bidi.cpp

konqueror3 embedded版本, KDE环境下的当家浏览器的嵌入式版本源码包.

}

static void reverseRuns(int start, int end)
{
    if (start >= end)
        return;

    assert(start >= 0 && end < sBidiRunCount);

    // Get the item before the start of the runs to reverse and put it in
    // |beforeStart|.  |curr| should point to the first run to reverse.
    BidiRun* curr = sFirstBidiRun;
    BidiRun* beforeStart = 0;
    int i = 0;
    while (i < start) {
        i++;
        beforeStart = curr;
        curr = curr->nextRun;
    }

    BidiRun* startRun = curr;
    while (i < end) {
        i++;
        curr = curr->nextRun;
    }
    BidiRun* endRun = curr;
    BidiRun* afterEnd = curr->nextRun;

    i = start;
    curr = startRun;
    BidiRun* newNext = afterEnd;
    while (i <= end) {
        // Do the reversal.
        BidiRun* next = curr->nextRun;
        curr->nextRun = newNext;
        newNext = curr;
        curr = next;
        i++;
    }

    // Now hook up beforeStart and afterEnd to the newStart and newEnd.
    if (beforeStart)
        beforeStart->nextRun = endRun;
    else
        sFirstBidiRun = endRun;

    startRun->nextRun = afterEnd;
    if (!afterEnd)
        sLastBidiRun = startRun;
}

static void chopMidpointsAt(RenderObject* obj, uint pos)
{
    if (!sNumMidpoints) return;
    BidiIterator* midpoints = smidpoints->data();
    for (uint i = 0; i < sNumMidpoints; i++) {
        const BidiIterator& point = midpoints[i];
        if (point.obj == obj && point.pos == pos) {
            sNumMidpoints = i;
            break;
        }
    }
}

static void checkMidpoints(BidiIterator& lBreak, BidiState &bidi)
{
    // Check to see if our last midpoint is a start point beyond the line break.  If so,
    // shave it off the list, and shave off a trailing space if the previous end point isn't
    // white-space: pre.
    if (lBreak.obj && sNumMidpoints && sNumMidpoints%2 == 0) {
        BidiIterator* midpoints = smidpoints->data();
        BidiIterator& endpoint = midpoints[sNumMidpoints-2];
        const BidiIterator& startpoint = midpoints[sNumMidpoints-1];
        BidiIterator currpoint = endpoint;
        while (!currpoint.atEnd() && currpoint != startpoint && currpoint != lBreak)
            currpoint.increment( bidi );
        if (currpoint == lBreak) {
            // We hit the line break before the start point.  Shave off the start point.
            sNumMidpoints--;
            if (!endpoint.obj->style()->preserveWS()) {
                if (endpoint.obj->isText()) {
                    // Don't shave a character off the endpoint if it was from a soft hyphen.
                    RenderText* textObj = static_cast<RenderText*>(endpoint.obj);
                    if (endpoint.pos+1 < textObj->length() &&
                        textObj->text()[endpoint.pos+1].unicode() == SOFT_HYPHEN)
                        return;
                }
                endpoint.pos--;
            }
        }
    }
}

static void addMidpoint(const BidiIterator& midpoint)
{
    if (!smidpoints)
        return;

    if (smidpoints->size() <= sNumMidpoints)
        smidpoints->resize(sNumMidpoints+10);

    BidiIterator* midpoints = smidpoints->data();
    midpoints[sNumMidpoints++] = midpoint;
}

static void appendRunsForObject(int start, int end, RenderObject* obj, BidiState &bidi)
{
    if (start > end || obj->isFloating() ||
        (obj->isPositioned() && !obj->hasStaticX() && !obj->hasStaticY()))
        return;

    bool haveNextMidpoint = (smidpoints && sCurrMidpoint < sNumMidpoints);
    BidiIterator nextMidpoint;
    if (haveNextMidpoint)
        nextMidpoint = smidpoints->at(sCurrMidpoint);
    if (betweenMidpoints) {
        if (!(haveNextMidpoint && nextMidpoint.obj == obj))
            return;
        // This is a new start point. Stop ignoring objects and
        // adjust our start.
        betweenMidpoints = false;
        start = nextMidpoint.pos;
        sCurrMidpoint++;
        if (start < end)
            return appendRunsForObject(start, end, obj, bidi);
    }
    else {
        if (!smidpoints || !haveNextMidpoint || (obj != nextMidpoint.obj)) {
            addRun(new (obj->renderArena()) BidiRun(start, end, obj, bidi.context, dir));
            return;
        }

        // An end midpoint has been encountered within our object.  We
        // need to go ahead and append a run with our endpoint.
        if (int(nextMidpoint.pos+1) <= end) {
            betweenMidpoints = true;
            sCurrMidpoint++;
            if (nextMidpoint.pos != UINT_MAX) { // UINT_MAX means stop at the object and don't include any of it.
                addRun(new (obj->renderArena())
                    BidiRun(start, nextMidpoint.pos+1, obj, bidi.context, dir));
                return appendRunsForObject(nextMidpoint.pos+1, end, obj, bidi);
            }
        }
        else
           addRun(new (obj->renderArena()) BidiRun(start, end, obj, bidi.context, dir));
    }
}

static void appendRun( BidiState &bidi )
{
    if ( emptyRun ) return;
#if BIDI_DEBUG > 1
    kdDebug(6041) << "appendRun: dir="<<(int)dir<<endl;
#endif

    bool b = adjustEmbedding;
    adjustEmbedding = false;

    int start = bidi.sor.pos;
    RenderObject *obj = bidi.sor.obj;
    while( obj && obj != bidi.eor.obj ) {
        appendRunsForObject(start, obj->length(), obj, bidi);
        start = 0;
        obj = Bidinext( bidi.sor.par, obj, bidi );
    }
    if (obj)
        appendRunsForObject(start, bidi.eor.pos+1, obj, bidi);

    bidi.eor.increment( bidi );
    bidi.sor = bidi.eor;
    dir = QChar::DirON;
    bidi.status.eor = QChar::DirON;
    adjustEmbedding = b;
}

static void embed( QChar::Direction d, BidiState &bidi )
{
#if BIDI_DEBUG > 1
    qDebug("*** embed dir=%d emptyrun=%d", d, emptyRun );
#endif
    bool b = adjustEmbedding ;
    adjustEmbedding = false;
    if ( d == QChar::DirPDF ) {
	BidiContext *c = bidi.context->parent;
	if (c) {
	    if ( bidi.eor != bidi.last ) {
		appendRun( bidi );
		bidi.eor = bidi.last;
	    }
	    appendRun( bidi );
	    emptyRun = true;
	    bidi.status.last = bidi.context->dir;
	    bidi.context->deref();
	    bidi.context = c;
	    if(bidi.context->override)
		dir = bidi.context->dir;
	    else
		dir = QChar::DirON;
	    bidi.status.lastStrong = bidi.context->dir;
	}
    } else {
	QChar::Direction runDir;
	if( d == QChar::DirRLE || d == QChar::DirRLO )
	    runDir = QChar::DirR;
	else
	    runDir = QChar::DirL;
	bool override;
	if( d == QChar::DirLRO || d == QChar::DirRLO )
	    override = true;
	else
	    override = false;

	unsigned char level = bidi.context->level;
	if ( runDir == QChar::DirR ) {
	    if(level%2) // we have an odd level
		level += 2;
	    else
		level++;
	} else {
	    if(level%2) // we have an odd level
		level++;
	    else
		level += 2;
	}

	if(level < 61) {
	    if ( bidi.eor != bidi.last ) {
                appendRun( bidi );
                bidi.eor = bidi.last;
            }
            appendRun( bidi );
            emptyRun = true;

	    bidi.context = new BidiContext(level, runDir, bidi.context, override);
	    bidi.context->ref();
	    dir = runDir;
	    bidi.status.last = runDir;
	    bidi.status.lastStrong = runDir;
	    bidi.status.eor = runDir;
	}
    }
    adjustEmbedding = b;
}

InlineFlowBox* RenderBlock::createLineBoxes(RenderObject* obj)
{
    // See if we have an unconstructed line box for this object that is also
    // the last item on the line.
    KHTMLAssert(obj->isInlineFlow() || obj == this);
    RenderFlow* flow = static_cast<RenderFlow*>(obj);

    // Get the last box we made for this render object.
    InlineFlowBox* box = flow->lastLineBox();

    // If this box is constructed then it is from a previous line, and we need
    // to make a new box for our line.  If this box is unconstructed but it has
    // something following it on the line, then we know we have to make a new box
    // as well.  In this situation our inline has actually been split in two on
    // the same line (this can happen with very fancy language mixtures).
    if (!box || box->isConstructed() || box->nextOnLine()) {
        // We need to make a new box for this render object.  Once
        // made, we need to place it at the end of the current line.
        InlineBox* newBox = obj->createInlineBox(false, obj == this);
        KHTMLAssert(newBox->isInlineFlowBox());
        box = static_cast<InlineFlowBox*>(newBox);
        box->setFirstLineStyleBit(m_firstLine);

        // We have a new box. Append it to the inline box we get by constructing our
        // parent.  If we have hit the block itself, then |box| represents the root
        // inline box for the line, and it doesn't have to be appended to any parent
        // inline.
        if (obj != this) {
            InlineFlowBox* parentBox = createLineBoxes(obj->parent());
            parentBox->addToLine(box);
        }
    }

    return box;
}

InlineFlowBox* RenderBlock::constructLine(const BidiIterator &start, const BidiIterator &end)
{
    if (!sFirstBidiRun)
        return 0; // We had no runs. Don't make a root inline box at all. The line is empty.

    InlineFlowBox* parentBox = 0;
    for (BidiRun* r = sFirstBidiRun; r; r = r->nextRun) {
        // Create a box for our object.
        r->box = r->obj->createInlineBox(r->obj->isPositioned(), false);

        // If we have no parent box yet, or if the run is not simply a sibling,
        // then we need to construct inline boxes as necessary to properly enclose the
        // run's inline box.
        if (!parentBox || (parentBox->object() != r->obj->parent()))
            // Create new inline boxes all the way back to the appropriate insertion point.
            parentBox = createLineBoxes(r->obj->parent());

        // Append the inline box to this line.
        parentBox->addToLine(r->box);
    }

    // We should have a root inline box.  It should be unconstructed and
    // be the last continuation of our line list.
    KHTMLAssert(lastLineBox() && !lastLineBox()->isConstructed());

    // Set bits on our inline flow boxes that indicate which sides should
    // paint borders/margins/padding.  This knowledge will ultimately be used when
    // we determine the horizontal positions and widths of all the inline boxes on
    // the line.
    RenderObject* endObject = 0;
    bool lastLine = !end.obj;
    if (end.obj && end.pos == 0)
        endObject = end.obj;
    lastLineBox()->determineSpacingForFlowBoxes(lastLine, endObject);

    // Now mark the line boxes as being constructed.
    lastLineBox()->setConstructed();

    // Return the last line.
    return lastLineBox();
}

void RenderBlock::computeHorizontalPositionsForLine(InlineFlowBox* lineBox, BidiState &bidi)
{
    // First determine our total width.
    int totWidth = lineBox->getFlowSpacingWidth();
    BidiRun* r = 0;
    for (r = sFirstBidiRun; r; r = r->nextRun) {
        if (r->obj->isPositioned())
            continue; // Positioned objects are only participating to figure out their
                      // correct static x position.  They have no effect on the width.
        if (r->obj->isText())
            r->box->setWidth(static_cast<RenderText *>(r->obj)->width(r->start, r->stop-r->start, m_firstLine));
        else if (!r->obj->isInlineFlow()) {
            r->obj->calcWidth();
            r->box->setWidth(r->obj->width());
            totWidth += r->obj->marginLeft() + r->obj->marginRight();
        }
        totWidth += r->box->width();
    }

    // Armed with the total width of the line (without justification),
    // we now examine our text-align property in order to determine where to position the
    // objects horizontally.  The total width of the line can be increased if we end up
    // justifying text.
    int x = leftOffset(m_height);
    int availableWidth = lineWidth(m_height);
    switch(style()->textAlign()) {
        case LEFT:
        case KHTML_LEFT:
            numSpaces = 0;
            break;
        case JUSTIFY:
            if (numSpaces != 0 && !bidi.current.atEnd() && !bidi.current.obj->isBR() )
                break;
            // fall through
        case TAAUTO:
            numSpaces = 0;
            // for right to left fall through to right aligned
            if (bidi.context->basicDir == QChar::DirL)
                break;
        case RIGHT:
        case KHTML_RIGHT:
            x += availableWidth - totWidth;
            numSpaces = 0;
            break;
        case CENTER:
        case KHTML_CENTER:
            int xd = (availableWidth - totWidth)/2;
            x += xd >0 ? xd : 0;
            numSpaces = 0;