Art More Accessible 65 11.1 The Art Question . . . . . . . . . . . . . . . . . . . . . . . . . 65 11.2 A New Artistic Paradigm . . . . . . . . . . . . . . . . . . . . 67 12 Psychology of Fractal Art 68 12.1 Vassallo’s art . . . . . . . . . . . . . . . . . . . . . . . . . . . 70 12.2 The John IFS . . . . . . . . . . . . . . . . . . . . . . . . . . . 72 12.3 Janet Parke’s “Then I Saw a New Heaven” . . . . . . . . . . . 73 12.4 Dots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 13 Conclusions 79 A Source Code Listings 81 A.1 Mandelbrot and Julia Set Generator . . . . . . . . . . . . . . 81 A.2 Box-Counting Dimension Calculator . . . . . . . . . . . . . . . 84 A.3 Fractal Music Generator . . . . . . . . . . . . . . . . . . . . . 85 B Programs Used 92 B.1 Fractint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92 B.2 XaoS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93 3 B.3 FDESIGN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95 B.4 Ultra Fractal . . . . . . . . . . . . . . . . . . . . . . . . . . . 95 C Fractal Poster 97 D Supplementary CD 99 E References and Further Reading 100 E.1 Are Fractals Art? . . . . . . . . . . . . . . . . . . . . . . . . . 100 E.2 The Mandelbrot and Julia Sets . . . . . . . . . . . . . . . . . 100 E.3 Iterated Function Systems . . . . . . . . . . . . . . . . . . . . 100 E.4 L-Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101 E.5 Fractal Dimension . . . . . . . . . . . . . . . . . . . . . . . . . 101 E.6 Jackson Pollock’s Fractal Paintings . . . . . . . . . . . . . . . 101 E.7 Fractal Music . . . . . . . . . . . . . . . . . . . . . . . . . . . 102 E.8 Art and Society . . . . . . . . . . . . . . . . . . . . . . . . . . 102 E.9 Making Art More Accessible . . . . . . . . . . . . . . . . . . . 103 E.10 Fractal Art Psychology . . . . . . . . . . . . . . . . . . . . . . 103 4 1 Executive Summary This Interactive Qualifying Project explores the overlap between the sub- jects of fractals and art. We sought to find out how mathematics could be involved in the process of creating art and to explore the humanistic side of fractals. To do this, we explore several different kinds of fractals, explain their mathematical definition, and show how they could be used to generate aesthetically beautiful images. Then we explore the sociological side of frac- tal art, and we analyze the psychology behind the aesthetic beauty found in several pieces of fractal art. This report begins with a brief introduction to the topic of fractals and then addresses the question of whether fractals can be considered a form of art. At this point, we establish the goal for this project: to prove that fractal art is a new form of art. Proceeding from this point, we give a general mathematical background of some of the mathematical details of several kinds of fractals, including the Mandelbrot and Julia sets, iterated function systems, and L-Systems. Then we describe the concept of fractal dimension, and demonstrate how to calculate the dimension of several example fractals. Using this infromation, we explore how the concept of fractal dimension can be applied to works of art. From this point the report delves into more humanistic issues. It is in- teresting to generate classic fractals such as the Koch curve and Sierpinski gasket, but how can we use fractals to create truly beautiful art? We show how fractals can be used to generate music, and we discuss the artistic value of such music. Next, we explore the relationship between art and society. Theories of how society is reflected in art are discussed, and we try to answer the question,“What does fractal art say about our society?” Finally, we ap- ply existing psychological studies about the perception of art to a few pieces of work by fractal artists, to show that many of the same qualities found in traditional art can also be found in fractal art. 5 2 Introduction The field of mathematics has seen many recent discoveries related to frac- tals. Fractals hold many secrets that mathematicians are only beginning to unlock. From the intricate and colorful Mandelbrot set to the infinitely repeating pattern of the Koch curve, fractals hold the interest of many. Re- cent discoveries have found fractals and similar formations in many areas of research such as physics and geometry. Other links can be found between fractals and natural formations such as mountain ranges. Fractals can even be found in works of art, where a painting has more detail visible when you examine its edges arbitrarily closely. This Interactive Qualifying Project (IQP) focuses on the artistic possibil- ities of fractals. It is the goal of this IQP to explore the applications of the growing field of fractals to the arts. We will give a general introduction to fractals, and then show how these ideas relate to various areas of art. In this way, we intend to demonstrate that, along with having intriguing scientific ramifications, fractals have a very important humanistic side. This, we feel, relates science and sociology, which is the purpose of an IQP. The authors hope to broaden their own knowledge of fractals as well. This project provides two interesting opportunities: we not only will explore what mathematically defines a fractal and what mathematical properties they have, but we will also see how fractal images can be considered works of art. Science thrives on the benefits it gives to average people. There would be no purpose to scientific discovery if it did not bring improvement to the lives of many people. Medicine is an obvious example: medical discoveries lead directly to improving the health of patients. Fractals can also provide a ben- efit in that even purely mathematical fractal images such as the Mandelbrot and Julia sets are strikingly beautiful. The authors hope to broaden the impact of their existing scientific knowl- edge by seeing how it can positively affect peoples’ lives. Instead of studying only the pure mathematics of fractals, we will forge a link between mathe- matics and beauty. It is our hope that we can gain some experience with what beauty itself is. In this way, our future scientific efforts will be im- proved because we will be more attuned to how our efforts will be viewed by an average person. And as was outlined above, this is arguably a very important consideration when exploring science. One can find many examples of beauty in fractals. It would not be effec- 6 tive to try to cover all of the many types of fractals at once, and it is beyond the scope of an IQP. However, we feel that we can gain some of the insight described above by focusing on a few links between fractals and art. By exploring some examples, we hope to show how fractals and art are deeply related as a whole. 2.1 Fractals The term “fractal” encompasses a somewhat loosely defined type of mathe- matical object. Traditionally, fractals are defined as objects exhibiting self- similarity; that is, objects containing parts that look like the whole when magnified. Objects like the Koch Curve and Iterated Function Systems, which will be explored later, are self-similar objects. When using this defi- nition of “fractal”, it is implied that these objects must have new detail on every scale of magnification. In fact, fractals are commonly described using just this last criterion: that they have fine detail of a similar structure at every scale of magnification. This is the definition used for this IQP, which allows us to explore such objects as the Mandelbrot and Julia sets, which do not exhibit true self-similarity. The fine detail common to fractal images is what helps to make them beautiful and fascinating to behold. Fractal images tend to be wildly chaotic, with new and interesting formations that draw the eye. They usually have vivid color and often exhibit self-similarity, or at least some general form of self-mimicry, at many levels. The eye is often drawn to explore a tiny detail, which, on closer inspection, is very similar to the image as a whole. This plays on the natural human instinct to correlate and explore similar visual stimuli. It is more interesting, for artistic purposes, to concentrate on the rep- resentation of fractals in a computer graphics environment. Fractals them- selves are infinitely detailed mathematical constructs, so it is not possible for humans to visually and aesthetically experience a fractal object. It is the rendering process that brings some sense of order out of chaos: it gives us a way to visualize a fractal. It is important to understand that the images produced by processes described in this IQP are not the fractals themselves; they are just a graphical approximation of the fractal object. As we will demonstrate, the rendering process plays just as important a role in creating an aesthetically pleasing image as the fractal formula itself. To represent a fractal graphically, it is necessary to make many choices, 7 such as color, size of image, parameters, rendering effects, and many other possibilities. Choosing a good rendering method can produce an image of startling depth and beauty, while choosing a poor rendering method can createanimagethatseemslikearandomcollectionofdifferentlycoloreddots. This project will demonstrate several popular fractal rendering methods and explore their aesthetic appeal. 8 3 Are Fractals Art? Beforeweexploredifferentkindsoffractalart, itisimportanttoconsiderthis question: can fractals, in fact, be considered a form of art? Certainly one can see,byflippingthroughthediagramslaterinthisreport,thatthereareplenty of examples of intriguing and beautiful fractals. But the question remains, can we place our work in the same field as da Vinci and Michaelangelo? Can the process of manipulating mathematical formulas be likened to a process of artistic creation? At the outset, some people will argue that the answer is no. They claim that, because fractals have mathematics as their basis, there is no chance for a person to introduce meaning and intrigue. Mathematics is, after all, a dry field of unwavering truths and equations; numbers don’t express emotion. Others might point out that fractal images exist only as the creation of a computer. Computers follow specific instructions and cannot think for them- selves or experience emotion. Or perhaps opponents will point out the fact that the fractal image was “always there”, just waiting for the mathemati- cian to stumble across it. Finally, perhaps conceding that there are infinite possible images to be found in a given fractal, opponents have argued that the “artist” is merely punching in random numbers to create his images. Thepurposeofthisprojectistoshow, byexampleandbydiscussion, that fractal imagery is an art form in and of itself. The number of possible images in each fractal is infinite, and not every one of these is even remotely aesthet- ically pleasing. But some fractal images are strikingly beautiful. They have infinite detail that can always yield new shapes at closer inspection. Their self-similarity tantalizes our natural need to make associations between con- cepts in our minds. They can be intriguing, and undeniably beautiful...but are they art? What is art, anyway? Authors have written long philosophical volumes attempting to tackle that question. Indeed, the question is beyond the scope of this project. We will have to settle with a working definition, and use this to give the reader a sense that there is art in fractals. Weknowthatcertainworksbythegreatartistsstrikeusasbeautiful. For somereason,apicturewillintrigueorfascinateus. Otherworkscommunicate emotions to us, or try to make a point. Some works, like the drawings of M. C. Escher, try to catch our interest with a visual riddle. All of these qualities can also be found in fractal art. But what about the idea of artistic process? Fractals are static images, 9