Russian Qt Forum

#include <QtGui>

class MyClass : public QWidget{
public:
  MyClass(){

  }
  void paintEvent(QPaintEvent* event)
  {
    int i=0;

    QTime time;
    time.start();

    for(i=0;i<100;i++){
        QPainter p(this);
        p.setRenderHint(QPainter::Antialiasing,true);
        p.setPen(QPen(Qt::blue,2,Qt::SolidLine));
        p.drawLine(0,0,640,480);
        p.end();
      }

    qDebug()<<"paint"<< " mc = " <<time.elapsed();
  }
};

int main(int argc, char* argv[]){
  QApplication app(argc, argv);

  MyClass* myClass = new MyClass();

  myClass->resize(640,480);
  myClass->show();

  return app.exec();
}

    QTime time;
    time.start();

    QPainter p(this);
    p.setRenderHint(QPainter::Antialiasing,true);
    p.setPen(QPen(Qt::blue,2,Qt::SolidLine));

    QPainterPath path;

    for(int i=0;i<100;i++){
        path.moveTo(0,0);
        path.lineTo(640,480);
     }

    p.drawPath(path);
    p.end();

    qDebug()<< "paint"<< " mc = " <<time.elapsed();

QPainter painter(this);
for (int i = 0; i < 100; ++i) {
   painter.drawLine(.....);
}

QPainter painter(this);
QPainterPath path
for (int i = 0; i < 100; ++i) {
   path.moveTo(...);
   path.lineTo(...);
}

painter.drawPath(path);

"path = 0, draw time = 0.194. Press a key to redraw" 
"path = -1, draw time = 0.377. Press a key to redraw" 
"path = 0, draw time = 0.194. Press a key to redraw" 
"path = -1, draw time = 0.388. Press a key to redraw" 
"path = 0, draw time = 0.192. Press a key to redraw" 
"path = -1, draw time = 0.385. Press a key to redraw" 

"path = 0, draw time = 0.771. Press a key to redraw" 
"path = -1, draw time = 0.143. Press a key to redraw" 
"path = 0, draw time = 0.745. Press a key to redraw" 
"path = -1, draw time = 0.141. Press a key to redraw" 
"path = 0, draw time = 0.709. Press a key to redraw" 
"path = -1, draw time = 0.14. Press a key to redraw"

"path = 0, draw time = 0.236. Press a key to redraw"
"path = 1, draw time = 0.263. Press a key to redraw"
"path = 0, draw time = 0.26. Press a key to redraw"
"path = 1, draw time = 0.244. Press a key to redraw"
"path = 0, draw time = 0.25. Press a key to redraw"
"path = 1, draw time = 0.252. Press a key to redraw"

"path = 0, draw time = 0.562. Press a key to redraw"
"path = 1, draw time = 0.545. Press a key to redraw"
"path = 0, draw time = 0.556. Press a key to redraw"
"path = 1, draw time = 0.565. Press a key to redraw"
"path = 0, draw time = 0.549. Press a key to redraw"
"path = 1, draw time = 0.57. Press a key to redraw"

QPainter::drawText 3.9 - 4.5
QStaticText        4.2 - 5
QPainterPath       ~1.9