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50
51#include "paintedwindow.h"
52
53#include <QGuiApplication>
54#include <QOpenGLContext>
55#include <QOpenGLPaintDevice>
56#include <QPainter>
57#include <QPainterPath>
58#include <QScreen>
59#include <QTimer>
60
61#include <qmath.h>
62
63PaintedWindow::PaintedWindow()
64{
65 QSurfaceFormat format;
66 format.setStencilBufferSize(8);
67 format.setSamples(4);
68
69 setSurfaceType(QWindow::OpenGLSurface);
70 setFlags(Qt::Window | Qt::WindowTitleHint | Qt::WindowSystemMenuHint | Qt::WindowMinMaxButtonsHint | Qt::WindowCloseButtonHint);
71 setFormat(format);
72
73 create();
74
75 m_context = new QOpenGLContext(this);
76 m_context->setFormat(format);
77 m_context->create();
78
79 m_animation = new QPropertyAnimation(this, "rotation");
80 m_animation->setStartValue(qreal(0));
81 m_animation->setEndValue(qreal(1));
82 m_animation->setDuration(500);
83
84 QRect screenGeometry = screen()->availableGeometry();
85
86 QPoint center = screenGeometry.center();
87 QRect windowRect = screen()->isLandscape(orientation: screen()->orientation()) ? QRect(0, 0, 640, 480) : QRect(0, 0, 480, 640);
88 setGeometry(QRect(center - windowRect.center(), windowRect.size()));
89
90 m_rotation = 0;
91
92 reportContentOrientationChange(orientation: screen()->orientation());
93
94 m_targetOrientation = contentOrientation();
95 m_nextTargetOrientation = Qt::PrimaryOrientation;
96
97 connect(sender: screen(), signal: &QScreen::orientationChanged, receiver: this, slot: &PaintedWindow::orientationChanged);
98 connect(sender: m_animation, signal: &QAbstractAnimation::finished, receiver: this, slot: &PaintedWindow::rotationDone);
99 connect(sender: this, signal: &PaintedWindow::rotationChanged, receiver: this, slot: QOverload<>::of(ptr: &PaintedWindow::paint));
100}
101
102void PaintedWindow::exposeEvent(QExposeEvent *)
103{
104 if (isExposed())
105 paint();
106}
107
108void PaintedWindow::mousePressEvent(QMouseEvent *)
109{
110 Qt::ScreenOrientation o = contentOrientation();
111 switch (o) {
112 case Qt::LandscapeOrientation:
113 orientationChanged(newOrientation: Qt::PortraitOrientation);
114 break;
115 case Qt::PortraitOrientation:
116 orientationChanged(newOrientation: Qt::InvertedLandscapeOrientation);
117 break;
118 case Qt::InvertedLandscapeOrientation:
119 orientationChanged(newOrientation: Qt::InvertedPortraitOrientation);
120 break;
121 case Qt::InvertedPortraitOrientation:
122 orientationChanged(newOrientation: Qt::LandscapeOrientation);
123 break;
124 default:
125 Q_ASSERT(false);
126 }
127
128 paint();
129}
130
131void PaintedWindow::orientationChanged(Qt::ScreenOrientation newOrientation)
132{
133 if (contentOrientation() == newOrientation)
134 return;
135
136 if (m_animation->state() == QAbstractAnimation::Running) {
137 m_nextTargetOrientation = newOrientation;
138 return;
139 }
140
141 QRect rect(0, 0, width(), height());
142
143 m_prevImage = QImage(width(), height(), QImage::Format_ARGB32_Premultiplied);
144 m_nextImage = QImage(width(), height(), QImage::Format_ARGB32_Premultiplied);
145 m_prevImage.fill(pixel: 0);
146 m_nextImage.fill(pixel: 0);
147
148 QPainter p;
149 p.begin(&m_prevImage);
150 p.setTransform(transform: screen()->transformBetween(a: contentOrientation(), b: screen()->orientation(), target: rect));
151 paint(painter: &p, rect: screen()->mapBetween(a: contentOrientation(), b: screen()->orientation(), rect));
152 p.end();
153
154 p.begin(&m_nextImage);
155 p.setTransform(transform: screen()->transformBetween(a: newOrientation, b: screen()->orientation(), target: rect));
156 paint(painter: &p, rect: screen()->mapBetween(a: newOrientation, b: screen()->orientation(), rect));
157 p.end();
158
159 m_deltaRotation = screen()->angleBetween(a: newOrientation, b: contentOrientation());
160 if (m_deltaRotation > 180)
161 m_deltaRotation = 180 - m_deltaRotation;
162
163 m_targetOrientation = newOrientation;
164 m_animation->start();
165}
166
167void PaintedWindow::rotationDone()
168{
169 reportContentOrientationChange(orientation: m_targetOrientation);
170 if (m_nextTargetOrientation != Qt::PrimaryOrientation) {
171 Q_ASSERT(m_animation->state() != QAbstractAnimation::Running);
172 orientationChanged(newOrientation: m_nextTargetOrientation);
173 m_nextTargetOrientation = Qt::PrimaryOrientation;
174 }
175}
176
177void PaintedWindow::setRotation(qreal r)
178{
179 if (r != m_rotation) {
180 m_rotation = r;
181 emit rotationChanged(rotation: r);
182 }
183}
184
185void PaintedWindow::paint()
186{
187 m_context->makeCurrent(surface: this);
188
189 QRect rect(0, 0, width() * devicePixelRatio(), height() * devicePixelRatio());
190
191 QOpenGLPaintDevice device(size() * devicePixelRatio());
192 QPainter painter(&device);
193
194 QPainterPath path;
195 path.addEllipse(rect);
196 painter.setCompositionMode(QPainter::CompositionMode_Source);
197 painter.fillRect(r: rect, c: Qt::transparent);
198 painter.setCompositionMode(QPainter::CompositionMode_SourceOver);
199 painter.fillPath(path, brush: Qt::blue);
200
201 if (contentOrientation() != m_targetOrientation) {
202 painter.setRenderHint(hint: QPainter::SmoothPixmapTransform);
203 painter.save();
204 painter.translate(dx: width() / 2, dy: height() / 2);
205 painter.rotate(a: m_deltaRotation * m_rotation);
206 painter.translate(dx: -width() / 2, dy: -height() / 2);
207 painter.drawImage(x: 0, y: 0, image: m_prevImage);
208 painter.restore();
209 painter.translate(dx: width() / 2, dy: height() / 2);
210 painter.rotate(a: m_deltaRotation * m_rotation - m_deltaRotation);
211 painter.translate(dx: -width() / 2, dy: -height() / 2);
212 painter.setOpacity(m_rotation);
213 painter.drawImage(x: 0, y: 0, image: m_nextImage);
214 } else {
215 QRect mapped = screen()->mapBetween(a: contentOrientation(), b: screen()->orientation(), rect);
216
217 painter.setTransform(transform: screen()->transformBetween(a: contentOrientation(), b: screen()->orientation(), target: rect));
218 paint(painter: &painter, rect: mapped);
219 painter.end();
220 }
221
222 m_context->swapBuffers(surface: this);
223}
224
225void PaintedWindow::paint(QPainter *painter, const QRect &rect)
226{
227 painter->setRenderHint(hint: QPainter::Antialiasing);
228 QFont font;
229 font.setPixelSize(64);
230 painter->setFont(font);
231 painter->drawText(r: rect, flags: Qt::AlignCenter, text: "Hello");
232}
233

source code of qtbase/examples/opengl/paintedwindow/paintedwindow.cpp