qrawfont.cpp

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#include "qglobal.h"

#if !defined(QT_NO_RAWFONT)

#include "qrawfont.h"
#include "qrawfont_p.h"

#include <QtCore/qendian.h>

QT_BEGIN_NAMESPACE

QRawFont::QRawFont()
    : d(new QRawFontPrivate)
{
}

QRawFont::QRawFont(const QString &fileName,
                   qreal pixelSize,
                   QFont::HintingPreference hintingPreference)
    : d(new QRawFontPrivate)
{
    loadFromFile(fileName, pixelSize, hintingPreference);
}

QRawFont::QRawFont(const QByteArray &fontData,
                   qreal pixelSize,
                   QFont::HintingPreference hintingPreference)
    : d(new QRawFontPrivate)
{
    loadFromData(fontData, pixelSize, hintingPreference);
}

QRawFont::QRawFont(const QRawFont &other)
{
    d = other.d;
}

QRawFont::~QRawFont()
{
}

QRawFont &QRawFont::operator=(const QRawFont &other)
{
    d = other.d;
    return *this;
}

bool QRawFont::isValid() const
{
    return d->isValid();
}

void QRawFont::loadFromFile(const QString &fileName,
                            qreal pixelSize,
                            QFont::HintingPreference hintingPreference)
{
    QFile file(fileName);
    if (file.open(QIODevice::ReadOnly))
        loadFromData(file.readAll(), pixelSize, hintingPreference);
}

void QRawFont::loadFromData(const QByteArray &fontData,
                            qreal pixelSize,
                            QFont::HintingPreference hintingPreference)
{
    d.detach();
    d->cleanUp();
    d->hintingPreference = hintingPreference;
    d->thread = QThread::currentThread();
    d->platformLoadFromData(fontData, pixelSize, hintingPreference);
}

QImage QRawFont::alphaMapForGlyph(quint32 glyphIndex, AntialiasingType antialiasingType,
                                  const QTransform &transform) const
{
    if (!d->isValid())
        return QImage();

    if (antialiasingType == SubPixelAntialiasing)
        return d->fontEngine->alphaRGBMapForGlyph(glyphIndex, QFixed(), 0, transform);

    return d->fontEngine->alphaMapForGlyph(glyphIndex, QFixed(), transform);
}

QPainterPath QRawFont::pathForGlyph(quint32 glyphIndex) const
{
    if (!d->isValid())
        return QPainterPath();

    QFixedPoint position;
    QPainterPath path;
    d->fontEngine->addGlyphsToPath(&glyphIndex, &position, 1, &path, 0);
    return path;
}

bool QRawFont::operator==(const QRawFont &other) const
{
    return d->fontEngine == other.d->fontEngine;
}

qreal QRawFont::ascent() const
{
    return d->isValid() ? d->fontEngine->ascent().toReal() : 0.0;
}

qreal QRawFont::descent() const
{
    return d->isValid() ? d->fontEngine->descent().toReal() : 0.0;
}

qreal QRawFont::xHeight() const
{
    return d->isValid() ? d->fontEngine->xHeight().toReal() : 0.0;
}

qreal QRawFont::leading() const
{
    return d->isValid() ? d->fontEngine->leading().toReal() : 0.0;
}

qreal QRawFont::averageCharWidth() const
{
    return d->isValid() ? d->fontEngine->averageCharWidth().toReal() : 0.0;
}

qreal QRawFont::maxCharWidth() const
{
    return d->isValid() ? d->fontEngine->maxCharWidth() : 0.0;
}

qreal QRawFont::pixelSize() const
{
    return d->isValid() ? d->fontEngine->fontDef.pixelSize : 0.0;
}

qreal QRawFont::unitsPerEm() const
{
    return d->isValid() ? d->fontEngine->emSquareSize().toReal() : 0.0;
}

QString QRawFont::familyName() const
{
    return d->isValid() ? d->fontEngine->fontDef.family : QString();
}

QString QRawFont::styleName() const
{
    return d->isValid() ? d->fontEngine->fontDef.styleName : QString();
}

QFont::Style QRawFont::style() const
{
    return d->isValid() ? QFont::Style(d->fontEngine->fontDef.style) : QFont::StyleNormal;
}

int QRawFont::weight() const
{
    return d->isValid() ? int(d->fontEngine->fontDef.weight) : -1;
}

QVector<quint32> QRawFont::glyphIndexesForString(const QString &text) const
{
    if (!d->isValid())
        return QVector<quint32>();

    int nglyphs = text.size();
    QVarLengthGlyphLayoutArray glyphs(nglyphs);
    if (!glyphIndexesForChars(text.data(), text.size(), glyphs.glyphs, &nglyphs)) {
        glyphs.resize(nglyphs);
        if (!glyphIndexesForChars(text.data(), text.size(), glyphs.glyphs, &nglyphs)) {
            Q_ASSERT_X(false, Q_FUNC_INFO, "stringToCMap shouldn't fail twice");
            return QVector<quint32>();
        }
    }

    QVector<quint32> glyphIndexes;
    for (int i=0; i<nglyphs; ++i)
        glyphIndexes.append(glyphs.glyphs[i]);

    return glyphIndexes;
}

bool QRawFont::glyphIndexesForChars(const QChar *chars, int numChars, quint32 *glyphIndexes, int *numGlyphs) const
{
    if (!d->isValid())
        return false;

    QGlyphLayout glyphs;
    glyphs.glyphs = glyphIndexes;
    return d->fontEngine->stringToCMap(chars, numChars, &glyphs, numGlyphs, QTextEngine::GlyphIndicesOnly);
}

QVector<QPointF> QRawFont::advancesForGlyphIndexes(const QVector<quint32> &glyphIndexes) const
{
    if (!d->isValid())
        return QVector<QPointF>();

    int numGlyphs = glyphIndexes.size();
    QVarLengthGlyphLayoutArray glyphs(numGlyphs);
    qMemCopy(glyphs.glyphs, glyphIndexes.data(), numGlyphs * sizeof(quint32));

    d->fontEngine->recalcAdvances(&glyphs, 0);

    QVector<QPointF> advances;
    for (int i=0; i<numGlyphs; ++i)
        advances.append(QPointF(glyphs.advances_x[i].toReal(), glyphs.advances_y[i].toReal()));

    return advances;
}

bool QRawFont::advancesForGlyphIndexes(const quint32 *glyphIndexes, QPointF *advances, int numGlyphs) const
{
    if (!d->isValid())
        return false;

    QGlyphLayout glyphs;
    glyphs.glyphs = const_cast<HB_Glyph *>(glyphIndexes);
    glyphs.numGlyphs = numGlyphs;
    QVarLengthArray<QFixed> advances_x(numGlyphs);
    QVarLengthArray<QFixed> advances_y(numGlyphs);
    glyphs.advances_x = advances_x.data();
    glyphs.advances_y = advances_y.data();

    d->fontEngine->recalcAdvances(&glyphs, 0);

    for (int i=0; i<numGlyphs; ++i)
        advances[i] = QPointF(glyphs.advances_x[i].toReal(), glyphs.advances_y[i].toReal());

    return true;
}

QFont::HintingPreference QRawFont::hintingPreference() const
{
    return d->isValid() ? d->hintingPreference : QFont::PreferDefaultHinting;
}

QByteArray QRawFont::fontTable(const char *tagName) const
{
    if (!d->isValid())
        return QByteArray();

    const quint32 *tagId = reinterpret_cast<const quint32 *>(tagName);
    return d->fontEngine->getSfntTable(qToBigEndian(*tagId));
}

// From qfontdatabase.cpp
extern QList<QFontDatabase::WritingSystem> qt_determine_writing_systems_from_truetype_bits(quint32 unicodeRange[4], quint32 codePageRange[2]);

QList<QFontDatabase::WritingSystem> QRawFont::supportedWritingSystems() const
{
    if (d->isValid()) {
        QByteArray os2Table = fontTable("OS/2");
        if (os2Table.size() > 86) {
            char *data = os2Table.data();
            quint32 *bigEndianUnicodeRanges = reinterpret_cast<quint32 *>(data + 42);
            quint32 *bigEndianCodepageRanges = reinterpret_cast<quint32 *>(data + 78);

            quint32 unicodeRanges[4];
            quint32 codepageRanges[2];

            for (int i=0; i<4; ++i) {
                if (i < 2)
                    codepageRanges[i] = qFromBigEndian(bigEndianCodepageRanges[i]);
                unicodeRanges[i] = qFromBigEndian(bigEndianUnicodeRanges[i]);
            }

            return qt_determine_writing_systems_from_truetype_bits(unicodeRanges, codepageRanges);
        }
    }

    return QList<QFontDatabase::WritingSystem>();
}

bool QRawFont::supportsCharacter(QChar character) const
{
    return d->isValid() && d->fontEngine->canRender(&character, 1);
}

bool QRawFont::supportsCharacter(quint32 ucs4) const
{
    QChar str[2];
    int len;
    if (!QChar::requiresSurrogates(ucs4)) {
        str[0] = QChar(ucs4);
        len = 1;
    } else {
        str[0] = QChar(QChar::highSurrogate(ucs4));
        str[1] = QChar(QChar::lowSurrogate(ucs4));
        len = 2;
    }

    return d->isValid() && d->fontEngine->canRender(str, len);
}

// qfontdatabase.cpp
extern int qt_script_for_writing_system(QFontDatabase::WritingSystem writingSystem);

QRawFont QRawFont::fromFont(const QFont &font, QFontDatabase::WritingSystem writingSystem)
{
    QRawFont rawFont;
#if defined(Q_WS_MAC)
    QTextLayout layout(QFontDatabase::writingSystemSample(writingSystem), font);
    layout.beginLayout();
    QTextLine line = layout.createLine();
    layout.endLayout();
    QList<QGlyphRun> list = layout.glyphRuns();
    if (list.size()) {
        // Pick the one matches the family name we originally requested,
        // if none of them match, just pick the first one
        for (int i = 0; i < list.size(); i++) {
            rawFont = list.at(i).rawFont();
            if (rawFont.familyName() == font.family())
                return rawFont;
        }
        return list.at(0).rawFont();
    }
#else
    QFontPrivate *font_d = QFontPrivate::get(font);
    int script = qt_script_for_writing_system(writingSystem);
    QFontEngine *fe = font_d->engineForScript(script);

    if (fe != 0 && fe->type() == QFontEngine::Multi) {
        QFontEngineMulti *multiEngine = static_cast<QFontEngineMulti *>(fe);
        fe = multiEngine->engine(0);
        if (fe == 0) {
            multiEngine->loadEngine(0);
            fe = multiEngine->engine(0);
        }
    }

    if (fe != 0) {
        rawFont.d.data()->fontEngine = fe;
        rawFont.d.data()->fontEngine->ref.ref();
        rawFont.d.data()->hintingPreference = font.hintingPreference();
    }
#endif
    return rawFont;
}

void QRawFont::setPixelSize(qreal pixelSize)
{
    if (d->fontEngine == 0)
        return;

    d.detach();
    QFontEngine *oldFontEngine = d->fontEngine;

    d->fontEngine = d->fontEngine->cloneWithSize(pixelSize);
    if (d->fontEngine != 0)
        d->fontEngine->ref.ref();

    oldFontEngine->ref.deref();
    if (oldFontEngine->cache_count == 0 && oldFontEngine->ref == 0)
        delete oldFontEngine;
}

void QRawFontPrivate::cleanUp()
{
    platformCleanUp();
    if (fontEngine != 0) {
        fontEngine->ref.deref();
        if (fontEngine->cache_count == 0 && fontEngine->ref == 0)
            delete fontEngine;
        fontEngine = 0;
    }
    hintingPreference = QFont::PreferDefaultHinting;
}

QT_END_NAMESPACE

#endif // QT_NO_RAWFONT