Pac-Man | Code Like It's 198x

When Namco’s American partner first saw Pac-Man, its boss wanted nothing to do with it. “It’s silly,” said Robert Mullane, the president of Bally, which owned Midway. “Anyway, who plays a maze game?” Midway’s managers overruled him. Two years later there were 100,000 Pac-Man machines in American arcades, a hit record about the game had sold a million copies, and Midway was telling reporters that nearly 100 companies were making 500 different Pac-Man products.

The game was the work of Toru Iwatani at Namco. It had no shooting and one joystick, a hero who was little more than a yellow circle with a mouth, and four ghosts that did not all chase him the same way.

Explore the Pac-Man study for a closer look at routes, power pellets, ghost decisions, the people behind the cabinet and the game’s later life.

Fast facts

Designer: Toru Iwatani, at Namco.
Released: 1980 in Japan, as Puck-Man; later in 1980 in America, as Pac-Man, built under licence by Midway.
Controls: one joystick, no buttons.
Maze: 240 dots at 10 points each, and four power pills.
Ghosts: Blinky, Pinky, Inky and Clyde.
American machines: 100,000 by August 1982, at about $2,500 each.

An eating game

Iwatani joined Namco in 1977, shortly after leaving college, and his first games were what Edge called “video pinball games”. In 1979 he set out to make a game that women would play. He told Edge in 2010 that arcade games of the time “were violent and focused on the male player, so the game centres became places frequented mainly by men”. “When I imagined what women enjoy,” he said, “the image of them eating cakes and desserts came to mind so I used ‘eating’ as a keyword.” The shape of the hero came at lunch: “As I was eating pizza, I took a slice away and looked at what was left.”

He kept the character as plain as he could. “I designed Pac-Man to be the simplest character possible, without any features such as eyes or limbs,” he told Edge in 1998. The more human-looking Pac-Man of the American artwork was added later. A maze gave the eating a shape (“Just moving around an open field would be too much freedom and no fun”), and he made the whole game work from one joystick, so that “even girls who hadn’t played many arcade games could play and enjoy” it.

Namco’s own staff told the story a little differently in 1982. Hide Nakajima, of Namco’s American company, told Video Games that “people were fed up with space games. So we started to dream up games that would make them laugh.” In Japanese, he explained, puck is the sound of eating something good: “Puck, puck, puck instead of blam, blam, blam.” The same article pointed out that women in Japan already played every kind of game, and that American arcades were the ones that changed. It called Pac-Man “the game that dragged women out of the video closet and into the arcades”.

Puck-Man becomes Pac-Man

Namco offered the game to Midway, which already built Galaxian under licence, early in 1980. The title had to change first. “They didn’t like how it rhymed with your very popular expletive,” Nakajima said, “so we changed it to Pac.”

The American trade was not impressed either. At the operators’ show in Chicago in November 1980, most of the hit games were still space games. Edge reported in 2010 that the trade expected Namco’s other new game, the car-chase maze Rally-X, to be the success. Midway’s marketing director, Stan Jarocki, remembered that “people thought that the cute-factor was going to nail us.”

Playing it

The rules fit in a paragraph. Pac-Man has to clear a maze of 240 dots while four ghosts hunt him. One touch and he folds up and disappears. In each corner of the maze is a power pill; eat one and the ghosts turn blue and run, and for a few seconds Pac-Man can eat them and send their eyes floating back to the pen in the middle. Twice in each maze a bonus appears below the pen, starting with cherries and working up to keys, and it is worth more the further the player gets. Clear the maze and it refills, faster. After some mazes the game stops for a short cartoon, which Iwatani said gave players “a chance to catch their breath” and a reason to play on.

Iwatani thought the ghosts were as important as the hero. “All of the ghosts have different AI algorithms that reflect their comical personalities,” he told Edge. “It’s sort of like asking whether Tom or Jerry is the star of the Tom and Jerry cartoons.” He had wanted, he once said, “each ghostly enemy to have a specific character and its own particular movements, so they weren’t all just chasing after Pac-Man in single file”.

How the ghosts chase

Namco did not publish how the ghosts work, but players and programmers have since worked out the rules from the arcade program. The fullest public account is Jamey Pittman’s The Pac-Man Dossier. The ghosts do not think or plan. At each junction a ghost picks the turn that brings it nearest to a target square, and the four ghosts pick their target squares differently:

Blinky (red) aims at the square Pac-Man is on.
Pinky (pink) aims four squares ahead of Pac-Man, in the direction he is facing. That is why Pinky seems to cut him off.
Inky (cyan) uses Blinky’s position too. It takes the square two ahead of Pac-Man and doubles the line from Blinky to that square. When Blinky is close behind Pac-Man, Inky ends up close to him as well; when Blinky is far away, Inky aims well away from him.
Clyde (orange) chases Pac-Man directly while he is eight squares away or more. Any closer and he heads for his home corner, so he seems to lose his nerve.

The ghosts do not chase all the time. Four times in each level they break off and head for their own corners of the maze, then turn back on the player. Wireframe credits the idea to Iwatani, who realised the game “would be far more compelling if the ghosts attacked in waves”.

There is a mistake in the code as well. When Pac-Man faces up, the calculation of the squares “ahead” of him also moves the point the same distance to the left. Pinky and Inky aim at the wrong place, and players have used the gap for decades.

What it earned

Video Games summed up the arcade figures in August 1982. With 100,000 machines in American arcades, Pac-Man had overtaken Space Invaders and Asteroids “to become the acknowledged King of the Arcades”. A machine cost an operator about $2,500. Midway, the magazine said, owed “approximately $200 million” to Pac-Man sales. By December 1982 Midway had built 190,000 Pac-Man and Ms. Pac-Man machines between them. Edge, looking back in 1998, put Pac-Man’s sales at more than 350,000 machines and called it “by far the most successful arcade machine of all time”; it did not say where the figure came from, and neither Namco nor Midway published a worldwide total.

The character sold as well as the game. In 1982 Video Games listed Pac-Man pyjamas, sheets, soap, lunch boxes, watches, telephones and shoes “with matching laces”. Jarocki said nearly 100 companies held licences for some 500 products, and Midway expected between 8 and 10 million dollars from licensing in 1981 alone. Buckner & Garcia’s single “Pac-Man Fever” reached the Top Ten and, by the summer of 1982, had sold more than a million copies. David Sheff adds that the character was on the covers of Time and Mad, and had its own Saturday-morning cartoon.

Ms. Pac-Man

The sequel came from America, not Japan. Its code began as Crazy Otto, a modification of Pac-Man written by an independent company, General Computer Corporation. Midway agreed a deal with General Computer in October 1981 and turned Crazy Otto into Ms. Pac-Man. Video Games described what had changed: Ms. Pac-Man wore a bow and lipstick, the fruit moved around the maze, and there were two more escape tunnels. The cartoons between levels now told a story, from the day Pac-Man and Ms. Pac-Man met to the arrival of a baby. Midway expected to ship 94,000 Ms. Pac-Man machines in 1982.

The last level

The arcade game has no ending, but it does have a last level. The program keeps the level number in a single byte, which can count only to 255. On level 256 the routine that draws the row of bonus fruit at the bottom of the screen runs past its end, and fills the right half of the maze with garbled characters. The game counts a level as finished after 244 dots and pills, and only 123 are left to eat, so the level cannot be cleared. The highest possible score, for catching all four ghosts after every power pill, eating every fruit and never losing a life all the way to level 256, is 3,333,360.

At home

Atari held the home rights. Its 2600 cartridge, launched with a “National Pac-Man Day” in April 1982, disappointed players who knew the arcade game. Its ghosts flickered because the console could draw only one of them in each frame, and the maze ran sideways. It still sold in the millions. Video Games Player listed it in September 1983 as the biggest hit of 1982, at 7 million cartridges, and later accounts say Atari made about 12 million. That entry has the full story.

Electronic Fun found Atari’s version for its own 400 and 800 computers “very close to the arcade version”, and Atari’s Atarisoft label sold Pac-Man for other companies’ machines, among them the Commodore 64, VIC-20, Apple II and IBM PC. Namco published Pac-Man itself for the Famicom, where Edge counted it among Namco’s first big sellers. In America, Tengen, the home label of Atari Games, announced it for the NES in June 1988.

Sources

Video Games vol. 1 no. 1, August 1982, pp. 9–10: interview with Buckner & Garcia (“Pac-Man Fever” a Top Ten single, over a million copies sold, the Japanese “Puck-Man” version).
Video Games vol. 1 no. 1, August 1982, pp. 23–26: the rules and figures (240 dots, ten points, ghost names, 100,000 machines, $2,500, about $200 million to Midway), Nakajima on the game’s origin and the name, Mullane’s objection, the November 1980 show, Jarocki, and Ms. Pac-Man’s changes and cartoons.
Video Games vol. 1 no. 3, December 1982, pp. 52–54: “The House That Pac Built”: 190,000 Pac-Man and Ms. Pac-Man machines, 94,000 Ms. Pac-Man in 1982, licensing (nearly 100 companies, 500 products, $8–10 million in 1981).
Video Games vol. 1 no. 5, February 1983, p. 98: the Crazy Otto modification and the Midway–General Computer agreement of 29 October 1981.
Retro Gamer, The Atari Book (2012): General Computer’s Crazy Otto becoming Ms. Pac-Man.
Electronic Fun with Computers & Games vol. 1 no. 1, November 1982, and vol. 1 no. 5, March 1983: Iwatani named as Pac-Man’s designer.
Edge issue 8, May 1994, pp. 54–61: Namco’s release list (Pac-Man, July 1980) and its early Famicom games.
Edge issue 65, December 1998, pp. 69–70: interview with Toru Iwatani (the pizza, the maze, one joystick, the simple character, the ghosts, the cartoons).
Edge issue 66, Christmas 1998: Iwatani joining Namco in 1977 and his early games; the claim of more than 350,000 machines.
Edge issue 217, August 2010, “When Videogames Ruled the World”: Iwatani on designing for women and the pizza; Rally-X expected to be the hit.
Wireframe issue 40, June 2020, p. 112, “Killer Feature: Pac-Man”: Iwatani’s “single file” remark, the ghosts attacking in waves, Blinky and Inky’s targets, and the Pinky bug.
Jamey Pittman, The Pac-Man Dossier, version 1.0.27, 2015 (web, secondary): how a ghost chooses its turn, the ghosts’ target squares, the four scatter phases, the “up” bug, the bonus fruit, the level 256 screen and the maximum score. https://pacman.holenet.info/
David Sheff, Game Over (GamePress edition, 1999), pp. 73 and 239–240: Time and Mad covers and the cartoon; Namco America licensing Pac-Man to Atari and Midway; Tengen’s NES Pac-Man at the June 1988 CES.
Electronic Fun with Computers & Games vol. 1 no. 3, January 1983, pp. 82–83: the Atari 400/800 version “very close to the arcade version”.
Video Games Player vol. 2 no. 1, September 1983: the biggest hits of 1982, with Pac-Man at 7 million cartridges.
Ahoy! issue 6, June 1984: Atarisoft advertisement listing Pac-Man for the Apple, IBM, Commodore 64, VIC-20, ColecoVision and TI-99/4A, “licensed to Atari, Inc. by Namco-America”.