gui/embedded/qmousetslib_qws.cpp

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#include "qmousetslib_qws.h"

#if !defined(QT_NO_QWS_MOUSE_TSLIB) || defined(QT_PLUGIN)

#include <QtCore/qregexp.h>
#include <QtCore/qstringlist.h>
#include "qsocketnotifier.h"
#include "qscreen_qws.h"

#include <tslib.h>
#include <errno.h>

QT_BEGIN_NAMESPACE

#ifdef TSLIBMOUSEHANDLER_DEBUG
#  include <QtCore/QDebug>
#endif

/*!
    \internal

    \class QWSTslibMouseHandler
    \ingroup qws

    \brief The QWSTslibMouseHandler class implements a mouse driver
    for the Universal Touch Screen Library, tslib.

    QWSTslibMouseHandler inherits the QWSCalibratedMouseHandler class,
    providing calibration and noise reduction functionality in
    addition to generating mouse events, for devices using the
    Universal Touch Screen Library.

    To be able to compile this mouse handler, \l{Qt for Embedded Linux}
    must be configured with the \c -qt-mouse-tslib option, see the
    \l{Pointer Handling} documentation for details. In addition, the tslib
    headers and library must be present in the build environment.  The
    tslib sources can be downloaded from \l
    {http://tslib.berlios.de/}.  Use the \c -L and \c -I options
    with \c configure to explicitly specify the location of the
    library and its headers:

    \snippet doc/src/snippets/code/src_gui_embedded_qmousetslib_qws.cpp 0

    In order to use this mouse handler, tslib must also be correctly
    installed on the target machine. This includes providing a \c
    ts.conf configuration file and setting the necessary environment
    variables, see the README file provided with tslib for details.

    The ts.conf file will usually contain the following two lines

    \snippet doc/src/snippets/code/src_gui_embedded_qmousetslib_qws.cpp 1

    To make \l{Qt for Embedded Linux} explicitly choose the tslib mouse
    handler, set the QWS_MOUSE_PROTO environment variable.

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

class QWSTslibMouseHandlerPrivate : public QObject
{
    Q_OBJECT
public:
    QWSTslibMouseHandlerPrivate(QWSTslibMouseHandler *h,
                                const QString &device);
    ~QWSTslibMouseHandlerPrivate();

    void suspend();
    void resume();

    void calibrate(const QWSPointerCalibrationData *data);
    void clearCalibration();

private:
    QWSTslibMouseHandler *handler;
    struct tsdev *dev;
    QSocketNotifier *mouseNotifier;
    int jitter_limit;

    struct ts_sample lastSample;
    bool wasPressed;
    int lastdx;
    int lastdy;

    bool calibrated;
    QString devName;

    bool open();
    void close();
    inline bool get_sample(struct ts_sample *sample);

private slots:
    void readMouseData();
};

QWSTslibMouseHandlerPrivate::QWSTslibMouseHandlerPrivate(QWSTslibMouseHandler *h,
                                                         const QString &device)
    : handler(h), dev(0), mouseNotifier(0), jitter_limit(3)
{
    QStringList args = device.split(QLatin1Char(':'), QString::SkipEmptyParts);
    QRegExp jitterRegex(QLatin1String("^jitter_limit=(\\d+)$"));
    int index = args.indexOf(jitterRegex);
    if (index >= 0) {
        jitter_limit = jitterRegex.cap(1).toInt();
        args.removeAt(index);
    }

    devName = args.join(QString());

    if (devName.isNull()) {
        const char *str = getenv("TSLIB_TSDEVICE");
        if (str)
            devName = QString::fromLocal8Bit(str);
    }

    if (devName.isNull())
        devName = QLatin1String("/dev/ts");

    if (!open())
        return;

    calibrated = true;

    int fd = ts_fd(dev);
    mouseNotifier = new QSocketNotifier(fd, QSocketNotifier::Read, this);
    connect(mouseNotifier, SIGNAL(activated(int)),this, SLOT(readMouseData()));
    resume();
}

QWSTslibMouseHandlerPrivate::~QWSTslibMouseHandlerPrivate()
{
    close();
}

bool QWSTslibMouseHandlerPrivate::open()
{
    dev = ts_open(devName.toLocal8Bit().constData(), 1);
    if (!dev) {
        qCritical("QWSTslibMouseHandlerPrivate: ts_open() failed"
                  " with error: '%s'", strerror(errno));
        qCritical("Please check your tslib installation!");
        return false;
    }

    if (ts_config(dev)) {
        qCritical("QWSTslibMouseHandlerPrivate: ts_config() failed"
                  " with error: '%s'", strerror(errno));
        qCritical("Please check your tslib installation!");
        close();
        return false;
    }

    return true;
}

void QWSTslibMouseHandlerPrivate::close()
{
    if (dev)
        ts_close(dev);
}

void QWSTslibMouseHandlerPrivate::suspend()
{
    if (mouseNotifier)
        mouseNotifier->setEnabled(false);
}

void QWSTslibMouseHandlerPrivate::resume()
{
    memset(&lastSample, 0, sizeof(lastSample));
    wasPressed = false;
    lastdx = 0;
    lastdy = 0;
    if (mouseNotifier)
        mouseNotifier->setEnabled(true);
}

bool QWSTslibMouseHandlerPrivate::get_sample(struct ts_sample *sample)
{
    if (!calibrated)
        return (ts_read_raw(dev, sample, 1) == 1);

    return (ts_read(dev, sample, 1) == 1);
}

void QWSTslibMouseHandlerPrivate::readMouseData()
{
    if (!qt_screen)
        return;

    for(;;) {
        struct ts_sample sample = lastSample;
        bool pressed = wasPressed;

        // Fast return if there's no events.
        if (!get_sample(&sample))
            return;
        pressed = (sample.pressure > 0);

        // Only return last sample unless there's a press/release event.
        while (pressed == wasPressed) {
            if (!get_sample(&sample))
                break;
            pressed = (sample.pressure > 0);
        }

        // work around missing coordinates on mouse release
        if (!pressed && sample.x == 0 && sample.y == 0) {
            sample.x = lastSample.x;
            sample.y = lastSample.y;
        }

        int dx = sample.x - lastSample.x;
        int dy = sample.y - lastSample.y;

        // Remove small movements in oppsite direction
        if (dx * lastdx < 0 && qAbs(dx) < jitter_limit) {
            sample.x = lastSample.x;
            dx = 0;
        }
        if (dy * lastdy < 0 && qAbs(dy) < jitter_limit) {
            sample.y = lastSample.y;
            dy = 0;
        }

        if (wasPressed == pressed && dx == 0 && dy == 0)
            return;

#ifdef TSLIBMOUSEHANDLER_DEBUG
        qDebug() << "last" << QPoint(lastSample.x, lastSample.y)
                 << "curr" << QPoint(sample.x, sample.y)
                 << "dx,dy" << QPoint(dx, dy)
                 << "ddx,ddy" << QPoint(dx*lastdx, dy*lastdy)
                 << "pressed" << wasPressed << pressed;
#endif

        lastSample = sample;
        wasPressed = pressed;
        if (dx != 0)
            lastdx = dx;
        if (dy != 0)
            lastdy = dy;

        const QPoint p(sample.x, sample.y);
        if (calibrated) {
            // tslib should do all the translation and filtering, so we send a
            // "raw" mouse event
            handler->QWSMouseHandler::mouseChanged(p, pressed);
        } else {
            handler->sendFiltered(p, pressed);
        }
    }
}

void QWSTslibMouseHandlerPrivate::clearCalibration()
{
    suspend();
    close();
    handler->QWSCalibratedMouseHandler::clearCalibration();
    calibrated = false;
    open();
    resume();
}

void QWSTslibMouseHandlerPrivate::calibrate(const QWSPointerCalibrationData *data)
{
    suspend();
    close();
    // default implementation writes to /etc/pointercal
    // using the same format as the tslib linear module.
    handler->QWSCalibratedMouseHandler::calibrate(data);
    calibrated = true;
    open();
    resume();
}

/*!
    \internal
*/
QWSTslibMouseHandler::QWSTslibMouseHandler(const QString &driver,
                                           const QString &device)
    : QWSCalibratedMouseHandler(driver, device)
{
    d = new QWSTslibMouseHandlerPrivate(this, device);
}

/*!
    \internal
*/
QWSTslibMouseHandler::~QWSTslibMouseHandler()
{
    delete d;
}

/*!
    \reimp
*/
void QWSTslibMouseHandler::suspend()
{
    d->suspend();
}

/*!
    \reimp
*/
void QWSTslibMouseHandler::resume()
{
    d->resume();
}

/*!
    \reimp
*/
void QWSTslibMouseHandler::clearCalibration()
{
    d->clearCalibration();
}

/*!
    \reimp
*/
void QWSTslibMouseHandler::calibrate(const QWSPointerCalibrationData *data)
{
    d->calibrate(data);
}

QT_END_NAMESPACE

#include "qmousetslib_qws.moc"

#endif //QT_NO_QWS_MOUSE_TSLIB