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    proton_screen_monitor

    Native screen and display queries plus hot-plug events for MoonBit on Windows, Linux, and macOS.

    screen
    display
    monitor
    native
    windows
    linux
    macos
    Download zip
    Version
    0.2.10
    License
    Apache-2.0
    Repository
    Last updated
    2 hours ago
    Downloads
    6K

    Dependencies

    #proton_screen_monitor

    Native screen and display queries plus hot-plug events for MoonBit on Windows, Linux, and macOS.

    The module mirrors Electron's screen module:

    • ScreenMonitor::displays() — screen.getAllDisplays()
    • ScreenMonitor::primary_display() — screen.getPrimaryDisplay()
    • ScreenMonitor::display_nearest_point(x, y) — screen.getDisplayNearestPoint(...)
    • getDisplayMatching(rect) — display with the greatest rectangle overlap
    • ScreenMonitor::cursor_point() — screen.getCursorScreenPoint()
    • DisplayAdded / DisplayRemoved / DisplayMetricsChanged events — screen.on('display-added' | 'display-removed' | 'display-metrics-changed')

    Coordinates are physical pixels in a top-left origin. On Linux the backend uses X11 + RandR; a Wayland-only session reports BackendUnavailable for watching while polling queries remain available through XWayland when present. The module is published on Proton's shared workspace version.

    ScreenMonitorError

    source
    pub(all) suberror ScreenMonitorError {
      BackendUnavailable(detail~ : String)
      OperationFailed(operation~ : String, detail~ : String)
      Empty
    } derive(Eq)

    ScreenMonitorError::equal

    source

    ScreenMonitorError::not_equal

    source

    ScreenMonitorError::output

    source
    fn ScreenMonitorError::output(self : ScreenMonitorError, logger : &Logger) -> Unit

    ScreenMonitorError::to_string

    source
    fn ScreenMonitorError::to_string(self : ScreenMonitorError) -> String

    DisplayInfo

    source
    pub struct DisplayInfo {
      id : Int
      bounds : Rect
      work_area : Rect
      scale_factor : Double
      is_primary : Bool
    } derive(Eq, 
    Debug    )

    A display geometry snapshot mirroring Electron's Display.

    DisplayInfo::equal

    source
    fn DisplayInfo::equal(DisplayInfo, DisplayInfo) -> Bool

    DisplayInfo::not_equal

    source
    fn DisplayInfo::not_equal(x : DisplayInfo, y : DisplayInfo) -> Bool

    DisplayInfo::to_repr

    source

    DisplayWire

    source

    DisplaysWire

    source
    type DisplaysWire derive(
    FromJson    )

    Wire shapes produced by the native backend's JSON payloads.

    DisplaysWire::from_json

    source

    Point

    source
    pub struct Point {
      x : Int
      y : Int
    } derive(Eq, 
    Debug    )

    A point in the root (physical pixel) coordinate space.

    Point::equal

    source
    fn Point::equal(Point, Point) -> Bool

    Point::not_equal

    source
    fn Point::not_equal(x : Point, y : Point) -> Bool

    Point::to_repr

    source

    PointWire

    source

    Rect

    source
    pub struct Rect {
      x : Int
      y : Int
      width : Int
      height : Int
    } derive(Eq, 
    Debug    )

    A rectangle in physical pixel coordinates with the top-left origin shared across the facade.

    Rect::equal

    source
    fn Rect::equal(Rect, Rect) -> Bool

    Rect::not_equal

    source
    fn Rect::not_equal(x : Rect, y : Rect) -> Bool

    Rect::to_repr

    source

    ScreenMonitor

    source
    pub struct ScreenMonitor {
      // private fields
    }

    ScreenMonitor::ScreenMonitor

    source
    fn ScreenMonitor::ScreenMonitor() -> ScreenMonitor raise ScreenMonitorError

    Creates a new screen monitor handle. The native backend is verified during creation so an unavailable platform surfaces immediately as BackendUnavailable.

    ScreenMonitor::cursor_point

    source
    fn ScreenMonitor::cursor_point(self : ScreenMonitor) -> Point raise ScreenMonitorError

    Returns the current cursor position in physical pixels with the top-left origin. Corresponds to Electron's screen.getCursorScreenPoint().

    ScreenMonitor::destroy

    source
    fn ScreenMonitor::destroy(self : ScreenMonitor) -> Unit

    Releases the native backend and tears the watch thread down. Idempotent.

    ScreenMonitor::display_nearest_point

    source
    fn ScreenMonitor::display_nearest_point(self : ScreenMonitor, x : Int, y : Int) -> DisplayInfo raise ScreenMonitorError

    Returns the display that is nearest to the given point, preferring a display that actually contains the point. Corresponds to Electron's screen.getDisplayNearestPoint(point).

    ScreenMonitor::display_thumbnail

    source
    fn ScreenMonitor::display_thumbnail(_self : ScreenMonitor, display_id : Int, width : Int, height : Int) -> Bytes

    Captures a display thumbnail as a BMP data URL. An empty byte string means that capture is unavailable or was denied by the operating system.

    ScreenMonitor::displays

    source

    Returns every connected display, with the primary display listed first. Corresponds to Electron's screen.getAllDisplays().

    ScreenMonitor::drain_events

    source

    Drains every pending event from the queue. Returns an empty array when no event is pending; never raises for an empty queue.

    ScreenMonitor::primary_display

    source
    fn ScreenMonitor::primary_display(self : ScreenMonitor) -> DisplayInfo raise ScreenMonitorError

    Returns the primary display. Corresponds to Electron's screen.getPrimaryDisplay(); raises Empty when no display is connected.

    ScreenMonitor::start_watching

    source
    fn ScreenMonitor::start_watching(self : ScreenMonitor) -> Unit raise ScreenMonitorError

    Starts the event watch backend. The backend is best-effort: a platform that cannot watch (for example Linux without an X11 display or RandR) records the failure on the native side and returns BackendUnavailable, leaving polling queries fully usable.

    ScreenMonitor::stop_watching

    source
    fn ScreenMonitor::stop_watching(self : ScreenMonitor) -> Unit raise ScreenMonitorError

    Stops the event watch backend and joins its thread. Idempotent.

    ScreenMonitor::window_sources_json

    source
    fn ScreenMonitor::window_sources_json(_self : ScreenMonitor, width : Int, height : Int) -> Bytes

    Returns the current native window source snapshot as JSON. The payload is consumed by the desktop-capturer extension; unsupported platforms return a structured supported: false payload.

    ScreenMonitorEvent

    source
    pub enum ScreenMonitorEvent {
      DisplayAdded
      DisplayRemoved
      DisplayMetricsChanged
    } derive(Eq, 
    Debug    )

    Display topology events delivered by the watch backend, mirroring Electron's screen module events.

    ScreenMonitorEvent::equal

    source

    ScreenMonitorEvent::not_equal

    source

    ScreenMonitorEvent::to_repr

    source

    State

    source
    pub type State

    Source Files

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