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QGraphicsItem moving along path

Is it possible to animate a QGraphicsItem in such a way that it would move along some path within QGraphicsScene / QGraphicsView?

Something like this demo, where white point moves along gear - a closed curve.

If so, then how could it be done?

Solution

  • Found a solution here:

    QGraphicsItem *ball = new QGraphicsEllipseItem(0, 0, 20, 20);

QTimeLine *timer = new QTimeLine(5000);
timer->setFrameRange(0, 100);

QGraphicsItemAnimation *animation = new QGraphicsItemAnimation;
animation->setItem(ball);
animation->setTimeLine(timer);

animation->setPosAt(0.f / 200.f, QPointF(0, 0));
animation->setPosAt(10.f / 200.f, QPointF(0, 30));
animation->setPosAt(20.f / 200.f, QPointF(20, 30));
animation->setPosAt(30.f / 200.f, QPointF(20, 20));
animation->setPosAt(40.f / 200.f, QPointF(30, 20));
animation->setPosAt(50.f / 200.f, QPointF(30, 30));
animation->setPosAt(60.f / 200.f, QPointF(40, 30));
animation->setPosAt(70.f / 200.f, QPointF(40, 60));
animation->setPosAt(80.f / 200.f, QPointF(50, 60));
animation->setPosAt(90.f / 200.f, QPointF(50, 0));
animation->setPosAt(100.f / 200.f, QPointF(70, 0));
animation->setPosAt(110.f / 200.f, QPointF(70, 10));
animation->setPosAt(120.f / 200.f, QPointF(80, 10));

QGraphicsScene *scene = new QGraphicsScene();
scene->setSceneRect(0, 0, 250, 250);
scene->addItem(ball);

ui->graphicsView->setScene(scene);

timer->start();