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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0
#include <QtGui>
#include "valgrind/callgrind.h"
class View : public QGraphicsView
{
Q_OBJECT
public:
View(QGraphicsScene *scene, QGraphicsItem *item)
: QGraphicsView(scene), _item(item)
{
}
protected:
void paintEvent(QPaintEvent *event)
{
static int n = 0;
if (n)
CALLGRIND_START_INSTRUMENTATION
QGraphicsView::paintEvent(event);
_item->moveBy(1, 1);
if (n)
CALLGRIND_STOP_INSTRUMENTATION
if (++n == 200)
qApp->quit();
}
private:
QGraphicsItem *_item;
};
int main(int argc, char *argv[])
{
QApplication app(argc, argv);
if (argc < 2) {
qDebug("usage: ./%s <numItems>", argv[0]);
return 1;
}
QGraphicsScene scene(-150, -150, 300, 300);
scene.setItemIndexMethod(QGraphicsScene::NoIndex);
QGraphicsRectItem *item = scene.addRect(-50, -50, 100, 100, QPen(Qt::NoPen), QBrush(Qt::blue));
item->setFlag(QGraphicsItem::ItemIsMovable);
for (int i = 0; i < atoi(argv[1]); ++i) {
QGraphicsRectItem *child = scene.addRect(-5, -5, 10, 10, QPen(Qt::NoPen), QBrush(Qt::blue));
child->setPos(-50 + QRandomGenerator::global()->bounded(100), -50 + QRandomGenerator::global()->bounded(100));
child->setParentItem(item);
}
View view(&scene, item);
view.resize(300, 300);
view.show();
return app.exec();
}
#include "main.moc"
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