Bushnell, who was sizing up potential competition, felt relieved when he learned that the pair had not unlocked any secret recipe that would allow a computer-based arcade game to thrive in the 1971 coin-op market. At over $17,000 per machine, just for parts, Galaxy Game had no ability to scale to the point where it could appear in more than one or a few locations. It would have required too much up front cost, too much maintenance, and too much time for the payout in coins to even equal the cost of the equipment involved.
When Galaxy Game made it debut at the Tresidder Memorial Union, a student community building on Stanford’s campus, the intense space simulation attracted a sizable crowd of fans, some of whom would wait hours for their chance to play. Tuck and Pitts charged 10 cents a game or a quarter for three games, with a free game going to the winner.
Galaxy Game did well enough that the duo created a second version of the game a year later (interestingly, that version could support multiple games on a single machine like Bushnell had originally planned), but the high cost of the hardware prevented the idea from going any further. “They were kind of funny guys that were technical, but not real focused on world domination,” says Bushnell. That was fine with Tuck and Pitts, who seemed content to merely dominate a single building at Stanford.
So how did both Bushnell and the Stanford duo hit upon the same idea almost simultaneously (and only six miles apart)? If history is any indication, commonly-available advances in technology tend to make certain innovations so obvious that it would be amazing if they didn’t happen. It then becomes a case of when, not if, such an invention will develop.
It’s rare that only one person invents an idea without another independently doing so shortly afterward. It had happened before with Bushnell (although he didn’t know it at the time), who wasn’t the first to invent television video games. Ralph Baer had beat him to it by a mere three years. Bushnell was, however, the first to make them work in a commercial arcade setting. But not before putting in a half-year of intense work that began when he walked into Nutting’s office on his first day as chief engineer.
Bushnell’s Rotating Rocket
With Ted Dabney’s video control board in hand, Bushnell set out to create his own interpretation of Spacewar at Nutting’s modest headquarters in Mountain View. Bushnell’s contribution to the game was somewhat analogous to those of both game designer and programmer today. Dabney had created a basic board that could put spots on a TV screen and could move them around (a system); Bushnell would design circuitry that would decide what spots to put on the screen, where, and how they would interact and respond to controls (the program).
Of course, there was no computer system or software involved. Bushnell would render his electronic game logic in hardware using medium-scale integration ICs, transistors, and diodes. It wasn’t easy.
In an era long before computer-aided design (CAD) tools existed, Bushnell spent most of his working hours at a drafting table located just outside his office door at Nutting. He utilized common engineering stencils to draw diagrams and schematics in pencil on C-size vellum. “I spent more time there than I ever did sitting in my office chair,” recalls Bushnell. He worked long hours–usually from 8 AM to midnight–in a furious push to finish his new game before a large amusement trade show in October 1971.
While Bushnell worked on the logic circuitry, Dabney visited Nutting’s offices at night to craft other aspects of the game’s hardware system, including the power supply, coin mechanism, control panel, and the sound generating circuitry. He also built the game’s prototype cabinet, a simple wooden upright-oriented box that looked similar to the Pong cabinet that he would design a year later.
Bushnell wanted his Syzygy partner to join Nutting, and Dabney still resisted. But by mid-1970, Bushnell had made such impressive progress on the game that Dabney reconsidered his position. “I was still working at Ampex,” recalls Dabney, “and I’d come in after work and see what was going on. I was blown away by what Nolan was able to accomplish. It was fantastic.” Dabney finally gave in and joined Nutting full time in the summer of that year.
According to Dabney, Bushnell’s greatest personal design triumph involved the on-screen rotation of the rocket ship, which was composed of an outline of dots with small gaps between them. “One of the hardest things to do was to get the rocket ship to actually rotate,” says Dabney. “That was a very, very difficult thing to work out.” But Bushnell did figure it out, and he says his solution is the aspect of Computer Space’s design he is most proud of.
ROM chips, the read-only integrated circuits that store digital data, were very expensive in 1971. To manufacture them inexpensively, per unit, required mass production runs to the order of thousands of chips, which was not something Nutting would have invested in for a limited-run arcade unit. So Bushnell electronically stored the shape of the rocket ship and saucer using the most basic form of read-only memory available: discrete diodes on a circuit board, which he whimsically laid out to resemble the actual shapes they represented on the screen.
In other words, if you look at the production Computer Space “memory board” (as it is labeled), you will see the outline of the on-screen rocket ship and the saucer represented as diodes soldered in place. To keep things simple and inexpensive, Bushnell wanted to have as few of these images as possible on the board.
In order to produce a fluid rotation animation, Bushnell wanted as many as 16 directions that the rocket could point. He came up with a way to do that using four images of the rocket that could be mirrored, each one being flipped once on its X-axis and Y-axis.
He then realized that an image of the rocket ship pointing straight up, when mirrored left-to-right, would result in the exact same image, so he settled on four representations of the rocket ship at different angles. “The first one was tilted just about five degrees off vertical,” recalls Bushnell, “so when I folded it, the next image was pointing 10 degrees in the other direction.” His clever scheme produced a surprisingly smooth rocket rotation for a video game created in 1971.
Bushnell also managed to implement apparently complex machine-controlled behavior of the player’s foes using a simple procedure. The two flying saucers, the target of the player’s fire, would merely detect which quadrant of the screen hosted the player’s rocket ship and it fire in that direction. “It was a total cheat,” says Bushnell of the approach, but the world’s first video game AI worked well given the technological limitations.
When he was finished, Bushnell’s logic boards appeared stunningly well-engineered to Dabney, who today raises the possibility that Bushnell received significant help with the design from his former colleagues at Ampex, especially Steve Bristow, who later joined Atari. Bushnell and Bristow both deny this. “I did none of the design work, but was involved in the construction of prototypes,” Bristow told me in a recent e-mail. For his part, Bushnell doesn’t recall Bristow being involved in the project at all: “I was the logic engineer, pure and simple.” Confusion may have arisen on Dabney’s part because Bristow engineered a later two-player version of Computer Space for Nutting.
Regarding who gets credit for what work, it is worth noting that Bushnell filed a US patent (No. 3793483) in 1972 that covered Dabney’s invention of the Computer Space video control circuitry–not the logic circuitry Bushnell created. Dabney is not listed as an inventor on the patent, which was awarded solely to Bushnell in 1974. Dabney was never aware of the patent until recently, though the fact that Bushnell didn’t include his name on the patent doesn’t keep Dabney up at night. “Nolan would never share something like that with me,” he says. “That’s just the way he did business.”
The Finishing Touches
Circuit boards, wires, and components amount to very little in the commercial arena without a pleasing exterior to attract customers; every arcade game needs a proper cabinet. Dabney’s wooden prototype Computer Space cabinet had functioned well for testing, but Nutting decided that the game needed a futuristic, attention-getting appearance to thrive as a product.
Bushnell took the task of the cabinet’s final design upon himself, sculpting a pleasing shape in gray modeling clay. He designed a sweeping, vertically-oriented enclosure with a protruding control panel assembly that coyly leaned off-center to one side. Rounded corners on nearly every part of the unit took away any intimidating edge and gave the appearance that the cabinet had been extruded as a molten dollop of technology from an alien video game gun.
Bushnell handed the sculpture off to Dabney, who shopped the model around to various cabinet makers in the area. Dabney settled on a local fiberglass manufacturer named John Hebbler that specialized in seamless hot tubs and swimming pools. The fiberglass expert did the rest. Bushnell recalls encountering the finished result sitting at Nutting Associates one day. “All of a sudden, there was a yellow one, full size, in the lab. You could have pushed me over with a feather,” says Bushnell.
While Nutting had the first Computer Space units painted in solid, primary colors, most of the later Computer Space cabinets shipped in variously-colored sparkle finishes reminiscent of a 1970s motorcycle helmet.
Bushnell’s cabinet design, which drew on Dabney’s prototype, would set the prototype for arcade video games to come, although its rough configuration wasn’t without precedent. Computer Space sported a display on top, controls in the middle, and a coin box at the bottom in an all-in-one stand-up unit similar to electromechanical arcade games such as Sega’s Missile, released only two years prior.
As a finishing touch, Bushnell’s game received a christening from Nutting’s director of sales, Dave Ralston. He settled on the name “Computer Space,” and it wasn’t hard to see why. The Computer-themed name made logical sense not only because of the pseudo-computer nature of the game, but because Nutting’s most prominent machine was called Computer Quiz. And as for the “Space” part–well, the game took place beyond the Earth’s terrestrial purview.
Near the end of the summer of 1971, Bushnell and Dabney had finished a complete, working prototype of the game, but they wondered if anyone would like it. They were about to find out.
The World Reacts
Nutting decided to place a Computer Space test unit at a Palo Alto restaurant and bar called the Dutch Goose to see how people liked it. The novel space game proved initially popular and received high praise from players at the location, but the enthusiastic response turned out to be misleading. Nutting didn’t realize it at first, but the clientele of the Dutch Goose consisted mostly of technically-adept Stanford students, which highly skewed the results.
Soon after, Bushnell and Dabney conducted another test of Computer Space in a pizza parlor with a more diverse demographic. As people tried the game, the pair listened in from a distance to gauge the public response. At first, players weren’t sure what to make of the technology or how it as supposed to work, recalls Dabney. “They’d say things like, ‘Well, you’ve got to do this. Otherwise, the rocket ship is going to get mad at you.'”
Most players found difficultly operating the machine, which combined a surprisingly realistic simulation of Newtonian mechanics with unintuitive push-button controls. The machine expected first-time video game players to understand how to pilot a rocket ship in a zero-gravity, frictionless environment in which conservation of momentum kept the ship moving unless it encountered an opposing force. If a player thrusted the rocket ship forward, it would keep moving unless he or she rotated it around 180 degrees and thrusted in the opposite direction. That’s a tricky maneuver to figure out even today, much less in 1971 with a row of four buttons–no joystick.
Even so, it’s unlikely that such a simulation would scare the average video game player now. At the time, however, very few humans on Earth had used their fingers to control an electronic image like that. With no prior exposure to video games, members of the general population had not built up the dexterity and coordination required to successfully play a multi-button interactive game. “People learned how to play video games as a group over time,” says Bushnell. “I think they could have handled it much better two or three years later.”