qtextengine.cpp

奇趣公司比较新的qt/emd版本

        }
    }

    QFixed need = line.width - line.textWidth;
    if (need < 0) {
        // line overflows already!
        const_cast<QScriptLine &>(line).justified = true;
        return;
    }

//     qDebug("doing justification: textWidth=%x, requested=%x, maxJustify=%d", line.textWidth.value(), line.width.value(), maxJustify);
//     qDebug("     minKashida=%f, need=%f", minKashida, need);

    // distribute in priority order
    if (maxJustify >= QGlyphLayout::Arabic_Normal) {
        while (need >= minKashida) {
            for (int type = maxJustify; need >= minKashida && type >= QGlyphLayout::Arabic_Normal; --type) {
                for (int i = 0; need >= minKashida && i < nPoints; ++i) {
                    if (justificationPoints[i].type == type && justificationPoints[i].kashidaWidth <= need) {
                        justificationPoints[i].glyph->nKashidas++;
                        // ############
                        justificationPoints[i].glyph->space_18d6 += justificationPoints[i].kashidaWidth.value();
                        need -= justificationPoints[i].kashidaWidth;
//                         qDebug("adding kashida type %d with width %x, neednow %x", type, justificationPoints[i].kashidaWidth, need.value());
                    }
                }
            }
        }
    }
    Q_ASSERT(need >= 0);
    if (!need)
        goto end;

    maxJustify = qMin(maxJustify, (int)QGlyphLayout::Space);
    for (int type = maxJustify; need != 0 && type > 0; --type) {
        int n = 0;
        for (int i = 0; i < nPoints; ++i) {
            if (justificationPoints[i].type == type)
                ++n;
        }
//          qDebug("number of points for justification type %d: %d", type, n);


        if (!n)
            continue;

        for (int i = 0; i < nPoints; ++i) {
            if (justificationPoints[i].type == type) {
                QFixed add = need/n;
//                  qDebug("adding %x to glyph %x", add.value(), justificationPoints[i].glyph->glyph);
                justificationPoints[i].glyph->space_18d6 = add.value();
                need -= add;
                --n;
            }
        }

        Q_ASSERT(!need);
    }
 end:
    const_cast<QScriptLine &>(line).justified = true;
}

void QScriptLine::setDefaultHeight(QTextEngine *eng)
{
    QFont f;
    QFontEngine *e;

    if (eng->block.docHandle() && eng->block.docHandle()->layout()) {
        f = eng->block.charFormat().font();
        // Make sure we get the right dpi on printers
        QPaintDevice *pdev = eng->block.docHandle()->layout()->paintDevice();
        if (pdev)
            f = QFont(f, pdev);
        e = f.d->engineForScript(QUnicodeTables::Common);
    } else {
        e = eng->fnt.d->engineForScript(QUnicodeTables::Common);
    }

    ascent = qMax(ascent, e->ascent());
    descent = qMax(descent, e->descent());
}

QTextEngine::LayoutData::LayoutData()
{
    memory = 0;
    allocated = 0;
    num_glyphs = 0;
    memory_on_stack = false;
    used = 0;
    hasBidi = false;
    inLayout = false;
    haveCharAttributes = false;
    logClustersPtr = 0;
    glyphPtr = 0;
}

QTextEngine::LayoutData::LayoutData(const QString &str, void **stack_memory, int _allocated)
    : string(str)
{
    allocated = _allocated;

    int space_charAttributes = sizeof(QCharAttributes)*string.length()/sizeof(void*) + 1;
    int space_logClusters = sizeof(unsigned short)*string.length()/sizeof(void*) + 1;
    available_glyphs = ((int)allocated - space_charAttributes - space_logClusters)*(int)sizeof(void*)/(int)sizeof(QGlyphLayout);

    if (available_glyphs < str.length()) {
        // need to allocate on the heap
        num_glyphs = 0;
        allocated = 0;

        memory_on_stack = false;
        memory = 0;
        logClustersPtr = 0;
        glyphPtr = 0;
    } else {
        num_glyphs = str.length();

        memory_on_stack = true;
        memory = stack_memory;
        logClustersPtr = (unsigned short *)(memory + space_charAttributes);
        glyphPtr = (QGlyphLayout *)(memory + space_charAttributes + space_logClusters);
        memset(memory, 0, space_charAttributes*sizeof(void *));
        memset(glyphPtr, 0, num_glyphs*sizeof(QGlyphLayout));
    }
    used = 0;
    hasBidi = false;
    inLayout = false;
    haveCharAttributes = false;
}

QTextEngine::LayoutData::~LayoutData()
{
    if (!memory_on_stack)
        free(memory);
    memory = 0;
}

void QTextEngine::LayoutData::reallocate(int totalGlyphs)
{
    Q_ASSERT(totalGlyphs >= num_glyphs);
    if (memory_on_stack && available_glyphs >= totalGlyphs) {
        memset(glyphPtr + num_glyphs, 0, (totalGlyphs - num_glyphs)*sizeof(QGlyphLayout));
        num_glyphs = totalGlyphs;
        return;
    }

    int space_charAttributes = sizeof(QCharAttributes)*string.length()/sizeof(void*) + 1;
    int space_logClusters = sizeof(unsigned short)*string.length()/sizeof(void*) + 1;
    int space_glyphs = sizeof(QGlyphLayout)*totalGlyphs/sizeof(void*) + 2;

    int newAllocated = space_charAttributes + space_glyphs + space_logClusters;
    Q_ASSERT(newAllocated >= allocated);
    void **old_mem = memory;
    memory = (void **)::realloc(memory_on_stack ? 0 : old_mem, newAllocated*sizeof(void *));
    if (memory_on_stack && memory)
        memcpy(memory, old_mem, allocated*sizeof(void *));
    memory_on_stack = false;

    void **m = memory;
    m += space_charAttributes;
    logClustersPtr = (unsigned short *) m;
    m += space_logClusters;

    glyphPtr = (QGlyphLayout *) m;

    memset(((char *)memory) + allocated*sizeof(void *), 0,
           (newAllocated - allocated)*sizeof(void *));

    allocated = newAllocated;
    num_glyphs = totalGlyphs;
}

void QTextEngine::freeMemory()
{
    if (!stackEngine) {
        delete layoutData;
        layoutData = 0;
    } else {
        layoutData->used = 0;
        layoutData->hasBidi = false;
        layoutData->inLayout = false;
        layoutData->haveCharAttributes = false;
    }
    for (int i = 0; i < lines.size(); ++i) {
        lines[i].justified = 0;
        lines[i].gridfitted = 0;
    }
}

int QTextEngine::formatIndex(const QScriptItem *si) const
{
    if (specialData && !specialData->resolvedFormatIndices.isEmpty())
        return specialData->resolvedFormatIndices.at(si - &layoutData->items[0]);
    QTextDocumentPrivate *p = block.docHandle();
    if (!p)
        return -1;
    int pos = si->position;
    if (specialData && si->position >= specialData->preeditPosition) {
        if (si->position < specialData->preeditPosition + specialData->preeditText.length())
            pos = qMax(specialData->preeditPosition - 1, 0);
        else
            pos -= specialData->preeditText.length();
    }
    QTextDocumentPrivate::FragmentIterator it = p->find(block.position() + pos);
    return it.value()->format;
}


QTextCharFormat QTextEngine::format(const QScriptItem *si) const
{
    QTextCharFormat format;
    const QTextFormatCollection *formats = 0;
    if (block.docHandle()) {
        formats = this->formats();
        format = formats->charFormat(formatIndex(si));
    }
    if (specialData && specialData->resolvedFormatIndices.isEmpty()) {
        int end = si->position + length(si);
        for (int i = 0; i < specialData->addFormats.size(); ++i) {
            const QTextLayout::FormatRange &r = specialData->addFormats.at(i);
            if (r.start <= si->position && r.start + r.length >= end) {
                if (!specialData->addFormatIndices.isEmpty())
                    format.merge(formats->format(specialData->addFormatIndices.at(i)));
                else
                    format.merge(r.format);
            }
        }
    }
    return format;
}

void QTextEngine::addRequiredBoundaries() const
{
    int position = 0;
    SpecialData *s = specialData;

    const QTextDocumentPrivate *p = block.docHandle();
    if (p) {
        QTextDocumentPrivate::FragmentIterator it = p->find(block.position());
        QTextDocumentPrivate::FragmentIterator end = p->find(block.position() + block.length() - 1); // -1 to omit the block separator char
        int format = it.value()->format;

        for (; it != end; ++it) {
            if (s && position >= s->preeditPosition) {
                position += s->preeditText.length();
                s = 0;
            }
            const QTextFragmentData * const frag = it.value();
            if (format != frag->format)
                setBoundary(position);
            format = frag->format;
            position += frag->size;
        }
    }
    if (specialData) {
        for (int i = 0; i < specialData->addFormats.size(); ++i) {
            const QTextLayout::FormatRange &r = specialData->addFormats.at(i);
            setBoundary(r.start);
            setBoundary(r.start + r.length);
            //qDebug("adding boundaries %d %d", r.start, r.start+r.length);
        }
    }
}

bool QTextEngine::atWordSeparator(int position) const
{
    const QChar c = layoutData->string.at(position);
    return c == QLatin1Char('.')
        || c == QLatin1Char(',')
        || c == QLatin1Char('?')
        || c == QLatin1Char('!')
        || c == QLatin1Char(':')
        || c == QLatin1Char(';')
        || c == QLatin1Char('-')
        || c == QLatin1Char('<')
        || c == QLatin1Char('>')
        || c == QLatin1Char('[')
        || c == QLatin1Char(']')
        || c == QLatin1Char('(')
        || c == QLatin1Char(')')
        || c == QLatin1Char('{')
        || c == QLatin1Char('}')
        || c == QLatin1Char('=')
        || c == QLatin1Char('\t')
        || c == QChar::Nbsp
        ;
}

void QTextEngine::indexAdditionalFormats()
{
    if (!block.docHandle())
        return;

    specialData->addFormatIndices.resize(specialData->addFormats.count());
    QTextFormatCollection * const formats = this->formats();

    for (int i = 0; i < specialData->addFormats.count(); ++i) {
        specialData->addFormatIndices[i] = formats->indexForFormat(specialData->addFormats.at(i).format);
        specialData->addFormats[i].format = QTextCharFormat();
    }
}

QString QTextEngine::elidedText(Qt::TextElideMode mode, const QFixed &width, int flags) const
{
//    qDebug() << "elidedText; available width" << width.toReal() << "text width:" << this->width(0, layoutData->string.length()).toReal();

    if (flags & Qt::TextShowMnemonic) {
        itemize();
        for (int i = 0; i < layoutData->items.size(); ++i) {
            QScriptItem &si = layoutData->items[i];
            if (!si.num_glyphs)
                shape(i);

            unsigned short *logClusters = this->logClusters(&si);
            QGlyphLayout *glyphs = this->glyphs(&si);

            const int end = si.position + length(&si);
            for (int i = si.position; i < end - 1; ++i)
                if (layoutData->string.at(i) == QLatin1Char('&')) {
                    const int gp = logClusters[i - si.position];
                    glyphs[gp].attributes.dontPrint = true;
                    QCharAttributes *attributes = const_cast<QCharAttributes *>(this->attributes());
                    attributes[i + 1].charStop = false;
                    attributes[i + 1].whiteSpace = false;
                    attributes[i + 1].lineBreakType = QCharAttributes::NoBreak;
                    if (i < end - 1
                            && layoutData->string.at(i + 1) == QLatin1Char('&'))
                        ++i;
                }
        }
    }

    validate();

    if (mode == Qt::ElideNone
        || this->width(0, layoutData->string.length()) <= width
        || layoutData->string.length() <= 1)
        return layoutData->string;

    QFixed ellipsisWidth;
    QString ellipsisText;
    {
        QChar ellipsisChar(0x2026);

        QFontEngine *fe = fnt.d->engineForScript(QUnicodeTables::Common);
        // the lookup can be really slow when we use XLFD fonts
        bool isXlfdEngine = (fe->type() == QFontEngine::XLFD)
                            || (fe->type() == QFontEngine::Multi
                                && static_cast<QFontEngineMulti*>(fe)->engine(0)->type() == QFontEngine::XLFD);
        if (!isXlfdEngine && fe->canRender(&ellipsisChar, 1)) {
            QGlyphLayout glyph;
            int nGlyphs = 1;
            fe->stringToCMap(&ellipsisChar, 1, &glyph, &nGlyphs, 0);
            ellipsisWidth = glyph.advance.x;
            ellipsisText = ellipsisChar;
        } else {
            QString dotDotDot(QLatin1String("..."));

            QGlyphLayout glyphs[3];
            int