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39
40#include "qrasterwindow.h"
41
42#include <QtGui/private/qpaintdevicewindow_p.h>
43
44#include <QtGui/QBackingStore>
45#include <QtGui/QPainter>
46
47QT_BEGIN_NAMESPACE
48
49/*!
50 \class QRasterWindow
51 \inmodule QtGui
52 \since 5.4
53 \brief QRasterWindow is a convenience class for using QPainter on a QWindow.
54
55 QRasterWindow is a QWindow with a raster-based, non-OpenGL surface. On top of
56 the functionality offered by QWindow, QRasterWindow adds a virtual
57 paintEvent() function and the possibility to open a QPainter on itself. The
58 underlying paint engine will be the raster one, meaning that all drawing will
59 happen on the CPU. For performing accelerated, OpenGL-based drawing, use
60 QOpenGLWindow instead.
61
62 Internally the class is thin wrapper for QWindow and QBackingStore
63 and is very similar to the \l{Raster Window Example}{Raster Window
64 Example} that uses these classes directly.
65
66 \sa QPaintDeviceWindow::paintEvent(), QPaintDeviceWindow::update()
67*/
68
69class QRasterWindowPrivate : public QPaintDeviceWindowPrivate
70{
71 Q_DECLARE_PUBLIC(QRasterWindow)
72public:
73 void beginPaint(const QRegion &region) override
74 {
75 Q_Q(QRasterWindow);
76 const QSize size = q->size();
77 if (backingstore->size() != size) {
78 backingstore->resize(size);
79 markWindowAsDirty();
80 }
81 backingstore->beginPaint(region);
82 }
83
84 void endPaint() override
85 {
86 backingstore->endPaint();
87 }
88
89 void flush(const QRegion &region) override
90 {
91 Q_Q(QRasterWindow);
92 backingstore->flush(region, q);
93 }
94
95 QScopedPointer<QBackingStore> backingstore;
96};
97
98/*!
99 Constructs a new QRasterWindow with \a parent.
100*/
101QRasterWindow::QRasterWindow(QWindow *parent)
102 : QPaintDeviceWindow(*(new QRasterWindowPrivate), parent)
103{
104 setSurfaceType(QSurface::RasterSurface);
105 d_func()->backingstore.reset(new QBackingStore(this));
106}
107
108QRasterWindow::~QRasterWindow()
109{
110 Q_D(QRasterWindow);
111 // Delete backingstore while window is still alive, as it
112 // might need to reference the window in the process
113 d->backingstore.reset(nullptr);
114}
115
116/*!
117 \internal
118*/
119int QRasterWindow::metric(PaintDeviceMetric metric) const
120{
121 Q_D(const QRasterWindow);
122
123 switch (metric) {
124 case PdmDepth:
125 return d->backingstore->paintDevice()->depth();
126 default:
127 break;
128 }
129 return QPaintDeviceWindow::metric(metric);
130}
131
132/*!
133 \internal
134*/
135QPaintDevice *QRasterWindow::redirected(QPoint *) const
136{
137 Q_D(const QRasterWindow);
138 return d->backingstore->paintDevice();
139}
140
141QT_END_NAMESPACE
142