ATC(6)                        NetBSD Games Manual                       ATC(6)

NAME
     atc -- air traffic controller game

SYNOPSIS
     atc [-u?lstp] [-gf game name] [-r random seed]

DESCRIPTION
     atc lets you try your hand at the nerve wracking duties of the air traf-
     fic 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.

OPTIONS
     -u    Print the usage line and exit.

     -?    Same as -u.

     -l    Print a list of available games and exit.  The first game name
           printed is the default game.

     -s    Print the score list (formerly the Top Ten list).

     -t    Same as -s.

     -p    Print the path to the special directory where atc expects to find
           its private files.  This is used during the installation of the
           program.

     -g game
           Play the named game.  If the game listed is not one of the ones
           printed from the -l option, the default game is played.

     -f game
           Same as -g.

     -r seed
           Set the random seed.  The purpose of this flag is questionable.

GOALS
     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 exit
     points.

     Several things will cause the end of the game.  Each plane has a destina-
     tion (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 sta-
     tistics 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?

THE DISPLAY
     Depending on the terminal you run atc on, the 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.

   RADAR
     The first screen area is the radar display, showing the relative loca-
     tions 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 ter-
     minals, 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 direction.

     Beacons are represented as circles or asterisks and a number.  Their pur-
     pose is to offer a place of easy reference to the plane pilots.  See THE
     DELAY COMMAND section below.

     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 fly-
     ing at 9000 feet.  It is not necessary for the planes to be flying in any
     particular direction when they leave the arena (yet).

   INFORMATION AREA
     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 cur-
     rently 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 destina-
     tion, and the plane's current command.  Changing altitude is not consid-
     ered to be a command and is therefore not displayed.  The following are
     some possible information lines:

           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).

   INPUT AREA
     The third area of the display is the input area.  It is here that your
     input is reflected.  See the INPUT heading of this manual for more
     details.

   AUTHOR AREA
     This area is used simply to give credit where credit is due. :-)

INPUT
     A command completion interface is built into the game.  At any time, typ-
     ing `?' 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 Only and Delayable
     commands.  Immediate Only commands happen on the next update.  Delayable
     commands also happen on the next update unless they are followed by an
     optional predicate called the Delay command.

     In the following tables, the syntax [0-9] means any single digit, and
     <dir> refers to a direction, given by the keys around the `s' key: ``wed-
     cxzaq''.  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.

   IMMEDIATE ONLY COMMANDS
     a [ cd+- ] number
           Altitude: Change a plane's altitude, possibly requesting takeoff.
           `+' and `-' are the same as `c' and `d'.
           a number    Climb or descend to the given altitude (in thousands of
                       feet).
           ac number   Climb: relative altitude change.
           ad number   Descend: relative altitude change.

     m     Mark: Display in highlighted mode.  Plane and command information
           is displayed normally.

     i     Ignore: Do not display highlighted.  Command is displayed as a line
           of dashes if there is no command.

     u     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.

   DELAYABLE COMMANDS
     c [ lr ]
           Circle: Have the plane circle.
           cl          Left: Circle counterclockwise.
           cr          Right: Circle clockwise (default).

     t [ l-r+LR ] [ dir ] or tt [ abe* ] number
           Turn: Change direction.
           t<dir>      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 clock-
                       wise.
           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.
           tL          Hard left: Turn counterclockwise 90 degrees.
           tR          Hard right: Turn clockwise 90 degrees.
           tt [abe*]   Towards: Turn towards a beacon, airport or exit.  The
                       turn is just an estimate.
           tta number  Turn towards the given airport.
           ttb number  Turn towards the specified beacon.
           tte number  Turn towards an exit.
           tt* number  Same as ttb.

   THE DELAY COMMAND
     The Delay (a/@) command may be appended to any Delayable 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).

     ab number
           Do the delayable command when the plane reaches the specified bea-
           con.  The `b' for ``beacon'' is redundant to allow for expansion.
           `@' can be used instead of `a'.

   MARKING, UNMARKING AND IGNORING
     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 or ignored.  An ignored plane is drawn in unhigh-
     lighted 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 com-
     mand 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.

     An unmarked plane is treated the same as an ignored 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.

   EXAMPLES
           atlab1    Plane A: turn left at beacon #1

           cc        Plane C: circle

           gtte4ab2  Plane G: turn towards exit #4 at beacon #2

           ma+2      Plane M: altitude: climb 2000 feet

           stq       Plane S: turn to 315

           xi        Plane X: ignore

OTHER INFORMATION
     o   Jets move every update; prop planes move every other update.

     o   All planes turn at most 90 degrees per movement.

     o   Planes enter at 7000 feet and leave at 9000 feet.

     o   Planes flying at an altitude of 0 crash if they are not over an air-
         port.

     o   Planes waiting at airports can only be told to take off (climb in
         altitude).

     o   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.

NEW GAMES
     The Game_List 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 be logged.

     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: update, indicating the number of seconds between
     forced updates; newplane, indicating (about) the number of updates
     between new plane entries; width, indicating the width of the play field;
     or height, 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:

           beacon:   (x y) ... ;
           airport:  (x y direction) ... ;
           exit:     (x y direction) ... ;
           line:     [ (x1 y1) (x2 y2) ] ... ;

     For beacons, a simple x, y coordinate pair is used (enclosed in parenthe-
     sis).  Airports and exits require a third value, which is one of the
     directions wedcxzaq.  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 enter 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 coordi-
     nate 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 end-
     points may be anywhere within the field, so long as the lines are hori-
     zontal, vertical or exactly diagonal.

   FIELD FILE EXAMPLE
     # 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
     Files are kept in a special directory.  See the OPTIONS section for a way
     to print this path out.  It is normally /usr/share/games/atc.

     This directory contains the file Game_List, which holds the list of
     playable games, as well as the games themselves.

     The scores are kept in /var/games/atc_score.

AUTHORS
     Ed James, UC Berkeley: edjames@ucbvax.berkeley.edu, 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.

BUGS
     The screen sometimes refreshes after you have quit.

NetBSD 5.0_STABLE               January 1, 2004              NetBSD 5.0_STABLE
