source: trunk/src/gui/embedded/qmouse_qws.cpp@ 855

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#include "qmouse_qws.h"
#include "qwindowsystem_qws.h"
#include "qscreen_qws.h"
#include "qapplication.h"
#include "qtextstream.h"
#include "qfile.h"
#include "qdebug.h"
#include "qscreen_qws.h"

QT_BEGIN_NAMESPACE

/*!
    \class QWSPointerCalibrationData
    \ingroup qws

    \brief The QWSPointerCalibrationData class is a container for
    mouse calibration data in Qt for Embedded Linux.

    Note that this class is only available in \l{Qt for Embedded Linux}.

    QWSPointerCalibrationData stores device and screen coordinates in
    the devPoints and screenPoints variables, respectively.

    A calibration program should create a QWSPointerCalibrationData
    object, fill the devPoints and screenPoints variables with its
    device and screen coordinates, and pass the object to the mouse
    driver using the QWSMouseHandler::calibrate() function.

    \sa QWSCalibratedMouseHandler, {Mouse Calibration Example}
*/

/*!
    \variable QWSPointerCalibrationData::devPoints
    \brief the raw device coordinates for each value of the Location enum.
*/

/*!
    \variable QWSPointerCalibrationData::screenPoints
    \brief the logical screen coordinates for each value of the Location enum.
*/

/*!
    \enum QWSPointerCalibrationData::Location

    This enum describes the various logical positions that can be
    specified by the devPoints and screenPoints variables.

    \value TopLeft           Index of the top left corner of the screen.
    \value BottomLeft     Index of the bottom left corner of the screen.
    \value BottomRight   Index of the bottom right corner of the screen.
    \value TopRight         Index of the top right corner of the screen.
    \value Center            Index of the center of the screen.
    \value LastLocation   Last index in the pointer arrays.
*/

class QWSMouseHandlerPrivate
{
public:
    QWSMouseHandlerPrivate() : screen(qt_screen) {}

    const QScreen *screen;
};

/*!
    \class QWSMouseHandler
    \ingroup qws

    \brief The QWSMouseHandler class is a base class for mouse drivers in
    Qt for Embedded Linux.

    Note that this class is only available in \l{Qt for Embedded Linux}.

    \l{Qt for Embedded Linux} provides ready-made drivers for several mouse
    protocols, see the \l{Qt for Embedded Linux Pointer Handling}{pointer
    handling} documentation for details. Custom mouse drivers can be
    implemented by subclassing the QWSMouseHandler class and creating
    a mouse driver plugin (derived from QMouseDriverPlugin).
    The default implementation of the QMouseDriverFactory class
    will automatically detect the plugin, and load the driver into the
    server application at run-time using Qt's \l {How to Create Qt
    Plugins}{plugin system}.

    The mouse driver receives mouse events from the system device and
    encapsulates each event with an instance of the QWSEvent class
    which it then passes to the server application (the server is
    responsible for propagating the event to the appropriate
    client). To receive mouse events, a QWSMouseHandler object will
    usually create a QSocketNotifier object for the given device. The
    QSocketNotifier class provides support for monitoring activity on
    a file descriptor. When the socket notifier receives data, it will
    call the mouse driver's mouseChanged() function to send the event
    to the \l{Qt for Embedded Linux} server application for relaying to
    clients.

    If you are creating a driver for a device that needs calibration
    or noise reduction, such as a touchscreen, use the
    QWSCalibratedMouseHandler subclass instead to take advantage of
    the calibrate() and clearCalibration() functions. The \l
    {qws/mousecalibration}{Mouse Calibration}
    demonstrates how to write a simple program using the mechanisms
    provided by the QWSMouseHandler class to calibrate a mouse driver.

    Note that when deriving from the QWSMouseHandler class, the
    resume() and suspend() functions must be reimplemented to control
    the flow of mouse input, i.e., the default implementation does
    nothing. Reimplementations of these functions typically call the
    QSocketNotifier::setEnabled() function to enable or disable the
    socket notifier, respectively.

    In addition, QWSMouseHandler provides the setScreen() function
    that allows you to specify a screen for your mouse driver and the
    limitToScreen() function that ensures that a given position is
    within this screen's boundaries (changing the position if
    necessary). Finally, QWSMouseHandler provides the pos() function
    returning the current mouse position.

    \sa QMouseDriverPlugin, QMouseDriverFactory, {Qt for Embedded Linux Pointer
    Handling}
*/


/*!
    \fn void QWSMouseHandler::suspend()

    Implement this function to suspend reading and handling of mouse
    events, e.g., call the QSocketNotifier::setEnabled() function to
    disable the socket notifier.

    \sa resume()
*/

/*!
    \fn void QWSMouseHandler::resume()

    Implement this function to resume reading and handling mouse
    events, e.g., call the QSocketNotifier::setEnabled() function to
    enable the socket notifier.

    \sa suspend()
*/

/*!
    \fn const QPoint &QWSMouseHandler::pos() const

    Returns the current mouse position.

    \sa mouseChanged(), limitToScreen()
*/

/*!
    Constructs a mouse driver. The \a driver and \a device arguments
    are passed by the QWS_MOUSE_PROTO environment variable.

    Call the QWSServer::setMouseHandler() function to make the newly
    created mouse driver, the primary driver. Note that the primary
    driver is controlled by the system, i.e., the system will delete
    it upon exit.
*/
QWSMouseHandler::QWSMouseHandler(const QString &, const QString &)
    : mousePos(QWSServer::mousePosition), d_ptr(new QWSMouseHandlerPrivate)
{
}

/*!
    Destroys this mouse driver.

    Do not call this function if this driver is the primary mouse
    driver, i.e., if QWSServer::setMouseHandler() function has been
    called passing this driver as argument. The primary mouse
    driver is deleted by the system.
*/
QWSMouseHandler::~QWSMouseHandler()
{
    delete d_ptr;
}

/*!
    Ensures that the given \a position is within the screen's
    boundaries, changing the \a position if necessary.

    \sa pos(), setScreen()
*/

void QWSMouseHandler::limitToScreen(QPoint &position)
{
    position.setX(qMin(d_ptr->screen->deviceWidth() - 1, qMax(0, position.x())));
    position.setY(qMin(d_ptr->screen->deviceHeight() - 1, qMax(0, position.y())));
}

/*!
    \since 4.2

    Sets the screen for this mouse driver to be the given \a screen.

    \sa limitToScreen()
*/
void QWSMouseHandler::setScreen(const QScreen *screen)
{
    d_ptr->screen = (screen ? screen : qt_screen);
}

/*!
    Notifies the system of a new mouse event.

    This function updates the current mouse position and sends the
    event to the \l{Qt for Embedded Linux} server application for
    delivery to the correct widget. Note that a custom mouse driver must call
    this function whenever it wants to deliver a new mouse event.

    The given \a position is the global position of the mouse cursor.
    The \a state parameter is a bitmask of the Qt::MouseButton enum's
    values, indicating which mouse buttons are pressed. The \a wheel
    parameter is the delta value of the mouse wheel as returned by
    QWheelEvent::delta().

    \sa pos()
*/
void QWSMouseHandler::mouseChanged(const QPoint &position, int state, int wheel)
{
    mousePos = position + d_ptr->screen->offset();
    QWSServer::sendMouseEvent(mousePos, state, wheel);
}

/*!
    \fn QWSMouseHandler::clearCalibration()

    This virtual function allows subclasses of QWSMouseHandler to
    clear the calibration information. Note that the default
    implementation does nothing.

    \sa QWSCalibratedMouseHandler::clearCalibration(), calibrate()
*/

/*!
    \fn QWSMouseHandler::calibrate(const QWSPointerCalibrationData *data)

    This virtual function allows subclasses of QWSMouseHandler to set
    the calibration information passed in the given \a data. Note that
    the default implementation does nothing.

    \sa QWSCalibratedMouseHandler::calibrate(), clearCalibration()
*/

/*! \fn QWSMouseHandler::getCalibration(QWSPointerCalibrationData *data) const
    This virtual function allows subclasses of QWSMouseHandler
    to fill in the device coordinates in \a data with values
    that correspond to screen coordinates that are already in
    \a data. Note that the default implementation does nothing.
 */

/*!
    \class QWSCalibratedMouseHandler
    \ingroup qws

    \brief The QWSCalibratedMouseHandler class provides mouse
    calibration and noise reduction in Qt for Embedded Linux.

    Note that this class is only available in \l{Qt for Embedded Linux}.

    \l{Qt for Embedded Linux} provides ready-made drivers for several mouse
    protocols, see the \l{Qt for Embedded Linux Pointer Handling}{pointer
    handling} documentation for details. In general, custom mouse
    drivers can be implemented by subclassing the QWSMouseHandler
    class. But when the system device does not have a fixed mapping
    between device and screen coordinates and/or produces noisy events
    (e.g., a touchscreen), you should derive from the
    QWSCalibratedMouseHandler class instead to take advantage of its
    calibration functionality. As always, you must also create a mouse
    driver plugin (derived from QMouseDriverPlugin);
    the implementation of the QMouseDriverFactory class will then
    automatically detect the plugin, and load the driver into the
    server application at run-time using Qt's
    \l{How to Create Qt Plugins}{plugin system}.

    QWSCalibratedMouseHandler provides an implementation of the
    calibrate() function to update the calibration parameters based on