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THE SCULPTURES I have been making are ghosts: they exist only as computer
data, and not in physical form. Artists have made sculptures from many different
materials – marble, steel, bricks and wood – in the workshop or studio.
In contrast, I create my sculptures, or forms, in a ‘virtual’ space viewed
through the porthole of a computer screen. Using the computer, I can rotate
and view the forms from any point, and can simulate visual attributes such
as texture, lighting and surface qualities using techniques that give photographic
realism.

The result is a highly realistic representation of a sculpture that
does not exist. The three-dimensional realism is enhanced by using stereo
projection and animation. The fact that you cannot touch the sculpture,
and that it exists only in virtual space, adds to the mystery of the work
of art. The true significance is not the irony of being unable to touch
my sculpture, but that by working in computer space I can create highly
complex forms that would be impossible in traditional sculpture. This is
because there is no gravity or material resistance. This allows me to explore
and invent forms which had previously been outside my imagination. These
forms I call ‘computer sculptures’.

There is another aspect of the work that is perhaps more interesting.
That is the systematic approach and rules devised with my colleague Stephen
Todd at IBM to generate the forms. These rules are called ‘form evolution’.
Using these rules, there appears to be no limit to the number of different
forms you can produce, from shells to eggs, antlers, slugs and sea urchins.
Although we are creating forms that appear imaginary, poetic or even ‘romantic’,
we are actually using a structured and systematic approach.

I experimented with a system for creating complex sculptures before
using computer graphics. At the Royal College of Art, I developed a way
of designing sculptures called the evolutionary tree. This approach takes
a series of simple operations and carries them out on basic shapes to create
complex forms. Using this method, I drew by hand a chart of evolutions,
measuring 10 metres long by 2 metres high. It became obvious that my aim
of exploring complex forms could well be helped by computer.

Meanwhile, people at the IBM UK Scientific Centre in Winchester were
looking at ways of visualising scientific data, and had developed a variety
of systems. These included a database graphics system for data exploration,
and a modeller called the Winchester Solid Modeller (WINSOM) – developed
by Peter Quarendon and others at IBM for data visualisation. WINSOM works
with a programming tool called the Extensible Solid Model Editor (ESME),
which was written by Stephen Todd for experimenting with different picture
styles.

In 1987, the Scientific Centre commissioned me to produce a series of
computer sculptures using the WINSOM and ESME computer programs. The results
encouraged longer collaboration, aimed at using the computer for faster
form exploration and generation, to widen a sculptor’s creative scope. It
became apparent that this work was also interesting to designers and architects
who are similarly involved with problems of modelling complex forms.

The collaboration has two aspects. Using simple programmed operations
(written in the ESME language) helps me explore complex forms. The photo-realistic
techniques of WINSOM allows me to realise and communicate these forms.

The WINSOM and ESME models are based on the concept of ‘set-theoretic’
modelling. This can generate solid objects from basic building blocks such
as spheres, which are combined by set-theory operations such as union and
difference. Engineers often use this type of modelling for a variety of
applications.

ESME is a conventional programming language with additional functions
that handle geometry and solid modelling. Two ESME functions provide the
operations used to generate most of my complex forms.

The first of these is the ‘horn’ function, which takes a form and transforms
it many times, creating many different shapes. The variety depends on the
original form, and on the instructions defining a horn, such as bend, scale,
twist, grow and stack. These terms are words that any sculptor would use
when talking to a technician in a traditional studio. The second function
is ‘branch’. This takes a form and produces many copies of it, radiating
from a central point.

Combining these simple functions with the power of set-theoretic modelling
allows me to construct a huge range of forms. There are an infinite number
of sculptures that I could create, but at any given moment the functions
and parameters of the program constrain me to a limited number of choices.
This has proved a very good mixture to encourage creative output, and has
focused my ideas.

None of the forms I have generated at the IBM Scientific Centre has
ever existed as a ‘real’ object. They appear as high-resolution screen images
or photographs, or as animations on videotape. As a form develops, I use
a variety of ‘realisations’. The simplest realisation is a sketch, or wireframe
which I can generate very quickly, and can rotate on the screen at will.
I use this to check the basic form and to choose interesting views. Many
forms never progress beyond this stage. Next, using WINSOM, I fill in and
colour the form in three dimensions, in a low-resolution version, to check
that there are no features hidden in a way that was not obvious from the
wire frame. Finally, WINSOM generates a full high-resolution photo-realistic
image.

To obtain the image, I can use a whole battery of special effects. These
include three-dimensional texturing, shadows, colour and surface qualities.
To use these effects, I set various parameters: these determine the lighting,
or define a style of texturing using fractal techniques, or describe a special
colour or particular ‘bumpy’ surface qualities.

When using these photo-realistic techniques, my intention is to give
the forms a dream-like quality. My forms float in a kind of twilight world
halfway between the real and the imaginary. And as in a dream, they are
lit with a strange eerie glow and have a curious clarity.

We can make the sculptures appear even more three-dimensional using
stereoscopic projection. It is possible to use stereo pairs, with two projectors
and polarising filters. This requires a special screen. Alternatively, a
red and a green image are combined on a single slide. This requires only
one projector, but loses the colour of the image. In either case, the viewer
must wear the appropriate spectacles. Texture is particularly important
for stereo viewing, because it allows greater perception of depth, and enhances
the three-dimensional quality.

Animations are much better at giving a viewer a full appreciation of
the form of an object. The simplest type of animation rotates the form in
front of the viewer so that you can see all round it. More complex animations
lead the viewer round, or even through, a form. The same ESME program that
generates the form creates the viewing path. Finally, the power of animation
allows the form itself to grow and distort.

The combination of photo-realism and computer graphics is popular with
the general public and lends itself to mass reproduction and television
broadcasts. As soon as sculptures become ‘data’ then the artwork need not
reside in the art gallery, because the artist can transmit it into the viewer’s
living-room.

In future, we expect to allow users to be more directly involved in
designing the forms. The mathematics of form-generation functions will,
however, still constrain the interaction with the user. There will not be
the freedom associated with ‘paintbox’ systems, such as those used by television
companies to create graphics for maps, diagrams and title sequences. But
we will marry form-generation techniques with my original concept of the
evolutionary tree, to give users a new type of interface. In this way, users
will have a quick and easy way to generate complex forms.

The ‘form evolution’ approach has allowed me to create shapes that had
previously been beyond my imagination, and to present the results to the
viewer. As holography improves, it will be possible to project a full-size
sculpture into the viewer’s living room: the ghosts of sculptures will truly
appear. Perhaps we will no longer need to have sculptures in physical form
at all.

The exhibition The Conquest of Form, computer art by William Latham,
produced at the IBM UK Scientific Centre, is currently touring Britain.
It can be seen at the Natural History Museum in London from June 1990 for
3 months.