widget/qt/nsScreenManagerQt.cpp

   1 /* This Source Code Form is subject to the terms of the Mozilla Public
   2  * License, v. 2.0. If a copy of the MPL was not distributed with this
   3  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   4
   5 #include <QGuiApplication>
   6 #include <QScreen>
   7
   8 #include "nsScreenManagerQt.h"
   9 #include "nsScreenQt.h"
  10
  11 nsScreenManagerQt::nsScreenManagerQt()
  12 {
  13     mInitialized = false;
  14     desktop = 0;
  15     screens = 0;
  16 }
  17
  18 nsScreenManagerQt::~nsScreenManagerQt()
  19 {
  20     delete [] screens;
  21 }
  22
  23 // addref, release, QI
  24 NS_IMPL_ISUPPORTS(nsScreenManagerQt, nsIScreenManager)
  25
  26 void nsScreenManagerQt::init()
  27 {
  28     if (mInitialized)
  29         return;
  30
  31     nScreens = QGuiApplication::screens().size();
  32     screens = new nsCOMPtr<nsIScreen>[nScreens];
  33
  34     for (int i = 0; i < nScreens; ++i)
  35         screens[i] = new nsScreenQt(i);
  36     mInitialized = true;
  37 }
  38
  39 //
  40 // ScreenForRect
  41 //
  42 // Returns the screen that contains the rectangle. If the rect overlaps
  43 // multiple screens, it picks the screen with the greatest area of intersection.
  44 //
  45 // The coordinates are in pixels (not twips) and in screen coordinates.
  46 //
  47 NS_IMETHODIMP
  48 nsScreenManagerQt::ScreenForRect(int32_t inLeft, int32_t inTop,
  49                                  int32_t inWidth, int32_t inHeight,
  50                                  nsIScreen **outScreen)
  51 {
  52     if (!mInitialized)
  53         init();
  54
  55     QRect r(inLeft, inTop, inWidth, inHeight);
  56     int best = 0;
  57     int area = 0;
  58     for (int i = 0; i < nScreens; ++i) {
  59         const QRect& rect = QGuiApplication::screens()[i]->geometry();
  60         QRect intersection = r&rect;
  61         int a = intersection.width()*intersection.height();
  62         if (a > area) {
  63             best = i;
  64             area = a;
  65         }
  66     }
  67
  68     NS_IF_ADDREF(*outScreen = screens[best]);
  69     return NS_OK;
  70 }
  71
  72 NS_IMETHODIMP
  73 nsScreenManagerQt::ScreenForId(uint32_t aId, nsIScreen** aOutScreen)
  74 {
  75     if (!mInitialized) {
  76         init();
  77     }
  78
  79     if (aId < nScreens) {
  80         NS_IF_ADDREF(*aOutScreen = screens[aId]);
  81         return NS_OK;
  82     }
  83
  84     return NS_ERROR_FAILURE;
  85 }
  86
  87 //
  88 // GetPrimaryScreen
  89 //
  90 // The screen with the menubar/taskbar. This shouldn't be needed very
  91 // often.
  92 //
  93 NS_IMETHODIMP
  94 nsScreenManagerQt::GetPrimaryScreen(nsIScreen **aPrimaryScreen)
  95 {
  96     if (!desktop)
  97         init();
  98
  99     NS_IF_ADDREF(*aPrimaryScreen = screens[0]);
 100     return NS_OK;
 101 }
 102
 103 //
 104 // GetNumberOfScreens
 105 //
 106 // Returns how many physical screens are available.
 107 //
 108 NS_IMETHODIMP
 109 nsScreenManagerQt::GetNumberOfScreens(uint32_t *aNumberOfScreens)
 110 {
 111     if (!desktop)
 112         init();
 113
 114     *aNumberOfScreens = nScreens;
 115     return NS_OK;
 116 }
 117
 118 NS_IMETHODIMP
 119 nsScreenManagerQt::GetSystemDefaultScale(float *aDefaultScale)
 120 {
 121     *aDefaultScale = 1.0f;
 122     return NS_OK;
 123 }
 124
 125 NS_IMETHODIMP
 126 nsScreenManagerQt::ScreenForNativeWidget(void *aWidget, nsIScreen **outScreen)
 127 {
 128     // I don't know how to go from GtkWindow to nsIScreen, especially
 129     // given xinerama and stuff, so let's just do this
 130     QRect rect(0, 0, 1, 1);
 131     return ScreenForRect(rect.x(), rect.y(), rect.width(), rect.height(), outScreen);
 132 }