Spacewar!
Spacewar! is a space combat video game developed in 1962 by Steve Russell in collaboration with Martin Graetz, Wayne Wiitanen, Bob Saunders, Steve Piner and others. It was programmed for the then newly created DEC PDP-1 minicomputer from the Massachusetts Institute of Technology. After its initial conception the game was expanded upon by other area university students and staff, such as Dan Edwards and Peter Samson. It was one of the first computer games in history and, using a version of Spacewar! on a PDP-6/PDP-10, the first recorded video game championship was held in 1972..
In the game two spaceships, "The Needle" and "The Wedge", engage in battle while maneuvering around a star's gravity well. Both ships are controlled by people. Each ship has a limited amount of weaponry and fuel to maneuver and the ships are in motion even when the player does not perform any acceleration. One of the most common tactics during the game was to fly close to the star to get gravity assist. Ships are destroyed when they collide with a torpedo, the star, or each other. At any time, players can activate a "hyperspace" ability to instantly move to another random place on the screen, although in some versions each use of this functionality increases the chance that instead of moving the ship will be destroyed. Originally the game was controlled with switches on the PDP-1, although Bob Saunders built a primitive controller to reduce its difficulty and make the game easier to control.
It is one of the most important and influential games in the history of early video games. It was extremely popular in the small programming community in the 1960s, and its public domain code was redesigned and ported to other computer systems of the time, especially after the rise of monitor systems at the end of the decade. It has also been reproduced in more modern programming languages with emulators for the PDP-1. It was the direct inspiration for many other electronic games, such as the first commercial arcade video games, Galaxy Game and Computer Space (1971), or later games such as the popular Asteroids (1979). In 2007 Spacewar! was included in a list of the ten most important video games of all time, a list that constituted the beginning of the game canon of the Library of Congress of the United States, a list of video games that this institution considers should be preserved.
Background
During the 1950s, a number of computer games were created in the context of academic research on computing and programming and to demonstrate the power of computers, especially after the advent of smaller computers at the end of the decade. size and faster in that programs could be created and executed in real time, rather than by batch processing. However, in some cases, programs designed both to test the power of the computer on which they were run and to be used as an entertainment product were designed, generally programmed by undergraduate and graduate students and by university personnel, as in the case at the Massachusetts Institute of Technology (MIT), where staff and students could occasionally develop programs for the experimental TX-0 computer developed at the Institute's Lincoln Laboratory. These interactive graphical games were created by a community programmers, many of them university students and employees belonging to the Tech Model Railroad Club (TMRC) led by Alan Kotok, Peter Samson and Bob Saunders. Among these games were Tic-Tac-Toe, which used a stylus to play a simple game of tic-tac-toe against the computer, or Mouse in the Maze, that used the stylus to create a maze of walls that a virtual mouse had to navigate.
In September 1961, a Digital Equipment Corporation (DEC) PDP-1 minicomputer was installed in the "kludge room" on the second floor of Building 26, where the Department of Electrical Engineering was located. MIT. The PDP-1 was to complement the old TX-0 and, like it, it had a punched tape reader and recorder and also allowed inputs from a switch panel and output to a cathode ray tube monitor. During the summer before the arrival of the computer, a group of students and employees of the university had been considering ideas to develop programs that would demonstrate the capabilities of the new computer in a convincing way; three of them—Steve Russell, then a Harvard University employee and former MIT research assistant; Martin Graetz, research assistant and former MIT student; and Wayne Wiitanen, a Harvard research assistant and former MIT employee and student—conceived the idea for Spacewar! They called their partnership the "Hingham Institute," since Graetz and Wiitanen lived in a tenement building located on Hingham Street in Cambridge, Massachusetts. "We had a brand new PDP-1," said Steve Russell in an interview for Rolling Stone in 1972. little pattern generating programs that created interesting patterns like a kaleidoscope. It wasn't a very good show. We had this screen that could do all kinds of wonders. So we started talking about it, thinking about what would make an interesting visualization. We decided that a two-dimensional type of maneuver could probably be done and we decided that naturally the most obvious thing was spaceships."
The Game
The game consists of two monochrome spaceships, the needle and the wedge), each controlled by a player, attempting to shoot each other while maneuvering in a two-dimensional plane around a star's gravity well, with a star field as a background. Ships can fire torpedoes, which are unaffected by the star's gravitational pull; they have a limited number of torpedoes and fuel, which is consumed when the player activates the ship's thrusters. While attempting to control the ship's rotation for aiming, torpedoes are fired one at a time by pressing a switch on the computer or a button on the controller and between each launch there is a cooldown period. The ships keep moving even when the player is not accelerating and the rotation of the ships does not change the direction of their movement.
Each player controls one of the ships and must try to shoot down the other while avoiding colliding with the star or the opposing ship. Flying close to the star can provide gravity assist to the player and increase the ship's speed, albeit at the risk of misjudging the trajectory and ending up falling into the star. If a ship reaches the edge of the screen it respawns on the opposite side, maintaining speed and trajectory.
At any time players can activate the hyperspace or "panic button" function, which can be used as a last resort to avoid enemy torpedoes by making their ship instantly disappear and respawn in another random place on the screen, although in some cases versions of the game each use of this functionality increases the possibility that, instead of making a reentry from hyperspace, the ship will be destroyed.
The control elements available to each player are rotating the ship clockwise and counterclockwise, thrusting forward, firing torpedoes, and entering hyperspace. Initially the ships they were controlled by the test switches on the front panel of the PDP-1 minicomputer (four switches for each player), but these were cumbersome to use and quickly degraded during normal gameplay, as well as causing players to accidentally press the switches computer control and power supply. In addition, the position of the switches forced one of the players to stand to the side of the CRT monitor, due to the limited space in front of the computer, which put him at a disadvantage in the game. To alleviate these problems, Saunders created a stand-alone control device, essentially a primitive gamepad. torpedo launch button; when pressed, the button made no noise so that the opposing player would not perceive that the player was attempting to launch a torpedo during a cooldown period.
Development
.jpg)
Russell, Graetz, and Wiitanen developed the basic idea for Spacewar! in the summer of 1961, in anticipation of the addition of the PDP-1. Russell had recently finished reading the series Lensman by E. E. "Doc" Smith and thought these stories would make a good foundation for the show: "His heroes had a marked tendency to be chased across the galaxy by the villain and to have to figure out a way out of their problem while being persecuted. That kind of action was what inspired me Spacewar! It had some very brilliant descriptions of ship encounters and space fleet maneuvers." His programming partner Martin Graetz cites other influences, such as novels by the Skylark series by E. E. Smith and the Japanese science fiction tokusatsu films.
In the first few months after the new computer was installed, the PDP-1 programming community at MIT focused on simpler programs to determine how to develop software for the computer. During this period, Russell frequently visited his old friends in the community and outlined the idea for Spacewar! to them. Russell hoped someone else would implement the game, as he had no plans to do it himself. However some members of the community felt that he was the logical choice to create the game and began to push him to program it, but Russell gave some excuses as to why he couldn't do it, such as not having a function routine. trigonometric data needed to calculate the trajectories of spacecraft. This led Alan Kotok of the TMRC to contact DEC, where they informed him that such a routine was already available; Kotok went to DEC to collect a tape containing the code, deposited it in front of Russell, and asked what other excuses he had. Russell—later stating, "I looked around and couldn't find any excuses, so I had to I have to sit down and do some calculations"—he began writing the code around the time the PDP-1 monitor was installed in December 1961. The game was developed around three precepts that Russell, Graetz, and Wiitanen had established for create a program that would work both as an entertainment experience for players and as a demo for the public: use as much of the computer's resources as possible and push them to the limit; following a coherent scheme, it had to be interesting, so each execution had to be different; it had to involve the observer in a pleasant and active way; in short, it had to be a game. To Russell, with the help of the other programmers such as Bob Saunders and Steve Piner—but not Wiitanen, who had been called up by the United States Army Reserve—, it took him about 200 hours in total to write the first version of Spacewar!, that is, he spent about six weeks to develop the basic game. The program was written in the PDP-1 assembly language.
Russell developed a first program of moving objects in January 1962, which was just a point that could accelerate and change direction by means of a switch and in February he already had a first working version of the game, with spaceships that rotated, fuel supply, and torpedoes. The two spacecraft were designed to evoke the curved spaceship from the Buck Rogers stories and the PGM-11 Redstone rocket. This early version also featured a randomly generated background star field, added initially by Russell because a white background made it difficult to appreciate the relative motion of the two ships at low speed. The programming community in the area, including the "Hingham Institute" and the TMRC, had embraced what later came to be called the hacker ethic, under which all programs were freely shared and modified by other programmers in a collaborative environment, without concern for ownership or copyright, which led to group work to refine the initial Spacewar! TMRC member Peter Samson was not convinced by the imprecision and unreality of the star field, so he wrote a program based on real star charts that slowly scrolled across the night sky, including each star in a band between 22.5° N and 22.5° S to fifth magnitude, displayed with its relative brightness; the program was called Expensive Planetarium—"Expensive Planetarium", in reference to the high price of the PDP-1 computer compared to an analog planetarium and as part of the series of "expensive" programs such as Expensive Typewriter or Expensive Desk Calculator—and was incorporated to the game in March by Russell, who acted as the lead for the initial build of the game.
The initial version of the game also did not include the central star gravity well or the hyperspace entry option, which were developed respectively by MIT graduate student Dan Edwards and TMRC member Graetz for this purpose. adding elements of strategy to what was initially a reflex-only shooter. The first version of the hyperspace feature was limited to three jumps, but carried no risk other than re-entering the game in a dangerous position; later versions removed the limit, but added an increased risk of destroying the ship instead of moving it. In March 1962 Saunders designed a primitive gamepad for the game, in order to avoid the appearance of the "Space War Elbow" (space battle elbow) that caused sitting hunched over the buttons on the computer panel. central. The game only had the multiplayer option, because the computer did not have enough resources to control the other ship on its own. In the same way, other proposals to improve the game, such as a more accurate visualization of the explosions after the destruction of a spaceship or the torpedoes were also affected by gravity, they had to be discarded since they did not have enough computing resources to manage them and for the game to run smoothly. With the added features and improvements, Spacewar! was available for students and visitors to play in late April 1962. Russell and the other programmers stopped developing the game and began showing it off to other people, such as during the MIT Open House in May. The group added a time limit, hyperspace functionality, and a second, larger screen for viewers during the demo, and Graetz gave a talk about the game later that month., «SPACEWAR! Real-Time Capability of the PDP-1", at the first DECUS meeting. The demo was a success and the game became very popular at MIT; the lab that housed PDP-1 was quick to ban the game except during lunch and after work hours. Visitors such as Frederik Pohl enjoyed playing the "charming game"; the editor of Galaxy Science Fiction reported that MIT was "taking ideas from science fiction magazines" since players could imagine they were characters from Skylark.
Beginning in the summer of 1962 and over the next several years, members of the MIT PDP-1 programming community, including Russell and the other members of the Hingham Institute, began to spread out to other schools and companies such as Stanford University or DEC, and as they did, they spread the game to other universities and institutions that had a PDP-1 computer. As a result, Spacewar! was perhaps the first video game that became available outside of a single research institute. Over the next decade programmers at other institutions began coding their own variants, including features such as allowing more ships and players at once, replacing the hyperspace feature with a cloaking, space mines, and even a first-person perspective version that was played on two monitors and simulated the vision of each pilot outside the cockpit. Some of these implementations of the game also replicated the gamepad from Saunders. DEC learned of the game shortly after its creation and used it to demonstrate its operation on its PDP-1, as well as publishing a brochure about the game and the computer in 1963. According to a Second-hand account that came to Russell while working at DEC, company technicians used Spacewar! as a smoke test on new PDP-1 systems prior to shipment, as it was the only available program that used all the resources of your hardware.
Expansion and legacy
Spacewar! was extremely popular in the small computing community of the 1960s and thanks to its popularity among programmers it was widely replicated on other minicomputers and mainframes of the era before porting it to early microcomputer systems in the 1970s.
As during its development, the game was in the public domain and the source code was available to anyone who had access to it or contacted Russell; no attempt was made to commercialize it, as the programming community was too small to support commercial endeavor. Initially it was spread both by people taking copies of the code to other facilities and by programmers reproducing the game with their own code. Early installations included the PDP-1 by Bolt, Beranek and Newman, which also reproduced the gamepads; a Russell installation on a PDP-1 at the Stanford University Artificial Intelligence Laboratory in 1963; or the University of Minnesota, where MIT graduate Albert Kuhfield reproduced the game for CDC 3100 in 1967-68 and submitted a description to Analog Science Fiction and Fact, which published it in 1971. The Stanford installation was so popular that, in 1966, the researchers created a special "Spacewar mode" to share computing resources on their PDP-6, so that it could be played while it was running. research programs. Alan Kay, one of the first theoretical computer scientists, said in 1972 that "Spacewar! springs up spontaneously wherever there is a graphical display connected to a computer" and Graetz recalled in 1981 that when it began e widespread during its early days the game could be found on "almost any research computer that had a programmable CRT".
Although the game was very widespread for the time, its direct reach was very limited because, although it was less expensive than most mainframes, the PDP-1 was priced at 120,000 dollars (approximately 1,014,000 2019 dollars) and only 53 units were sold, most without a monitor and many in secure military installations or in research laboratories that did not allow free-time use of the computer, which prevented the The original version of the game reached beyond a small academic community. Although some later DEC models, such as the PDP-6, came with Spacewar! preloaded, the audience for the game was still very limited. —of the PDP-6 only 23 units were sold. The boom in its diffusion took place several years after the initial development of the game; Starting in 1967, computers connected to monitors or terminals capable of running Spacewar! began to proliferate, allowing the game to reach a wider audience and influence subsequent video game designers —in 1971, it is estimated that there were already over 1,000 monitor computers, instead of a few dozen. It was around this time that most variants of the game were created for various computer systems, such as later models of PDP systems, and by 1972 the game was well known in the programming community for Rolling Stone to sponsor the "Intergalactic Spacewar! October 1972 at the Stanford Artificial Intelligence Laboratory using a variant of the game on a combined PDP-6/PDP-10 that allowed five players to connect, thus becoming the first video game tournament in history, from which published a story in the December 7, 1972 issue of the magazine.
In the early 1970s, the game moved from major computer systems to commercial realm, as it formed the basis of the first two coin-operated video games. While playing Spacewar! at Stanford sometime between 1966 and 1969, college student Hugh Tuck commented that a coin-operated version of the game would be very successful. Although the high price of a minicomputer prevented a game of this type from being viable at the time, in 1971 Tuck and Bill Pitts created a prototype computer game with a $20,000 PDP-11 (about $126,000 in 2019). The coin-operated Galaxy Game, though they never produced more than the two prototypes they exhibited at Stanford. Around the same time, Nolan Bushnell and Ted Dabney developed a second coin-operated game prototype based on Galaxy Game. i>Spacewar!, Computer Space, which would become the first commercially sold arcade game and the first widely released video game of any kind. Although Tuck considered that Computer Space was a poor imitation of Spacewar! and its Galaxy Game a superior adaptation, many gamers believed that both arcade games were updated variants of Spacewar! in any case. i>Spacewar!
Byte magazine published in 1977 an assembly language version of the game that ran on the Altair 8800 and other Intel 8080-based microcomputers, using an oscilloscope as a graphical display and a table of query to approximate calculations of orbits, as well as a 3D variant in 1979 written in Tiny BASIC. More modern versions of the game have also been made for personal computers. In 2012 a ported version of the original game was made available to the public. Released by Martin Graetz and running on a JavaScript PDP-1 emulator, it was offered for free play using a web browser. The only known working PDP-1s are held at the Mountain View Computer History Museum (California), where demonstrations of the machine are held, including playing Spacewar!
Apart from Galaxy Game and Computer Space, Spacewar! has had a great impact and has inspired many other games, such as Orbitwar (1974, PLATO network), Space Wars (1977, arcade), Space War (1978, Atari 2600), or Star Control (1990, cross-platform). Additionally, in the popular and later cross-platform arcade game Asteroids (1979) designer Ed Logg used elements of Spacewar! , specifically the hyperspace button and the shape of the player's ship. Russell has been quoted as saying that the aspect of the game that he is most satisfied with is the number of programmers he has inspired to develop their own games. without feeling restricted to use your design or code.
On March 12, 2007 The New York Times published that Spacewar! was part of a list of the ten most important video games of all time, the so-called « game canon", and proposed that it be preserved in the United States Library of Congress. The Library picked up this video game preservation proposal and started it with the games on this list. On November 29, 2018, the Academy of Interactive Arts & Sciences awarded the Pioneer Award, given to "individuals whose career work has helped shape and define the interactive entertainment industry", to the surviving contributors to the design of Spacewar!: Dan Edwards, Martin Graetz, Steven Piner, Steve Russell, Peter Samson, Robert Sanders, and Wayne Wiitanen.