问为什么QPainter标度(化妆品)点在一个轴上，尽管它们不应该受到影响？

EN

void RenderArea::paintEvent(QPaintEvent* /* event */)
{
    const qreal scaleFactor = 0.01;

    // Define a "unit" square
    std::vector<QPointF> points;
    points.push_back(QPointF(0, 0));
    points.push_back(QPointF(1.0, 0));
    points.push_back(QPointF(1.0, 1.0));
    points.push_back(QPointF(0, 1.0));

    // Build a scaled version of the points
    for (unsigned i = 0; i < points.size(); i++) {
        points[i] *= scaleFactor;
    }

    QPainter painter(this);

    painter.save();

    // Scale the painter so that every square takes 100 pixels
    // in screen space regardless of the scaleFactor:
    painter.scale(100.0 / scaleFactor, 100.0 / scaleFactor);

    QPen pointPen(Qt::blue, 10);
    pointPen.setCosmetic(true);
    painter.setPen(pointPen);
    painter.drawPoints(points.data(), points.size());

    QPen linePen(Qt::red, 5);
    linePen.setCosmetic(true);
    painter.setPen(linePen);
    painter.drawPolyline(points.data(), points.size());

    painter.restore();
}