Module: AsciinemaWin::Win32Screen

Extended by:
Fiddle::Importer
Defined in:
lib/asciinema_win/win32_screen.rb

Overview

Reads the live contents (characters + attributes) of the Windows console screen buffer, for the recorder’s frame-capture loop.

This intentionally lives in asciinema_win rather than in the vendored Rich library: it is a recording concern, not a text-formatting one, and keeping it here means re-vendoring an updated Rich can never silently drop it (which is exactly how recording broke before). For the handle and buffer geometry it reuses the public Rich::Win32Console helpers; it only binds the two cell-reading functions Rich does not expose.

See Also:

Class Method Summary collapse

Class Method Details

.capture ⇒ Hash?

Capture the visible region of the console screen buffer.

Returns:

  • (Hash, nil) —

    A snapshot in the shape ScreenBuffer expects, or nil if not on Windows / the console is unavailable. Shape: {

    width:, height:, cursor_x:, cursor_y:,
lines: [ { chars: String, attributes: Array<Integer> }, ... ]

    }



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# File 'lib/asciinema_win/win32_screen.rb', line 44

def capture
  return nil unless Gem.win_platform?

  handle = Rich::Win32Console.stdout_handle
  return nil unless handle

  info = Rich::Win32Console.get_screen_buffer_info(handle)
  return nil unless info

  win = info[:window]
  left = win[:left]
  top = win[:top]
  width = win[:right] - left + 1
  height = win[:bottom] - top + 1
  return nil if width <= 0 || height <= 0

  lines = Array.new(height) do |row|
    read_line(handle, left, top + row, width)
  end

  cursor = info[:cursor_position]
  {
    width: width,
    height: height,
    cursor_x: [cursor[:x] - left, 0].max,
    cursor_y: [cursor[:y] - top, 0].max,
    lines: lines
  }
end