Provided by: tworld_1.3.2-3_amd64 
NAME
tworld - Tile World
SYNOPSIS
Tile World is a reimplementation of the game "Chip's Challenge". The player controls Chip, navigating him
through his challenges. The object of each level of the game is to find and reach the exit tile, which
takes you to the next level. The levels contain many different kinds of obstacles, creatures both hostile
and indifferent, tools, protective gear -- and, of course, chips.
OVERVIEW OF THE GAME
The main display shows Chip in the current level and his immediate surroundings. To the right of this
display is shown the basic information about the current level. The most important data shown here are
how many seconds are left on the clock, and how many chips still need to be collected. (On some level the
clock does not show a time. These levels have no time limit.)
The object of every level is to find and reach the exit before the time runs out. The exit is frequently
(but not always) guarded by a chip socket. To move past the chip socket, Chip must collect a certain
number of computer chips; the amount needed is different in each level. As you play a level, the
information display on the right shows the number of chips that still need to be collected in order to
open the socket. (Remember that getting enough chips to open the chip socket is only a subgoal, not the
main goal. Some levels do not require any chips to be collected; some levels have no chip socket at all.)
Also occupying many of the levels are other creatures. Most (but not all) of them move about in simple,
predictable patterns, and without regard for Chip's presence. The creatures know enough to avoid running
into each other, but a collision with Chip is fatal. The complete taxonomy of creatures is: tanks, balls,
gliders, fireballs, walkers, blobs, teeth, bugs, and paramecia.
In addition to the socket and the main exit, there are also four different kinds of doors. These doors
can be opened with the right kind of key. The doors and the keys are color-coded -- red, green, blue, and
yellow -- so you can tell them apart. Like the chip socket, a door that has been opened stays open. Keys
are picked up simply by stepping upon them. The key disappears from the map and appears in your
possession. Keys in your possession are displayed on the right-hand side of the window.
Besides keys and chips, there are also four kinds of special footgear that Chip can collect. Like keys,
boots can be picked up simply by walking over them. (There is no limit to the number of boots you can
have.) These boots permit Chip to walk across four different kinds of surfaces, just as if they were
normal flooring. Fire and water are two kind of tiles that are normally fatal to Chip, but fire boots and
water boots will permit safe passage across these. Stepping onto ice sends Chip sliding at high speed
unless he has a pair of ice boots. Finally, there are force floors that push Chip along in a specific
direction; these can be counteracted with force boots.
Two other types of surfaces are more useful to Chip, in that they keep other creatures out. These are
dirt and gravel, and they are special in that Chip is the only one who can walk on them. However, when
Chip steps onto a dirt tile, it is cleared away and becomes normal flooring. Gravel, on the other hand,
is permanent.
There are numerous other objects scattered around the various levels, which Chip can interact with,
although he cannot pick them up. Bombs are one kind of object which should always be avoided, as they
explode when stepped on. The thief tile should also generally be avoided; entering this tile will cause
Chip to lose any footgear he has collected.
Dirt blocks are large, movable squares of dirt. Chip can push them about, and use them to wall off areas
or to safely detonate bombs. Furthermore, if a block is pushed into water, the tile will turn into dirt
(which will become normal flooring when Chip steps on it). Finally, note that blocks can sometimes be
resting on top of other objects, both helpful (such as a key) and harmful (such as a bomb).
Some levels have teleports. Entering a teleport causes Chip to vanish and instantaneously reappear at
another teleport.
Even some of the walls can demonstrate surprising behavior. The so-called blue walls can either be actual
walls, or empty mirages. The only way for Chip to tell which is which is to attempt to walk through one.
There are also popup walls -- Chip can walk across these only once, for they turn into walls as he walks
over them.
There are four different types of pushbuttons. Like keys and boots, they are color-coded. Stepping on a
pushbutton activates it.
The green buttons control the toggle walls. Toggle walls have dotted green outlines, and they change
between being open (passable, like any other floor) and open (unpassable, a wall). When a green button is
pressed, the closed toggle walls are opened and the open toggle walls are closed.
Brown buttons control bear traps. Anything that wanders into a bear trap will be stuck there until the
brown button connected to it is pushed.
Blue buttons exercise some control over the tanks. Normally, a tank moves directly forward until it hits
an obstacle, whereupon it stops. But when a blue button is pressed, all tanks turn around 180 degrees
and begin moving again.
The objects with the most potential for help and hindrance are the clone machines, which are controlled
by red buttons. Every clone machine contains a dirt block, a tank, or some other creature. When the clone
machine's red button is pressed, a duplicate of whatever the clone machine contains is created and set
loose.
Once in a while there will also be hint buttons. These have a question mark displayed on them. When Chip
steps onto a hint button, a short bit of information will be displayed in the lower right-hand area of
the window.
Here are some general hints for successful play:
* When moving dirt blocks around, take care not to shove them into corners where you can't get them out
again.
* On some of the more mazelike levels, you may need to sketch out a map in order to solve it.
* Many of the creatures move in specific patterns (for example, as with the tanks mentioned above).
* A number of the objects in the game will affect other creatures in the same way they affect Chip.
* Remember that if you get trapped somewhere, you can always use Ctrl-R to restart a level.
* When you find a level to be unusually difficult, take some time to examine it carefully. Make sure you
truly know what options are available to you. In any case, keep trying. Occasionally the game will give
you the opportunity to skip a level that seems too hard.
PASSWORDS
Every level has a four-letter password. The password for a level is shown in the information display at
the upper-right of the window. The ostensible purpose of passwords is to allow you to come back to a
level. However, normally you will never need to remember passwords, as Tile World will automatically
store the passwords for you. However, if you somehow manage to learn the password of a level that you
have yet to achieve, you can use the password to gain early access to that level.
SCORING
For each level in a set that you complete, the game awards 500 points times the level's number.
Furthermore, if the level is timed, an extra 10 points is added for every second left on the clock when
you finish the level. You can thus sometimes improve your score by returning to already-completed levels
and playing them again.
KEY COMMANDS
During game play, the arrows are the most important keys; they move Chip through the level. The keys 2 4
6 8 on the numeric keypad can also be used for the same purpose. Other keys have the following functions:
Bkspc pauses the game; press any key to resume play.
Ctrl-H same as Bkspc.
Ctrl-N stops the current game and moves forward to the next level.
Ctrl-P stops the current game and moves back to the previous level.
Q quits the current level.
Ctrl-R starts over at the beginning of the current level.
? pauses the game and displays a list of topics for which help is available within the program.
V decreases the volume level. (If the volume level is reduced to zero, then the program will display
sound effects textually, as onomatopoeia.)
Shift-V
increases the volume level.
At the start of a level, before game play begins, the following key commands are available:
Q returns to the list of available level sets.
Spc starts the current level without moving (i.e., standing still).
N moves to the next level.
P moves to the previous level.
PgUp moves ahead ten levels.
PgDn moves back ten levels.
G displays a prompt and accepts a password, then jumps to the level with that password.
Tab plays back the best solution for that level.
Shift-Tab
verifies the best solution for that level. If the solution is no longer valid (e.g. because the
level has been altered), the solution will automatically be deprecated.
Ctrl-I same as Tab.
Shift-Ctrl-I
same as Shift-Tab.
O toggles between even-step and odd-step offset.
Shift-O
(Lynx-mode only) increments the stepping offset by one.
F (Lynx-mode only) rotates the initial "random" force floor direction.
Ctrl-X deprecates the best solution for that level. If the level is then successfully completed again,
the saved solution will be replaced with the new one, whether or not it had a better time.
Shift-Ctrl-X
deletes the saved solution for that level. If confirmed, the solution will be immediately removed
from the solution file.
S displays the list of known levels and the score for each, as well as the overall score for the
level set. The score list display also permits changing the current level by moving the selection
and pressing Enter.
Ctrl-S displays the list of solution files in the save directory whose names start with the name of the
current level set. From here a different solution file can be selected.
? displays a list of topics for which help is available within the program.
At every point in the program, the Q key will abort the current activity and return to the previous
display.
Finally, the program can be exited at any time by pressing Shift-Q. (Ctrl-C or Alt-F4 will also force an
immediate exit.)
RULESETS
Tile World contains emulators for two different versions of "Chip's Challenge". They are referred to as
the Lynx ruleset and the MS ruleset. The Lynx ruleset recreates the original implementation of the game,
and the MS ruleset recreates the version that was implemented for Microsoft Windows (cf HISTORY).
The most notable difference between the two rulesets is that in the MS ruleset, movement between tiles is
instantaneous, whereas under the Lynx ruleset motion occurs across several "ticks". (This probably
reflects the fact that the latter ran on dedicated hardware, while the former ran on 33 MHz PCs under a
non-preemptive multitasking OS.) Although the basic mechanics of the game are the same under both
rulesets, there are also a host of subtle differences between the two.
Each level set file includes a flag that indicates which ruleset it is to be played under. Some level
sets can be played under both rulesets (most notably, the original set of levels), but this is the
exception.
ADDING NEW LEVEL SETS
Level sets are defined by data files. By convention these file are named with a .dat extension. Typically
the name proper contains the author's first name, last initial, and a single digit -- for example,
EricS1.dat. (The digit is used to give the sequence in case the author, for whatever reason, stores their
creations in more than one file.)
When a new data file is obtained, it may simply be copied into the level set directory (cf DIRECTORIES),
and Tile World will then make it available for playing.
An alternate method is to use a configuration file (see CONFIGURATION FILES below).
COMMAND-LINE OPTIONS
tworld is normally invoked without arguments. The program begins by displaying a list of the available
level sets. After a level set is chosen, the program jumps to the first unsolved level to begin play.
The available command-line options are enumerated in the following table. (Windows users: The options
that cause the program to display information on standard output actually go to a file named stdout.txt
instead.)
-a, --audio-buffer=N
Set the size of the audio buffer. N can be a value from 1 (the default) to 6. Each higher value
doubles the amount of buffering. This option can reduce static or distortion in the sound
playback, at the cost of increased latency.
-b, --batch-verify
Do a batch-mode verification of the existing solutions and exit. Levels with invalid solutions
are displayed on standard output. If used with -q, then nothing is displayed, and the program's
exit code is the number of invalid solutions. Can also be used with -s or -t to have solutions
verified before the other option is applied. Note that this options requires a level set file
and/or a solution file be named on the command line.
-D, --data-dir=DIR
Read level data files from DIR instead of the default directory.
-d, --list-dirs
Display the default directories used by the program on standard output, and exit.
-F, --full-screen
Run in full-screen mode.
--histogram
Upon exit, display a histogram of idle time on standard output. (This option is used for
evaluating optimization efforts.)
-h, --help
Display a summary of the command-line syntax on standard output and exit.
-L, --levelset-dir=DIR
Load level sets from DIR instead of the default directory.
-l, --list-levelsets
Write a list of available level sets to standard output and exit.
-n, --volume=N
Set the initial volume level to N, 0 being silence and 10 being full volume. The default level is
10.
-P, --pedantic
Turn on pedantic mode, forcing the Lynx ruleset to emulate the original game as closely as
possible. (See the Tile World website for more information on emulation of the Lynx ruleset.)
-p, --no-passwords
Turn off all password-checking. This option allows the normal sequence of levels to be bypassed.
-q, --quiet
Run quietly. All sounds, including the ringing of the system bell, are suppressed.
-r, --read-only
Run in read-only mode. This guarantees that no changes will be made to the solution files.
-R, --resource-dir=DIR
Read resource data from DIR instead of the default directory.
-S, --save-dir=DIR
Read and write solution files under DIR instead of the default directory.
-s, --list-scores
Display the current scores for the selected level set on standard output and exit. A level set
must be named on the command line. If used with -b, the solutions are verified beforehand, and
invalid solutions are indicated.
-t, --list-times
Display the best times for the selected level set on standard output and exit. A level set must be
named on the command line. If used with --batch-verify, the solutions are verified beforehand, and
invalid solutions are indicated.
-V, --version
Display the program's version and license information on standard output and exit.
-v, --version-number
Display the program's version number on standard output and exit.
Besides the above options, tworld can accept up to three command-line arguments: the name of a level set,
the number of a level to start on, and the name of an alternate solution file. If the name of an
installed level set is specified, then Tile World will start up in that set, skipping the initial level
set selection.
If the specified level set is not a simple name but is a pathname (relative or absolute), then Tile World
will use that level set only, without requiring that it first be installed. No solutions will be saved
unless an explicit solution file is also supplied on the command-line. (If the command-line only
specifies a solution file, then Tile World will look up the name of the level set in the solution file.)
CONFIGURATION FILES
Configuration files are used to override some of the settings in a data file, or to set values not
provided for by the data file format. Configuration files are by convention named with a .dac extension.
A configuration file is stored in the level set directory in the place of the data file, which then goes
into the data directory (cf DIRECTORIES).
The configuration file is a simple text file. The first line of a configuration file must have the
following form:
file = DATAFILE
where DATAFILE is the filename of the data file. (Arbitrary whitespace is permitted around the equal
sign, but there cannot be any whitespace embedded at the beginning of the line.) After this initial line,
the configuration file can contain any of the following lines:
usepasswords = y|n
This line permits password-checking to be enabled/disabled when playing the levels in the set. The
default is y.
messages = TEXTFILE
This line specifies a messages file to provide short textual messages to be displayed in between levels
during play. TEXTFILE names a file located in the data directory.
ruleset = ms|lynx
This line allows the configuration file to override the ruleset setting in the data file. This is mainly
useful in the case where one level set is playable under either ruleset (as is the case with the original
level set). The author can then provide one data file and two configuration files to make both versions
available.
lastlevel = levelnum
This line marks an arbitrary level as being the last level in the set. The game will stop when this level
is completed, instead of proceeding to the next level. (Note that if the data file contains any levels
beyond this one, they will only be reachable via a password.)
fixlynx = y|n
This line is specifically for use with the original level set. It is not generally useful, and is
described here only for completeness. The chips.dat file that MS distributed with their version of
"Chip's Challenge" contained a few minor differences from the original level set as appeared on the Lynx.
A positive value for this entry instructs the program to undo those changes, so that the original Lynx
level set is obtained. (The changes made in the MS version were: an extra level was added; four passwords
were garbled; and four or five levels' maps had minor alterations.)
RESOURCES
Tile World loads various resources at runtime from its resource directory (cf DIRECTORIES). These
resources include the program's font, graphic images, and sound effects. The actual file names are
determined by the contents of a file named rc (short for "resource configuration", not "runtime
commands") in the same directory.
The rc file is a plain text file, and contains lines of the form
resource = filename
where resource is a symbolic resource name, and filename is the name of a file in the resource directory.
The resources can be set differently depending on the ruleset that the program is using. A line in the rc
file of the form
[ ruleset]
indicates that the lines that follow only apply when that ruleset is in effect (where ruleset is either
MS or Lynx). Resources that are defined before any such line apply to both rulesets, and are also used as
fallbacks if a ruleset-specific resource could not be loaded. (The font and the text-color resources also
need to have ruleset-independent values, as these are needed when displaying the initial file list,
before a ruleset has been chosen.)
A line of the form
TileImages = FILENAME
identifies the file that provides the images used to draw the game. These images are stored in a Windows
bitmap. (See the Tile World website for more information about this resource.)
A line of the form
Font = FILENAME
identifies the file that provides the program's font. The font is stored as a Windows bitmap. (See the
Tile World website for more information about this resource.)
A line of the form
UnsolvableList = FILENAME
identifies the filename for the database of unsolvable levels. See DATABASE OF UNSOLVABLE LEVELS below
for more information about this file. Note that this resource must be defined independent of the ruleset,
or else it will be ignored.
Four resources define the colors used in rendering text:
BackgroundColor = RRGGBB
TextColor = RRGGBB
BoldTextColor = RRGGBB
DimTextColor = RRGGBB
The value of RRGGBB is a string of six hexadecimal digits defining the red, green, and blue values of the
color (as with the color specification used in HTML or X Windows, but without the preceding octothorpe).
The remaining resources all define the game's sound effects. The sounds are stored as Microsoft RIFF
files (so-called wave files). Unlike the tile images, each sound effect is defined as a separate file.
The complete list of symbolic resource names is as follows:
Sounds used in both rulesets
* LevelCompleteSound
* ChipDeathSound
* BlockedMoveSound
* PickupToolSound
* ThiefSound
* TeleportSound
* OpenDoorSound
* SocketSound
* SwitchSound
* BombSound
* SplashSound
Sounds used only under the MS ruleset
* TickSound
* ChipDeathByTimeSound
* PickupChipSound
Sounds used only under the Lynx ruleset
* TileEmptiedSound
* WallCreatedSound
* TrapEnteredSound
* BlockMovingSound
* SkatingForwardSound
* SkatingTurnSound
* SlidingSound
* SlideWalkingSound
* IceWalkingSound
* WaterWalkingSound
* FireWalkingSound
(Note that the symbolic names for the shared and MS-only sounds match the names in the entpack.ini file
used by the Microsoft program. This makes it easy for someone with a copy of Microsoft's "Chip's
Challenge" to use the sound effects that were provided with that version of the game.)
DATABASE OF UNSOLVABLE LEVELS
Of the many thousands of user-created levels that are publicly available, there are some that are not
possible to complete. Some of these are intentionally so (e.g. requiring the player to deduce the
password to the next level). The remainder, however, are simply due to poor design, and there is
typically no indication that attempting to solve these levels is fruitless.
To help alleviate this, Tile World comes with a database of levels that have been identified by the
community to be definitely unsolvable. When the player visits a level that appears in this database, a
warning is displayed, and the password to the next level is automatically supplied.
The main database of unsolvable levels is stored in the resource directory. In addition, a player can
keep a separate database in a file of the same name in the directory for solution files. If present, Tile
World will use the information from both of these files.
The offending levels are identified by content as well as by name and number, so that updated versions
will no longer be identified as unsolvable. See the Tile World website for more information about the
format of this file, and to check for updates to the database.
DIRECTORIES
Tile World uses four different directories for storing external files. The following list enumerates the
directories and describes their purpose. The default directories that the program uses can be configured
at compile time. The directories can also be changed at runtime via command-line options and/or
environment variables (see below).
Sets This directory is used to hold the available level sets. The files in this directory are either
data files or configuration files. (default for Linux: /usr/local/share/tworld/sets)
Data This directory is used to hold the data files that are referenced by configuration files. (default
for Linux: /usr/local/share/tworld/data)
Res This directory stores the graphics and sound files used by the program. (default for Linux:
/usr/local/share/tworld/res)
Save This directory is used for saving solution files. (default for Linux: ~/.tworld)
ENVIRONMENT VARIABLES
Two environment variables can be used to override the program's built-in defaults for which directories
to use. They are as follows:
TWORLDDIR
Specifies a top-level directory, in which the program will look for the resource, level set, and
data file directories.
TWORLDSAVEDIR
Specifies a directory for saving solution files.
LICENSE
Tile World is copyright (C) 2001-2015 by Brian Raiter.
This program is free software; you can redistribute it and/or modify it under the terms of the GNU
General Public License as published by the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful, but without any warranty; without even
the implied warranty of merchantability or fitness for a particular purpose. See the GNU General Public
License for more details.
Please send bug reports to breadbox@muppetlabs.com.
HISTORY
"Chip's Challenge" was created by Chuck Sommerville, and was originally written for the Atari Lynx
handheld game console. ("Tile World" was his working title for the game.) "Chip's Challenge" was
published by Epyx (the company who designed the Lynx before selling the rights to Atari) in 1989, and was
among the first set of games made available for the Lynx.
"Chip's Challenge" was subsequently ported to several other platforms: MS-DOS, Microsoft Windows
(16-bit), Amiga, ZX Spectrum, Atari ST, and the Commodore 64. (A NES port was also planned, but never
completed.)
The Windows port was not done by the original team at Epyx. Instead it was done by Microsoft and sold as
part of Windows Entertainment Pack 4 (and later as part of Best of Windows Entertainment Pack). In the
process of recreating the game for the 16-bit Windows platform, Microsoft introduced a surprising number
of changes to the mechanics of the game. Some were clearly intentional, some were done through ignorance
or indifference, and others were simply bugs in the program. The programs in WEP4 came pre-installed on
many PC computers sold during the 1990s, which is part of the reason why this particular version became
the most popular. A small but fanatically loyal community of adherents to the game connected via a MSN
chatroom (and later through the internet). A few members of this community managed to decipher the format
of the MS game's data file, and John K. Elion subsequently created a freeware level editor, called
ChipEdit. As a result there are now hundreds of new level sets, created by fans of the game and all
freely available.
Atari discontinued support for the Lynx in 1994. When Epyx went under, the rights to their games were
purchased by Bridgestone Multimedia. Responding to the success of "Chip's Challenge", Chuck Sommerville
created a sequel, called "Chip's Challenge 2". The sequel included the original game as a proper subset,
and the company held the rights to both games. Bridgestone Multimedia was not interested in publishing
the game, however, and so made no effort to release it.
Microsoft no longer sells any of the Entertainment Packs, so the older Windows version of "Chip's
Challenge" is no longer (legally) available to newcomers except by finding used copies for sale.
In 2001, the author began writing "Tile World" with the intention of recreating a version of the MS game
for the Linux platform. At the encouragement of Chuck Sommerville, this project was expanded to include
the goals of recreating the original Lynx game as well, and also making the program work under MS Windows
in addition to Linux. Version 1.0 was released in 2002. Version 1.3 was released in 2006.
In 2015 Chuck Sommerville finally managed to strike a deal with Bridgestone Multimedia and get Chips
Challenge 2 published on Steam. Since this release also includes the original levels, with the name
officially being "Chip's Challenge 1", there is now yet another variation of the original ruleset.
APPENDIX: NOTES ON NOMENCLATURE
"Chip's Challenge" has seen several incarnations. Each had its own graphical rendering, and thus many of
the objects in the game are known by more than one name. For example, the four types of boots in the MS
version of the game were known as fire boots, flippers (for water), skates (for ice), and suction boots
(for force floors). In the original Lynx version, however, they were not even boots -- the four tools
were fire shields, water shields, cleats, and magnets, respectively. With the CC2 release, the objects
have returned to being boots, but the suction boots are now called magno boots.
Several of the creatures have seen a variety of names. The list of creatures given in OVERVIEW OF THE
GAME corresponds to the MS version of the game. In the original Lynx version, the paramecia were
centipedes instead. In still other versions of the game, gliders were referred to as ghosts or sharks,
fireballs were flames, and teeth were called frogs. (You will also occasionally see bugs referred to as
bees, and walkers referred to as dumbbells.)
Finally, the thief tile was called a spy in the MS version.
None of this information is needed in order to play the game, but it helps to explain the titles of some
of the user-created levels.