Plotter Pioneers

From monastery to plotter

Roman Verostko (1929–2024) was born Joseph Verostko in Tarrs, Pennsylvania, a coal town in the western part of the state. On his twenty-first birthday, in 1950, he entered monastic life at Saint Vincent Archabbey and took the name Roman. He was ordained a Catholic priest in 1959. According to his professional record he earned an M.F.A. from Pratt Institute in 1961 and studied in Paris, including at Stanley William Hayter's Atelier 17 and the École du Louvre. In 1968 he left religious life, married Alice Wagstaff, moved to Minneapolis, and joined the faculty of the Minneapolis College of Art and Design, where he taught until 1994. By his own account he was introduced to programming at the Control Data Institute in 1970, and he turned his studio into what he called an electronic scriptorium.

Hodos and the genotype essay

Verostko named his software Hodos, from the Greek word for "path" or "road," the same root that gives us "method." The program's algorithms describe paths, and following those paths is how a drawing gets made. He set out his theory in an essay, "Epigenetic Painting: Software as Genotype," presented at FISEA'88 in Utrecht in 1988 and published in Leonardo, volume 23, number 1, in 1990.

The essay borrows from biology:

the software, Hodos, may be viewed as a genotype (gene) since it is the code for 'how to make the work'

Any single finished drawing is one expression of that code, its phenotype:

The software may be viewed as 'genotype', the painting as 'phenotype', and the process as epigenesis.

He called software and machine together a personal expert system:

By personal expert system I mean the software art and the hardware capable of processing unique art concepts of a particular artist.

He did not claim the framework as his alone. In the same essay he named Jean-Pierre Hébert, Harold Cohen, and Manfred Mohr as colleagues who also use original coded procedures to generate artistic form, work whose "algorithms may also be compared to genotype." That put his practice next to Cohen's rule-based AARON system and Mohr's coded geometry.

The brush-adapted plotter

Verostko's machine was a Houston Instruments DMP-52, not an HP. It was a pen plotter with fourteen pen stalls in two banks of seven, driven by his own BASIC programs issuing DMPL, the Houston Instruments plotter-control language. With fourteen stalls he could use many inks in a single run.

In 1987 he adapted the drawing arm to hold oriental brushes in place of technical pens, and that change opened the Pathway Series of the same year. He treated the arm as an extension of his own hand, and the strokes taper and swell the way a loaded brush does. In the tool, the pen sets stand in for the fourteen stalls and the brush-width control for the adapted arm.

What a pen plotter is

A pen plotter was built for engineering and architectural drafting. It moves a real pen across paper in continuous strokes rather than laying down a raster of dots, and it often holds several pens in a carousel so it can change color or line weight in the middle of a drawing. Early desktop models, such as the six-pen HP 7475A, rotated their pens on a small Geneva-drive carousel and took their commands in HP-GL.

So plotter output looks different from print. Every mark is one unbroken ink stroke with a real start, path, and end. The pen presses and lifts, and ink pools slightly at the turns. The tool imitates this with clean vector paths and a faint wobble.

The four presets

The presets in the tool are based on four of Verostko's series.

The Cyberflower series took its name from a colleague's exclamation, "Computer flowers!", on first seeing the plots. Each work begins from a single set of randomly chosen coordinates and generates curvilinear lines from that seed. Verostko keeps artistic control by narrowing or widening the parameter ranges the machine may choose within. A multi-pen plotter then lays down thousands of individual lines in pigmented inks on rag paper. The Victoria and Albert Museum, which holds a 2008 example, describes the tension in his practice as one between "random selection and rational control."

In the Pathway Series (1987), a single algorithm dictated the shape, distribution, and color of every line on the page. Diamond Lake Apocalypse paired symmetrical brushstrokes whose shared control points governed every pen stroke in the work; he drew it in the scriptorium overlooking Diamond Lake in Minneapolis. The Manchester Illuminated Universal Turing Machine, begun with work #1 in 1998 for the fiftieth anniversary of the Manchester "Baby" computer of 1948, sets Turing's Universal Turing Machine algorithm as binary text on one page, facing a generated illumination on the other, like an open illuminated manuscript. It is drawn on hot-pressed Arches paper, with burnished gold leaf marking the start and end of the code.

The Algorists (1995)

In August 1995, after a SIGGRAPH panel in Los Angeles titled "Artists and Algorithms," Verostko, Jean-Pierre Hébert, the mathematician-sculptor Helaman Ferguson, and the graphics researcher Ken Musgrave founded a group they called the Algorists. Hébert proposed the term, reasoning that algorists ought to be defined with an algorithm, and wrote the identifying pseudocode. Verostko reproduced it on his own site "formatted precisely as received," so it is set here as archived, including elseif as one word:

if (creation && object of art && algorithm && one's own algorithm)
{ include * an algorist * }
elseif (!creation || !object of art || !algorithm || !one's own algorithm)
{ exclude * not an algorist * }

To count, an artist has to write the algorithm, not just use a computer. Verostko later gave Mohr as an example:

An artist like Manfred Mohr writes all his own software, and the code itself embodies a generative concept that is unique. That is an Algorist.

Verostko and later historians cite Mohr's coded, generative practice as an example of what "algorist" means. He was not one of the group's four founders, and no statement from Mohr himself embracing or rejecting the term has been located. He appears here as an example named by others.

Before and after Verostko

Verostko began with the same category of machine, the pen plotter, that Georg Nees and Frieder Nake used in Stuttgart, where Nees's 1965 show is widely called the first exhibition of computer art, and that Vera Molnár and Manfred Mohr reached in Paris in the years around 1970. He named Cohen's AARON and Mohr's coded geometry as kindred personal expert systems. His insistence that an algorist writes the algorithm, rather than just using a computer, is close to what Sol LeWitt did when he gave written instructions to human drafters.

Hobbyists who draw today with AxiDraws and fibre-tip pens work with the same mechanics he used on adapted drafting machines: continuous ink strokes, several pens, several passes, and a pen change as a color decision.

Late in life he said:

If I had known I was going to live this long, I would have continued with programming languages!

He died at his Minneapolis home on 1 June 2024, at the age of ninety-four.