widget/nsIScreenManager.idl

   1 /* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
   2  *
   3  * This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "nsISupports.idl"
   8 #include "nsIScreen.idl"
   9
  10 [scriptable, uuid(1C195990-FF9E-412B-AFE7-67D1C660BB27)]
  11 interface nsIScreenManager : nsISupports
  12 {
  13     //
  14     // Returns the screen that contains the rectangle. If the rect overlaps
  15     // multiple screens, it picks the screen with the greatest area of intersection.
  16     //
  17     // The coordinates are in pixels (not twips) and in screen coordinates.
  18     //
  19   nsIScreen screenForRect ( in long left, in long top, in long width, in long height ) ;
  20
  21     // The screen with the menubar/taskbar. This shouldn't be needed very
  22     // often.
  23   readonly attribute nsIScreen primaryScreen;
  24
  25     // Holds the number of screens that are available
  26   readonly attribute unsigned long numberOfScreens;
  27
  28     // The default DPI scaling factor of the screen environment (number of
  29     // screen pixels corresponding to 1 CSS px, at the default zoom level).
  30     //
  31     // This is currently fixed at 1.0 on most platforms, but varies on Windows
  32     // if the "logical DPI" scaling option in the Display control panel is set
  33     // to a value other than 100% (e.g. 125% or 150% are increasingly common
  34     // defaults on laptops with high-dpi screens). See bug 851520.
  35     //
  36     // NOTE that on OS X, this does -not- reflect the "backing scale factor"
  37     // used to support Retina displays, which is a per-display property,
  38     // not a system-wide scaling factor. The default ratio of CSS pixels to
  39     // Cocoa points remains 1:1, even on a Retina screen where one Cocoa point
  40     // corresponds to two device pixels. (This is exposed via other APIs:
  41     // see window.devicePixelRatio).
  42     //
  43     // NOTE also that on Linux, this does -not- currently reflect changes
  44     // to the system-wide (X11 or Gtk2) DPI value, as Firefox does not yet
  45     // honor these settings. See bug 798362 and bug 712898.
  46   readonly attribute float systemDefaultScale;
  47
  48     // Returns the nsIScreen instance for the given native widget pointer;
  49     // the pointer is specific to the particular widget implementation,
  50     // and is generally of the same type that NS_NATIVE_WINDOW is.
  51   [noscript] nsIScreen screenForNativeWidget ( in voidPtr nativeWidget );
  52 };
  53
  54
  55 %{ C++
  56
  57 %}