1// Copyright (C) 2016 The Qt Company Ltd.
2// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
3
4#ifndef QPAINTDEVICEWINDOW_P_H
5#define QPAINTDEVICEWINDOW_P_H
6
7//
8// W A R N I N G
9// -------------
10//
11// This file is not part of the Qt API. It exists purely as an
12// implementation detail. This header file may change from version to
13// version without notice, or even be removed.
14//
15// We mean it.
16//
17
18#include <QtGui/private/qtguiglobal_p.h>
19#include <QtGui/QPaintDeviceWindow>
20#include <QtCore/QCoreApplication>
21#include <QtGui/private/qwindow_p.h>
22#include <QtGui/QPaintEvent>
23
24QT_BEGIN_NAMESPACE
25
26class Q_GUI_EXPORT QPaintDeviceWindowPrivate : public QWindowPrivate
27{
28 Q_DECLARE_PUBLIC(QPaintDeviceWindow)
29
30public:
31 QPaintDeviceWindowPrivate();
32 ~QPaintDeviceWindowPrivate() override;
33
34 virtual void beginPaint(const QRegion &region)
35 {
36 Q_UNUSED(region);
37 }
38
39 virtual void endPaint()
40 {
41 }
42
43 virtual void flush(const QRegion &region)
44 {
45 Q_UNUSED(region);
46 }
47
48 bool paint(const QRegion &region)
49 {
50 Q_Q(QPaintDeviceWindow);
51 QRegion toPaint = region & dirtyRegion;
52 if (toPaint.isEmpty())
53 return false;
54
55 // Clear the region now. The overridden functions may call update().
56 dirtyRegion -= toPaint;
57
58 beginPaint(region: toPaint);
59
60 QPaintEvent paintEvent(toPaint);
61 q->paintEvent(event: &paintEvent);
62
63 endPaint();
64
65 return true;
66 }
67
68 void doFlush(const QRegion &region)
69 {
70 QRegion toFlush = region;
71 if (paint(region: toFlush))
72 flush(region: toFlush);
73 }
74
75 void handleUpdateEvent()
76 {
77 if (dirtyRegion.isEmpty())
78 return;
79 doFlush(region: dirtyRegion);
80 }
81
82 void markWindowAsDirty()
83 {
84 Q_Q(QPaintDeviceWindow);
85 dirtyRegion = QRect(QPoint(0, 0), q->size());
86 }
87
88private:
89 QRegion dirtyRegion;
90};
91
92
93QT_END_NAMESPACE
94
95#endif //QPAINTDEVICEWINDOW_P_H
96

source code of qtbase/src/gui/kernel/qpaintdevicewindow_p.h