Steve "slug" Russel had been helping McCarthy write a
Lisp interpreter for one of the main mainframes on the campus,
when he saw Minsky's program. Returning home to the Hingham
Institute (what Steve and his roommates J. Graetz and Wayne
Witanen called their tenement) and started discussing about
writing a program that really showed off the PDP-1's
capabilities. They had already been discussing some kind of
display program that was science-fiction themed. And now
McCarthy's program had expanded the possibility.
The Skylark of
Space novel that inspired
their previous discussions, they had decided to come up with
some sort of Space Warfare game, being inspired by the
Skylark of Space and "Lensman" novels of Edward E.
Smith, PhD. According to J. Graetz:
Zooming across the galaxy with our
Bergenholm Inertialess Drive, the Hingham Institute Study
Group on Space Warfare devised its Theory of Computer Toys.
A good demonstration program ought to satisfy three
It should demonstrate as many of the computer's
resources as possible, and tax those resources to the
Within a consistent framework, it should be
interesting, which means every run should be different;
It should involve the onlooker in a pleasurable and
active way -- in short, it should be a game.
With the Fenachrone hot on our ion track,
Wayne said, "Look, you need action and you need some kind of
skill level. It should be a game where you have to control
things moving around on the scope, like, oh, spaceships.
Something like an explorer game, or a race or contest... a
"SPACEWAR!" shouted Slug and I, as
the last force screen flared into the violet and went down.
The basic rules developed quickly. There would be at
least two spaceships, each controlled by a set of console
switches ("Gee, it would be nice to have a joystick or
something like that..."). The ships would have a supply of
rocket fuel and some sort of a weapon: a ray or beam,
possibly a missile. For really hopeless situations, a panic
button would be nice... hmmm... aha! Hyperspace! (What else,
after all, is there?) And that, pretty much, was that.
Almost. Steve was also pretty lazy when
it came do getting stuff done. And after some of the other
PDP-1 hackers heard about his plan for Spacewar and saw him
doing nothing with it, they got on his case. Steve's response?
Among several different excuses, his main one was he didn't
have a sine-cosine routine that would be necissary to plot
ship movement, and it was to complicated for him to sit and
start figuring out. One of the other hackers by the name of
Alan Kotok provided the solution. The MIT hackers had already
had a working relationship with DEC, since much of their
pioneering software was being given to DEC to distribute
freely with the PDP's they sold. This informal relationship
also helped when the hackers needed new parts for the PDP-1 or
other assistance, and this time it proved to be no exception.
Alan found someone at DEC with a sine-cosine routine, plopped
it in front of Steve and said "Here you are, Russell, now
what's your excuse?". With no more excuses Steve set about
in December of 1961, by January he had a small dot that you
could move around by flicking switches on the conrol panel of
the PDP-1. He then evolved the shape of the ships themselves,
coming up with a shape table routine who's concepts are still
in use in today's 3D games. He decided to make one cigar
shaped and the other like a thin tube to help differentiate
the two ships, though both were modeled after classic images
of space ships popular in the science fiction of the time.
Next he worked on the torpedo's the ships would fire
at each other, making them small dots that would fire out of
each rocket's nose and travel forward in the direction it was
shot - eventually hitting something or fading out. Steve also
pionered the idea of collision detection, creating routines to
tell when a torpedo and a ship occupied the same place,
replacing the ship with a random splatter of lines and dots to
simulate an explosion and floating debris. He also added
random dots to represent stars as a backdrop, so it was easyer
to have a sense of motion on the screen and a frame of
reference for positioning.
As February came around, he
had the basic game done after having caught the "hacker
spirit" and not only working during the latenight off hours,
but during the regular hours as well. It was at this point
though that the other hackers chimed in and contributed yet
(From left to
right) J. Graetz, Alan Kotok, and Steve Russel play
Spacewar at a reunion many years
hacker by the name of Dan Edwards thought you should have to
deal with gravity in the game because as it existed now,
however was the quickest with the controls would be the one to
win. So, he made gravity calculations and added a large star
in the center of the screen. The star would draw the ships
towards it and destroy them if they got to close. It also
allowed different strategies and maneuvers to be developed,
such as using the star to help accelerate your ship faster by
shooting around it. Graetz added the hyperspace option that
worked like a panic button and flung you to some unknown
coordinate on the screen. Peter Samson even contributed, and
decided to redo the star field. Taking the time to plot every
visible star in the night sky between 22 1/2 ∞ N and 22 1/2 ∞
S, he basicly created a computerized planetarium (nicknamed
Expensive Planetarium - a joke meaning that this expensive
equipment was being used for plotting a bunch of dots).
And thus the main code of Spacewar was finished.
Because, as with all the code written by the
hackers on both the TX-0 and PDP-1, it was placed in the
"public domain" (which basicly meant the paper tape containing
the program was stored in a publicly accessible drawer next to
the computer), the code was continuously tweaked and different
versions of the game started appearing. Such as shots
appearing in a hydrolic stream instead of one by one, or
random gravity factors, multiple gravity producing stars, and
more. The final main addition through were the introduction of
Two people playing
Spacewar in the early 1960's.
Kotok and Bob Saunders, both originaly from the TMRC
contingent, decided to create to create controllers that would
allow the hackers to play easyer than they currently had to -
basicly squeezing in at the PDP console to get at it's control
levers. So, they headed off to the TMRC room, confiscated some
switches, wires, and wood, and proceeded to create control
boxes. The completed boxes had a horizontal lever switch at
the top, a vertical one on the right side, and a fire button
towards the bottom left. The top lever was used for right and
left rotation, the right lever for accelleration and
hyperspace (depending on pulling it towards you or pushing it
away), and the fire button of course fired the torpedoes.
Finished by April of 1962, it was an addictive hit.
When not programming, many of the hackers spent hours playing
Spacewar, developing new flight strategies and maneuvers.
In a move that mimicked Willy Higginbotam's public
display 4 years earlyer, the hackers displayed Spacewar at the
MIT open house that May. The people that saw it were shocked,
since the most people had been exposed to about computers were
large room filled behemoths with blinking lights and men in
labcoats scurrying about who spoke another language from mere
mortals. Here was a game, written by students, and controlled
by a computer.
Steve had not realized what he had
accomplished until years later in the late 1960's out at
Stanford (where he had followed John McCarthy when the latter
left MIT) when he and some friends were playing pinball at a
local bar until closing time. Afterwords, they went back to
the lab and instead of programming they all fired up Spacewar.
"These people just stopped playing a
pinball machine and went to play Spacewar - by gosh, it
is a pinball machine."
had discovered was the entertainment value a computer based
game could have, and just what effect his game was to have on
As with the previously mentioned process, most
of the programs written by the hackers were shared with DEC,
and Spacewar was no exception. DEC liked it so much that they
used it to test each new PDP before it was shipped out the
door. With it running, they shut the computer off and because
of the type of memory used at that time, it would stay there.
So when the PDP reached it's destination, if everything went
right in the shipping and nothing was damaged the recipient
should be able to turn on the PDP and have Spacewar running
right away. With the paper tape copies of Spacewar being
freely distributed, by the mid 60's it had been distributed
all across the country to colleges and businesses. It even was
translated for play on other computers and their formats.
the most significant impact of Spacewar however, would be when
one Nolan Bushnell played the game while at college in Utah.
Working as a manager at an amusement park at the same time, he
came to the same realization Steve had. And it culminated in
Nolan creating the first coinoperated video game Computer
Space in 1971, (which was based off of Spacewar),
singlehandedly creating the coinoperated video game indsutry
and leading to the creation of Atari and the establishment of
video games as we now know it.
This period of computer
games at MIT forshadowed and set in motion many of the
developments to come. Most importantly the "hacker spirit" and
do it your self attitude that surrounded the creation of many
of the most loved computer and video games. Many consider
Spacewar to be the first true computer based game if not the
first video game. Whatever the definition, it's impact and the
impact of the people involved can not be denied. The muck was
swirled, and out crawled a computer game called Spacewar!