Provided by: tworld_1.3.0-6_amd64 bug


       tworld - Tile World


       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.


       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 chip, 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
       * 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
       * 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.


       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.


       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.


       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.)

              increases the volume level.

       At the start of a  level,  before  game  play  begins,  the  following  key  commands  are

       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

       Tab    plays back the best solution for that level.

              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.

              same as Shift-Tab.

       O      toggles between even-step and odd-step offset.

              (Lynx-mode only) increments the stepping offset by one.

       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.

              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

       ?      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.)


       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.


       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).


       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     Double the size of the audio buffer. This option can be repeated,  so  for  example
              -aaa would increase the audio buffer size eightfold.

       -b     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 DIR Read level data files from DIR instead of the default directory.

       -d     Display the default directories used by the program on standard output, and exit.

       -F     Run in full-screen mode.

       -H     Upon exit, display a histogram of idle time on standard  output.  (This  option  is
              used for evaluating optimization efforts.)

       -h     Display a summary of the command-line syntax on standard output and exit.

       -L DIR Look for level sets in DIR instead of the default directory.

       -l     Write a list of available level sets to standard output and exit.

       -n N   Set  the  initial  volume level to N, 0 being silence and 10 being full volume. The
              default level is 10.

       -P     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     Turn off all password-checking. This option allows the normal sequence of levels to
              be bypassed.

       -q     Run  quietly.  All  sounds,  including  the  ringing  of  the  terminal  bell,  are

       -r     Run in read-only mode. This guarantees that no changes will be made to the solution

       -R DIR Read resource data from DIR instead of the default directory.

       -S DIR Read and write solution files under DIR instead of the default directory.

       -s     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     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  -b,  the  solutions  are
              verified beforehand, and invalid solutions are indicated.

       -V     Display the program's version and license information on standard output and exit.

       -v     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 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.

       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

       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.)


       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

       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.)


       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


       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:

       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)


       Two environment variables can be used to override  the  program's  built-in  defaults  for
       which directories to use. They are as follows:

              Specifies  a  top-level directory, in which the program will look for the resource,
              level set, and data file directories.

              Specifies a directory for saving solution files.


       Tile World is copyright (C) 2001-2006 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


       "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

       "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 different from most (perhaps all?) of the others in that it  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 dozens 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 ("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, who has now become Alpha Omega Publications, unfortunately did not
       see fit to actually release "Chip's Challenge 2", and by now it is highly unlikely that it
       ever will be released. Since Chuck Sommerville no longer has rights to  either  game,  and
       Microsoft  no  longer  sells  either  of  the  Entertainment  Packs,  the original "Chip's
       Challenge" is no longer available  except  by  purchasing  a  used  copy  of  one  of  the
       aforementioned Entertainment Packs (or by downloading an illegal copy).

       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.


       "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.

       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.