traffic controller game
lets you try your hand at the nerve wracking
duties of the air traffic controller without endangering the lives of millions
of travelers each year. Your responsibilities require you to direct the flight
of jets and prop planes into and out of the flight arena and airports. The
speed (update time) and frequency of the planes depend on the difficulty of
the chosen arena.
- Print the usage line and exit.
- Same as -u.
- Print a list of available games and exit. The first game
name printed is the default game.
- Print the score list (formerly the Top Ten list).
- Same as -s.
- Print the path to the special directory where
atc expects to find its private files. This
is used during the installation of the program.
- Play the named game. If the game listed is not one of the
ones printed from the -l option, the default
game is played.
- Same as -g.
- Set the random seed. The purpose of this flag is
Your goal in atc
is to keep the game going as long
as possible. There is no winning state, except to beat the times of other
players. You will need to: launch planes at airports (by instructing them to
increase their altitude); land planes at airports (by instructing them to go
to altitude zero when exactly over the airport); and maneuver planes out of
Several things will cause the end of the game. Each plane has a destination (see
information area), and sending a plane to the wrong destination is an error.
Planes can run out of fuel, or can collide. Collision is defined as adjacency
in all three dimensions. A plane leaving the arena in any other way than
through its destination exit is an error as well.
Scores are sorted in order of the number of planes safe. The other statistics
are provided merely for fun. There is no penalty for taking longer than
another player (except in the case of ties).
Suspending a game is not permitted. If you get a talk message, tough. When was
the last time an Air Traffic Controller got called away to the phone?
Depending on the terminal you run atc
screen will be divided into 4 areas. It should be stressed that the terminal
driver portion of the game was designed to be reconfigurable, so the display
format can vary depending on the version you are playing. The descriptions
here are based on the ascii version of the game. The game rules and input
format, however, should remain consistent. Control-L redraws the screen,
should it become muddled.
The first screen area is the radar display, showing the relative locations of
the planes, airports, standard entry/exit points, radar beacons, and ``lines''
which simply serve to aid you in guiding the planes.
Planes are shown as a single letter with an altitude. If the numerical altitude
is a single digit, then it represents thousands of feet. Some distinction is
made between the prop planes and the jets. On ascii terminals, prop planes are
represented by a upper case letter, jets by a lower case letter.
Airports are shown as a number and some indication of the direction planes must
be going to land at the airport. On ascii terminals, this is one of `^',
`>', `<', and `v', to indicate north (0 degrees), east (90), west (270)
and south (180), respectively. The planes will also take off in this
Beacons are represented as circles or asterisks and a number. Their purpose is
to offer a place of easy reference to the plane pilots. See
THE DELAY COMMAND
Entry/exit points are displayed as numbers along the border of the radar screen.
Planes will enter the arena from these points without warning. These points
have a direction associated with them, and planes will always enter the arena
from this direction. On the ascii version of atc
this direction is not displayed. It will become apparent what this direction
is as the game progresses.
Incoming planes will always enter at the same altitude: 7000 feet. For a plane
to successfully depart through an entry/exit point, it must be flying at 9000
feet. It is not necessary for the planes to be flying in any particular
direction when they leave the arena (yet).
The second area of the display is the information area, which lists the time
(number of updates since start), and the number of planes you have directed
safely out of the arena. Below this is a list of planes currently in the air,
followed by a blank line, and then a list of planes on the ground (at
airports). Each line lists the plane name and its current altitude, an
optional asterisk indicating low fuel, the plane's destination, and the
plane's current command. Changing altitude is not considered to be a command
and is therefore not displayed. The following are some possible information
B4*A0: Circle @ b1
g7 E4: 225
The first example shows a prop plane named `B' that is flying at 4000 feet. It
is low on fuel (note the `*'). Its destination is Airport #0. The next command
it expects to do is circle when it reaches Beacon #1. The second example shows
a jet named `g' at 7000 feet, destined for Exit #4. It is just now executing a
turn to 225 degrees (South-West).
The third area of the display is the input area. It is here that your input is
reflected. See the INPUT
this manual for more details.
This area is used simply to give credit where credit is due. :-)
A command completion interface is built into the game. At any time, typing `?'
will list possible input characters. Typing a backspace (your erase character)
backs up, erasing the last part of the command. When a command is complete, a
return enters it, and any semantic checking is done at that time. If no errors
are detected, the command is sent to the appropriate plane. If an error is
discovered during the check, the offending statement will be underscored and a
(hopefully) descriptive message will be printed under it.
The command syntax is broken into two parts: Immediate
commands happen on the next
commands also happen on the
next update unless they are followed by an optional predicate called the
In the following tables, the syntax [0-9]
single digit, and ⟨dir
⟩ refers to a
direction, given by the keys around the `s' key: ``wedcxzaq''. In absolute
references, `q' refers to North-West or 315 degrees, and `w' refers to North,
or 0 degrees. In relative references, `q' refers to -45 degrees or 45 degrees
left, and `w' refers to 0 degrees, or no change in direction.
All commands start with a plane letter. This indicates the recipient of the
command. Case is ignored.
- a [ cd+- ]
- Altitude: Change a plane's altitude, possibly requesting
takeoff. `+' and `-' are the same as `c' and `d'.
- Climb or descend to the given altitude (in thousands of
- Climb: relative altitude change.
- Descend: relative altitude change.
- Mark: Display in highlighted mode. Plane and command
information is displayed normally.
- Ignore: Do not display highlighted. Command is displayed as
a line of dashes if there is no command.
- Unmark: Same as ignore, but if a delayed command is
processed, the plane will become marked. This is useful if you want to
forget about a plane during part, but not all, of its journey.
- c [ lr ]
- Circle: Have the plane circle.
- Left: Circle counterclockwise.
- Right: Circle clockwise (default).
- t [ l-r+LR ] [ dir ] or tt [
abe* ] number
- Turn: Change direction.
- Turn to direction: Turn to the absolute compass heading
given. The shortest turn will be taken.
- tl [ dir ]
- Left: Turn counterclockwise: 45 degrees by default, or
the amount specified in ⟨dir⟩ (not
to ⟨dir⟩.) `w' (0 degrees)
is no turn. `e' is 45 degrees; `q' gives -45 degrees counterclockwise,
that is, 45 degrees clockwise.
- t- [ dir ]
- Same as left.
- tr [ dir ]
- Right: Turn clockwise, 45 degrees by default, or the
amount specified in ⟨dir⟩.
- t+ [ dir ]
- Same as right.
- Hard left: Turn counterclockwise 90 degrees.
- Hard right: Turn clockwise 90 degrees.
- tt [abe*]
- Towards: Turn towards a beacon, airport or exit. The
turn is just an estimate.
- Turn towards the given airport.
- Turn towards the specified beacon.
- Turn towards an exit.
- Same as ttb.
(a/@) command may be appended to any
command. It allows the controller to
instruct a plane to do an action when the plane reaches a particular beacon
(or other objects in future versions).
- Do the delayable command when the plane reaches the
specified beacon. The `b' for ``beacon'' is redundant to allow for
expansion. `@' can be used instead of `a'.
Planes are marked
by default when they enter the
arena. This means they are displayed in highlighted mode on the radar display.
A plane may also be either unmarked
. An ignored
plane is drawn in unhighlighted mode, and a line of dashes is displayed in the
command field of the information area. The plane will remain this way until a
mark command has been issued. Any other command will be issued, but the
command line will return to a line of dashes when the command is completed.
plane is treated the same as an
plane, except that it will automatically
switch to marked
status when a delayed command
has been processed. This is useful if you want to forget about a plane for a
while, but its flight path has not yet been completely set.
As with all of the commands, marking, unmarking and ignoring will take effect at
the beginning of the next update. Do not be surprised if the plane does not
immediately switch to unhighlighted mode.
- Plane A: turn left at beacon #1
- Plane C: circle
- Plane G: turn towards exit #4 at beacon #2
- Plane M: altitude: climb 2000 feet
- Plane S: turn to 315
- Plane X: ignore
- Jets move every update; prop planes move every other
- All planes turn at most 90 degrees per movement.
- Planes enter at 7000 feet and leave at 9000 feet.
- Planes flying at an altitude of 0 crash if they are not
over an airport.
- Planes waiting at airports can only be told to take off
(climb in altitude).
- Pressing return (that is, entering an empty command)
will perform the next update immediately. This allows you to ``fast
forward'' the game clock if nothing interesting is happening.
file lists the currently available
play fields. New field description file names must be placed in this file to
be playable. If a player specifies a game not in this file, his score will not
The game field description files are broken into two parts. The first part is
the definition section. Here, the four tunable game parameters must be set.
These variables are set with the syntax:
variable = number;
Variable may be one of:
, indicating the number of
seconds between forced updates;
(about) the number of updates between new plane entries;
, indicating the width of the play field; or
, indicating the height of the play field.
The second part of the field description files describes the locations of the
exits, the beacons, the airports and the lines. The syntax is as follows:
- (x y) ... ;
- (x y direction) ... ;
- (x y direction) ... ;
- [ (x1 y1) (x2 y2) ] ... ;
For beacons, a simple x, y coordinate pair is used (enclosed in parenthesis).
Airports and exits require a third value, which is one of the directions
. For airports, this is the direction
that planes must be going to take off and land, and for exits, this is the
direction that planes will be going when they
the arena. This may not seem intuitive, but
as there is no restriction on direction of exit, this is appropriate. Lines
are slightly different, since they need two coordinate pairs to specify the
line endpoints. These endpoints must be enclosed in square brackets.
All statements are semi-colon (;) terminated. Multiple item statements
accumulate. Each definition must occur exactly once, before any item
statements. Comments begin with a hash (#) symbol and terminate with a
newline. The coordinates are between zero and width-1 and height-1 inclusive.
All of the exit coordinates must lie on the borders, and all of the beacons
and airports must lie inside of the borders. Line endpoints may be anywhere
within the field, so long as the lines are horizontal, vertical or
# This is the default game.
update = 5;
newplane = 5;
width = 30;
height = 21;
exit: ( 12 0 x ) ( 29 0 z ) ( 29 7 a ) ( 29 17 a )
( 9 20 e ) ( 0 13 d ) ( 0 7 d ) ( 0 0 c ) ;
beacon: ( 12 7 ) ( 12 17 ) ;
airport: ( 20 15 w ) ( 20 18 d ) ;
line: [ ( 1 1 ) ( 6 6 ) ]
[ ( 12 1 ) ( 12 6 ) ]
[ ( 13 7 ) ( 28 7 ) ]
[ ( 28 1 ) ( 13 16 ) ]
[ ( 1 13 ) ( 11 13 ) ]
[ ( 12 8 ) ( 12 16 ) ]
[ ( 11 18 ) ( 10 19 ) ]
[ ( 13 17 ) ( 28 17 ) ]
[ ( 1 7 ) ( 11 7 ) ] ;
Files are kept in a special directory. See the
section for a way to
print this path out. It is normally
This directory contains the file Game_List
holds the list of playable games, as well as the games themselves.
The scores are kept in
Ed James, UC Berkeley: email@example.com, ucbvax!edjames
This game is based on someone's description of the overall flavor of a game
written for some unknown PC many years ago, maybe.
The screen sometimes refreshes after you have quit.