path: root/src/gui/text/qplatformfontdatabase_qpa.cpp

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#include "qplatformfontdatabase_qpa.h"
#include <QtGui/private/qfontengine_p.h>
#include <QtGui/private/qfontengine_qpa_p.h>
#include <QtCore/QLibraryInfo>
#include <QtCore/QDir>

QT_BEGIN_NAMESPACE

extern void qt_registerFont(const QString &familyname, const QString &foundryname, int weight,
                                         QFont::Style style, int stretch, bool antialiased,bool scalable, int pixelSize,
                                         const QSupportedWritingSystems &writingSystems, void *hanlde);

/*!
    \fn void QPlatformFontDatabase::registerQPF2Font(const QByteArray &dataArray, void *)

    Registers the pre-rendered QPF2 font contained in the given \a dataArray.

    \sa registerFont()
*/
void QPlatformFontDatabase::registerQPF2Font(const QByteArray &dataArray, void *handle)
{
    if (dataArray.size() == 0)
        return;

    const uchar *data = reinterpret_cast<const uchar *>(dataArray.constData());
    if (QFontEngineQPA::verifyHeader(data, dataArray.size())) {
        QString fontName = QFontEngineQPA::extractHeaderField(data, QFontEngineQPA::Tag_FontName).toString();
        int pixelSize = QFontEngineQPA::extractHeaderField(data, QFontEngineQPA::Tag_PixelSize).toInt();
        QVariant weight = QFontEngineQPA::extractHeaderField(data, QFontEngineQPA::Tag_Weight);
        QVariant style = QFontEngineQPA::extractHeaderField(data, QFontEngineQPA::Tag_Style);
        QByteArray writingSystemBits = QFontEngineQPA::extractHeaderField(data, QFontEngineQPA::Tag_WritingSystems).toByteArray();

        if (!fontName.isEmpty() && pixelSize) {
            QFont::Weight fontWeight = QFont::Normal;
            if (weight.type() == QVariant::Int || weight.type() == QVariant::UInt)
                fontWeight = QFont::Weight(weight.toInt());

            QFont::Style fontStyle = static_cast<QFont::Style>(style.toInt());

            QSupportedWritingSystems writingSystems;
            for (int i = 0; i < writingSystemBits.count(); ++i) {
                uchar currentByte = writingSystemBits.at(i);
                for (int j = 0; j < 8; ++j) {
                    if (currentByte & 1)
                        writingSystems.setSupported(QFontDatabase::WritingSystem(i * 8 + j));
                    currentByte >>= 1;
                }
            }
            QFont::Stretch stretch = QFont::Unstretched;
            registerFont(fontName,QString(),fontWeight,fontStyle,stretch,true,false,pixelSize,writingSystems,handle);
        }
    } else {
        qDebug() << "header verification of QPF2 font failed. maybe it is corrupt?";
    }
}

/*!
    \fn void QPlatformFontDatabase::registerFont(const QString &familyName,
        const QString &foundryName, QFont::Weight weight, QFont::Style style,
        QFont::Stretch stretch, bool antialiased, bool scalable, int pixelSize,
        const QSupportedWritingSystems &writingSystems, void *usrPtr)

    Registers a font with the given set of attributes describing the font's
    foundry, family name, style and stretch information, pixel size, and
    supported writing systems. Additional information about whether the font
    can be scaled and antialiased can also be provided.

    The foundry name and font family are described by \a foundryName and
    \a familyName. The font weight (light, normal, bold, etc.), style (normal,
    oblique, italic) and stretch information (condensed, expanded, unstretched,
    etc.) are specified by \a weight, \a style and \a stretch.

    Some fonts can be antialiased and scaled; \a scalable and \a antialiased
    can be set to true for fonts with these attributes. The intended pixel
    size of non-scalable fonts is specified by \a pixelSize; this value will be
    ignored for scalable fonts.

    The writing systems supported by the font are specified by the
    \a writingSystems argument.

    \sa registerQPF2Font()
*/
void QPlatformFontDatabase::registerFont(const QString &familyname, const QString &foundryname, QFont::Weight weight,
                                         QFont::Style style, QFont::Stretch stretch, bool antialiased, bool scalable, int pixelSize,
                                         const QSupportedWritingSystems &writingSystems, void *usrPtr)
{
    if (scalable)
        pixelSize = 0;
    qt_registerFont(familyname,foundryname,weight,style,stretch,antialiased,scalable,pixelSize,writingSystems,usrPtr);
}

class QWritingSystemsPrivate
{
public:
    QWritingSystemsPrivate()
        : ref(1)
        , vector(QFontDatabase::WritingSystemsCount,false)
    {
    }

    QWritingSystemsPrivate(const QWritingSystemsPrivate *other)
        : ref(1)
        , vector(other->vector)
    {
    }

    QAtomicInt ref;
    QVector<bool> vector;
};

QSupportedWritingSystems::QSupportedWritingSystems()
{
    d = new QWritingSystemsPrivate;
}

QSupportedWritingSystems::QSupportedWritingSystems(const QSupportedWritingSystems &other)
{
    d = other.d;
    d->ref.ref();
}

/*!
    Assigns the \a other supported writing systems object to this object.
*/
QSupportedWritingSystems &QSupportedWritingSystems::operator=(const QSupportedWritingSystems &other)
{
    if (d != other.d) {
        other.d->ref.ref();
        if (!d->ref.deref())
            delete d;
        d = other.d;
    }
    return *this;
}

/*!
    Destroys the object.
*/
QSupportedWritingSystems::~QSupportedWritingSystems()
{
    if (!d->ref.deref())
        delete d;
}

void QSupportedWritingSystems::detach()
{
    if (d->ref != 1) {
        QWritingSystemsPrivate *newd = new QWritingSystemsPrivate(d);
        if (!d->ref.deref())
            delete d;
        d = newd;
    }
}

/*!
    Sets the supported state of the writing system given by \a writingSystem to
    the value specified by \a support. A value of true indicates that the
    writing system is supported; a value of false indicates that it is
    unsupported.

    \sa supported()
*/
void QSupportedWritingSystems::setSupported(QFontDatabase::WritingSystem writingSystem, bool support)
{
    detach();
    d->vector[writingSystem] = support;
}

/*!
    Returns true if the writing system given by \a writingSystem is supported;
    otherwise returns false.

    \sa setSupported()
*/
bool QSupportedWritingSystems::supported(QFontDatabase::WritingSystem writingSystem) const
{
    return d->vector.at(writingSystem);
}

/*!
    \class QSupportedWritingSystems
    \brief The QSupportedWritingSystems class is used when registering fonts with the internal Qt
    fontdatabase
    \ingroup painting
    \since 4.8

    Its to provide an easy to use interface for indicating what writing systems a specific font
    supports.

*/

/*!
  This function is called once at startup by Qts internal fontdatabase. Reimplement this function
  in a subclass for a convenient place to initialise the internal fontdatabase.

  The default implementation looks in the fontDir() location and registers all qpf2 fonts.
*/
void QPlatformFontDatabase::populateFontDatabase()
{
    QString fontpath = fontDir();

    if(!QFile::exists(fontpath)) {
        qFatal("QFontDatabase: Cannot find font directory %s - is Qt installed correctly?",
               qPrintable(fontpath));
    }

    QDir dir(fontpath);
    dir.setNameFilters(QStringList() << QLatin1String("*.qpf2"));
    dir.refresh();
    for (int i = 0; i < int(dir.count()); ++i) {
        const QByteArray fileName = QFile::encodeName(dir.absoluteFilePath(dir[i]));
        QFile file(QString::fromLocal8Bit(fileName));
        if (file.open(QFile::ReadOnly)) {
            const QByteArray fileData = file.readAll();
            QByteArray *fileDataPtr = new QByteArray(fileData);
            registerQPF2Font(fileData, fileDataPtr);
        }
    }
}

/*!
    Returns the font engine that can be used to render the font described by
    the font definition, \a fontDef, in the specified \a script.
*/
QFontEngine *QPlatformFontDatabase::fontEngine(const QFontDef &fontDef, QUnicodeTables::Script script, void *handle)
{
    Q_UNUSED(script);
    Q_UNUSED(handle);
    QByteArray *fileDataPtr = static_cast<QByteArray *>(handle);
    QFontEngineQPA *engine = new QFontEngineQPA(fontDef,*fileDataPtr);
    //qDebug() << fontDef.pixelSize << fontDef.weight << fontDef.style << fontDef.stretch << fontDef.styleHint << fontDef.styleStrategy << fontDef.family << script;
    return engine;
}

QFontEngine *QPlatformFontDatabase::fontEngine(const QByteArray &fontData, qreal pixelSize,
                                               QFont::HintingPreference hintingPreference)
{
    Q_UNUSED(fontData);
    Q_UNUSED(pixelSize);
    Q_UNUSED(hintingPreference);
    qWarning("This plugin does not support font engines created directly from font data");
    return 0;
}

/*!
    Returns a list of alternative fonts for the specified \a family and
    \a style and \a script using the \a styleHint given.
*/
QStringList QPlatformFontDatabase::fallbacksForFamily(const QString family, const QFont::Style &style, const QFont::StyleHint &styleHint, const QUnicodeTables::Script &script) const
{
    Q_UNUSED(family);
    Q_UNUSED(style);
    Q_UNUSED(styleHint);
    Q_UNUSED(script);
    return QStringList();
}

/*!
    Adds an application font described by the font contained supplied \a fontData
    or using the font contained in the file referenced by \a fileName. Returns
    a list of family names, or an empty list if the font could not be added.

    \note The default implementation of this function does not add an application
    font. Subclasses should reimplement this function to perform the necessary
    loading and registration of fonts.
*/
QStringList QPlatformFontDatabase::addApplicationFont(const QByteArray &fontData, const QString &fileName)
{
    Q_UNUSED(fontData);
    Q_UNUSED(fileName);

    qWarning("This plugin does not support application fonts");
    return QStringList();
}

/*!
    Releases the font handle and deletes any associated data loaded from a file.
*/
void QPlatformFontDatabase::releaseHandle(void *handle)
{
    QByteArray *fileDataPtr = static_cast<QByteArray *>(handle);
    delete fileDataPtr;
}

/*!
    Returns the path to the font directory.

    The font directory is stored in the general Qt settings unless it has been
    overridden by the \c QT_QPA_FONTDIR environment variable.

    When using builds of Qt that do not support settings, the \c QT_QPA_FONTDIR
    environment variable is the only way to specify the font directory.
*/
QString QPlatformFontDatabase::fontDir() const
{
    QString fontpath = QString::fromLocal8Bit(qgetenv("QT_QPA_FONTDIR"));
    if (fontpath.isEmpty()) {
#ifndef QT_NO_SETTINGS
        fontpath = QLibraryInfo::location(QLibraryInfo::LibrariesPath);
        fontpath += QLatin1String("/fonts");
#endif
    }

    return fontpath;
}

/*!
    \class QPlatformFontDatabase
    \brief The QPlatformFontDatabase class makes it possible to customize how fonts
    are discovered and how they are rendered
    \since 4.8

    \ingroup painting

    QPlatformFontDatabase is the superclass which is intended to let platform implementations use
    native font handling.

    Qt has its internal font database which it uses to discover available fonts on the
    user's system. To be able to populate this database subclass this class, and
    reimplement populateFontDatabase().

    Use the function registerFont() to populate the internal font database.

    Sometimes a specified font does not have the required glyphs; in such a case, the
    fallbackForFamily() function is called automatically to find alternative font
    families that can supply alternatives to the missing glyphs.

    \sa QSupportedWritingSystems
*/
QT_END_NAMESPACE