OSX Mavericks coordinate system with multiple monitors @ heterogeneous height is anchored to bottom instead of top

#include <QtGui/QGuiApplication>
#include "qtquick2applicationviewer.h"
#include <QScreen>
#include <QDir>

QString adjustPath(const QString &path)
{
#if defined(Q_OS_IOS)
    if (!QDir::isAbsolutePath(path))
        return QString::fromLatin1("%1/%2")
                .arg(QCoreApplication::applicationDirPath(), path);
#elif defined(Q_OS_MAC)
    if (!QDir::isAbsolutePath(path))
        return QString::fromLatin1("%1/../Resources/%2")
                .arg(QCoreApplication::applicationDirPath(), path);
#elif defined(Q_OS_BLACKBERRY)
    if (!QDir::isAbsolutePath(path))
        return QString::fromLatin1("app/native/%1").arg(path);
#elif !defined(Q_OS_ANDROID)
    QString pathInInstallDir =
            QString::fromLatin1("%1/../%2").arg(QCoreApplication::applicationDirPath(), path);
    if (QFileInfo(pathInInstallDir).exists())
        return pathInInstallDir;
    pathInInstallDir =
            QString::fromLatin1("%1/%2").arg(QCoreApplication::applicationDirPath(), path);
    if (QFileInfo(pathInInstallDir).exists())
        return pathInInstallDir;
#elif defined(Q_OS_ANDROID_NO_SDK)
    return QLatin1String("/data/user/qt/") + path;
#endif
    return path;
}

int main(int argc, char *argv[])
{
    QGuiApplication app(argc, argv);

    /**
    QtQuick2ApplicationViewer viewer;
    viewer.setMainQmlFile(QStringLiteral("qml/Test/main.qml"));
    viewer.showExpanded();
    **/

    QQuickView* mainWindow = new QQuickView();
    mainWindow->setSource(QUrl(adjustPath("qml/Test/main.qml")));
    QRect a = mainWindow->screen()->availableGeometry();
    QRect r = mainWindow->frameGeometry();
    // r.moveCenter(a.center()); // this positions the window higher than center in the smaller screen
    r.moveCenter(a.center() - QPoint(0, mainWindow->screen()->availableGeometry().height() - mainWindow->screen()->virtualGeometry().height())); // this positions the window correctly in the center of the smaller screen
    mainWindow->setPosition(r.topLeft());
    mainWindow->show();

    return app.exec();
}