qfontsubset.cpp

奇趣公司比较新的qt/emd版本

    // head table
    font.head.font_revision = 0x00010000;
    font.head.flags = (1 << 2) | (1 << 4);
    font.head.created = 0; // ###
    font.head.modified = 0; // ###
    font.head.xMin = SHRT_MAX;
    font.head.xMax = SHRT_MIN;
    font.head.yMin = SHRT_MAX;
    font.head.yMax = SHRT_MIN;
    font.head.macStyle = (fontEngine->fontDef.weight > QFont::Normal) ? 1 : 0;
    font.head.macStyle |= (fontEngine->fontDef.styleHint != QFont::StyleNormal) ? 1 : 0;

    // hhea table
    font.hhea.ascender = qRound(properties.ascent);
    font.hhea.descender = -qRound(properties.descent);
    font.hhea.lineGap = qRound(properties.leading);
    font.hhea.maxAdvanceWidth = TO_TTF(fontEngine->maxCharWidth());
    font.hhea.minLeftSideBearing = TO_TTF(fontEngine->minLeftBearing());
    font.hhea.minRightSideBearing = TO_TTF(fontEngine->minRightBearing());
    font.hhea.xMaxExtent = SHRT_MIN;

    font.maxp.numGlyphs = 0;
    font.maxp.maxPoints = 0;
    font.maxp.maxContours = 0;
    font.maxp.maxCompositePoints = 0;
    font.maxp.maxCompositeContours = 0;
    font.maxp.maxComponentElements = 0;
    font.maxp.maxComponentDepth = 0;
    font.maxp.numGlyphs = nGlyphs();



    uint sumAdvances = 0;
    for (int i = 0; i < nGlyphs(); ++i) {
        glyph_t g = glyph_indices.at(i);
        QPainterPath path;
        glyph_metrics_t metric;
        fontEngine->getUnscaledGlyph(g, &path, &metric);
        if (noEmbed) {
            path = QPainterPath();
            if (g == 0)
                path.addRect(QRectF(0, 0, 1000, 1000));
        }
        QTtfGlyph glyph = generateGlyph(i, path, metric.xoff.toReal(), metric.x.toReal(), properties.emSquare.toReal());

        font.head.xMin = qMin(font.head.xMin, glyph.xMin);
        font.head.xMax = qMax(font.head.xMax, glyph.xMax);
        font.head.yMin = qMin(font.head.yMin, glyph.yMin);
        font.head.yMax = qMax(font.head.yMax, glyph.yMax);

        font.hhea.xMaxExtent = qMax(font.hhea.xMaxExtent, (qint16)(glyph.lsb + glyph.xMax - glyph.xMin));

        font.maxp.maxPoints = qMax(font.maxp.maxPoints, glyph.numPoints);
        font.maxp.maxContours = qMax(font.maxp.maxContours, glyph.numContours);

        if (glyph.xMax > glyph.xMin)
            sumAdvances += glyph.xMax - glyph.xMin;

//         qDebug("adding glyph %d size=%d", glyph.index, glyph.data.size());
        glyphs.append(glyph);
        widths[i] = glyph.advanceWidth;
    }


    QList<QTtfTable> tables = generateGlyphTables(font, glyphs);
    tables.append(generateHead(font.head));
    tables.append(generateHhea(font.hhea));
    tables.append(generateMaxp(font.maxp));
    // name
    QTtfTable name_table;
    name_table.tag = MAKE_TAG('n', 'a', 'm', 'e');
    if (!noEmbed)
        name_table.data = fontEngine->getSfntTable(name_table.tag);
    if (name_table.data.isEmpty()) {
        qttf_name_table name;
        if (noEmbed)
            name.copyright = QLatin1String("Fake font");
        else
            name.copyright = QLatin1String(properties.copyright);
        name.family = fontEngine->fontDef.family;
        name.subfamily = QLatin1String("Regular"); // ######
        name.postscript_name = QLatin1String(properties.postscriptName);
        name_table = generateName(name);
    }
    tables.append(name_table);

    if (!noEmbed) {
        QTtfTable os2;
        os2.tag = MAKE_TAG('O', 'S', '/', '2');
        os2.data = fontEngine->getSfntTable(os2.tag);
        if (!os2.data.isEmpty())
            tables.append(os2);
    }

    return bindFont(tables);
}

// ------------------ Type 1 generation ---------------------------

// needs at least 6 bytes of space in tmp
static const char *encodeNumber(int num, char *tmp)
{
    const char *ret = tmp;
    if(num >= -107 && num <= 107) {
        QPdf::toHex((uchar)(num + 139), tmp);
        tmp += 2;
    } else if (num > 107 && num <= 1131) {
        num -= 108;
        QPdf::toHex((uchar)((num >> 8) + 247), tmp);
        tmp += 2;
        QPdf::toHex((uchar)(num & 0xff), tmp);
        tmp += 2;
    } else if(num < - 107 && num >= -1131) {
        num += 108;
        num = -num;
        QPdf::toHex((uchar)((num >> 8) + 251), tmp);
        tmp += 2;
        QPdf::toHex((uchar)(num & 0xff), tmp);
        tmp += 2;
    } else {
        *tmp++ = 'f';
        *tmp++ = 'f';
        QPdf::toHex((uchar)(num >> 24), tmp);
        tmp += 2;
        QPdf::toHex((uchar)(num >> 16), tmp);
        tmp += 2;
        QPdf::toHex((uchar)(num >> 8), tmp);
        tmp += 2;
        QPdf::toHex((uchar)(num >> 0), tmp);
        tmp += 2;
    }
    *tmp = 0;
//     qDebug("encodeNumber: %d -> '%s'", num, ret);
    return ret;
}

static QByteArray charString(const QPainterPath &path, qreal advance, qreal lsb, qreal ppem)
{
    // the charstring commands we need
    const char *hsbw = "0D";
    const char *closepath = "09";
    const char *moveto[3] = { "16", "04", "15" };
    const char *lineto[3] = { "06", "07", "05" };
    const char *rcurveto = "08";
    const char *endchar = "0E";

    enum { horizontal = 1,  vertical = 2 };

    char tmp[16];

    qreal factor = 1000./ppem;

    int lsb_i = qRound(lsb*factor);
    int advance_i = qRound(advance*factor);
//     qDebug("--- charstring");

    // first of all add lsb and width to the charstring using the hsbw command
    QByteArray charstring;
    charstring += encodeNumber(lsb_i, tmp);
    charstring += encodeNumber(advance_i, tmp);
    charstring += hsbw;

    // add the path
    int xl = lsb_i;
    int yl = 0;
    bool openpath = false;
    for (int i = 0; i < path.elementCount(); ++i) {
        const QPainterPath::Element &elm = path.elementAt(i);
        int x = qRound(elm.x*factor);
        int y = -qRound(elm.y*factor);
        int dx = x - xl;
        int dy = y - yl;
        if (elm.type == QPainterPath::MoveToElement && openpath) {
//             qDebug("closepath %s", closepath);
            charstring += closepath;
        }
        if (elm.type == QPainterPath::MoveToElement ||
            elm.type == QPainterPath::LineToElement) {
            int type = -1;
            if (dx || !dy) {
                charstring += encodeNumber(dx, tmp);
                type += horizontal;
//                 qDebug("horizontal");
            }
            if (dy) {
                charstring += encodeNumber(dy, tmp);
                type += vertical;
//                 qDebug("vertical");
            }
//             qDebug("moveto/lineto %s", (elm.type == QPainterPath::MoveToElement ? moveto[type] : lineto[type]));
            charstring += (elm.type == QPainterPath::MoveToElement ? moveto[type] : lineto[type]);
            openpath = true;
            xl = x;
            yl = y;
        } else {
            Q_ASSERT(elm.type == QPainterPath::CurveToElement);
            const QPainterPath::Element &elm2 = path.elementAt(++i);
            const QPainterPath::Element &elm3 = path.elementAt(++i);
            int x2 = qRound(elm2.x*factor);
            int y2 = -qRound(elm2.y*factor);
            int x3 = qRound(elm3.x*factor);
            int y3 = -qRound(elm3.y*factor);
            charstring += encodeNumber(dx, tmp);
            charstring += encodeNumber(dy, tmp);
            charstring += encodeNumber(x2 - x, tmp);
            charstring += encodeNumber(y2 - y, tmp);
            charstring += encodeNumber(x3 - x2, tmp);
            charstring += encodeNumber(y3 - y2, tmp);
            charstring += rcurveto;
            openpath = true;
            xl = x3;
            yl = y3;
//             qDebug("rcurveto");
        }
    }
    if (openpath)
        charstring += closepath;
    charstring += endchar;
    if (charstring.length() > 240) {
        int pos = 240;
        while (pos < charstring.length()) {
            charstring.insert(pos, '\n');
            pos += 241;
        }
    }
    return charstring;
}

#ifndef QT_NO_FREETYPE
static const char *helvetica_styles[4] = {
    "Helvetica",
    "Helvetica-Bold",
    "Helvetica-Oblique",
    "Helvetica-BoldOblique"
};
static const char *times_styles[4] = {
    "Times-Regular",
    "Times-Bold",
    "Times-Italic",
    "Times-BoldItalic"
};
static const char *courier_styles[4] = {
    "Courier",
    "Courier-Bold",
    "Courier-Oblique",
    "Courier-BoldOblique"
};
#endif

QByteArray QFontSubset::toType1() const
{
    QFontEngine::Properties properties = fontEngine->properties();
    QVector<int> reverseMap = getReverseMap();

    QByteArray font;
    QPdf::ByteStream s(&font);

    QByteArray id = QByteArray::number(object_id);
    QByteArray psname = properties.postscriptName;
    psname.replace(" ", "");

    standard_font = false;

#ifndef QT_NO_FREETYPE
    FT_Face face = ft_face(fontEngine);
    if (face && !FT_IS_SCALABLE(face)) {
        int style = 0;
        if (fontEngine->fontDef.style)
            style += 2;
        if (fontEngine->fontDef.weight >= QFont::Bold)
            style++;
        if (fontEngine->fontDef.family.contains(QLatin1String("Helvetica"))) {
            psname = helvetica_styles[style];
            standard_font = true;
        } else if (fontEngine->fontDef.family.contains(QLatin1String("Times"))) {
            psname = times_styles[style];
            standard_font = true;
        } else if (fontEngine->fontDef.family.contains(QLatin1String("Courier"))) {
            psname = courier_styles[style];
            standard_font = true;
        }
    }
#endif
    s << "/F" << id << "-Base\n";
    if (standard_font) {
            s << "/" << psname << " findfont\n"
                "0 dict copy dup /NumGlyphs 0 put dup /CMap 256 array put def\n";
    } else {
        s << "<<\n";
        if(!psname.isEmpty())
            s << "/FontName /" << psname << "\n";
        s << "/FontInfo <</FsType " << (int)fontEngine->fsType << ">>\n"
            "/FontType 1\n"
            "/PaintType 0\n"
            "/FontMatrix [.001 0 0 .001 0 0]\n"
            "/FontBBox { 0 0 0 0 }\n"
            "/Private <<\n"
            "/password 5839\n"
            "/MinFeature {16 16}\n"
            "/BlueValues []\n"
            "/lenIV -1\n"
            ">>\n"
            "/CharStrings << >>\n"
            "/NumGlyphs 0\n"
            "/CMap 256 array\n"
            ">> def\n";
    }
    s << type1AddedGlyphs();
    downloaded_glyphs = glyph_indices.size();

    return font;
}

QByteArray QFontSubset::type1AddedGlyphs() const
{
    if (downloaded_glyphs == glyph_indices.size())
        return QByteArray();

    QFontEngine::Properties properties = fontEngine->properties();
    QVector<int> reverseMap = getReverseMap();
    QByteArray glyphs;
    QPdf::ByteStream s(&glyphs);

    int nGlyphs = glyph_indices.size();
    QByteArray id = QByteArray::number(object_id);

    s << "F" << id << "-Base [\n";
    for (int i = downloaded_glyphs; i < nGlyphs; ++i) {
        glyph_t g = glyph_indices.at(i);
        QPainterPath path;
        glyph_metrics_t metric;
        fontEngine->getUnscaledGlyph(g, &path, &metric);
        QByteArray charstring = ::charString(path, metric.xoff.toReal(), metric.x.toReal(),
                                             properties.emSquare.toReal());
        s << glyphName(i, reverseMap);
        if (!standard_font)
          s << "\n<" << charstring << ">\n";
    }
    s << (standard_font ? "] T1AddMapping\n" : "] T1AddGlyphs\n");
    return glyphs;
}

#endif