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

NAME

       sgt-bridges - Bridge-placing puzzle

SYNOPSIS

       sgt-bridges  [--generate n] [--print wxh [--with-solutions] [--scale n] [--colour]] [game-
       parameters|game-ID|random-seed]

       sgt-bridges --version

DESCRIPTION

       You have a set of islands distributed across the playing  area.  Each  island  contains  a
       number. Your aim is to connect the islands together with bridges, in such a way that:

       ·      Bridges run horizontally or vertically.

       ·      The  number  of bridges terminating at any island is equal to the number written in
              that island.

       ·      Two bridges may run in parallel between the same two islands, but no more than  two
              may do so.

       ·      No bridge crosses another bridge.

       ·      All the islands are connected together.

       There  are some configurable alternative modes, which involve changing the parallel-bridge
       limit to something other than  2,  and  introducing  the  additional  constraint  that  no
       sequence  of  bridges  may  form a loop from one island back to the same island. The rules
       stated above are the default ones.

       Credit for this puzzle goes to Nikoli (http://www.nikoli.co.jp/puzzles/14/index-e.htm).

       Bridges was contributed to this collection by James Harvey.

Bridges controls

       To place a bridge between two islands, click the mouse down on  one  island  and  drag  it
       towards  the other. You do not need to drag all the way to the other island; you only need
       to move the mouse far enough for the intended bridge direction to be unambiguous. (So  you
       can  keep the mouse near the starting island and conveniently throw bridges out from it in
       many directions.)

       Doing this again when a bridge is already present will add  another  parallel  bridge.  If
       there are already as many bridges between the two islands as permitted by the current game
       rules (i.e. two by default), the same dragging action will remove all of them.

       If you want to remind yourself that two islands definitely do not have  a  bridge  between
       them, you can right-drag between them in the same way to draw a ‘non-bridge’ marker.

       If  you  think  you have finished with an island (i.e. you have placed all its bridges and
       are confident that they are in the right places), you can mark the island as  finished  by
       left-clicking  on  it. This will highlight it and all the bridges connected to it, and you
       will be prevented from accidentally modifying  any  of  those  bridges  in  future.  Left-
       clicking  again  on a highlighted island will unmark it and restore your ability to modify
       it.

       You can also use the cursor keys to move around the grid:  if  possible  the  cursor  will
       always  move  orthogonally,  otherwise  it  will  move  towards  the nearest island to the
       indicated direction. Pressing the return key followed by a cursor key will lay a bridge in
       that  direction (if available); pressing the space bar followed by a cursor key will lay a
       ‘non-bridge’ marker.

       You can mark an island as finished by pressing the return key twice.

       Violations of the puzzle rules will be marked in red:

       ·      An island with too many bridges will be highlighted in red.

       ·      An island with too few bridges will be highlighted in red if it  is  definitely  an
              error (as opposed to merely not being finished yet): if adding enough bridges would
              involve having to cross another bridge or remove a non-bridge  marker,  or  if  the
              island has been highlighted as complete.

       ·      A  group  of islands and bridges may be highlighted in red if it is a closed subset
              of the puzzle with no way to connect it to the rest of the islands. For example, if
              you  directly  connect  two 1s together with a bridge and they are not the only two
              islands on the grid, they will light up red to indicate that such a group cannot be
              contained in any valid solution.

       ·      If  you have selected the (non-default) option to disallow loops in the solution, a
              group of bridges which forms a loop will be highlighted.

       (All the actions described below are also available.)

Bridges parameters

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

       Width, Height
              Size of grid in squares.

       Difficulty
              Difficulty level of puzzle.

       Allow loops
              This is set by default. If cleared, puzzles will be generated in such  a  way  that
              they  are  always soluble without creating a loop, and solutions which do involve a
              loop will be disallowed.

       Max. bridges per direction
              Maximum number of bridges in any particular direction. The default is  2,  but  you
              can change it to 1, 3 or 4. In general, fewer is easier.

       %age of island squares
              Gives a rough percentage of islands the generator will try and lay before finishing
              the puzzle. Certain layouts will not manage to lay enough islands; this is an upper
              bound.

       Expansion factor (%age)
              The  grid  generator  works  by  picking  an existing island at random (after first
              creating an initial island somewhere). It then decides on a direction (at  random),
              and  then  works  out  how far it could extend before creating another island. This
              parameter determines how likely it is to extend as  far  as  it  can,  rather  than
              choosing somewhere closer.

              High expansion factors usually mean easier puzzles with fewer possible islands; low
              expansion factors can create lots of tightly-packed islands.

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
              programs.

       ·      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:

       --game

       --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.

       --version
              Prints version information about the game, and then quits.

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

       --with-solutions
              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.

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

SEE ALSO

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