Appearance of lines on the trajectory of an animated object

Kamiam

Hello, I have put an image in the background (on a graphicsView) and I want to move some coloured cubes on it. Unfortunately lines appear on the path.

Here is my code below :

animation = new QPropertyAnimation(ui->Cube1, "geometry");
    animation->setDuration(10000);
    animation->setStartValue(ui->Cube1->geometry());
    animation->setEndValue(QRect(600,700,60,60));
    QEasingCurve curve;
    curve.setType(QEasingCurve::InQuad);
    animation->setEasingCurve(curve);
    animation->start();

Do you know how to solve this problem?

Thank you

Chris Kawa

One of the common causes for this problem is drawing outside of your item's bounding box e.g. with a code like

painter->fillRect(rect, color);

where rect is the bounding box given as a parameter to the drawing event callback. The right/bottom edge of the rectangle lies out of it, so you need to adjust for it when drawing e.g.

painter->fillRect(rect.adjusted(0,0,-1,-1), color);