TITLE: What is a Tree?
AUTHOR: Eugene Wallingford
DATE: January 30, 2008 8:39 AM
I can talk about something other than science.
As I write this, I am at a talk called "What is a Tree?",
by computational artist
In it, Greenberg is telling his story of going from art
to math -- and computation -- and back.
Greenberg started as a traditional artist, based in drawing
and focused in painting. He earned his degrees in Visual
Art, from Cornell and Penn. His training was traditional,
too -- no computation, no math. He was going to paint.
In his earliest work, Greenberg was caught up in perception.
He found that he could experiment only with the motif in
front of him. Over time he evolved from more realistic
natural images to images that were more "synthetic", more
plastic. His work came to be about shape and color. And
Alas, he wasn't selling anything. Like all of us, he needed
to make some money. His uncle told him to "look into
computers -- they are the future". (This is 1993 or so...)
Greenberg could not have been less interested. Working with
computers seemed like a waste of time. But he got a computer,
some software, and some books, and he played. In spite of
himself, he loved it. He was fascinated.
Soon he got paying gigs at places like Conde Nast. He was
making good money doing computer graphics for marketing and
publishing folks. At the time, he said, people doing
computer graphics were like mad scientists, conjuring
works with mystical incantations. He and his buddies found
work as a hired guns for older graphic artists who had no
computer skills. They would stand over his should, point
at the screen, and say in rapid-fire style, "Do this, do
this, do this." "We did, and then they paid us."
All the while, Greenberg was still doing his "serious work"
-- painting -- on side.
But he got good at this computer stuff. He liked it. And
yet he felt guilty. His artist friends were "pure", and
he felt like a sell-out. Even still, he felt an urge to
"put it all together", to understand what this computer
stuff really meant to his art. He decided to sell out all
the way: to go to NYC and sell these marketable skills for
big money. The time was right, and the money was good.
It didn't work. Going to an office to produce commercial
art for hire changed him, and his wife notice. Greenberg
sees nothing wrong with this kind of work; it just wasn't
for him. Still, he liked at least one thing about doing
art in the corporate style: collaboration. He was able
to work with designers, writers, marketing folks. Serious
painters don't collaborate, because they are doing their
The more he work with computers in the creative process,
the more he began to feel as if using tools like Photoshop
and LightWave was cheating. They provide an experience
that is too "mediated". With any activity, as you get
better you "let the chaos guide you", but these tools --
their smoothness, their engineered perfection, their Undo
buttons -- were too neat. Artists need fuzziness. He
wanted to get his hands dirty. Like painting.
So Greenberg decided to get under the hood of Photoshop.
He started going deeper. His artist friends thought he
was doing the devil's work. But he was doing cool stuff.
Oftentimes, he felt that the odd things generated by his
computer programs were more interesting than his painting!
He went deeper with the mathematics, playing with formulas,
simulating physics. He began to
substitute formulas inside formulas
inside formulas. He -- his programs -- produced "sketches".
At some point, he came across
"an open source programming language and environment for
people who want to program images, animation, and interactions".
This is a domain-specific language for artists, implemented
as an IDE for Java. It grew out of work done by John Maeda's
group at the MIT Media Lab. These days he programs in
ActionScript, Java, Flash, and Processing, and promotes
Processing as perhaps the best way for computer-wary artists
to get started computationally.
With his biographical sketch done, he moved on to the art
that inspired his talk's title. He showed a series of
programs that demonstrated his algorithmic approach to
creativity. His example was a tree, which was a double
entendré for his past as a painter of natural
scenes and also for his embrace of
He started with the concept of a tree in a simple line
drawing. Then he added variation: different angles,
different branching factors. These created asymmetry
in the image. Then he added more variation: different
scales, different densities. Then he added more variation:
different line thickness, "foliage" at the end of the
smallest branches. With randomness elements in the
program, he gets different outputs each time he runs the
code. He added still more variation: color, space,
dimension, .... He can keep going along as many different
conceptual dimensions as he likes to create art. He can
strive for verisimilitude, representation, abstraction,
... any artistic goal he might seek with a brush and
Greenberg's artistic medium is code. He writes some code.
He runs it. He change some things, and runs it again.
This process is interactive with the medium. He evolves
not a specific work of art, but an algorithm that can generate
an infinite number of works.
I would claim that in a very important sense his work is
the algorithm. For most artists, the art is in the
physical work they produce. For Greenberg, there is a
level of indirection -- which is, interestingly, one of
the most fundamental concepts of computer science. For
me, perhaps the algorithm is the artistic work! Greenberg's
program is functional, not representational, and what
people want to see is the art his programs produce. But
code can be beautiful,