qtextengine.cpp

qt-x11-opensource-src-4.1.4.tar.gz源码

    e->specialData = 0;
    e->stackEngine = false;
}

QTextEngine::QTextEngine()
{
    init(this);
}

QTextEngine::QTextEngine(const QString &str, const QFont &f)
    : fnt(f)
{
    init(this);
    text = str;
}

QTextEngine::~QTextEngine()
{
    if (!stackEngine)
        delete layoutData;
    delete specialData;
}

const QCharAttributes *QTextEngine::attributes() const
{
    if (layoutData && layoutData->haveCharAttributes)
        return (QCharAttributes *) layoutData->memory;

    itemize();
    ensureSpace(layoutData->string.length());
    
    calcLineBreaks(layoutData->string, (QCharAttributes *) layoutData->memory);

    for (int i = 0; i < layoutData->items.size(); i++) {
        const QScriptItem &si = layoutData->items[i];
        int script = si.analysis.script;
#ifdef Q_WS_WIN
        if(hasUsp10) {
            script = QUnicodeTables::script(layoutData->string.at(si.position));
        }
#endif
        if (script == QUnicodeTables::Inherited)
            script = QUnicodeTables::Common;
        AttributeFunction attributes = qt_scriptEngines[script].charAttributes;
        if (!attributes)
            continue;
        int from = si.position;
        int len = length(i);
        attributes(script, layoutData->string, from, len, (QCharAttributes *) layoutData->memory);
    }
    
    layoutData->haveCharAttributes = true;
    return (QCharAttributes *) layoutData->memory;
}

void QTextEngine::shape(int item) const
{
    if (layoutData->items[item].isObject) {
        ensureSpace(1);
        if (block.docHandle()) {
            QTextFormat format = formats()->format(formatIndex(&layoutData->items[item]));
            docLayout()->resizeInlineObject(QTextInlineObject(item, const_cast<QTextEngine *>(this)),
                                            layoutData->items[item].position + block.position(), format);
        }
    } else {
        shapeText(item);
    }
}

void QTextEngine::invalidate()
{
    freeMemory();
    lines.clear();
    minWidth = 0;
    maxWidth = 0;
    if (specialData)
        specialData->resolvedFormatIndices.clear();
}

void QTextEngine::validate() const
{
    if (layoutData)
        return;
    layoutData = new LayoutData();
    if (block.docHandle())
        layoutData->string = block.text();
    else
        layoutData->string = text;
    if (specialData && specialData->preeditPosition != -1)
        layoutData->string.insert(specialData->preeditPosition, specialData->preeditText);
}


void QTextEngine::itemize() const
{
    validate();
    if (layoutData->items.size())
        return;

    if (layoutData->string.length() == 0)
        return;

    if (!ignoreBidi) {
        layoutData->hasBidi = bidiItemize(const_cast<QTextEngine *>(this), (option.textDirection() == Qt::RightToLeft));
    } else {
        QBidiControl control(false);
        int start = 0;
        int stop = layoutData->string.length() - 1;
        appendItems(const_cast<QTextEngine *>(this), start, stop, control, QChar::DirL);
    }

    addRequiredBoundaries();
    resolveAdditionalFormats();
}

int QTextEngine::findItem(int strPos) const
{
    itemize();

    // ##### use binary search
    int item;
    for (item = layoutData->items.size()-1; item > 0; --item) {
        if (layoutData->items[item].position <= strPos)
            break;
    }
    return item;
}

QFixed QTextEngine::width(int from, int len) const
{
    itemize();

    QFixed w = 0;

//     qDebug("QTextEngine::width(from = %d, len = %d), numItems=%d, strleng=%d", from,  len, items.size(), string.length());
    for (int i = 0; i < layoutData->items.size(); i++) {
        const QScriptItem *si = layoutData->items.constData() + i;
        int pos = si->position;
        int ilen = length(i);
//          qDebug("item %d: from %d len %d", i, pos, ilen);
        if (pos >= from + len)
            break;
        if (pos + ilen > from) {
            if (!si->num_glyphs)
                shape(i);
            
            if (si->isObject) {
                w += si->width;
                continue;
            } else if (si->isTab) {
                w = nextTab(si, w);
                continue;
            }

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

//             fprintf(stderr, "  logclusters:");
//             for (int k = 0; k < ilen; k++)
//                 fprintf(stderr, " %d", logClusters[k]);
//             fprintf(stderr, "\n");
            // do the simple thing for now and give the first glyph in a cluster the full width, all other ones 0.
            int charFrom = from - pos;
            if (charFrom < 0)
                charFrom = 0;
            int glyphStart = logClusters[charFrom];
            if (charFrom > 0 && logClusters[charFrom-1] == glyphStart)
                while (charFrom < ilen && logClusters[charFrom] == glyphStart)
                    charFrom++;
            if (charFrom < ilen) {
                glyphStart = logClusters[charFrom];
                int charEnd = from + len - 1 - pos;
                if (charEnd >= ilen)
                    charEnd = ilen-1;
                int glyphEnd = logClusters[charEnd];
                while (charEnd < ilen && logClusters[charEnd] == glyphEnd)
                    charEnd++;
                glyphEnd = (charEnd == ilen) ? si->num_glyphs : logClusters[charEnd];

//                 qDebug("char: start=%d end=%d / glyph: start = %d, end = %d", charFrom, charEnd, glyphStart, glyphEnd);
                for (int i = glyphStart; i < glyphEnd; i++)
                    w += glyphs[i].advance.x;
            }
        }
    }
//     qDebug("   --> w= %d ", w);
    return w;
}

glyph_metrics_t QTextEngine::boundingBox(int from,  int len) const
{
    itemize();

    glyph_metrics_t gm;

    for (int i = 0; i < layoutData->items.size(); i++) {
        const QScriptItem *si = layoutData->items.constData() + i;
        int pos = si->position;
        int ilen = length(i);
        if (pos > from + len)
            break;
        if (pos + len > from) {
            if (!si->num_glyphs)
                shape(i);
            unsigned short *logClusters = this->logClusters(si);
            QGlyphLayout *glyphs = this->glyphs(si);

            // do the simple thing for now and give the first glyph in a cluster the full width, all other ones 0.
            int charFrom = from - pos;
            if (charFrom < 0)
                charFrom = 0;
            int glyphStart = logClusters[charFrom];
            if (charFrom > 0 && logClusters[charFrom-1] == glyphStart)
                while (charFrom < ilen && logClusters[charFrom] == glyphStart)
                    charFrom++;
            if (charFrom < ilen) {
                glyphStart = logClusters[charFrom];
                int charEnd = from + len - 1 - pos;
                if (charEnd >= ilen)
                    charEnd = ilen-1;
                int glyphEnd = logClusters[charEnd];
                while (charEnd < ilen && logClusters[charEnd] == glyphEnd)
                    charEnd++;
                glyphEnd = (charEnd == ilen) ? si->num_glyphs : logClusters[charEnd];
                if (glyphStart <= glyphEnd ) {
                    QFontEngine *fe = fontEngine(*si);
                    glyph_metrics_t m = fe->boundingBox(glyphs+glyphStart, glyphEnd-glyphStart);
                    gm.x = qMin(gm.x, m.x + gm.xoff);
                    gm.y = qMin(gm.y, m.y + gm.yoff);
                    gm.width = qMax(gm.width, m.width+gm.xoff);
                    gm.height = qMax(gm.height, m.height+gm.yoff);
                    gm.xoff += m.xoff;
                    gm.yoff += m.yoff;
                }
            }
        }
    }
    return gm;
}

QFont QTextEngine::font(const QScriptItem &si) const
{
    if (!hasFormats())
        return fnt;
    QTextCharFormat f = format(&si);
    QFont font = f.font();

    if (block.docHandle()) {
        // Make sure we get the right dpi on printers
        QPaintDevice *pdev = block.docHandle()->layout()->paintDevice();
        if (pdev)
            font = QFont(font, pdev);
    } else {
        font = font.resolve(fnt);
    }

    if (f.verticalAlignment() != QTextCharFormat::AlignNormal)
        font.setPointSize((font.pointSize() * 2) / 3);

    return font;
}

QFontEngine *QTextEngine::fontEngine(const QScriptItem &si, QFixed *ascent, QFixed *descent) const
{
    QFontEngine *engine;
    QFontEngine *scaledEngine = 0;
    int script = si.analysis.script;
#if defined(Q_WS_WIN)
    if (hasUsp10) {
        const SCRIPT_PROPERTIES *script_prop = script_properties[si.analysis.script];
        script = scriptForWinLanguage(script_prop->langid);
    }
#endif
    
    if (!hasFormats()) {
        engine = fnt.d->engineForScript(script);
#if defined(Q_WS_WIN)
        if (engine->type() == QFontEngine::Box)
            engine = fnt.d->engineForScript(QUnicodeTables::Common);
#endif
    } else {
        QTextCharFormat f = format(&si);
        QFont font = f.font();

        if (block.docHandle()) {
            // Make sure we get the right dpi on printers
            QPaintDevice *pdev = block.docHandle()->layout()->paintDevice();
            if (pdev)
                font = QFont(font, pdev);
        } else {
            font = font.resolve(fnt);
        }
        engine = font.d->engineForScript(script);
#if defined(Q_WS_WIN)
        if (engine->type() == QFontEngine::Box)
            engine = font.d->engineForScript(QUnicodeTables::Common);
#endif
        if (f.verticalAlignment() != QTextCharFormat::AlignNormal) {
            font.setPointSize((font.pointSize() * 2) / 3);
            scaledEngine = font.d->engineForScript(script);
#if defined(Q_WS_WIN)
            if (scaledEngine->type() == QFontEngine::Box)
                scaledEngine = font.d->engineForScript(QUnicodeTables::Common);
#endif
        }
    }

    if (ascent) {
        *ascent = engine->ascent();
        *descent = engine->descent();
    }
    
    if (scaledEngine)
        return scaledEngine;
    return engine;
}

struct QJustificationPoint {
    int type;
    QFixed kashidaWidth;
    QGlyphLayout *glyph;
    QFontEngine *fontEngine;
};

Q_DECLARE_TYPEINFO(QJustificationPoint, Q_PRIMITIVE_TYPE);

static void set(QJustificationPoint *point, int type, QGlyphLayout *glyph, QFontEngine *fe)
{
    point->type = type;
    point->glyph = glyph;
    point->fontEngine = fe;

    if (type >= QGlyphLayout::Arabic_Normal) {
        QChar ch(0x640); // Kashida character
        QGlyphLayout glyphs[8];
        int nglyphs = 7;
        fe->stringToCMap(&ch, 1, glyphs, &nglyphs, 0);
        if (glyphs[0].glyph && glyphs[0].advance.x != 0) {
            point->kashidaWidth = glyphs[0].advance.x;
        } else {
            point->type = QGlyphLayout::NoJustification;
            point->kashidaWidth = 0;
        }
    }
}


void QTextEngine::justify(const QScriptLine &line)
{
//     qDebug("justify: line.gridfitted = %d, line.justified=%d", line.gridfitted, line.justified);
    if (line.gridfitted && line.justified)
        return;

    if (!line.gridfitted) {
        // redo layout in device metrics, then adjust
        const_cast<QScriptLine &>(line).gridfitted = true;
    }

    if ((option.alignment() & Qt::AlignHorizontal_Mask) != Qt::AlignJustify)
        return;

    itemize();

    if (line.from + (int)line.length == layoutData->string.length()
        || layoutData->string.at(line.from + line.length - 1) == QChar::LineSeparator)
        return;

    // justify line
    int maxJustify = 0;

    // don't include trailing white spaces when doing justification
    int line_length = line.length;
    const QCharAttributes *a = attributes()+line.from;
    while (line_length && a[line_length-1].whiteSpace)
        --line_length;
    // subtract one char more, as we can't justfy after the last character
    --line_length;

    if (!line_length)
        return;

    int firstItem = findItem(line.from);
    int nItems = findItem(line.from + line_length - 1) - firstItem + 1;

    QVarLengthArray<QJustificationPoint> justificationPoints;
    int nPoints = 0;
//     qDebug("justifying from %d len %d, firstItem=%d, nItems=%d", line.from, line_length, firstItem, nItems);
    QFixed minKashida = 0x100000;

    // we need to do all shaping before we go into the next loop, as we there
    // store pointers to the glyph data that could get reallocated by the shaping
    // process.
    for (int i = 0; i < nItems; ++i) {
        QScriptItem &si = layoutData->items[firstItem + i];
        if (!si.num_glyphs)
            shape(firstItem + i);
    }

    for (int i = 0; i < nItems; ++i) {
        QScriptItem &si = layoutData->items[firstItem + i];

        int kashida_type = QGlyphLayout::Arabic_Normal;
        int kashida_pos = -1;

        int start = qMax(line.from - si.position, 0);
        int end = qMin(line.from + line_length - (int)si.position, length(firstItem+i));

        unsigned short *log_clusters = logClusters(&si);

        int gs = log_clusters[start];
        int ge = (end == length(firstItem+i) ? si.num_glyphs : log_clusters[end]);

        QGlyphLayout *g = glyphs(&si);

        for (int i = gs; i < ge; ++i) {
            g[i].justificationType = QGlyphLayout::JustifyNone;
            g[i].nKashidas = 0;
            g[i].space_18d6 = 0;

            justificationPoints.resize(nPoints+3);
            int justification = g[i].attributes.justification;

            switch(justification) {
            case QGlyphLayout::NoJustification:
                break;
            case QGlyphLayout::Space          :
                // fall through