bidi.cpp

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    if (obj && obj->isListMarker())
        return obj->style()->direction() == LTR ? LeftToRight : RightToLeft;

    return OtherNeutral;
}

// -------------------------------------------------------------------------------------------------

static void chopMidpointsAt(RenderObject* obj, unsigned pos)
{
    if (!sNumMidpoints)
        return;
    InlineIterator* midpoints = smidpoints->data();
    for (int i = sNumMidpoints - 1; i >= 0; i--) {
        const InlineIterator& point = midpoints[i];
        if (point.obj == obj && point.pos == pos) {
            sNumMidpoints = i;
            break;
        }
    }
}

static void checkMidpoints(InlineIterator& lBreak)
{
    // 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 doesn't
    // preserve whitespace.
    if (lBreak.obj && sNumMidpoints && sNumMidpoints % 2 == 0) {
        InlineIterator* midpoints = smidpoints->data();
        InlineIterator& endpoint = midpoints[sNumMidpoints-2];
        const InlineIterator& startpoint = midpoints[sNumMidpoints-1];
        InlineIterator currpoint = endpoint;
        while (!currpoint.atEnd() && currpoint != startpoint && currpoint != lBreak)
            currpoint.increment();
        if (currpoint == lBreak) {
            // We hit the line break before the start point.  Shave off the start point.
            sNumMidpoints--;
            if (endpoint.obj->style()->collapseWhiteSpace()) {
                if (endpoint.obj->isText()) {
                    // Don't shave a character off the endpoint if it was from a soft hyphen.
                    RenderText* textObj = toRenderText(endpoint.obj);
                    if (endpoint.pos + 1 < textObj->textLength()) {
                        if (textObj->characters()[endpoint.pos+1] == softHyphen)
                            return;
                    } else if (startpoint.obj->isText()) {
                        RenderText *startText = toRenderText(startpoint.obj);
                        if (startText->textLength() && startText->characters()[0] == softHyphen)
                            return;
                    }
                }
                endpoint.pos--;
            }
        }
    }    
}

static void addMidpoint(const InlineIterator& midpoint)
{
    if (smidpoints->size() <= sNumMidpoints)
        smidpoints->grow(sNumMidpoints + 10);

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

static void appendRunsForObject(int start, int end, RenderObject* obj, InlineBidiResolver& resolver)
{
    if (start > end || obj->isFloating() ||
        (obj->isPositioned() && !obj->style()->hasStaticX() && !obj->style()->hasStaticY() && !obj->container()->isRenderInline()))
        return;

    bool haveNextMidpoint = (sCurrMidpoint < sNumMidpoints);
    InlineIterator 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, resolver);
    } else {
        if (!haveNextMidpoint || (obj != nextMidpoint.obj)) {
            resolver.addRun(new (obj->renderArena()) BidiRun(start, end, obj, resolver.context(), resolver.dir()));
            return;
        }

        // An end midpoint has been encountered within our object.  We
        // need to go ahead and append a run with our endpoint.
        if (static_cast<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.
                if (static_cast<int>(nextMidpoint.pos + 1) > start)
                    resolver.addRun(new (obj->renderArena())
                        BidiRun(start, nextMidpoint.pos + 1, obj, resolver.context(), resolver.dir()));
                return appendRunsForObject(nextMidpoint.pos + 1, end, obj, resolver);
            }
        } else
           resolver.addRun(new (obj->renderArena()) BidiRun(start, end, obj, resolver.context(), resolver.dir()));
    }
}

template <>
void InlineBidiResolver::appendRun()
{
    if (!emptyRun && !eor.atEnd()) {
        int start = sor.pos;
        RenderObject *obj = sor.obj;
        while (obj && obj != eor.obj && obj != endOfLine.obj) {
            appendRunsForObject(start, obj->length(), obj, *this);        
            start = 0;
            obj = bidiNext(sor.block, obj);
        }
        if (obj) {
            unsigned pos = obj == eor.obj ? eor.pos : UINT_MAX;
            if (obj == endOfLine.obj && endOfLine.pos <= pos) {
                reachedEndOfLine = true;
                pos = endOfLine.pos;
            }
            // It's OK to add runs for zero-length RenderObjects, just don't make the run larger than it should be
            int end = obj->length() ? pos+1 : 0;
            appendRunsForObject(start, end, obj, *this);
        }
        
        eor.increment();
        sor = eor;
    }

    m_direction = OtherNeutral;
    m_status.eor = OtherNeutral;
}

static inline InlineBox* createInlineBoxForRenderer(RenderObject* obj, bool isRootLineBox, bool isOnlyRun = false)
{
    if (isRootLineBox)
        return toRenderBlock(obj)->createRootInlineBox();
    
    if (obj->isText()) {
        InlineTextBox* textBox = toRenderText(obj)->createInlineTextBox();
        // We only treat a box as text for a <br> if we are on a line by ourself or in strict mode
        // (Note the use of strict mode.  In "almost strict" mode, we don't treat the box for <br> as text.)
        if (obj->isBR())
            textBox->setIsText(isOnlyRun || obj->document()->inStrictMode());
        return textBox;
    }
    
    if (obj->isBox())
        return toRenderBox(obj)->createInlineBox();
    
    return toRenderInline(obj)->createInlineFlowBox();
}

static inline void dirtyLineBoxesForRenderer(RenderObject* o, bool fullLayout)
{
    if (o->isText()) {
        if (o->prefWidthsDirty() && o->isCounter())
            toRenderText(o)->calcPrefWidths(0); // FIXME: Counters depend on this hack. No clue why. Should be investigated and removed.
        toRenderText(o)->dirtyLineBoxes(fullLayout);
    } else
        toRenderInline(o)->dirtyLineBoxes(fullLayout);
}

InlineFlowBox* RenderBlock::createLineBoxes(RenderObject* obj, bool firstLine)
{
    // See if we have an unconstructed line box for this object that is also
    // the last item on the line.
    unsigned lineDepth = 1;
    InlineFlowBox* childBox = 0;
    InlineFlowBox* parentBox = 0;
    InlineFlowBox* result = 0;
    do {
        ASSERT(obj->isRenderInline() || obj == this);
        
        // Get the last box we made for this render object.
        parentBox = obj->isRenderInline() ? toRenderInline(obj)->lastLineBox() : toRenderBlock(obj)->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).
        bool constructedNewBox = false;
        if (!parentBox || parentBox->isConstructed() || parentBox->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 = createInlineBoxForRenderer(obj, obj == this);
            ASSERT(newBox->isInlineFlowBox());
            parentBox = static_cast<InlineFlowBox*>(newBox);
            parentBox->setFirstLineStyleBit(firstLine);
            constructedNewBox = true;
        }

        if (!result)
            result = parentBox;

        // 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 (childBox)
            parentBox->addToLine(childBox);

        if (!constructedNewBox || obj == this)
            break;

        childBox = parentBox;        

        // If we've exceeded our line depth, then jump straight to the root and skip all the remaining
        // intermediate inline flows.
        obj = (++lineDepth >= cMaxLineDepth) ? this : obj->parent();

    } while (true);

    return result;
}

RootInlineBox* RenderBlock::constructLine(unsigned runCount, BidiRun* firstRun, BidiRun* lastRun, bool firstLine, bool lastLine, RenderObject* endObject)
{
    ASSERT(firstRun);

    InlineFlowBox* parentBox = 0;
    for (BidiRun* r = firstRun; r; r = r->next()) {
        // Create a box for our object.
        bool isOnlyRun = (runCount == 1);
        if (runCount == 2 && !r->m_object->isListMarker())
            isOnlyRun = ((style()->direction() == RTL) ? lastRun : firstRun)->m_object->isListMarker();

        InlineBox* box = createInlineBoxForRenderer(r->m_object, false, isOnlyRun);
        r->m_box = box;

        if (box) {
            // 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->renderer() != r->m_object->parent())
                // Create new inline boxes all the way back to the appropriate insertion point.
                parentBox = createLineBoxes(r->m_object->parent(), firstLine);

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

            bool visuallyOrdered = r->m_object->style()->visuallyOrdered();
            box->setBidiLevel(visuallyOrdered ? 0 : r->level());

            if (box->isInlineTextBox()) {
                InlineTextBox* text = static_cast<InlineTextBox*>(box);
                text->setStart(r->m_start);
                text->setLen(r->m_stop - r->m_start);
                text->m_dirOverride = r->dirOverride(visuallyOrdered);
            }
        }
    }

    // We should have a root inline box.  It should be unconstructed and
    // be the last continuation of our line list.
    ASSERT(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.
    lastLineBox()->determineSpacingForFlowBoxes(lastLine, endObject);

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

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

void RenderBlock::computeHorizontalPositionsForLine(RootInlineBox* lineBox, bool firstLine, BidiRun* firstRun, BidiRun* trailingSpaceRun, bool reachedEnd)
{
    // First determine our total width.
    int availableWidth = lineWidth(height(), firstLine);
    int totWidth = lineBox->getFlowSpacingWidth();
    bool needsWordSpacing = false;
    unsigned numSpaces = 0;
    ETextAlign textAlign = style()->textAlign();

    for (BidiRun* r = firstRun; r; r = r->next()) {
        if (!r->m_box || r->m_object->isPositioned() || r->m_box->isLineBreak())
            continue; // Positioned objects are only participating to figure out their
                      // correct static x position.  They have no effect on the width.
                      // Similarly, line break boxes have no effect on the width.
        if (r->m_object->isText()) {
            RenderText* rt = toRenderText(r->m_object);

            if (textAlign == JUSTIFY && r != trailingSpaceRun) {
                const UChar* characters = rt->characters();
                for (int i = r->m_start; i < r->m_stop; i++) {
                    UChar c = characters[i];
                    if (c == ' ' || c == '\n' || c == '\t')
                        numSpaces++;
                }
            }

            if (int length = rt->textLength()) {
                if (!r->m_start && needsWordSpacing && isSpaceOrNewline(rt->characters()[r->m_start]))
                    totWidth += rt->style(firstLine)->font().wordSpacing();
                needsWordSpacing = !isSpaceOrNewline(rt->characters()[r->m_stop - 1]) && r->m_stop == length;          
            }
            r->m_box->setWidth(rt->width(r->m_start, r->m_stop - r->m_start, totWidth, firstLine));
        } else if (!r->m_object->isRenderInline()) {
            RenderBox* renderBox = toRenderBox(r->m_object);
            renderBox->calcWidth();
            r->m_box->setWidth(renderBox->width());
            totWidth += renderBox->marginLeft() + renderBox->marginRight();
        }

        totWidth += r->m_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(height(), firstLine);