In my article series about programming for the text console using the ncurseslibrary, I showed you how to draw text on the screen and use basic textattributes. My examples of Sierpinski's Triangle (see "GettingStarted with ncurses") and a simple Questadventure game (see "Creatingan Adventure Game in the Terminal with ncurses") used the entire screen at once.
Install Ncurses Windows 7
You may associate "windows" with a graphical environment, but that isnot the case here. In ncurses, "windows" are a means to divide thescreen into logical areas. Once you define a window, you don't need totrack its location on the screen; you just draw to your window using a set ofncurses functions.
Without the windows functions, you'd have to keep track of the row andcolumn for each piece and draw them separately. Since the board is arrangedin a backward "S" pattern, you'll always need to do weird mathto position the row and column correctly every time you update each square onthe board. But with the windows functions, ncurses lets you define the squaresonce, including their position, and later refer to those windows by a logicalidentifier.
The newwin() function returns a pointer of typeWINDOW* that you can store inan array for later reference. To create a Senet board, you can use a globalarray BOARD[30], and write a function to define the 30 squares of theSenet board using windows:
Text windows in ncurses don't create a "frame" to show the windowon the screen. If you want to draw a frame, you can do so using one of twofunctions. Here, after defining the windows, the function then calls thencurses function box() to draw the square on the screen.Normally, the box()function takes arguments for the characters to use for the vertical andhorizontal borders; if you pass zero as either or both arguments, ncursesuses a default line-drawing character.
The draw_square() function shows two ways to draw a frame on a text window. Icovered the box() function earlier. The other method is with thewborder()function, which takes separate arguments for the left, right, top and bottomedges of the window, and the upper-left, upper-right, lower-left andlower-right corners. As with box(), if you pass zero as any or all of thearguments, ncurses will use a default line-drawing character.
Because this uses the windows functions, the draw_square() functiondoesn't need to know the location of each square. That's all trackedby ncurses as an attribute of the 30 windows that make up the 30squares on the board. Once the program defines the windows, including theirposition, drawing to each square is a simple call to an associated"w" function, referencing the window to draw to.
Now that you've seen how to use windows to create 30 independentdrawing areas, let's walk through a simple program to draw a Senet boardand allow the user to navigate through the squares using the plus and minuskeys. At a high level, the program follows these steps:
This is just the bare bones of a Senet game. All it does is generate a gameboard and allow the user to navigate through all of the squares. To keepthis focused on the windows functions in ncurses, I've left out all thegameplay and rules.
This program is a simple example of how to use nurses windows functions todefine separate areas on the screen. The sample program is a game, but youcan use this as a starting point for your own programs. Any program thatrequires updating multiple areas of the screen can use the windows functions.
The ncurses library provides a rich set of functions to update and access thescreen in text mode. While graphical user interfaces are very cool, not everyprogram needs to run with a point-and-click interface. If your program runsin plain-text terminals, consider using ncurses to manipulate the terminalscreen.
ACS_Character is a special character used when dealing with line graphics. These are automatically determined at runtime by ncurses and thus cannot be defined as constants. Instead, they are accessible statically via the Window class after at least one window has been created (so that ncurses has initialized this special character set). See the Additional notes at the bottom for a list of the available characters.
cleanup() - (void) - Restores the terminal after using ncurses. This function is automatically called when the last window is closed and thus should never be used except when handling unexpected exceptions (i.e. in node.js's uncaughtException event) so that you can safely restore the terminal back to normal.
idlok(useInsDelLine) - Result - If useInsDelTerm is true, ncurses considers using the hardware insert/delete line feature of the terminal (if available). Otherwise if useInsDelTerm is false, hardware line insertion and deletion is disabled. This option should be enabled only if the application needs insert/delete line, for example, for a screen editor. It is disabled by default because insert/delete line tends to be visually annoying when used in applications where it isn't really needed. If insert/delete line cannot be used, ncurses redraws the changed portions of all lines.
idcok(useInsDelChar) - Result - If useInsDelChar is true, ncurses considers using the hardware insert/delete character feature of the terminal (if available). Otherwise if useInsDelChar is false, ncurses no longer considers using the hardware insert/delete character feature of the terminal. Use of character insert/delete is enabled by default.
leaveok(moveCursor) - Result - Normally, the hardware cursor is left at the location of the window cursor being refreshed. If moveCursor is true, ncurses will allow the cursor to be left wherever an update happens to leave it. It is useful for applications where the cursor is not used, since it reduces the need for cursor motions. If possible, the cursor is made invisible when this function is called.
syncdown() - Result - Touches each location in the window that has been touched in any of its ancestor windows. This function is called by refresh(), so it should almost never be necessary to call it manually.
box([vertChar=0[, horizChar=0]]) - Result - Draws a box around the window using the optional vertical and horizontal characters. If a zero is given for any of the arguments, ncurses will use the POSIX default characters instead (See Additional notes).
border([leftChar=0[, rightChar=0[, topChar=0[, bottomChar=0[, topLeftChar=0[, topRightChar=0[, bottomLeftChar=0[, bottomRightChar=0]]]]]]]]) - Result - Draws a border around the window using the optionally specified left, right, top, bottom, top left, top right, bottom left, bottom right characters. If any of the characters are zero, ncurses will use the POSIX default characters instead (See Additional notes).
hline(length[, lineChar=0]) - Result - Draws a horizontal line on the current row with the given length. lineChar specifies the character to be used when drawing the line. If lineChar is zero, ncurses will use the POSIX default characters instead (See Additional notes).
vline(length[, lineChar=0]) - Result - Draws a vertical line on the current column with the given length. lineChar specifies the character to be used when drawing the line. If lineChar is zero, ncurses will use the POSIX default characters instead (See Additional notes).
A resize operation in X sends SIGWINCH to the running application. The ncurses library does not catch this signal, because it cannot in general know how you want the screen re-painted. You will have to write the SIGWINCH handler yourself.
Note that this script will ask for root access using sudo in orderto use your platform's package manager to install dependencies and toinstall to /usr/local/bin. If you prefer more control, follow themanual installation instructions for your platform below.
You may see a "Windows Defender SmartScreen prevented an unrecognized app fromstarting" warning when you try to run the installer. If so, click onMore info, and then click on the Run anyway button that appears.
There is also a Ubuntupackagefor Ubuntu 16.10 and up, but the distribution's Stack version lags behind, so werecommend running stack upgrade --binary-only after installing it. For older stackversions which do not support --binary-only, just stack upgrade may work too. Theversion in Ubuntu 16.04 is too old to upgrade successfully, and so in that casestack should be installed from a releasetarball.
There is also a Debianpackagefor Stretch and up, but the distribution's Stack version lags behind, so runningstack upgrade --binary-only is recommended after installing it. For older stackversions which do not support --binary-only, just stack upgrade may work too.
There is also anunofficialFedora Copr repo whichcan be enabled with: sudo dnf copr enable petersen/stack2. Note that this Stackversion may lag behind, so we recommend running stack upgrade after installingit.
In order to use stack setup with older versions of GHC or on a 32-bit system,you may need thencurses5-compat-libsAUR package installed. If this package is not installed, Stack may not be ableto install older (
You can install stack by copying it anywhere on your PATH environment variable. A good place to install is the same directory where stack itself will install executables. On Windows, that directory is %APPDATA%\local\bin, e.g. c:\Users\Michael\AppData\Roaming\local\bin. For other systems, it's $HOME/.local/bin.
As of 2020-02-24, the download link has limited connectivity from within mainland China. If this is the case, please proceed by manually downloading (ideally via a VPN) and installing stack per the instructions found on this page pertinent to your OS.
After install, your /.stack/config.yaml will need to be configured before stack can download large files consistently from within China (without reliance on a VPN). Please add the following to the bottom of the /.stack/config.yaml file (for Windows: use the %STACK_ROOT%\config.yaml): 2ff7e9595c
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