qtextengine.cpp

qt-x11-opensource-src-4.1.4.tar.gz源码

            case QGlyphLayout::Arabic_Space   :
                if (kashida_pos >= 0) {
//                     qDebug("kashida position at %d in word", kashida_pos);
                    set(&justificationPoints[nPoints], kashida_type, g+kashida_pos, fontEngine(si));
                    minKashida = qMin(minKashida, justificationPoints[nPoints].kashidaWidth);
                    maxJustify = qMax(maxJustify, justificationPoints[nPoints].type);
                    ++nPoints;
                }
                kashida_pos = -1;
                kashida_type = QGlyphLayout::Arabic_Normal;
                // fall through
            case QGlyphLayout::Character      :
                set(&justificationPoints[nPoints++], justification, g+i, fontEngine(si));
                maxJustify = qMax(maxJustify, justification);
                break;
            case QGlyphLayout::Arabic_Normal  :
            case QGlyphLayout::Arabic_Waw     :
            case QGlyphLayout::Arabic_BaRa    :
            case QGlyphLayout::Arabic_Alef    :
            case QGlyphLayout::Arabic_HaaDal  :
            case QGlyphLayout::Arabic_Seen    :
            case QGlyphLayout::Arabic_Kashida :
                if (justification >= kashida_type) {
                    kashida_pos = i;
                    kashida_type = justification;
                }
            }
        }
        if (kashida_pos >= 0) {
            set(&justificationPoints[nPoints], kashida_type, g+kashida_pos, fontEngine(si));
            minKashida = qMin(minKashida, justificationPoints[nPoints].kashidaWidth);
            maxJustify = qMax(maxJustify, justificationPoints[nPoints].type);
            ++nPoints;
        }
    }

    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()) {
        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) - 2;

    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();
        allocated = 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;
    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 == '.'
        || c == ','
        || c == ':'
        || c == ';'
        || c == '-'
        || c == '<'
        || c == '>'
        || c == '['
        || c == ']'
        || c == '('
        || c == ')'
        || c == '{'
        || c == '}'
        || 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();
    }
}

void QTextEngine::setBoundary(int strPos) const
{
    if (strPos <= 0 || strPos >= layoutData->string.length())
        return;

    int itemToSplit = 0;
    while (itemToSplit < layoutData->items.size() && layoutData->items[itemToSplit].position <= strPos)
        itemToSplit++;
    itemToSplit--;
    if (layoutData->items[itemToSplit].position == strPos) {
        // already a split at the requested position
        return;
    }
    splitItem(itemToSplit, strPos - layoutData->items[itemToSplit].position);
}

void QTextEngine::splitItem(int item, int pos) const
{
    if (pos <= 0)
        return;

    layoutData->items.insert(item + 1, QScriptItem(layoutData->items[item]));
    QScriptItem &oldItem = layoutData->items[item];
    QScriptItem &newItem = layoutData->items[item+1];
    newItem.position += pos;

    if (oldItem.num_glyphs) {
        // already shaped, break glyphs aswell
        int breakGlyph = logClusters(&oldItem)[pos];

        newItem.num_glyphs = oldItem.num_glyphs - breakGlyph;
        oldItem.num_glyphs = breakGlyph;
        newItem.glyph_data_offset = oldItem.glyph_data_offset + breakGlyph;

        for (int i = 0; i < newItem.num_glyphs; i++)
            logClusters(&newItem)[i] -= breakGlyph;

        QFixed w = 0;
        const QGlyphLayout *g = glyphs(&oldItem);
        for(int j = 0; j < breakGlyph; ++j)
            w += (g++)->advance.x;

        newItem.width = oldItem.width - w;
        oldItem.width = w;
    }

//     qDebug("split at position %d itempos=%d", pos, item);
}

QFixed QTextEngine::nextTab(const QScriptItem *si, QFixed x) const
{
    // #### should work for alignright and righttoleft
    if (!(option.alignment() & Qt::AlignLeft) ||
        option.textDirection() != Qt::LeftToRight)
        return x + si->width;

    QList<qreal> tabArray = option.tabArray();
    if (!tabArray.isEmpty()) {
        for (int i = 0; i < tabArray.size(); ++i) {
            if (tabArray.at(i) > x.toReal())
                return QFixed::fromReal(tabArray.at(i));
        }
    }
    QFixed tab = QFixed::fromReal(option.tabStop());
    if (tab <= 0)
        tab = 80; // default
    return ((x / tab).truncate() + 1) * tab;
}

void QTextEngine::resolveAdditionalFormats() const
{
    if (!specialData || specialData->addFormats.isEmpty()
        || !block.docHandle())
        return;

    QTextFormatCollection *collection = this->formats();

    specialData->resolvedFormatIndices.clear();
    QVector<int> indices(layoutData->items.count());
    for (int i = 0; i < layoutData->items.count(); ++i) {
        QTextCharFormat f = format(&layoutData->items.at(i));
        indices[i] = collection->indexForFormat(f);
    }
    specialData->resolvedFormatIndices = indices;
}

QStackTextEngine::QStackTextEngine(const QString &string, const QFont &f)
    : _layoutData(string, _memory, MemSize)
{
    fnt = f;
    text = string;
    stackEngine = true;
    layoutData = &_layoutData;
}