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/****************************************************************************
**
** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:FDL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
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** a written agreement between you and Digia. For licensing terms and
** conditions see http://qt.digia.com/licensing. For further information
** use the contact form at http://qt.digia.com/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: http://www.gnu.org/copyleft/fdl.html.
** $QT_END_LICENSE$
**
****************************************************************************/
/*!
\example sensors/grueplugin
\title Grue Plugin
The Grue plugin example demonstrates the creation of a new sensor type,
a sensor backend and plugin for the sensors library. Related to this example
is the \l{sensors/grueapp}{Grue Application} example.
\tableofcontents
\section1 Grue Sensor Type
The files for this are:
\list
\o gruesensor.h
\o gruesensor_p.h
\o gruesensor.cpp
\endlist
First up is the sensor type. This is the interface for sensors that report
on your likelihood of being eaten by a Grue. Such sensors are very important
to adventurers, particularly if they are going into dark places as this is
where Grues live.
The interface is a simple one. It provides only 1 piece of information, your
chance of being eaten. For the details on how this is property should be
interpreted please see the documentation in gruesensor.cpp.
This example was created using the make_sensor.pl script which can be found in
src/sensors. As such, it contains some generated code that defines the convenience
classes GrueFilter and GrueSensor.
\section1 Grue Sensor Backend
The files for this are:
\list
\o gruesensorimpl.h
\o gruesensorimpl.cpp
\endlist
The Grue sensor needs a backend before it can be used. The backend provided
is rather basic and it relies on some kind of light sensor to work but it
gets the job done. If new hardware that can detect the actual presence of Grues
becomes available a backend could be created that supports this hardware and
applications using the Grue sensor would be able to use it without any changes.
There are a few mandatory parts to a backend. They are the start and stop methods
and the setReading call. The start and stop methods are used to start and stop
any underlying hardware. In the case of this backend they start and stop a
light sensor. In the start method, the backend should be sure to call the
sensorStopped() or sensorBusy() methods if it cannot start.
\snippet ../../examples/sensors/grueplugin/gruesensorimpl.cpp start
The setReading method is needed so that the sensors library knows where the
readings are coming from. This backend has a local copy of the reading so
it passes a pointer to the function.
\snippet ../../examples/sensors/grueplugin/gruesensorimpl.cpp setReading
However it is also possible to pass null to the setReading method in which
case the sensors library will create an instance and return a pointer.
\code
// Create a reading instance for us to use
m_reading = setReading<GrueSensorReading>(0);
\endcode
The Grue sensor backend also supplies some metadata.
The backend checks 2 things, how dark it is and how long you have been in the dark.
It uses the readingChanged() signal to know when to check the light sensor's
value. Once it is dark, it uses a timer to increase your chance of being eaten.
\section1 Grue Sensor Plugin
The files for this are:
\list
\o main.cpp
\endlist
The Grue sensor backend is delivered as a plugin. The plugin has a factory object
that registers the types available and does the actual instantiation of the backend.
\sa {sensors/grueapp}{Grue Application}
*/
/*!
\example sensors/grueapp
\title Grue Application
The Grue application example demonstrates the use of the Grue sensor which
was defined and implemented by the \l{sensors/grueplugin}{Grue Plugin} example.
The Grue application is a commandline application. It is significant to note that
there is no link-time dependency on the Grue plugin. The Grue application uses
the generic access feature of the Sensors API.
\sa {sensors/grueplugin}{Grue Plugin}
*/
/*!
\example sensors/cubehouse
\title Cube House
\image cubehouse.png
The Cube House example demonstrates the use of the accelerometer to drive a camera
to create a pseudo-3D effect. It also demonstrates the use of a filter to smooth
out the accelerometer values.
The accelerometer is created and the filter is added.
\snippet ../../examples/sensors/cubehouse/view.cpp accelerometer
When new values are available, the view is recalculated.
\snippet ../../examples/sensors/cubehouse/view.cpp accelerometer2
The filter is defined like this.
\snippet ../../examples/sensors/cubehouse/view.cpp smoothed
*/
/*!
\example sensors/sensor_explorer
\title Sensor Explorer
\image sensor_explorer.png
The Sensor Explorer example demonstrates how to read the meta-data of available sensors.
It was designed as a debugging aid.
*/
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