gbSudoku is a version of Sudoku, usually described as a number-placement puzzle. The objective is to fill a 9x9 grids with only the digits 1-9, in such a way that no row, column, or "box" (more on that later) has the same number twice. A number of the grids are pre-filled with characters (sometimes called "seed" characters) and it is the player's task to fill in all remaining grids consistent with the rules of placement.
Sudoku games are available online and are carried by a number of magazines and newspapers. By carefully constructing the puzzle, varying levels of difficulty are possible.
gbSudoku can generate Sudoku puzzles and provides a variety of features to make it easy for the user to play the game.
gbSudoku uses a single main window, consisting of two toolbars and a client area where the
game is played.
gbSudoku provides a complete selection of features for playing the game:
- Generate new games
- Enter numbers by keyboard or mouse
- Drag mouse in a cell to select a number to enter
- Highlight location of invalid user inputs
- Reset (remove all user-entered numbers)
- Clear (remove all numbers, allowing user to create their own game)
- Reveal (solve the puzzle for the selected cell)
- Undo/Redo moves
- Numbers available for play in cells may be displayed (suggestion)
- Compact Toolbar mode
- Resize game to 1:1 aspect ratio on demand
- Print/Copy game
- Game may be adjusted to any size
- Game can be stored between sessions
- User-defined colors for cells, numbers and selection marker
- Popup information dialog (cell data)
- Online Help (this page)
Future versions will provide saving/restoring multiple games, selecting level of
difficult, and adding skins to the game GUI. Undo and highlighting of rows/columns/boxes for which a number entry is invalid is also on the list of future enhancements.
When first started, gbSudoku generates a new game. To play the game, select a cell and then select a number (from the toolbar keyboard or by dragging the mouse in a selected cell) to insert into the cell. If the number is a valid entry, it is displayed in the cell. If the number is invalid, the game beeps and makes no changes to the game screen. Game alerts and messages are optional.
Only numbers 1-9 may be displayed in a cell. Press the space button on the toolbar or the number zero from the keyboard to remove the number from the currently selected cell.
When all cells are filled, a sound effect (or voice congratulations) will be played.
If gbSudoku is closed, the current game is save and restored when the gbSudoku is next opened.
The user can navigate to a new cell by clicking on the cell or by pressing the up/down/left/right toolbar buttons.
The Suggest toolbar button toggles the display, in each cell, of all numbers which may be entered into that cell.
The gbSudoku interface includes the following 2 toolbars.
Main Toolbar (Top)
Creates a new Sudoku game
Removes all user-entered numbers from the game
Removes all numbers from the game. Used to create a custom game.
Display the solution number for the selected cell
Undo the most recent user input. The Undo stack does not track a RESET or CLEAR command, nor
does it track actions on individual Note numbers.
Display the next action in the Undo stack
Prints the game screen to a printer of the user's choice. Portrait or landscape is supported.
Copy image of game to clipboard
Removes Notes and Suggestions from cells
Displays Notes in cells
Display Suggestions in cells
Adjusts the height of the game so that it has a 1:1 aspect ratio
When pressed, the Settings button toggles display of information in the dialog caption.
Also, the Settings dropdown menu provides the following menu options:
Enables speech features (declaring bad numbers or game victory)
Asks user to confirm starting a new game or when a reset/clear is requested
Prevent display of highlighted rows/columns/boxes in response to invalid user
number inputs. Also prevents Reveal from eliminating conflicting numbers in
the same row/column/box as the revealed cell.
Automatically saves the current game when gbSudoku is closed, and restores it
when gbSudoku is restarted
Temporarily highlights the row/column/box in which the user attempts to put an invalid number
Toggles between portrait and landscape printer orientation
Show Caption Information
Puts selected cell and elapsed game time in the gbSudoku caption
Allow Drag Number Entry
Allows user to enter a number into a cell by dragging the mouse within the
Removes items from the toolbar which may also be accessed from the toolbar
or the game context menu
Prints the current game to a user-selected printer
Copies an image of the game to the clipboard
Create a temporary file of information about all cells and opens that file in Notepad
Opens a color selection dialog for 1 of 6 different game object colors
Opens the online Help page (this page). The Help dropdown menu provides the
following menu options:
Opens a dialog that provides a summary of Help information
Checks the server for a new version of the gbSudoku EXE
Number/Navigation Toolbar (Bottom)
The bottom toolbar provides number entry and cell navigation features.
When pressed, the blank button removes the number from the selected cell. A space will do the
same thing. Numbers on the keypad or across the keyboard may be used.
Pressing the numbers 1-9 will place the number in the selected cell, unless the number is an invalid entry.
The left/right/down/up arrows keys are used to move to a new cell and select that cell. A mouse click may also be used to select a new cell.
In compact toolbar mode, gbSudoku removes several toolbar buttons (the commands are also in
the Settings dropdown menu or in the game context menu) to allow the user to create a smaller
From the top toolbar, the Empty/Notes/Suggest/Print/Copy buttons are removed.
From the bottom toolbar, the Up/Down/Left/Right arrow buttons are removed.
The following context menu is available by right-mouse clicking over the game area.
The context menu has the following menu options
Same as the toolbar buttons of the same name
- Clear Number (Selected Cell)
Removes the number from the selected cell
- Clear Notes (Selected Cell)
Removes user note highlighting from the selected cell
- Clear Notes (All Cells)
Removes user note highlighting from the all cells
- Toggle Note 1 Status ... Toggle Note 9 Status
Reverse the status of the selected Note number
- Enter the Number 1 ... Enter the Number 9
Enters the selected number in the currently selected cell
The following key combinations are available to the user to access gbSudoku features:
Also, the keyboard and keypad numbers zero through nine act the same as the corresponding number button on the bottom toolbar.
- Ctrl-A - Sets 1:1 aspect ratio
- Ctrl-C - Copies game image to clipboard
- Ctrl-E - Reveals the puzzle solution for the selected cell
- Ctrl-I - Settings Information Dialog
- Ctrl-P - Prints game to user-selected printer
- Ctrl-R - Reset the game (remove all user-entered numbers)
- Ctrl-S - Allow Speech
- Ctrl-U - Undo
Miscellaneous information is provided in this section.
gbSudoku application settings are saved in an INI file, kept in the same folder as the gbSudoku application.
Comments and suggestions are welcome!