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/****************************************************************************
**
** Copyright (C) 2019 Luxoft Sweden AB
** Copyright (C) 2018 Pelagicore AG
** Contact: https://www.qt.io/licensing/
**
** This file is part of the documentation of the Luxoft Application Manager.
**
** $QT_BEGIN_LICENSE:FDL-QTAS$
** Commercial License Usage
** Licensees holding valid commercial Qt Automotive Suite licenses may use
** this file in accordance with the commercial license agreement provided
** with the Software or, alternatively, in accordance with the terms
** contained in a written agreement between you and The Qt Company. For
** licensing terms and conditions see https://www.qt.io/terms-conditions.
** For further information use the contact form at https://www.qt.io/contact-us.
**
** GNU Free Documentation License Usage
** Alternatively, this file may be used under the terms of the GNU Free
** Documentation License version 1.3 as published by the Free Software
** Foundation and appearing in the file included in the packaging of
** this file. Please review the following information to ensure
** the GNU Free Documentation License version 1.3 requirements
** will be met: https://www.gnu.org/licenses/fdl-1.3.html.
** $QT_END_LICENSE$
**
****************************************************************************/
/*!
\example applicationmanager/frame-timer
\title Displaying Frame-Rate of System-UI and Applications Example
\image frame-timer-example.png The "FrameTimer" example with two applications running.
\brief How to use FrameTimer to display frame-rate information.
\ingroup applicationmanager-examples
This example shows you how to use the \l FrameTimer component to display frame-rate information
of both System-UI and application windows.
The System-UI is comprised of a column of application icons on the left side and a graph on the top
right side, displaying the average frame-rate of the System-UI itself (actually of System-UI's top-level
Window, to be more precise). If there are no applications running, System-UI's frame rate will mostly
stay at 1 frame per second. That's because a Qt QML application window is only redrawn when needed. If
nothing changed on it, it won't redraw (zero frames per second then). The only reason that System-UI
stays around 1 FPS when there are no apps running is because of the FPS graph itself, which is updated
once every second and thus causes a redraw of the System-UI (an
\l{https://en.wikipedia.org/wiki/Observer_effect_(information_technology)}{Observer effect}).
The Fish application animates (and therefore redraws) at a rate of 25 frames per second. So running it will
instantly raise the frame-rate of System-UI to 25 FPS (frames per second) as well.
The Rabbit application animates at native speed (ie, as fast as the system can or is configured to do, which
is usually 60 FPS). So running it will raise System-UI's FPS further, to 60 FPS.
*/
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