qfontengine_qpf.cpp

奇趣公司比较新的qt/emd版本

    if (!fontData || fontData == (const uchar *)MAP_FAILED) {
#if defined(DEBUG_FONTENGINE)
        perror("mmap failed");
#endif
        fontData = 0;
        return;
    }

    if (!verifyHeader(fontData, st.st_size)) {
#if defined(DEBUG_FONTENGINE)
        qDebug() << "verifyHeader failed!";
#endif
        return;
    }

    const Header *header = reinterpret_cast<const Header *>(fontData);

    readOnly = (header->lock == 0xffffffff);

    const uchar *data = fontData + sizeof(Header) + qFromBigEndian<quint16>(header->dataSize);
    const uchar *endPtr = fontData + dataSize;
    while (data <= endPtr - 8) {
        quint16 blockTag = readValue<quint16>(data);
        data += 2; // skip padding
        quint32 blockSize = readValue<quint32>(data);

        if (blockTag == CMapBlock) {
            cmapOffset = data - fontData;
            cmapSize = blockSize;
        } else if (blockTag == GMapBlock) {
            glyphMapOffset = data - fontData;
            glyphMapEntries = blockSize / 4;
        } else if (blockTag == GlyphBlock) {
            glyphDataOffset = data - fontData;
            glyphDataSize = blockSize;
        }

        data += blockSize;
    }

    face_id.filename = QFile::encodeName(extractHeaderField(fontData, Tag_FileName).toString());
    face_id.index = extractHeaderField(fontData, Tag_FileIndex).toInt();
#if !defined(QT_NO_FREETYPE)
    freetype = QFreetypeFace::getFace(face_id);
    if (!freetype) {
        QString newPath =
#ifndef QT_NO_SETTINGS
            QLibraryInfo::location(QLibraryInfo::LibrariesPath) +
#endif
                          QLatin1String("/fonts/") +
                          QFileInfo(QFile::decodeName(face_id.filename)).fileName();
        face_id.filename = QFile::encodeName(newPath);
        freetype = QFreetypeFace::getFace(face_id);
    }
    if (freetype) {
        const quint32 qpfTtfRevision = extractHeaderField(fontData, Tag_FontRevision).toUInt();
        const QByteArray head = freetype->getSfntTable(MAKE_TAG('h', 'e', 'a', 'd'));
        if (head.size() < 8
            || qFromBigEndian<quint32>(reinterpret_cast<const uchar *>(head.constData()) + 4) != qpfTtfRevision) {
            freetype->release(face_id);
            freetype = 0;
        }
    }
    if (!cmapOffset && freetype) {
        freetypeCMapTable = freetype->getSfntTable(MAKE_TAG('c', 'm', 'a', 'p'));
        externalCMap = reinterpret_cast<const uchar *>(freetypeCMapTable.constData());
        cmapSize = freetypeCMapTable.size();
    }
#endif

    // get the real cmap
    if (cmapOffset) {
        int tableSize = cmapSize;
        const uchar *cmapPtr = getCMap(fontData + cmapOffset, tableSize, &symbol, &cmapSize);
        if (cmapPtr)
            cmapOffset = cmapPtr - fontData;
        else
            cmapOffset = 0;
    } else if (externalCMap) {
        int tableSize = cmapSize;
        externalCMap = getCMap(externalCMap, tableSize, &symbol, &cmapSize);
    }

    // verify all the positions in the glyphMap
    if (glyphMapOffset) {
        const quint32 *gmapPtr = reinterpret_cast<const quint32 *>(fontData + glyphMapOffset);
        for (uint i = 0; i < glyphMapEntries; ++i) {
            quint32 glyphDataPos = qFromBigEndian<quint32>(gmapPtr[i]);
            if (glyphDataPos == 0xffffffff)
                continue;
            if (glyphDataPos >= glyphDataSize) {
                // error
                glyphMapOffset = 0;
                glyphMapEntries = 0;
                break;
            }
        }
    }

#if defined(DEBUG_FONTENGINE)
    if (!isValid())
        qDebug() << "fontData" <<  fontData << "dataSize" << dataSize
                 << "externalCMap" << externalCMap << "cmapOffset" << cmapOffset
                 << "glyphMapOffset" << glyphMapOffset << "glyphDataOffset" << glyphDataOffset
                 << "fd" << fd << "glyphDataSize" << glyphDataSize;
#endif
#if defined(Q_WS_QWS)
    if (isValid() && renderingFontEngine)
        qt_fbdpy->sendFontCommand(QWSFontCommand::StartedUsingFont, QFile::encodeName(fileName));
#endif
}

QFontEngineQPF::~QFontEngineQPF()
{
#if defined(Q_WS_QWS)
    if (isValid() && renderingFontEngine)
        qt_fbdpy->sendFontCommand(QWSFontCommand::StoppedUsingFont, QFile::encodeName(fileName));
#endif
    delete renderingFontEngine;
    if (fontData)
        munmap((void *)fontData, dataSize);
    if (fd != -1)
        ::close(fd);
#if !defined(QT_NO_FREETYPE)
    delete _openType;
    _openType = 0;
    if (freetype)
        freetype->release(face_id);
#endif
}

QByteArray QFontEngineQPF::getSfntTable(uint tag) const
{
#if !defined(QT_NO_FREETYPE)
    if (freetype)
        return freetype->getSfntTable(tag);
#else
    Q_UNUSED(tag);
#endif
    return QByteArray();
}

bool QFontEngineQPF::stringToCMap(const QChar *str, int len, QGlyphLayout *glyphs, int *nglyphs, QTextEngine::ShaperFlags flags) const
{
    if (!externalCMap && !cmapOffset && renderingFontEngine) {
        if (!renderingFontEngine->stringToCMap(str, len, glyphs, nglyphs, flags))
            return false;
#ifndef QT_NO_FREETYPE
        const_cast<QFontEngineQPF *>(this)->ensureGlyphsLoaded(glyphs, *nglyphs);
#endif
        return true;
    }

    if (*nglyphs < len) {
        *nglyphs = len;
        return false;
    }

#if defined(DEBUG_FONTENGINE)
    QSet<QChar> seenGlyphs;
#endif

    const uchar *cmap = externalCMap ? externalCMap : (fontData + cmapOffset);

    int glyph_pos = 0;
    if (symbol) {
        for (int i = 0; i < len; ++i) {
            unsigned int uc = getChar(str, i, len);
            glyphs[glyph_pos].glyph = getTrueTypeGlyphIndex(cmap, uc);
            if(!glyphs[glyph_pos].glyph && uc < 0x100)
                glyphs[glyph_pos].glyph = getTrueTypeGlyphIndex(cmap, uc + 0xf000);
            ++glyph_pos;
        }
    } else {
        for (int i = 0; i < len; ++i) {
            unsigned int uc = getChar(str, i, len);
            glyphs[glyph_pos].glyph = getTrueTypeGlyphIndex(cmap, uc);
#if 0 && defined(DEBUG_FONTENGINE)
            QChar c(uc);
            if (!findGlyph(glyphs[glyph_pos].glyph) && !seenGlyphs.contains(c))
                qDebug() << "glyph for character" << c << "/" << hex << uc << "is" << dec << glyphs[glyph_pos].glyph;

            seenGlyphs.insert(c);
#endif
            ++glyph_pos;
        }
    }

    *nglyphs = glyph_pos;
    recalcAdvances(*nglyphs, glyphs, flags);
    return true;
}

void QFontEngineQPF::recalcAdvances(int len, QGlyphLayout *glyphs, QTextEngine::ShaperFlags) const
{
#ifndef QT_NO_FREETYPE
    const_cast<QFontEngineQPF *>(this)->ensureGlyphsLoaded(glyphs, len);
#endif
    for (int i = 0; i < len; ++i) {
        const Glyph *g = findGlyph(glyphs[i].glyph);
        if (!g) {
            glyphs[i].glyph = 0;
            continue;
        }
        glyphs[i].advance.x = g->advance;
        glyphs[i].advance.y = 0;
    }
}

void QFontEngineQPF::draw(QPaintEngine *p, qreal _x, qreal _y, const QTextItemInt &si)
{
    QPaintEngineState *pState = p->state;
    QRasterPaintEngine *paintEngine = static_cast<QRasterPaintEngine*>(p);

    QTransform matrix = pState->transform();
    matrix.translate(_x, _y);
    QFixed x = QFixed::fromReal(matrix.dx());
    QFixed y = QFixed::fromReal(matrix.dy());

    QVarLengthArray<QFixedPoint> positions;
    QVarLengthArray<glyph_t> glyphs;
    getGlyphPositions(si.glyphs, si.num_glyphs, matrix, si.flags, glyphs, positions);
    if (glyphs.size() == 0)
        return;

    for(int i = 0; i < glyphs.size(); i++) {
        const Glyph *glyph = findGlyph(glyphs[i]);
        if (!glyph)
            continue;

        const bool mono = false; // ###

        paintEngine->alphaPenBlt(reinterpret_cast<const uchar *>(glyph) + sizeof(Glyph), glyph->bytesPerLine, mono,
                                     qRound(positions[i].x) + glyph->x,
                                     qRound(positions[i].y) + glyph->y,
                                     glyph->width, glyph->height);
    }
}

void QFontEngineQPF::addOutlineToPath(qreal x, qreal y, const QGlyphLayout *glyphs, int numGlyphs, QPainterPath *path, QTextItem::RenderFlags flags)
{
    if (renderingFontEngine &&
        (renderingFontEngine->type() != QFontEngine::Proxy
         || static_cast<QProxyFontEngine *>(renderingFontEngine)->capabilities() & QAbstractFontEngine::CanOutlineGlyphs)) {
        renderingFontEngine->addOutlineToPath(x, y, glyphs, numGlyphs, path, flags);
        return;
    }
    addBitmapFontToPath(x, y, glyphs, numGlyphs, path, flags);
}

glyph_metrics_t QFontEngineQPF::boundingBox(const QGlyphLayout *glyphs, int numGlyphs)
{
#ifndef QT_NO_FREETYPE
    const_cast<QFontEngineQPF *>(this)->ensureGlyphsLoaded(glyphs, numGlyphs);
#endif

    glyph_metrics_t overall;
    // initialize with line height, we get the same behaviour on all platforms
    overall.y = -ascent();
    overall.height = ascent() + descent() + 1;

    QFixed ymax = 0;
    QFixed xmax = 0;
    for (int i = 0; i < numGlyphs; i++) {
        const Glyph *g = findGlyph(glyphs[i].glyph);
        if (!g)
            continue;

        QFixed x = overall.xoff + glyphs[i].offset.x + g->x;
        QFixed y = overall.yoff + glyphs[i].offset.y + g->y;
        overall.x = qMin(overall.x, x);
        overall.y = qMin(overall.y, y);
        xmax = qMax(xmax, x + g->width);
        ymax = qMax(ymax, y + g->height);
        overall.xoff += g->advance;
    }
    overall.height = qMax(overall.height, ymax - overall.y);
    overall.width = xmax - overall.x;

    return overall;
}

glyph_metrics_t QFontEngineQPF::boundingBox(glyph_t glyph)
{
#ifndef QT_NO_FREETYPE
    {
        QGlyphLayout tmp;
        tmp.glyph = glyph;
        const_cast<QFontEngineQPF *>(this)->ensureGlyphsLoaded(&tmp, 1);
    }
#endif
    glyph_metrics_t overall;
    const Glyph *g = findGlyph(glyph);
    if (!g)
        return overall;
    overall.x = g->x;
    overall.y = g->y;
    overall.width = g->width;
    overall.height = g->height;
    overall.xoff = g->advance;
    return overall;
}

QFixed QFontEngineQPF::ascent() const
{
    return QFixed::fromReal(extractHeaderField(fontData, Tag_Ascent).value<qreal>());
}

QFixed QFontEngineQPF::descent() const
{
    return QFixed::fromReal(extractHeaderField(fontData, Tag_Descent).value<qreal>());
}

QFixed QFontEngineQPF::leading() const
{
    return QFixed::fromReal(extractHeaderField(fontData, Tag_Leading).value<qreal>());
}

qreal QFontEngineQPF::maxCharWidth() const
{
    return extractHeaderField(fontData, Tag_MaxCharWidth).value<qreal>();
}

qreal QFontEngineQPF::minLeftBearing() const
{
    return extractHeaderField(fontData, Tag_MinLeftBearing).value<qreal>();
}

qreal QFontEngineQPF::minRightBearing() const
{
    return extractHeaderField(fontData, Tag_MinRightBearing).value<qreal>();
}

QFixed QFontEngineQPF::underlinePosition() const
{
    return QFixed::fromReal(extractHeaderField(fontData, Tag_UnderlinePosition).value<qreal>());
}

QFixed QFontEngineQPF::lineThickness() const
{
    return QFixed::fromReal(extractHeaderField(fontData, Tag_LineThickness).value<qreal>());
}

QFontEngine::Type QFontEngineQPF::type() const
{
    return QFontEngine::QPF2;
}

bool QFontEngineQPF::canRender(const QChar *string, int len)
{
    const uchar *cmap = externalCMap ? externalCMap : (fontData + cmapOffset);

    if (symbol) {
        for (int i = 0; i < len; ++i) {
            unsigned int uc = getChar(string, i, len);
            glyph_t g = getTrueTypeGlyphIndex(cmap, uc);
            if(!g && uc < 0x100)
                g = getTrueTypeGlyphIndex(cmap, uc + 0xf000);
            if (!g)
                return false;
        }
    } else {
        for (int i = 0; i < len; ++i) {
            unsigned int uc = getChar(string, i, len);
            if (!getTrueTypeGlyphIndex(cmap, uc))
                return false;
        }
    }
    return true;
}

bool QFontEngineQPF::isValid() const
{
    return fontData && dataSize && (cmapOffset || externalCMap || renderingFontEngine)
           && glyphMapOffset && glyphDataOffset && (fd >= 0 || glyphDataSize > 0);
}

#if !defined(QT_NO_FREETYPE)
FT_Face QFontEngineQPF::lockFace() const
{