Qt-interest Archive, July 2007
Performance issue with QGraphicsView Framework
Message 1 in thread
Hi,
I am seeing a major performance hit using the QGraphicsFramework.
Below is a code that showcases the problem.
I have created 200 items. Once I select all of them and move around the
canvas, response is very slow.
Is there anything that I am doing wrong or is there a different approach
to do this ?
int main(int argc, char** argv)
{
QApplication app(argc,argv);
QGraphicsScene *scene = new QGraphicsScene();
scene->setSceneRect(QRectF(0,0,2500,2500));
QGraphicsView m_view(scene);
m_view.setDragMode(QGraphicsView::RubberBandDrag);
m_view.show();
for(int i = 0 ; i < 200 ; i++)
{
QGraphicsRectItem *item = new QGraphicsRectItem(QRectF(-50, -50,
100,100), NULL, scene);
item->setFlag(QGraphicsItem::ItemIsMovable);
item->setFlag(QGraphicsItem::ItemIsSelectable);
item->setPos(i+100 + 10 * i, i+100 + 10 * i);
}
return app.exec();
}
Regards
Prateek
