Zoom problem in QGraphicsView

[ivanicy]

Hello!

I am trying to develope the zoom function in a QGraphicsView.

I have this code:

double scaleFactor = 1.15;
double currentScale = 1.0;
double scaleMin = 1.00;

void imageView::wheelEvent(QWheelEvent *event) {
    /* MODO POR DEFECTO (ZOOM) ****************************************************************************** */
    if (graphicMode == ZOOM_MODE) {
    //if (sceneMode == NoMode) {
        this->setTransformationAnchor(QGraphicsView::AnchorUnderMouse);
        if (event->delta() > 0) {
            this->scale(scaleFactor, scaleFactor);
            currentScale *= scaleFactor;
        } else if (currentScale > scaleMin && (currentScale / scaleFactor) >= scaleMin ) {
            this->scale(1/scaleFactor, 1/scaleFactor);
            currentScale /= scaleFactor;
        } else if (currentScale <= scaleMin) {
            //currentScale = scaleMin;
        }
        this->centerOn(event->pos());

        _pan = false;
    }
    /* ****************************************************************************************************** */
}

I have a problem with this sequence:

1. I do zoom in in the image.
2. I move the mouse cursor position.
3. When I do zoom out, the zoom doesn't do it correctly. The position of the zoom out isn't correct.

What could be the mistake?

Thank you very much!!