Provided by: sgt-puzzles_20140928.r10274-1_amd64 bug


       sgt-blackbox - Ball-finding puzzle


       sgt-blackbox [--generate n] [--print wxh [--with-solutions] [--scale n] [--colour]] [game-

       sgt-blackbox --version


       A number of balls are hidden in a rectangular arena. You have to deduce the  positions  of
       the  balls  by  firing lasers positioned at the edges of the arena and observing how their
       beams are deflected.

       Beams will travel straight from their origin until they hit the opposite side of the arena
       (at which point they emerge), unless affected by balls in one of the following ways:

       ·      A beam that hits a ball head-on is absorbed and will never re-emerge. This includes
              beams that meet a ball on the first rank of the arena.

       ·      A beam with a ball to its front-left square gets deflected 90 degrees to the right.

       ·      A beam with a ball to its front-right square gets similarly deflected to the left.

       ·      A  beam  that  would  re-emerge  from  its  entry  location  is  considered  to  be

       ·      A  beam which would get deflected before entering the arena by a ball to the front-
              left or front-right of its entry point is also considered to be ‘reflected’.

       Beams that are reflected appear as a ‘R’; beams that hit  balls  head-on  appear  as  ‘H’.
       Otherwise,  a  number  appears at the firing point and the location where the beam emerges
       (this number is unique to that shot).

       You can place guesses as to the location of  the  balls,  based  on  the  entry  and  exit
       patterns  of the beams; once you have placed enough balls a button appears enabling you to
       have your guesses checked.

       Here is a diagram showing how  the  positions  of  balls  can  create  each  of  the  beam
       behaviours shown above:


       As  shown,  it  is  possible for a beam to receive multiple reflections before re-emerging
       (see turn 3). Similarly, a  beam  may  be  reflected  (possibly  more  than  once)  before
       receiving a hit (the ‘H’ on the left side of the example).

       Note  that any layout with more than 4 balls may have a non-unique solution. The following
       diagram illustrates this; if you know the board contains 5  balls,  it  is  impossible  to
       determine where the fifth ball is (possible positions marked with an x):


       For  this  reason,  when  you  have  your  guesses  checked, the game will check that your
       solution produces the same results as the computer's, rather than that  your  solution  is
       identical  to the computer's. So in the above example, you could put the fifth ball at any
       of the locations marked with an x, and you would still win.

       Black Box was contributed to this collection by James Harvey.

Black Box controls

       To fire a laser beam, left-click in a square around the edge of  the  arena.  The  results
       will be displayed immediately. Clicking or holding the left button on one of these squares
       will highlight the current go (or a previous go) to confirm the exit point for that laser,
       if applicable.

       To  guess  the  location  of  a  ball, left-click within the arena and a black circle will
       appear marking the guess; click again to remove the guessed ball.

       Locations in the arena may be locked against modification by  right-clicking;  whole  rows
       and columns may be similarly locked by right-clicking in the laser square above/below that
       column, or to the left/right of that row.

       The cursor keys may also be used to move around the grid. Pressing the Enter key will fire
       a  laser  or  add  a new ball-location guess, and pressing Space will lock a cell, row, or

       When an appropriate number of balls have been guessed, a button will appear  at  the  top-
       left corner of the grid; clicking that (with mouse or cursor) will check your guesses.

       If  you  click the ‘check’ button and your guesses are not correct, the game will show you
       the minimum information necessary to demonstrate this to you, so you  can  try  again.  If
       your  ball  positions  are  not consistent with the beam paths you already know about, one
       beam path will be circled to indicate that it proves you wrong. If  your  positions  match
       all  the  existing  beam  paths  but  are  still wrong, one new beam path will be revealed
       (written in red) which is not consistent with your current guesses.

       If you decide to give up completely, you can  select  Solve  to  reveal  the  actual  ball
       positions.  At  this  point,  correctly-placed  balls  will  be  displayed as filled black
       circles, incorrectly-placed balls as filled black circles with red  crosses,  and  missing
       balls  as  filled  red  circles. In addition, a red circle marks any laser you had already
       fired which is not consistent with your ball layout (just as when you  press  the  ‘check’
       button),  and  red  text marks any laser you could have fired in order to distinguish your
       ball layout from the correct one.

       (All the actions described below are also available.)

Black Box parameters

       These parameters are available from the ‘Custom...’ option on the ‘Type’ menu.

       Width, Height
              Size of grid in squares. There are 2 × Width × Height lasers per grid, two per  row
              and two per column.

       No. of balls
              Number  of  balls  to  place  in  the grid. This can be a single number, or a range
              (separated with a hyphen, like ‘2-6’), and determines the number of balls to  place
              on the grid. The ‘reveal’ button is only enabled if you have guessed an appropriate
              number of balls; a guess using a different number to the original solution is still
              acceptable, if all the beam inputs and outputs match.

Common actions

       These  actions  are  all  available  from  the  ‘Game’ menu and via keyboard shortcuts, in
       addition to any game-specific actions.

       (On Mac OS X, to conform with local user interface standards, these actions  are  situated
       on the ‘File’ and ‘Edit’ menus instead.)

       New game (‘N’, Ctrl+‘N’)
              Starts a new game, with a random initial state.

       Restart game
              Resets the current game to its initial state. (This can be undone.)

       Load   Loads a saved game from a file on disk.

       Save   Saves the current state of your game to a file on disk.

              The  Load  and  Save operations preserve your entire game history (so you can save,
              reload, and still Undo and Redo things you had done before saving).

       Print  Where supported (currently only on Windows), brings up a  dialog  allowing  you  to
              print   an  arbitrary  number  of  puzzles  randomly  generated  from  the  current
              parameters, optionally including the current puzzle. (Only for puzzles  which  make
              sense  to  print,  of  course  –  it's  hard  to  think  of  a  sensible  printable
              representation of Fifteen!)

       Undo (‘U’, Ctrl+‘Z’, Ctrl+‘_’)
              Undoes a single move. (You can undo moves back to the start of the session.)

       Redo (‘R’, Ctrl+‘R’)
              Redoes a previously undone move.

       Copy   Copies the current state of your game to the clipboard in text format, so that  you
              can  paste  it  into  (say)  an  e-mail  client  or  a  web message board if you're
              discussing the game with someone else. (Not all games support this feature.)

       Solve  Transforms the puzzle instantly into its solved state. For some games  (Cube)  this
              feature is not supported at all because it is of no particular use. For other games
              (such as Pattern), the solved state can be used to give  you  information,  if  you
              can't  see  how  a  solution  can exist at all or you want to know where you made a
              mistake. For still other games (such as  Sixteen),  automatic  solution  tells  you
              nothing  about  how to get to the solution, but it does provide a useful way to get
              there quickly so that you can experiment with set-piece moves and transformations.

              Some games (such as Solo) are capable of solving a game ID you have typed  in  from
              elsewhere.  Other  games  (such  as  Rectangles) cannot solve a game ID they didn't
              invent themself, but when they did invent the game ID they know what  the  solution
              is  already. Still other games (Pattern) can solve some external game IDs, but only
              if they aren't too difficult.

              The ‘Solve’ command adds the solved state to the end of  the  undo  chain  for  the
              puzzle.  In other words, if you want to go back to solving it yourself after seeing
              the answer, you can just press Undo.

       Quit (‘Q’, Ctrl+‘Q’)
              Closes the application entirely.

Specifying games with the game ID

       There are two ways to save a game specification out of a puzzle and recreate it later,  or
       recreate it in somebody else's copy of the same puzzle.

       The  ‘Specific’ and ‘Random Seed’ options from the ‘Game’ menu (or the ‘File’ menu, on Mac
       OS X) each show a piece of text (a ‘game ID’) which is sufficient to reconstruct precisely
       the same game at a later date.

       You  can  enter  either  of  these  pieces  of  text  back  into the program (via the same
       ‘Specific’ or ‘Random Seed’ menu options) at a later point, and it will recreate the  same
       game.  You  can  also  use either one as a command line argument (on Windows or Unix); see
       below for more detail.

       The difference between the  two  forms  is  that  a  descriptive  game  ID  is  a  literal
       description  of  the  initial  state of the game, whereas a random seed is just a piece of
       arbitrary text which was provided as input to the random number generator used  to  create
       the puzzle. This means that:

       ·      Descriptive game IDs tend to be longer in many puzzles (although some, such as Cube
              (sgt-cube(6)), only need very short descriptions). So a  random  seed  is  often  a
              quicker  way  to  note  down  the puzzle you're currently playing, or to tell it to
              somebody else so they can play the same one as you.

       ·      Any text at all is a valid  random  seed.  The  automatically  generated  ones  are
              fifteen-digit  numbers,  but anything will do; you can type in your full name, or a
              word you just made up, and a valid puzzle will be generated from it. This  provides
              a  way  for  two or more people to race to complete the same puzzle: you think of a
              random seed, then everybody types it in  at  the  same  time,  and  nobody  has  an
              advantage due to having seen the generated puzzle before anybody else.

       ·      It  is often possible to convert puzzles from other sources (such as ‘nonograms’ or
              ‘sudoku’ from newspapers) into descriptive game IDs suitable  for  use  with  these

       ·      Random  seeds  are not guaranteed to produce the same result if you use them with a
              different version of the puzzle program. This is because the  generation  algorithm
              might  have  been  improved  or  modified  in  later versions of the code, and will
              therefore produce a different  result  when  given  the  same  sequence  of  random
              numbers.  Use  a descriptive game ID if you aren't sure that it will be used on the
              same version of the program as yours.

              (Use the ‘About’ menu option to  find  out  the  version  number  of  the  program.
              Programs  with  the same version number running on different platforms should still
              be random-seed compatible.)

       A descriptive game ID starts with a piece of text which  encodes  the  parameters  of  the
       current game (such as grid size). Then there is a colon, and after that is the description
       of the game's initial state. A random seed starts with a similar string of parameters, but
       then it contains a hash sign followed by arbitrary data.

       If  you  enter  a descriptive game ID, the program will not be able to show you the random
       seed which generated it, since it wasn't generated from a random  seed.  If  you  enter  a
       random seed, however, the program will be able to show you the descriptive game ID derived
       from that random seed.

       Note that the game parameter strings are not always identical between the two  forms.  For
       some  games,  there  will  be  parameter  data  provided with the random seed which is not
       included in the descriptive game ID. This is because that parameter  information  is  only
       relevant  when  generating puzzle grids, and is not important when playing them. Thus, for
       example, the difficulty level in Solo (sgt-solo(6)) is not mentioned  in  the  descriptive
       game ID.

       These  additional  parameters  are  also not set permanently if you type in a game ID. For
       example, suppose you have Solo set to ‘Advanced’ difficulty level, and then a friend wants
       your  help  with  a  ‘Trivial’  puzzle;  so  the friend reads out a random seed specifying
       ‘Trivial’ difficulty, and you type it in. The program will generate you the same ‘Trivial’
       grid  which  your  friend  was having trouble with, but once you have finished playing it,
       when you ask for a new game it will automatically go back  to  the  ‘Advanced’  difficulty
       which it was previously set on.

The ‘Type’ menu

       The  ‘Type’ menu, if present, may contain a list of preset game settings. Selecting one of
       these will start a new random game with the parameters specified.

       The ‘Type’ menu may also contain a ‘Custom’ option which  allows  you  to  fine-tune  game
       parameters.  The  parameters  available are specific to each game and are described in the
       following sections.

Specifying game parameters on the command line

       (This section does not apply to the Mac OS X version.)

       The games in this collection deliberately do not ever save information on to the  computer
       they  run  on: they have no high score tables and no saved preferences. (This is because I
       expect at least some people  to  play  them  at  work,  and  those  people  will  probably
       appreciate leaving as little evidence as possible!)

       However,  if  you do want to arrange for one of these games to default to a particular set
       of parameters, you can specify them on the command line.

       The easiest way to do this is to set up the parameters you want using the ‘Type’ menu (see
       above),  and  then to select ‘Random Seed’ from the ‘Game’ or ‘File’ menu (see above). The
       text in the ‘Game ID’ box will be composed of two parts, separated by a hash. The first of
       these parts represents the game parameters (the size of the playing area, for example, and
       anything else you set using the ‘Type’ menu).

       If you run the game with just that parameter text on the command line, it  will  start  up
       with the settings you specified.

       For  example: if you run Cube (see sgt-cube(6)), select ‘Octahedron’ from the ‘Type’ menu,
       and  then  go  to  the  game  ID  selection,  you  will  see  a   string   of   the   form
       ‘o2x2#338686542711620’.  Take  only the part before the hash (‘o2x2’), and start Cube with
       that text on the command line: ‘sgt-cube o2x2’.

       If you copy the entire game ID on to the command line, the  game  will  start  up  in  the
       specific  game  that  was described. This is occasionally a more convenient way to start a
       particular game ID than by pasting it into the game ID selection box.

       (You could also retrieve the encoded game parameters  using  the  ‘Specific’  menu  option
       instead of ‘Random Seed’, but if you do then some options, such as the difficulty level in
       Solo, will be missing. See above for more details on this.)

Unix command-line options

       (This section only applies to the Unix port.)

       In addition to being able to specify game parameters on  the  command  line  (see  above),
       there are various other options:


       --load These  options  respectively determine whether the command-line argument is treated
              as specifying game parameters or a save file to load. Only one should be specified.
              If  neither  of  these options is specified, a guess is made based on the format of
              the argument.

       --generate n
              If this option is specified, instead of a  puzzle  being  displayed,  a  number  of
              descriptive  game  IDs  will  be  invented  and printed on standard output. This is
              useful for gaining access to the game  generation  algorithms  without  necessarily
              using the frontend.

              If game parameters are specified on the command-line, they will be used to generate
              the game IDs; otherwise a default set of parameters will be used.

              The most common use of this option is in conjunction with --print,  in  which  case
              its behaviour is slightly different; see below.

       --print wxh
              If  this  option  is  specified,  instead  of  a  puzzle being displayed, a printed
              representation of one or more unsolved puzzles  is  sent  to  standard  output,  in
              PostScript format.

              On  each  page  of  puzzles,  there  will be w across and h down. If there are more
              puzzles than w×h, more than one page will be printed.

              If --generate has also been specified, the  invented  game  IDs  will  be  used  to
              generate  the printed output. Otherwise, a list of game IDs is expected on standard
              input (which can be descriptive or random seeds; see above),  in  the  same  format
              produced by --generate.

              For example:

              sgt-net --generate 12 --print 2x3 7x7w | lpr

              will  generate  two  pages  of  printed  Net puzzles (each of which will have a 7×7
              wrapping grid), and pipe the output to the lpr command, which on many systems  will
              send them to an actual printer.

              There are various other options which affect printing; see below.

       --save file-prefix [ --save-suffix file-suffix ]
              If  this option is specified, instead of a puzzle being displayed, saved-game files
              for one or more unsolved puzzles are written to files constructed from the supplied
              prefix and/or suffix.

              If  --generate  has  also  been  specified,  the  invented game IDs will be used to
              generate the printed output. Otherwise, a list of game IDs is expected on  standard
              input  (which  can  be  descriptive or random seeds; see above), in the same format
              produced by --generate.

              For example:

              sgt-net --generate 12 --save game --save-suffix .sav

              will generate twelve Net saved-game files with the names game0.sav to game11.sav.

              Prints version information about the game, and then quits.

       The following options are only meaningful if --print is also specified:

              The set of pages filled with unsolved puzzles will be followed by the solutions  to
              those puzzles.

       --scale n
              Adjusts  how  big  each puzzle is when printed. Larger numbers make puzzles bigger;
              the default is 1.0.

              Puzzles will be printed in colour, rather than in black and white (if supported  by
              the puzzle).


       Full documentation in /usr/share/doc/sgt-puzzles/puzzles.txt.gz.