Provided by: xletters_1.1.1-5.1build2_amd64 
NAME
xletters - catch falling words
SYNOPSIS
xletters [ options ]
DESCRIPTION
X Letters is a game under X to improve your typing skill. It is inspired by the game letters(6) by Larry
Moss and Brent Nordquist (which itself is inspired by the game Letter Invaders, and ultimately by the
famous Space Invaders).
The goal of the game is to destroy the words that fall down from the top before they reach the bottom.
To destroy a word, you must simply type it.
The game is organized in levels of increasing difficulty. Each level is divided into two parts: a normal
part and a bonus part. During the normal part, ordinary english words will fall down (found in the
system's dictionary, usually /usr/dict/words). During the bonus part, the words are randomly generated
from printable ascii characters.
If a word hits the ground during the normal part, you lose a life (you have five lives initially), and
the word disappears (but the others keep on falling). If a word hits the ground during the bonus part,
the bonus part simply ends, with no additional penalty, and the game proceeds to the next level.
The normal part of a level ends when a certain time has elapsed. The bonus part ends when either a
certain time has elapsed or when a word has hit the ground. The normal duration of a half-level is 600
time units, or 45 seconds (whatever the level).
Typing a word correctly makes the word disappear and scores you one point per letter, plus five more
points, plus another extra three points if the word was destroyed in the top fifth of the window. This
is the only way of gaining points: partially typed words are not worth anything, and even moving to
another level doesn't bring you points (this is because even if you don't type anything you will go
beyond the first level).
Short words fall faster than long ones. Unless otherwise specified at compile time, words are not
allowed to collide into one another. Therefore, when a new word appears, the game makes sure that all
the words below it fall at least as fast as it. The fall rate of the words also increases with the level
(it is, however, the same between the normal part and the bonus part of the same level). The rate at
which words appear is constant on a given level, but it increases with the level.
A word is considered typed when the last printable characters that you typed since the word appeared are
precisely the letters of the word. This means in particular that it is possible to ``kill two birds with
one stone'' if one word ends with the letters with which another one begins - in fact, if two identical
words appear (an unlikely but not impossible situation), you need only type one of them. To say things
differently, if you type a correct letter it will make your position in the word advance by one letter,
and if you type an incorrect letter, it will make your position move back to the last place in the word
that matches the characters you typed. The current position in each word is indicated by putting the
already typed letters in a different color (normally red). Note that a different behaviour is selectable
at compile time with which a wrong letter will cause all letters to be considered wrong (to make the
difference obvious, consider the word ``abracadabrx'': if after having typed ``abracadabr'' you press an
``a'', the normal behaviour will take you back to ``abra'' whereas the alternate behaviour will take you
back to the beginning).
The game keeps a high score table. When the game is over, one way or another, xletters will show, for
the user and for the twenty best players, the name, the level reached, the final score, and the time
during which the game was running. Normally, each player is allowed only one entry in the high score
table. This can be modified at compilation time, however.
CONTROLS
The top of the window shows three buttons. The Quit button will take you out of the game, the Pause
button will pause the game or resume it if it was already paused, and the Next button will move to the
next level (normal part). These buttons can also be accessed through accelerators: the ``Escape'' key
will quit the game, the ``Tab'' key (or ``Pause'' if you have one) will suspend it or resume it, and the
``Page Down'' key (or ``Next'' if it is so labeled) will advance one level.
Three labels on the right of the buttons are used to indicate your lives, score and current level.
Other than that, to play the game you must simply type the words. In order for the typing to be
effective, your mouse cursor must be in the game space (the large square area below the buttons and
labels). If you start typing while the game is paused, it will automatically resume.
Scoring is made much more complicated if you choose to use the Next button to warp through levels. (The
point is that it should be used to avoid having to go through all the easy levels if you already type
very fast. So it should not handicap you excessively by giving you no points which you would have gotten
if you had worked your way through those levels. On the other hand, it should not be an obvious way of
gaining arbitrarily many points.) Here is the way it works: when you use the Next button to warp to the
next level, you gain 350 ``virtual'' points. Those points are indicated in parentheses after your real
points in the score label. They are not worth anything by themselves. On the other hand, if you have
virtual points, every time you gain some points, that many virtual points will also be converted to real
points (until you no longer have virtual points). Thus, virtual points are worth something only if you
prove yourself good enough to make them so.
There are some restrictions to the use of the Next button. First, it will only work in the bonus part of
a level, or if no word has fallen lower than the top fifth of the screen. This is so you can't use it to
get yourself easily out of a tricky situation. Second, if you already scored some points on the current
level, using the Next button will award you fewer than the normal 350 virtual points (see above), in fact
precisely twice fewer than as many points as you gained on the level (but no less than zero, of course).
TRAINING MODE
xletters has a training mode, which you can invoke using the -train command line option. In training
mode, only one (english) word appears at a time, anywhere on the game space, and it does not fall. A new
word appears as soon as you finish typing the previous one. In training mode, there are no lives,
points, levels, or bonus words.
DEATHMATCH AND DUEL
xletters also has the amazing ``deathmatch'' mode. To invoke this mode, use the -death command line
option. This has the following effects on the behaviour of xletters: first, it will read words on the
standard input, and make them fall. Second, you can choose between typing falling words, or typing a
special word in a special part of the display, just above the game space. To switch between both modes,
use the Mode button or press the ``Backspace'' key. The special word typed must be an english word: if
the letter you type makes the word fragment no longer begin a word in the dictionary, it immediately
disappears. When you type a full word, you can then send it by using the Send button or by pressing the
``Return'' key. The word sent gets printed on the standard output.
These features make sense when two copies of xletters are run in deathmatch mode, with the standard
output of each being sent to the standard input of the other (possibly across the network). Then the
player on each game can not only kill his falling words but also send words to the other player.
Even more extreme than the ``deathmatch'' mode is the ``duel'' mode, activated through the -duel command
switch. In duel mode, the computer does not send words of its own, and only words sent through the
standard input will appear. In this case, there is no Next button, and switching to the next level can
only occur after a certain amount of time. In fact, there are no bonus parts of levels, so levels change
twice more rapidly than in normal play. Moreover, a level change does not erase all the current words
contrary to what happens in normal (or deathmatch) mode.
The X Letters distribution includes a shell script named xletters-duel which uses Avian Research's netcat
program (nc) to open a socket, run xletters in duel mode, and try to connect to the same socket on a
given computer. Thus, two people on two different computers can play a duel by each running xletters-
duel with the name of the other's computer as parameter. (Both copies must be run within five seconds of
the other.)
OPTIONS
X Letters recognizes all the standard X Toolkit command line options, among which the following:
-bg color
Specifies the background color to use.
-fg color
Specifies the foreground color to use for the labels and buttons.
-fn font
Specifies the font to use for displaying the labels and buttons.
-name name
Specifies the application name under which resources are to be obtained, rather than under the
default executable file name. name should not contain ``.'' or ``*'' characters.
-title string
Specifies the window title string.
-geometry geometry
Specifies the preferred position of the window. Specifying a size is not recommended.
-display display
Specifies the X server to use.
-xrm resourcestring
Explicitely give a resource string.
The following additional options are recognized by xletters:
-wfn font
Specifies the font to use for the falling words. (Sets the wordFont resource.)
-wc color
Specifies which color to use for the words. (Sets the wordColor resource.)
-tc color
Specifies which color to use for the correctly typed part of the words. (Sets the typedColor
resource.)
-gbg color
Specifies which color to use for the background of the game space. (Sets the gameSpace.background
resource.)
-notrain
Do not go in training mode (this is the default). (Sets the trainingMode resource to ``False''.)
-train Run the game in training mode (see TRAINING MODE above). (Sets the trainingMode resource to
``True''.)
-nodeath
Do not run in deathmatch or duel mode (this is the default). (Sets the deathMode resource to
``normal''.)
-death Run in deathmatch mode (see DEATHMATCH AND DUEL above). (Sets the deathMode resource to
``death''.)
-duel Run in duel mode (see DEATHMATCH AND DUEL above). (Sets the deathMode resource to ``duel''.)
In addition, xletters recognizes -help and -version options.
WIDGETS
groundBox (class Box, parent (toplevel))
This is the main application box that supports all the other widgets.
label (class Label, parent groundBox)
The xletters label. The text of this label cannot be changed.
quitButton (class Command, parent groundBox)
The Quit button.
pauseButton (class Toggle, parent groundBox)
The Pause button.
livesLabel (class Label, parent groundBox)
The lives label.
scoreLabel (class Label, parent groundBox)
The score label.
levelLabel (class Label, parent groundBox)
The level label.
gameSpace (class Core, parent groundBox)
The game space in which the words fall. Key presses and Expose events are handled through event
handlers and not the ordinary translation/action mechanism.
RESOURCES
In addition to the resources of the various widgets, the xletters application itself recognizes some
resources. These are:
wordFont (class Font, type FontStruct)
The font in which the falling words are written.
wordColor (class Foreground, type Pixel)
The color in which the (untyped part of the) falling words are written.
typedColor (class HighlightColor, type Pixel)
The color in which the typed part of the falling words are written.
deathMode (class DeathMode, type String)
Either normal, death or duel according as the game should be run in normal, deathmatch or duel
mode (see DEATHMATCH AND DUEL above).
trainingMode (class TrainingMode, type Boolean)
Whether the game should be run in training mode (this overrides any value of the deathMode
resource (see TRAINING MODE above).
FILES
(If not overriden at compile time)
/usr/share/dict/words
The dictionary of words.
/var/games/xletters/scores
The high score table.
CONFIGURATION SUGGESTION
xletters -wfn '-bitstream-terminal-medium-r-normal--18-*-*-*-c-*-iso8859-1' -gbg 'MidnightBlue' -wc
'PaleGoldenrod' -tc 'Orchid'
BUGS
None known. Surely a very temporary situation :-)
This is one of the ugliest programs I ever wrote. I would not be surprized to discover plenty of bugs in
it. Version 1.0.0 was ugly enough. Version 1.1.0 gave a whole new meaning to the word ``uglyfication''.
SECURITY
xletters wants to access a high score table. If this score table is to be shared between several users,
xletters will probably be made sgid games or some such thing. Beware that it is probably very easy to
fool (or even brake to pieces). I have no doubt that running it against a fake X server (and probably
other similar things) can give not-too-hard access to whatever permissions it has been given.
Consequently, it should not be given any critical permissions.
AUTHORS
Peter Horvai (peter.horvai@ens.fr) wrote the deathmatch feature and implemented mmap()ing the dictionary
file.
David Madore (david.madore@ens.fr) wrote version 1.0.0, all the X Windows parts of the game, and this man
page.
COPYING
GNU public license. See the file COPYING for more information.
SEE ALSO
letters(6), xtetris(6)
05 NOV 1998 XLETTERS(6)