vty-5.32: A simple terminal UI library
Safe HaskellNone
LanguageHaskell2010

Graphics.Vty.Output.Interface

Description

This module provides an abstract interface for performing terminal output. The only user-facing part of this API is Output.

Synopsis

Documentation

data Output Source #

The Vty terminal output interface.

Constructors

Output 

Fields

  • terminalID :: String

    Text identifier for the output device. Used for debugging.

  • releaseTerminal :: IO ()

    Release the terminal just prior to application exit and reset it to its state prior to application startup.

  • reserveDisplay :: IO ()

    Clear the display and initialize the terminal to some initial display state.

    The expectation of a program is that the display starts in some The initial state. initial state would consist of fixed values:

    • cursor at top left
    • UTF-8 character encoding
    • drawing characteristics are the default
  • releaseDisplay :: IO ()

    Return the display to the state before reserveDisplay If no previous state then set the display state to the initial state.

  • setDisplayBounds :: (Int, Int) -> IO ()

    Sets the current display bounds (width, height).

  • displayBounds :: IO DisplayRegion

    Returns the current display bounds.

  • outputByteBuffer :: ByteString -> IO ()

    Output the bytestring to the terminal device.

  • contextColorCount :: Int

    Specifies the maximum number of colors supported by the context.

  • supportsCursorVisibility :: Bool

    Specifies whether the cursor can be shown / hidden.

  • supportsMode :: Mode -> Bool

    Indicates support for terminal modes for this output device.

  • setMode :: Mode -> Bool -> IO ()

    Enables or disables a mode (does nothing if the mode is unsupported).

  • getModeStatus :: Mode -> IO Bool

    Returns whether a mode is enabled.

  • assumedStateRef :: IORef AssumedState
     
  • mkDisplayContext :: Output -> DisplayRegion -> IO DisplayContext

    Acquire display access to the given region of the display. Currently all regions have the upper left corner of (0,0) and the lower right corner at (max displayWidth providedWidth, max displayHeight providedHeight)

  • ringTerminalBell :: IO ()

    Ring the terminal bell if supported.

  • supportsBell :: IO Bool

    Returns whether the terminal has an audio bell feature.

  • supportsItalics :: IO Bool

    Returns whether the terminal supports italicized text.

    This is terminal-dependent and should make a best effort to determine whether this feature is supported, but even if the terminal advertises support (e.g. via terminfo) that might not be a reliable indicator of whether the feature will work as desired.

  • supportsStrikethrough :: IO Bool

    Returns whether the terminal supports strikethrough text.

    This is terminal-dependent and should make a best effort to determine whether this feature is supported, but even if the terminal advertises support (e.g. via terminfo) that might not be a reliable indicator of whether the feature will work as desired.

data DisplayContext Source #

Constructors

DisplayContext 

Fields

data Mode Source #

Modal terminal features that can be enabled and disabled.

Constructors

Mouse

Mouse mode (whether the terminal is configured to provide mouse input events)

BracketedPaste

Paste mode (whether the terminal is configured to provide events on OS pastes)

Focus

Focus-in/focus-out events (whether the terminal is configured to provide events on focus change)

Hyperlink

Hyperlink mode via the withURL attribute modifier (see https://gist.github.com/egmontkob/eb114294efbcd5adb1944c9f3cb5feda). Note that this may not work gracefully in all terminal emulators so be sure to test this mode with the terminals you intend to support. It is off by default.

Instances

Instances details
Eq Mode Source # 
Instance details

Defined in Graphics.Vty.Output.Interface

Methods

(==) :: Mode -> Mode -> Bool #

(/=) :: Mode -> Mode -> Bool #

Read Mode Source # 
Instance details

Defined in Graphics.Vty.Output.Interface

Show Mode Source # 
Instance details

Defined in Graphics.Vty.Output.Interface

Methods

showsPrec :: Int -> Mode -> ShowS #

show :: Mode -> String #

showList :: [Mode] -> ShowS #

outputPicture :: DisplayContext -> Picture -> IO () Source #

Displays the given Picture.

  1. The image is cropped to the display size.
  2. Converted into a sequence of attribute changes and text spans.
  3. The cursor is hidden.
  4. Serialized to the display.
  5. The cursor is then shown and positioned or kept hidden.

limitAttrForDisplay :: Output -> Attr -> Attr Source #

Not all terminals support all display attributes. This filters a display attribute to what the given terminal can display.