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How to replace the deprecated function `QWheelEvent::delta()` in the zoom in / zoom out function?

I was using the delta() function from the QWheelEvent class to achieve the zoom in, zoom out. now it is deprecated , and they advise in the documentation to use pixelDelta() or angleDelta() instead, but they are QPoint objects!

can anybody please tell me how to replace this deprecated function with another ones?

void MapView::wheelEvent(QWheelEvent *event)
    if(event->delta()>0)
        if(m_scale < MAX_SCALE)
            std::cout << m_scale << std::endl;
            this->scale(ZOOM_STEP, ZOOM_STEP);
            m_scale *= ZOOM_STEP;
    else if(event->delta() < 0)
        if(m_scale >= MIN_SCALE)
            std::cout << m_scale << std::endl;
            this->scale(1/ZOOM_STEP, 1/ZOOM_STEP);
            m_scale *= 1/ZOOM_STEP;
The documentation of angleDelta says that angleDelta().y() will return the angle by which the vertical mouse wheel was rotated and angleDelta().x() will return the angle by which the horizontal mouse wheel was rotated.
For zooming I'm assuming you will want to use vertical scrolling, so changing the conditions accordingly gives:
void MapView::wheelEvent(QWheelEvent *event)
    if(event->angleDelta().y() > 0)
        if(m_scale < MAX_SCALE)
            std::cout << m_scale << std::endl;
            this->scale(ZOOM_STEP, ZOOM_STEP);
            m_scale *= ZOOM_STEP;
    else if(event->angleDelta().y() < 0)
        if(m_scale >= MIN_SCALE)
            std::cout << m_scale << std::endl;
            this->scale(1/ZOOM_STEP, 1/ZOOM_STEP);
            m_scale *= 1/ZOOM_STEP;
                NB Qt docs clarify the horizontal/vertical QPoint structure 5.15, but if you're like me and are using, say, 5.9 they do not (5.12 has the same doc. issue).  So if you're, say, using CentOS 7 and Qt Creator's local help docs you're not crazy and you didn't miss something obvious.
– eclarkso
                Jun 8, 2022 at 13:44
        
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