source: trunk/src/gui/text/qabstractfontengine_qws.cpp@ 632

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#include "qabstractfontengine_qws.h"
#include "qabstractfontengine_p.h"

#include <private/qtextengine_p.h>
#include <private/qpaintengine_raster_p.h>

#include <qmath.h>

QT_BEGIN_NAMESPACE

class QFontEngineInfoPrivate
{
public:
    inline QFontEngineInfoPrivate()
        : pixelSize(0), weight(QFont::Normal), style(QFont::StyleNormal)
    {}

    QString family;
    qreal pixelSize;
    int weight;
    QFont::Style style;
    QList<QFontDatabase::WritingSystem> writingSystems;
};

/*!
    \class QFontEngineInfo
    \preliminary
    \brief The QFontEngineInfo class describes a specific font provided by a font engine plugin.
    \since 4.3
    \ingroup qws

    \tableofcontents

    QFontEngineInfo is used to describe a request of a font to a font engine plugin as well as to
    describe the actual fonts a plugin provides.

    \sa QAbstractFontEngine, QFontEnginePlugin
*/

/*!
   Constructs a new empty QFontEngineInfo.
*/
QFontEngineInfo::QFontEngineInfo()
{
    d = new QFontEngineInfoPrivate;
}

/*!
   Constructs a new QFontEngineInfo with the specified \a family.
   The resulting object represents a freely scalable font with normal
   weight and style.
*/
QFontEngineInfo::QFontEngineInfo(const QString &family)
{
    d = new QFontEngineInfoPrivate;
    d->family = family;
}

/*!
   Creates a new font engine info object with the same attributes as \a other.
*/
QFontEngineInfo::QFontEngineInfo(const QFontEngineInfo &other)
    : d(new QFontEngineInfoPrivate(*other.d))
{
}

/*!
   Assigns \a other to this font engine info object, and returns a reference
   to this.
*/
QFontEngineInfo &QFontEngineInfo::operator=(const QFontEngineInfo &other)
{
    *d = *other.d;
    return *this;
}

/*!
   Destroys this QFontEngineInfo object.
*/
QFontEngineInfo::~QFontEngineInfo()
{
    delete d;
}

/*!
   \property QFontEngineInfo::family
   the family name of the font
*/

void QFontEngineInfo::setFamily(const QString &family)
{
    d->family = family;
}

QString QFontEngineInfo::family() const
{
    return d->family;
}

/*!
   \property QFontEngineInfo::pixelSize
   the pixel size of the font

   A pixel size of 0 represents a freely scalable font.
*/

void QFontEngineInfo::setPixelSize(qreal size)
{
    d->pixelSize = size;
}

qreal QFontEngineInfo::pixelSize() const
{
    return d->pixelSize;
}

/*!
   \property QFontEngineInfo::weight
   the weight of the font

   The value should be from the \l{QFont::Weight} enumeration.
*/

void QFontEngineInfo::setWeight(int weight)
{
    d->weight = weight;
}

int QFontEngineInfo::weight() const
{
    return d->weight;
}

/*!
   \property QFontEngineInfo::style
   the style of the font
*/

void QFontEngineInfo::setStyle(QFont::Style style)
{
    d->style = style;
}

QFont::Style QFontEngineInfo::style() const
{
    return d->style;
}

/*!
   \property QFontEngineInfo::writingSystems
   the writing systems supported by the font

   An empty list means that any writing system is supported.
*/

QList<QFontDatabase::WritingSystem> QFontEngineInfo::writingSystems() const
{
    return d->writingSystems;
}

void QFontEngineInfo::setWritingSystems(const QList<QFontDatabase::WritingSystem> &writingSystems)
{
    d->writingSystems = writingSystems;
}

class QFontEnginePluginPrivate : public QObjectPrivate
{
    Q_DECLARE_PUBLIC(QFontEnginePlugin)

    QString foundry;
};

/*!
    \class QFontEnginePlugin
    \preliminary
    \brief The QFontEnginePlugin class is the base class for font engine factory plugins in Qt for Embedded Linux.
    \since 4.3
    \ingroup qws
    \ingroup plugins

    \tableofcontents

    QFontEnginePlugin is provided by font engine plugins to create
    instances of subclasses of QAbstractFontEngine.

    The member functions create() and availableFontEngines() must be
    implemented.

    \sa QAbstractFontEngine, QFontEngineInfo
*/

/*!
  Creates a font engine plugin that creates font engines with the
  specified \a foundry and \a parent.
*/
QFontEnginePlugin::QFontEnginePlugin(const QString &foundry, QObject *parent)
    : QObject(*new QFontEnginePluginPrivate, parent)
{
    Q_D(QFontEnginePlugin);
    d->foundry = foundry;
}

/*!
   Destroys this font engine plugin.
*/
QFontEnginePlugin::~QFontEnginePlugin()
{
}

/*!
   Returns a list of foundries the font engine plugin provides.
   The default implementation returns the foundry specified with the constructor.
*/
QStringList QFontEnginePlugin::keys() const
{
    Q_D(const QFontEnginePlugin);
    return QStringList(d->foundry);
}

/*!
    \fn QAbstractFontEngine *QFontEnginePlugin::create(const QFontEngineInfo &info)

    Implemented in subclasses to create a new font engine that provides a font that
    matches \a info.
*/

/*!
    \fn QList<QFontEngineInfo> QFontEnginePlugin::availableFontEngines() const

    Implemented in subclasses to return a list of QFontEngineInfo objects that represents all font
    engines the plugin can create.
*/

class QAbstractFontEnginePrivate : public QObjectPrivate
{
    Q_DECLARE_PUBLIC(QAbstractFontEngine)
public:
};

//The <classname> class is|provides|contains|specifies...
/*!
    \class QAbstractFontEngine
    \preliminary
    \brief The QAbstractFontEngine class is the base class for font engine plugins in Qt for Embedded Linux.
    \since 4.3
    \ingroup qws

    \tableofcontents

    QAbstractFontEngine is implemented by font engine plugins through QFontEnginePlugin.

    \sa QFontEnginePlugin, QFontEngineInfo
*/

/*!
   \enum QAbstractFontEngine::Capability

   This enum describes the capabilities of a font engine.

   \value CanRenderGlyphs_Gray The font engine can render individual glyphs into 8 bpp images.
   \value CanRenderGlyphs_Mono The font engine can render individual glyphs into 1 bpp images.
   \value CanRenderGlyphs The font engine can render individual glyphs into images.
   \value CanOutlineGlyphs The font engine can convert glyphs to painter paths.
*/

/*!
   \enum QAbstractFontEngine::FontProperty

   This enum describes the properties of a font provided by a font engine.

   \value Ascent The ascent of the font, specified as a 26.6 fixed point value.
   \value Descent The descent of the font, specified as a 26.6 fixed point value.
   \value Leading The leading of the font, specified as a 26.6 fixed point value.
   \value XHeight The 'x' height of the font, specified as a 26.6 fixed point value.
   \value AverageCharWidth The average character width of the font, specified as a 26.6 fixed point value.
   \value LineThickness The thickness of the underline and strikeout lines for the font, specified as a 26.6 fixed point value.
   \value UnderlinePosition The distance from the base line to the underline position for the font, specified as a 26.6 fixed point value.
   \value MaxCharWidth The width of the widest character in the font, specified as a 26.6 fixed point value.
   \value MinLeftBearing The minimum left bearing of the font, specified as a 26.6 fixed point value.
   \value MinRightBearing The maximum right bearing of the font, specified as a 26.6 fixed point value.
   \value GlyphCount The number of glyphs in the font, specified as an integer value.
   \value CacheGlyphsHint A boolean value specifying whether rendered glyphs should be cached by Qt.
   \value OutlineGlyphsHint A boolean value specifying whether the font engine prefers outline drawing over image rendering for uncached glyphs.
*/

/*!
   \enum QAbstractFontEngine::TextShapingFlag

   This enum describes flags controlling conversion of characters to glyphs and their metrics.

   \value RightToLeft The text is used in a right-to-left context.
   \value ReturnDesignMetrics Return font design metrics instead of pixel metrics.
*/

/*!
   \typedef QAbstractFontEngine::Fixed

   This type is \c int, interpreted as a 26.6 fixed point value.
*/

/*!
   \class QAbstractFontEngine::GlyphMetrics
   \brief QAbstractFontEngine::GlyphMetrics defines the metrics of a single glyph.
   \preliminary
   \since 4.3
*/

/*!
   \variable QAbstractFontEngine::GlyphMetrics::x

   The horizontal offset from the origin.
*/

/*!
   \fn QAbstractFontEngine::GlyphMetrics::GlyphMetrics()

   Constructs an empty glyph metrics object with all values
   set to zero.
*/

/*!
   \variable QAbstractFontEngine::GlyphMetrics::y

   The vertical offset from the origin (baseline).
*/

/*!
   \variable QAbstractFontEngine::GlyphMetrics::width

   The width of the glyph.
*/

/*!
   \variable QAbstractFontEngine::GlyphMetrics::height

   The height of the glyph.
*/

/*!
   \variable QAbstractFontEngine::GlyphMetrics::advance

   The advance of the glyph.
*/

/*!
   \class QAbstractFontEngine::FixedPoint
   \brief QAbstractFontEngine::FixedPoint defines a point in the place using 26.6 fixed point precision.
   \preliminary
   \since 4.3
*/

/*!
   \variable QAbstractFontEngine::FixedPoint::x

   The x coordinate of this point.
*/

/*!
   \variable QAbstractFontEngine::FixedPoint::y

   The y coordinate of this point.
*/

/*!
   Constructs a new QAbstractFontEngine with the given \a parent.
*/
QAbstractFontEngine::QAbstractFontEngine(QObject *parent)
    : QObject(*new QAbstractFontEnginePrivate, parent)
{
}

/*!
   Destroys this QAbstractFontEngine object.
*/
QAbstractFontEngine::~QAbstractFontEngine()
{
}

/*!