figure out how to get Wacom tablet proximity position; deliver to window

bool QWindowSystemInterface::handleTabletEnterLeaveProximityEvent(QWindow *window, ulong timestamp, const QPointingDevice *device,
                                                                  bool inProximity, const QPointF &local, const QPointF &global,
                                                                  Qt::MouseButtons buttons, int xTilt, int yTilt,
                                                                  qreal tangentialPressure, qreal rotation, int z,
                                                                  Qt::KeyboardModifiers modifiers)
{
    Q_UNUSED(window);
    Q_UNUSED(local);
    Q_UNUSED(global);
    Q_UNUSED(buttons);
    Q_UNUSED(xTilt);
    Q_UNUSED(yTilt);
    Q_UNUSED(tangentialPressure);
    Q_UNUSED(rotation);
    Q_UNUSED(z);
    Q_UNUSED(modifiers);
    return inProximity
        ? handleWindowSystemEvent<QWindowSystemInterfacePrivate::TabletEnterProximityEvent>(timestamp, device)
        : handleWindowSystemEvent<QWindowSystemInterfacePrivate::TabletLeaveProximityEvent>(timestamp, device);
}

    class TabletEnterProximityEvent : public PointerEvent {
    public:
        // TODO store more info: position and whatever else we can get on most platforms
        TabletEnterProximityEvent(ulong time, const QPointingDevice *device)
            : PointerEvent(nullptr, time, TabletEnterProximity, Qt::NoModifier, device) { }
    };

    class TabletLeaveProximityEvent : public PointerEvent {
    public:
        // TODO store more info: position and whatever else we can get on most platforms
        TabletLeaveProximityEvent(ulong time, const QPointingDevice *device)
            : PointerEvent(nullptr, time, TabletLeaveProximity, Qt::NoModifier, device) { }
    };