Board games

Much of our country’s computing power is spent playing games. Here’s why.…

Shannon’s trees

In 1950, Claude Shannon proposed a way to make the computer win at checkers, chess, and other complicated games.

To understand his method, let’s try to make the computer win a game of checkers. As in all checker tournaments, one player is called BLACK, and the other is called WHITE (even though his pieces are actually red). BLACK makes the first move. When a player can jump, he must. The game ends when one of the players can’t move (either because he has no pieces or because his pieces are blocked).

To simplify the game, we’ll play on a 4-by-4 board, instead of the traditional 8-by-8. Each player has two pieces instead of twelve.

This diagram shows 63 possible positions:

Position #1 is the initial position, from which black will move. The three arrows coming from position #1 represent the three legal moves he can choose from. Depending on which move he chooses, the board will wind up in position #2 or #3 or #4. Which move is best?

If he moves to position #2, white will reply by moving to position #5 or #6 or #7.

If he moves to position #3, white will reply by moving to position #8 or #9 or #10.

If he moves to position #4, white will reply by moving to position #11 or #12 or #13.

Which position should black choose: #2, #3, or #4? The wisdom of your answer depends on how deep you make the tree. In this particular game, a depth of 5 is satisfactory; but in 8-by-8 checkers or chess you might have to dig deeper. Theoretically, you should keep digging until you reach the end of the game; but such a tree might be too large to fit in your computer’s memory.

For chess, Shannon estimated that a complete tree requires 10¹²⁰ branches. Einstein estimated that the number of electrons in the universe is only 10¹¹⁰. If Shannon and Einstein are both right, the tree can’t fit in the universe!

Having constructed a tree of depth 5, look at the bottom positions (#42 through #63) and evaluate them, to see which positions look favorable for black. You should consider many factors: which player has control of the center of the board? which player can move the most without being jumped? and so on. But to keep matters simple, let’s consider just one factor: which player has the most men? Consider a king to be worth 1½ men.

For example, consider position #42. Since black has one man and white has two, the value is 1 minus 2, which is -1. That’s why I’ve written "v=-1" underneath that position. The value of each position at depth=5 is computed by that method.

For the positions at depth=4, use a different method. For example, here’s how to find the value of position #29. That position has two possible outcomes: #46 and #47. Which outcome is more likely? Since the move will be made by black, and black’s goal is to make the value large, he’ll prefer to move to #46 instead of #47. Since the most likely outcome is #46, whose value is ½, assign position #29 a value of ½ also.

Here’s the rule: to compute the value of a position at depth=4, find the maximum value of the positions it points to. (The value of position #29 is the maximum value of positions #46 and #47, which is ½.)

To compute the value of a position at depth=3, find the minimum value of the positions it points to (since it’s white’s turn to move, and white wants to minimize). For example, the value of position #18 is the minimum value of positions #31 and #32, which is 1½.

Compute the values for depth 2 by maximizing, and the values for depth 1 by minimizing. Finally, you get these results:

The value of position #2 is -1.

The value of position #3 is 0.

The value of position #4 is -1½.

Since black wants to maximize values, black should move to position #3. If white is also a good player, the game will probably gravitate toward position #53, a draw. If white is a poorer player, black will win.

Samuel’s checkers

After Shannon, the next person to become famous was Arthur Samuel. He spent a long time (twenty years, from 1947 to 1967) trying to make the computer win checkers. He used Shannon’s minimax idea, but made many improvements.

His first spectacular success came in 1962, when his program won a game against Robert Nealey, a former Connecticut checkers champion. After the game, Nealey said "The computer had to make several star moves in order to get the win.… In the matter of the end game, I have not had such competition from any human being since 1954, when I lost my last game."

Later, the computer played six more games against Nealey. Nealey won one of them; the other five were draws.

In 1965 the computer played four games against W.F. Hellman, the World Champion. The games were played by mail. Under those conditions, Hellman won all four. But in a hastily played game where Hellman sat across the board from the computer, the result was a draw.

In 1967 the computer was beaten by the Pacific Coast Champion, K.D. Hanson, twice.

In short, the computer wins against most humans and draws against most experts, though it loses to the top champions. To bring the computer to that level of intelligence, Samuel improved Shannon’s method in three ways.…

1. When choosing among several moves, the computer analyzes the most promising ones more deeply.

2. After computing the value of a position (by examining the positions under it), the computer writes the value on a piece of tape. If the position recurs in another game, the computer looks at the tape instead of repeating the analysis.

3. To compute the value of a position, the computer examines many factors in addition to the number of pieces each player has. The computer combines the factors, to form combination-factors, and then combines the combination-factors to form a single value. The relative importance given to each factor is determined by "experience". Samuel experimented with two forms of experience: he had the computer play against itself, and also had it analyze 250,000 moves that occurred in checker championships.

Chess

While Samuel was programming checkers, other programmers tried to write a similar program for chess. They had a hard time. In 1960 the best chess program that had been written was beaten by a ten-year-old kid who was a novice.

But in most tournaments, it lost. In 1970 and 1971, it lost every game in every tournament it entered.

Their program played chess against human experts — and occasionally won! Their computer scored several triumphs in tournaments designed for humans.

In 1976, their computer won the class B section of the Paul Masson American Chess Championships. Against the humans in that tournament, it scored 5 wins, no losses. By winning that tournament, it achieved a U.S. Chess Federation score of 2210 and became a chess Master.

Then it entered the Minnesota State Championship, to try to become the Minnesota State Champion, but lost (it scored 1 win, 3 losses, 1 tie).

In August 1968, an International Chess Master, David Levy, bet about $5,000 against several computerists. He bet that no computer would win a chess match against him in the next ten years. He won the bet: in August 1978, Chess 4.7 tried one last time to win a match against him, but lost (it scored 1 win, 3 losses, 1 tie).

But though it was the world champion of computer chess, it was not necessarily the "best" program. It won because it ran on a super-fast maxicomputer (manufactured by Control Data Corporation). Other chess programs, written for slower computers, were at a disadvantage.

When you play against the computer by using Sargon 4, Chessmaster 2100, or Chessmaster 3000, you can ask the computer for help by pressing a special key. Then the computer will tell you how it would move if it were in your position. You can follow the computer’s suggestion or ignore it. Since your goal is to outsmart the computer, you should listen to the computer’s advice; but instead of following the advice, try to devise a move that’s even cleverer!

Many companies make hand-held electronic chess games. Some of the games even contain a tiny voice synthesizer, which lets the computer tell you its moves verbally. Some of the games even contain a mechanical arm, so that the computer will pick up the pieces and move them. Some of the games have touch-sensitive boards, so that you can indicate your move by just pushing the square you want to move from and the square you want to move to. For humor, some of the chess games have the computer make wisecracks about your style of playing.

Choose a level

When you begin playing a top-notch computer game (such as Chessmaster 3000), you must choose the "level" at which you want the computer to play. If you choose a low level, the computer will move quickly, without much forethought. If you choose a high level, the computer will play more carefully (and make better moves); to do that, the computer "looks ahead", by building a very large tree, which requires lots of time; and so you must wait a long time until the computer moves. If you choose a level that’s very high, the computer will need several hours to compute its move.

Why a computer?

Playing against the computer is more interesting than playing against a human.

When you play against a human friend, you must wait a long time for your friend to move. When you play against Chessmaster 3000 at a low level, the computer moves almost immediately. So you can play several games against the computer (and learn a lot from them) in the same amount of time you’d need to play just one game against a human. So by playing against the computer, you gain experience faster than by playing against a human. Bobby Fischer, who became the world chess champion, now plays only against computers; he refuses to play against humans and hasn’t defended his title.

The computer is kinder than a human. If you make a bad move, the computer lets you "take it back" and try again. If you seem to be losing, the computer lets you restart the whole game. The computer — unlike a human — has infinite patience and no ego. Playing against the computer is less threatening than playing against a human.

If you have a computer, you don’t have to worry about finding an opponent who’s "at your level"; when you play against the computer, just tell the computer at what level you want it to play. The computer will act about as smart as you wish.

Othello

When the game begins, only four checkers are on the board: two of them have their white side showing, and the other two checkers show black.

The game is for two players. One is called the white player, and the other is called the black player.

For example, suppose you’re the white player. On your turn, you put an extra checker onto the board, so that the checker shows white. You must position the checker so that it and a previously placed white checker surround some black checkers. Then you flip all the surrounded black checkers, so that they become white.

Similarly, on his turn, the black player puts a black checker onto the board, so that some of your white checkers are surrounded by black, and he flips all those white checkers, so that they become black.

The game ends when the board is entirely filled with checkers. If most of the checkers are white, the white player wins; otherwise, black wins.

The game is tricky, because the definition of "surrounded checkers" is strange, and because you can’t easily figure out who’s winning. At first glance, you’d think that if most of the checkers on the checkerboard are white, white is ahead; but at the end of the game, the situation can change drastically. For example, the black player might place a black checker in such a way that most of the white checkers become black. So you must guard against dangerous positions. During the early parts of the game, the white checkers’ positions are more important than their quantity.

Unfortunately, Hayden’s become part of Spinnaker, which has stopped publishing the program, because most people have forgotten how to play Othello and no longer want to play. Too bad! It was a fun game.

Backgammon

The human was a poor loser: he blamed it on "bad luck". He refuses to admit that the computer has more skill than he. Nevertheless, the computer is now the world champion.

Adventure games

Adventure is a game where you hunt for some sort of "treasure".

Original Adventure

The original version of Adventure was written by Will Crowther & Don Woods, on a PDP-10 maxicomputer at Stanford University’s Artificial Intelligence Lab.

The first time you play this game, you feel lost — the game’s an adventure. As you wander in whatever direction you please, the computer says you’re going through forests, across streams, over hills, etc.

To find the keys, the typical stupid player tries wandering through the forests and valleys again. But if you’re smart, you’ll remember that at the beginning of the adventure you were next to a shack. So you go back to the shack, walk inside, and find keys! So you trek back to iron grate, and use the keys to get in. You think — aha! — you’ve succeeded!

But actually, you’ve just begun! The grate leads you into a cave that contains 130 rooms, which form a big three-dimensional maze. Lying in the maze are 15 buried treasures; but as you walk through the maze, you can easily forget where you are and where you’ve come from; you can waste lots of time just walking in circles, without realizing it!

To add to the challenge, the cave contains many dangers, such as trap doors (if you fall in, you break every bone in your body!) and trolls & snakes, which you must ward off by using various devices that you must find in the cave’s rooms or even back at the shack. Yes, you might have to trek all the way back to the shack again!

Finally, after dodging all the evil things in the cave, you reach the treasures. You grab them up and start walking away with them. But then you hear footsteps behind you, and pirates steal your treasures! Then you must chase the pirates.

If you manage to keep your treasures and your life and get out of the cave, you haven’t necessarily won. The nasty computer keeps score of how well you retrieve the treasures. The maximum possible score is 350. After you’ve played this game many times and learned how to duck all your adversaries quickly, you’ll find you scored just 349 points, and you’ll wonder what you did wrong that cost you 1 point. The answer is: during the adventure, you must borrow magazines from a room in the cave; to get the extra point, you must return them!

The game’s a true adventure, because as you wander through forests and the rooms in the cave, the computer tells what you see, but you don’t know whether what you see is important. For example, when you walk into a room, the computer might say the room contains a small cage. That’s all it says. You must guess whether the cage has any significance and what to do to the cage, if anything. Should you pick it up? Try to break it? Kiss it? Carry it? Try anything you like — give any command to your computer-body that you wish — and see what happens.

Here’s a list of the most useful commands:

Throughout the game, you get beautifully lyrical writing. For example, the computer describes one of the rooms as follows: "You are in a splendid chamber thirty feet high. The walls are frozen rivers of orange stone."

Microcomputer versions

Although Adventure was originally written for a PDP-10 maxicomputer, you can get an exact imitation for microcomputers.

Infocom

Like Adventure, Zork originally ran on a PDP-10 computer. Infocom has published versions of Zork for microcomputers. Versions for the IBM PC, Mac, Apple 2e & 2c, Apple Macintosh, Commodore Amiga, Atari ST, and Radio Shack Models 3 & 4 cost $39.95. Versions for the Commodore 64, Atari 800 XL, and Radio Shack Color Computer 2 cost just $34.95.

Infocom was an independent company but has been acquired by Activision.

Sierra On-Line

You use a computerized "time machine", which transports you to 9 times (400 million B.C., 10000 B.C., 50 B.C., 1000 A.D., 1400, 1700, 1982, 2082, and 4082) and 8 locations (North America, South America, Europe, Africa, Asia, Australia, Antarctica, and Outer Space).

Wherever you go, your screen shows a high-resolution color picture of where you are. For example, if you choose "approximately 1400", Christopher Columbus will welcome you aboard his ship. Altogether, the game contains over 1400 pictures! You travel through history, searching for clues that help you win.

Time Zone is historically accurate and doesn’t let you cheat. For example, when you find a book of matches in the year 2082, your time machine will let you carry the matches back to 1982 but not to 1700 — since matches weren’t invented until 1800.

Living through history isn’t easy. Jonathan Rotenberg, chairman of the Boston Computer Society, played the game and said:

I’ve been killed dozens of times. I’ve been assassinated by Brazilian terrorists, karate-chopped by a Brazilian monk, eaten by a tyrannosaur, crushed in an Andes avalanche, stampeded by a buffalo, overcome by Antarctic frostbite, and harpooned by Mayan fishermen.

And you see it all in color!

Time Zone sold for $99.95. Alas, teenagers didn’t buy it, because it took too long to win and was too expensive. Sierra On-Line has stopped selling it.

Recently, Sierra On-Line has made Softporn Adventure even more exciting, by adding graphics. Here’s what the new graphic versions are called.…

Leisure Suit Larry in the Land of the Lounge Lizards

Leisure Suit Larry 2: Looking for Love in all the Wrong Places

Leisure Suit Larry 3: Passionate Patti in Pursuit of the Pulsating Pectorals

Creative Computing

Although Dave and his friends all love to play the game, the Actors Guild refuses to let Dave sell the game to strangers. The Guild claims that when Dave shows the scenes in an order different from the original movie’s, he’s destroying the "artistic integrity" of the actors’ performances.

Ha! Does the Guild really believe that a grade-B horror flick has any artistic integrity at all?

Spinnaker

The Perry Mason one, besides being fun, also trains you to become a lawyer:

To make sure you understand those six ways to object, the handbook includes a multiple-choice test about them. The test is titled "Study Guide for the California Bar Exam".

The game also lets you invent your own questions for the witnesses and give commands to your secretary (Della Street) and detective (Paul Drake).

Broderbund

To help you understand those 30 cities, the game comes with a geography book: the 928-page unabridged edition of The World Almanac and Book of Facts.

As you play the game, you unearth clues about which cities the thieves are fleeing to. But to use the clues, you must look up facts in the almanac. By playing the game, you learn how to use an almanac, and also learn geography. When you figure out which city to travel to, the screen shows a map of the world, shows you traveling to the city, and then shows a snapshot of what the city looks like, so that the game also acts as a travelogue.

Because the game is so educational, it’s won awards from Classroom Computer Learning Magazine and the Software Publishers Association.

Strictly speaking, it’s not a true adventure game, since it does not let you input your own words and phrases. Instead, you just choose from menus, which make the game easier for youngsters.

For the Apple 2 family and IBM PC, the original version costs $39.95, and the sequels cost $44.95 each. For the Commodore 64, you pay $5 less. Those are the list prices; discount dealers charge even less.

Electronic Arts

Here’s the plot:

When you start playing Amnesia, you wake up in a hotel room in New York City. You discover you have no clothes (you’re stark naked), no money (you’re flat broke), and no recollection of who you are — because you’re suffering from amnesia. You don’t even remember your name.

You look at yourself, and notice you’re a male. Your first problem is to get some clothes and money. But then you learn you have other problems that are even more serious. For example, you get a call from a guy who reminds you that today is your wedding day, and that if you don’t hurry up and marry his daughter without further mess-ups, he’ll use his pistol. You also discover that the FBI is looking for you, because the state of Texas has reported that you’re a murderer.

After getting some clothes (so you can stop scaring the hotel’s maids), there are several ways to get out of your jam. (I’ve tried them all!)

One way is to say "yes" to the pistol-packing papa and marry his daughter, who takes you to Australia, where you live on a sheep ranch for the rest of your life. But then you never learn who you really are! Whenever you ask your wife about your past, she simply says, "You wouldn’t want to know." You die of old age, peacefully; but even on your deathbed, you don’t learn who you are; and so when you die, you feel sad. In that case, you score lots of points for survival, but zero for detective work and zero for character development.

A different solution is to say "no" to the bride and — after getting bloodied — run out of the hotel, onto the streets of New York. Then the fun begins — because hiding on the program’s disks is a complete map of Manhattan (from Battery Park all the way up to 110th Street), including all the streets and landmarks and even all the subway stops! Yes, this gigantic game includes 94 subway stations, 200 landmarks, and 3,545 street corners.

As you walk one block north, then one block east, etc., the computer describes everything you pass, even the most sublime (The Museum of Modern Art) and the most ridiculous (Nedick’s hamburger stands). You can ride the subway — after you get enough money to buy a token. The game even includes all the subway signs, such as "Downtown — Brooklyn" and "Uptown — Queens". To catch the E train, you must hop in as soon as it arrives. Otherwise, it departs without you, and the computer says "an F train comes" instead.

As night falls, the computer warns you to find a place to sleep. (You can’t go back to your hotel, since you’re in trouble there.) To find a free place to stay, you can try phoning the names in your address book — once you find a phone booth, and get a quarter to pay for each call. The address book contains 17 listings: J.A., A.A., Chelsea H., drugs, F°, Sue G., E.H., interlude, kvetch, J.L., R & J, sex, soft, Lila T., T.T.T.T., and Wit’s End. Each of those listings is an adventure in itself. You must explore each of them thoroughly, to fully discover who you really are.

If your body ever gets weak (from sleeplessness or hunger or being hit by too many muggers), you faint on the sidewalk, wake up in a hospital, and get found there by the FBI, which returns you to the state of Texas, which executes you for murder. But even that deadly ending has a cheery note. For example, you can choose your last meal: would you like steak and potatoes, or turkey? When you finally die, you can wind up in purgatory, which consists mainly of getting mosquito bites, with an opportunity to take a rowboat to heaven, if you can just remember your real name and tell the boatman.

The entire adventure has the structure of a good novel: a gripping introduction (you’re a nude, broke, amnesiac groom in a hotel), a thorough development section (wandering through the streets of New York, searching for your identity and the meaning of life), and a conclusion (a whimsical death scene, or something better).

The text was written by Thomas Disch, the award-winning sci-fi novelist. It’s lyrical. For example, when you escape from the hotel and walk out onto the streets of New York, the computer says: "It feels great to be a single faceless, nameless atom among the million others churning about in the grid of Manhattan’s streets. It feels safe."

The game combines all our nightmares about New York into a wild, exciting adventure.

The game’s affected my own life. Now whenever something in my life goes wrong, instead of groaning I just say, "I’m in another wild part of Amnesia!" In Amnesia, as in life, the only way to score top points for living is to experience it all. To live life to the fullest, you must take risks, have the courage to face unknown dangers, and revel in the excitement of the unexpected.

Though Amnesia received lots of praise from reviewers, sales were disappointing. Electronic Arts stopped publishing it. I bet if they’d rename it "Lost in New York", it would sell well — at least in New York!

Modern graphics adventures

Modern graphics adventures come on CD-ROMs and include video clips of actual people, with actual sounds, supplemented by wildly beautiful and detailed graphics. They’re interactive movies — partly real, partly animated — where you control the action!

The world of computer games is changing rapidly! For further details about what’s new & coming, get on the mailing list to receive info about the next edition of The Secret Guide to Computers, by using the coupon on the back page.

Action games

Hey! Let’s have some action!

Arcade games

Each year’s arcade games reflect the latest fads. For example, you can play arcade games about break-dancing and kung-fu.

Game watch

When your colleagues see you looking at your watch, they’ll think you’re an impatient executive tracking the time. Meanwhile, you’re just having fun!

Olympics

In his game, one of your fingers represents your left leg, and another finger represents your right leg. To "run", you tap those fingers (left, right, left, right) as quickly as possible on the keyboard. By using those fingers and others, you compete in all ten events: the 100-meter dash, long jump, shot-put, high jump, 400-meter dash, 110-meter hurdles, discus throw, pole vault, javelin throw, and 1500-meter run. You can play solo or against your friends. At parties, you can form teams and cheer each other on.

Later, he wrote versions for the Apple 2 and the IBM PC. They’re published by Microsoft.

Sports heroes

From Doom to Quake

Though Doom is violent, it has a sense of humor. For example, you can choose 5 levels of difficulty: the beginner level, where you can’t get hurt, is called "I’m too young to die". The next step up is called "Hey, not too rough." Then comes "Hurt me plenty", then "Ultra-violence", and finally the expert level, called "Nightmare!" If you try to quit the bloodshed and return to DOS, the program gives you advice such as "I wouldn’t leave if I were you. DOS is much worse." It also warns "Sit back with your milk and cookies and let the universe go to Hell — or act like a man! Slap a few shells into your shotgun and let’s kick some demonic butt."

While you’re chasing demons in Doom, the screen shows what your eyes see: your outstretched hand in front of you, holding your gun (or more bizzare weapons, such as chain saws), while a mirror on your wrist shows how bloodied your face got. The action is accompanied by a hard-pumping musical score, keeping your adrenaline up and punctuated by gunfire & ghoulish groans from all the monsters charging at you and being killed, hopefully! You and the monsters charge each other while running through corridors that close in on you faster than any nightmare.

Wolf 3-D wasn’t a true 3-D game, but at the time, it was the next best thing. The folks at Id placed 2-dimensional bitmaps on the framework of a wall in such a way that when you moved, the bitmaps would stretch and bend, making it look like your perspective had changed. Even the Nazis were just 2-dimensional bitmaps. You either saw their fronts or backs, but never their sides. Running a true 3-D game requires a powerful computer. Because it wasn’t truly 3-D, Wolf 3-D worked fine on a 286.

The most popular feature of Doom was the ability to play with (or against) up to 3 friends by modem or on a network. Doom was one of the first high-speed action games to offer that kind of play, which made it immensely popular.

Once again, Id shared their technology so other companies could make games like Doom. Many extra Doom levels were created, and some were even sold in stores.

In August 1996, Id released Quake, an almost entirely true 3-D sequel to Doom. In Quake, instead of using rectangular 2-dimensional bitmaps, Id used hundreds of polygons to make up each object or monster — so the game is extremely realistic and detailed but requires more RAM and a faster CPU (a Pentium or at least a 486DX4-100).

Id added a lot to Quake, which include swimming and fighting underwater, looking up and down, and fighting in reduced (and even zero) gravity. Multiplayer games can now include up to 8 players, and each player can choose which color pants and shirt his character will wear.

For more details about the development of Doom & Quake, see Philip Conrad’s article "Quake!" in the September 1996 issue of the Boston Computer Society’s PC Report magazine.

When the game begins, a demonstration plays on your screen until you press the Esc key. Select "New Game" or "Multiplayer" to play, or "Load Game" to resume a previously saved game.

Here are some hints:

Be careful when entering a new room: you may walk into a trap.

Don’t use the shotgun at long range: you won’t hurt anyone.

Don’t use grenades and rockets at point-blank range: you’ll hurt yourself.

Here are some Deathmatch hints:

Know your enemy: learn your opponents’ habits and hiding places.

Wear dark uniforms.

Beware of open spaces: stay near walls, and hide in shadows.

Keep moving: if you’re losing a fight, jump into the water to get away.

If you can sneak up on someone, get real close before you start shooting.

After killing an opponent, take his backpack for extra ammo.

ftp://ftp.idsoftware.com/idstuff/quake/

ftp://ftp2.idsoftware.com/idstuff/quake/

Beware: the shareware version is almost 8 megabytes. Downloading it takes about 2 hours with a 28.8-kilobaud modem, 3 hours with a 14.4-kilobaud modem.

You can also get shareware versions of Doom and its clones (except Descent and Dark Forces). Get them from your favorite bulletin-board system or online service.