SPACEWAR! is a space combat video game developed in 1962 by Steve
Russell , in collaboration with Martin Graetz and Wayne Wiitanen, and
programmed by Russell with assistance from others including Bob
Saunders and Steve Piner. It was written for the newly installed DEC
The game features two spaceships, "the needle" and "the wedge", engaged in a dogfight while maneuvering in the gravity well of a star. Both ships are controlled by human players. Each ship has limited fuel for maneuvering and a limited number of torpedoes, and the ships follow Newtonian physics , remaining in motion even when the player is not accelerating. Flying near the star to provide a gravity assist was a common tactic. Ships are destroyed when hit by a torpedo or colliding with the star. At any time, the player can engage a hyperspace feature to move to a new, random location on the screen, though each use has an increasing chance of destroying the ship instead. The game was initially controlled with switches on the PDP-1, though Alan Kotok and Bob Saunders built an early gamepad to reduce the difficulty and awkwardness of controlling the game.
Spacewar is one of the most important and influential games in the
early history of video games . It was extremely popular in the small
programming community in the 1960s and was widely ported to other
computer systems at the time. It has also been recreated in more
modern programming languages for
* 1 Background * 2 Gameplay * 3 Development * 4 Legacy * 5 Notes * 6 References * 7 External links
Steve Russell , designer and main programmer of the initial version of Spacewar, in 2007
During the 1950s, various computer games were created in the context of academic computer and programming research and for demonstrations of computing power, especially after the introduction later in the decade of smaller and faster computers on which programs could be created and run in real time as opposed to being executed in batches. A few programs, however, while used to showcase the power of the computer they ran on were also intended as entertainment products; these were generally created by undergraduate and graduate students and university employees, such as at the Massachusetts Institute of Technology (MIT) where they were allowed on occasion to develop programs for the TX-0 experimental computer. These interactive graphical games were created by a community of programmers, many of them students and university employees affiliated with the Tech Model Railroad Club (TMRC) led by Alan Kotok , Peter Samson , and Bob Saunders. The games included Tic-Tac-Toe, which used a light pen to play a simple game of noughts and crosses against the computer, and Mouse in the Maze, which used a light pen to set up a maze of walls for a virtual mouse to traverse.
In the fall of 1961, a
Digital Equipment Corporation
Recreation of Spacewar in Java
The gameplay of Spacewar involves two monochrome spaceships called "the needle" and "the wedge", each controlled by a player, attempting to shoot one another while maneuvering on a two-dimensional plane in the gravity well of a star, set against the backdrop of a starfield. The ships fire torpedoes which are not affected by the gravitational pull of the star. The ships have a limited number of torpedoes and a limited supply of fuel, which is used when the player fires his thrusters. Torpedoes are fired one at a time by flipping a toggle switch on the computer or pressing a button on the control pad, and there is a cooldown period between launches. The ships follow Newtonian physics , remaining in motion even when the player is not accelerating, though the ships can rotate at a constant rate without inertia.
Each player controls one of the ships and must attempt to shoot down the other ship while avoiding a collision with the star. Flying near the star can provide a gravity assist to the player at the risk of misjudging the trajectory and falling into the star. If a ship moves past one edge of the screen, it reappears on the other side in a wraparound effect. A hyperspace feature, or "panic button", can be used as a last-ditch means to evade enemy torpedoes by moving the player's ship to another location on the screen after disappearing for a few seconds, but the reentry from hyperspace occurs at a random location, and in some versions there is an increasing probability of the ship exploding with each use.
Player controls include clockwise and counterclockwise rotation, forward thrust, firing torpedoes, and hyperspace. Initially these were controlled using the front-panel test switches on the PDP-1 minicomputer, with four switches for each player, but these proved to be awkward to use and wore out quickly under normal gameplay, as well as causing players to accidentally flip the computer's control and power switches. The location of the switches also left one player off to one side of the CRT display due to the limited space in front of the computer, which left them at a disadvantage. To alleviate these problems, Kotok and Saunders created a detached control device, essentially an early gamepad . The gamepad had a switch for turning left or right, another for forward thrust or hyperspace, and a torpedo launch button. The button was silent so that the opposing player would not have a warning that the player was attempting to fire a torpedo during a cooldown period.
In the fall of 1961, while brainstorming ideas for a program for the PDP-1, Russell had just finished reading the Lensman series by E. E. "Doc" Smith and thought the stories would make a good basis for the program. "His heroes had a strong tendency to get pursued by the villain across the galaxy and have to invent their way out of their problem while they were being pursued. That sort of action was the thing that suggested Spacewar. He had some very glowing descriptions of spaceship encounters and space fleet maneuvers." Other influences cited by fellow programmer Martin Graetz include E.E. Smith's Skylark novels and Japanese pulp fiction tokusatsu movies .
For the first few months after its installation, the PDP-1 programming community at MIT focused on simpler programs to work out how to create software for the computer. The community had heard of the Spacewar concept, however, and understood that Russell would spearhead the development of it. When members of the community began to feel the time was right to start work on the game, Russell, nicknamed "Slug" because of his tendency to procrastinate, began providing various excuses as to why he could not start programming the game. One of these was the lack of a trigonometric function routine needed to calculate the trajectories of the spacecraft. This prompted Alan Kotok of TMRC to call DEC, who informed him that they had such a routine already written. Kotok drove to DEC to pick up a tape containing the code, slammed it down in front of Russell, and asked what other excuses he had. Russell, later explaining that "I looked around and I didn't find an excuse, so I had to settle down and do some figuring," started writing the code in December 1961. The game was developed to meet three precepts Russell, Graetz, and Wiitanen had developed for creating a program that functioned equally well as an entertainment experience for the players and as a demonstration for spectators: to use as much of the computer's resources as possible, to be consistently interesting and therefore have every run be different, and to be entertaining and therefore a game. It took Russell, with assistance from the other programmers—including Bob Saunders and Steve Piner (but not Wiitanen, who had been called up by the United States Army Reserve )—about 200 man-hours to write the first version of Spacewar, around six weeks to develop the basic game. Excerpt from the Expensive Planetarium star charts
Russell had a program with a movable dot by January 1962, and an
early operational game with rotatable spaceships by February. The two
spaceships were designed to evoke the curvy spaceship from Buck Rogers
stories and the
The initial version of the game also did not include the central star
gravity well or the hyperspace feature; they were written by MIT
graduate student and TMRC member Dan Edwards and Graetz respectively
to add elements of a strategy to what initially was a shooter game of
pure reflexes. The initial version of the hyperspace function was
limited to three jumps, but carried no risk save possibly re-entering
the game in a dangerous position; later versions removed the limit but
added the increasing risk of destroying the ship instead of moving it.
Additionally, during this development period, Kotok and Saunders
created the gamepads for the game. The game was a multiplayer-only
game because the computer had no resources left over to handle
controlling the other ship. Similarly, other proposed additions to
the game such as a more refined explosion display upon the destruction
of a spaceship and having the torpedoes also be affected by gravity
had to be abandoned as there were not enough computer resources to
handle them while smoothly running the game. With the added features
and changes, Spacewar was essentially complete by late April 1962, and
Russell and the other programmers shifted focus from developing the
game to preparing to show it off to others such as at the MIT Science
Open House in May. The group added a time limit, as well as a
larger, second screen for viewers at the demonstration, and that same
month Graetz presented a paper about the game, "SPACEWAR! Real-Time
Capability of the PDP-1", at the first meeting of the Digital
Equipment Computer Users\' Society . The demonstration was a success,
and the game proved very popular at MIT; the laboratory that hosted
Beginning in the summer of 1962 and continuing over the next few
years, members of the
Two users playing Spacewar on a PDP-12 at the Vintage Computer Festival
Spacewar was extremely popular in the small programming community in
the 1960s and was widely recreated on other minicomputer and mainframe
computers of the time before migrating to early microcomputer systems
in the 1970s. Early computer scientist
In the early 1970s, Spacewar migrated from large computer systems to
a commercial setting as it formed the basis for the first two
coin-operated video games. While playing Spacewar at Stanford sometime
between 1966 and 1969, college student Hugh Tuck remarked that a
coin-operated version of the game would be very successful. While the
high price of a minicomputer prevented such a game from being feasible
then, in 1971 Tuck and Bill Pitts created a prototype coin-operated
Galaxy Game , with a US$20,000 PDP-11. Around the same
time, a second prototype coin-operated game based on Spacewar,
Byte magazine published an assembly language version of Spacewar in
1977 that ran on the
Altair 8800 and other
In addition to
Galaxy Game and Computer Space, numerous other games
have been directly inspired by Spacewar. These include Orbitwar
(1974, PLATO network computers),
Space Wars (1977, arcade), and Space
On March 12, 2007,
The New York Times
* ^ A B Smith, Alexander (2014-07-10). "People Get Ready, There\'s
a Train A-Coming". They Create Worlds. Archived from the original on
2015-12-22. Retrieved 2015-12-18.
* ^ A B C D E F G H I J K L M N O P Q R S T U V Graetz, J. M.
(August 1981). "The origin of Spacewar".
* Bell, C. Gordon; Mudge, J. Craig; McNamara, John E. (1978).
Computer Engineering: A DEC View of Hardware Systems Design. Digital
Press . ISBN 978-0-932376-00-8 .
* DeMaria, Rusel; Wilson, Johnny L. (December 2003). High Score!:
The Illustrated History of
Electronic Games (2nd ed.). McGraw
Hill/Osborne . ISBN 978-0-07-223172-4 .
* Donovan, Tristan (2010-04-20). Replay: The History of Video Games
. Yellow Ant. ISBN 978-0-9565072-0-4 .
* Levy, Steven (1984). Hackers: Heroes of the Computer Revolution .
Doubleday . ISBN 978-0-385-19195-1 .
* Rutter, Jason; Bryce, Jo (2006-05-09). Understanding Digital
Games. SAGE Publications. ISBN 978-1-4129-0034-8 .
* Wolf, Mark J. P. (2012-06-05). Before the Crash: Early Video Game
Wayne State University Press