inlineflowbox.cpp

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{
    int maxPositionTop = 0;
    int maxPositionBottom = 0;
    int maxAscent = 0;
    int maxDescent = 0;

    // Figure out if we're in strict mode.  Note that we can't simply use !style()->htmlHacks(),
    // because that would match almost strict mode as well.
    RenderObject* curr = renderer();
    while (curr && !curr->node())
        curr = curr->container();
    bool strictMode = (curr && curr->document()->inStrictMode());
    
    computeLogicalBoxHeights(maxPositionTop, maxPositionBottom, maxAscent, maxDescent, strictMode);

    if (maxAscent + maxDescent < max(maxPositionTop, maxPositionBottom))
        adjustMaxAscentAndDescent(maxAscent, maxDescent, maxPositionTop, maxPositionBottom);

    int maxHeight = maxAscent + maxDescent;
    int topPosition = heightOfBlock;
    int bottomPosition = heightOfBlock;
    int selectionTop = heightOfBlock;
    int selectionBottom = heightOfBlock;
    placeBoxesVertically(heightOfBlock, maxHeight, maxAscent, strictMode, topPosition, bottomPosition, selectionTop, selectionBottom);

    setVerticalOverflowPositions(topPosition, bottomPosition);
    setVerticalSelectionPositions(selectionTop, selectionBottom);
    
    heightOfBlock += maxHeight;
    
    return heightOfBlock;
}

void InlineFlowBox::adjustMaxAscentAndDescent(int& maxAscent, int& maxDescent,
                                              int maxPositionTop, int maxPositionBottom)
{
    for (InlineBox* curr = firstChild(); curr; curr = curr->nextOnLine()) {
        // The computed lineheight needs to be extended for the
        // positioned elements
        if (curr->renderer()->isPositioned())
            continue; // Positioned placeholders don't affect calculations.
        if (curr->y() == PositionTop || curr->y() == PositionBottom) {
            int lineHeight = curr->renderer()->lineHeight(m_firstLine);
            if (curr->y() == PositionTop) {
                if (maxAscent + maxDescent < lineHeight)
                    maxDescent = lineHeight - maxAscent;
            }
            else {
                if (maxAscent + maxDescent < lineHeight)
                    maxAscent = lineHeight - maxDescent;
            }

            if (maxAscent + maxDescent >= max(maxPositionTop, maxPositionBottom))
                break;
        }

        if (curr->isInlineFlowBox())
            static_cast<InlineFlowBox*>(curr)->adjustMaxAscentAndDescent(maxAscent, maxDescent, maxPositionTop, maxPositionBottom);
    }
}

static int verticalPositionForBox(InlineBox* curr, bool firstLine)
{
    if (curr->renderer()->isText())
        return curr->parent()->y();
    if (curr->renderer()->isBox())
        return toRenderBox(curr->renderer())->verticalPosition(firstLine);
    return toRenderInline(curr->renderer())->verticalPositionFromCache(firstLine);
}

void InlineFlowBox::computeLogicalBoxHeights(int& maxPositionTop, int& maxPositionBottom,
                                             int& maxAscent, int& maxDescent, bool strictMode)
{
    if (isRootInlineBox()) {
        // Examine our root box.
        int lineHeight = renderer()->lineHeight(m_firstLine, true);
        int baseline = renderer()->baselinePosition(m_firstLine, true);
        if (hasTextChildren() || strictMode) {
            int ascent = baseline;
            int descent = lineHeight - ascent;
            if (maxAscent < ascent)
                maxAscent = ascent;
            if (maxDescent < descent)
                maxDescent = descent;
        }
    }
    
    for (InlineBox* curr = firstChild(); curr; curr = curr->nextOnLine()) {
        if (curr->renderer()->isPositioned())
            continue; // Positioned placeholders don't affect calculations.
        
        bool isInlineFlow = curr->isInlineFlowBox();

        int lineHeight = curr->renderer()->lineHeight(m_firstLine);
        int baseline = curr->renderer()->baselinePosition(m_firstLine);
        curr->setY(verticalPositionForBox(curr, m_firstLine));
        if (curr->y() == PositionTop) {
            if (maxPositionTop < lineHeight)
                maxPositionTop = lineHeight;
        }
        else if (curr->y() == PositionBottom) {
            if (maxPositionBottom < lineHeight)
                maxPositionBottom = lineHeight;
        }
        else if ((!isInlineFlow || static_cast<InlineFlowBox*>(curr)->hasTextChildren()) || curr->boxModelObject()->hasHorizontalBordersOrPadding() || strictMode) {
            int ascent = baseline - curr->y();
            int descent = lineHeight - ascent;
            if (maxAscent < ascent)
                maxAscent = ascent;
            if (maxDescent < descent)
                maxDescent = descent;
        }

        if (curr->isInlineFlowBox())
            static_cast<InlineFlowBox*>(curr)->computeLogicalBoxHeights(maxPositionTop, maxPositionBottom, maxAscent, maxDescent, strictMode);
    }
}

void InlineFlowBox::placeBoxesVertically(int yPos, int maxHeight, int maxAscent, bool strictMode,
                                         int& topPosition, int& bottomPosition, int& selectionTop, int& selectionBottom)
{
    if (isRootInlineBox())
        setY(yPos + max(0, maxAscent - renderer()->baselinePosition(m_firstLine, true))); // Place our root box.
    
    for (InlineBox* curr = firstChild(); curr; curr = curr->nextOnLine()) {
        if (curr->renderer()->isPositioned())
            continue; // Positioned placeholders don't affect calculations.
        
        // Adjust boxes to use their real box y/height and not the logical height (as dictated by
        // line-height).
        bool isInlineFlow = curr->isInlineFlowBox();
        if (isInlineFlow)
            static_cast<InlineFlowBox*>(curr)->placeBoxesVertically(yPos, maxHeight, maxAscent, strictMode, topPosition, bottomPosition, selectionTop, selectionBottom);

        bool childAffectsTopBottomPos = true;
        if (curr->y() == PositionTop)
            curr->setY(yPos);
        else if (curr->y() == PositionBottom)
            curr->setY(yPos + maxHeight - curr->renderer()->lineHeight(m_firstLine));
        else {
            if ((isInlineFlow && !static_cast<InlineFlowBox*>(curr)->hasTextChildren()) && !curr->boxModelObject()->hasHorizontalBordersOrPadding() && !strictMode)
                childAffectsTopBottomPos = false;
            int posAdjust = maxAscent - curr->renderer()->baselinePosition(m_firstLine);
            if (!childAffectsTopBottomPos)
                posAdjust = max(0, posAdjust);
            curr->setY(curr->y() + yPos + posAdjust);
        }
        
        int newY = curr->y();
        int overflowTop = 0;
        int overflowBottom = 0;
        if (curr->isText() || curr->isInlineFlowBox()) {
            const Font& font = curr->renderer()->style(m_firstLine)->font();
            newY += curr->renderer()->baselinePosition(m_firstLine) - font.ascent();
            for (ShadowData* shadow = curr->renderer()->style()->textShadow(); shadow; shadow = shadow->next) {
                overflowTop = min(overflowTop, shadow->y - shadow->blur);
                overflowBottom = max(overflowBottom, shadow->y + shadow->blur);
            }

            for (ShadowData* boxShadow = curr->renderer()->style(m_firstLine)->boxShadow(); boxShadow; boxShadow = boxShadow->next) {
                overflowTop = min(overflowTop, boxShadow->y - boxShadow->blur);
                overflowBottom = max(overflowBottom, boxShadow->y + boxShadow->blur);
            }

            for (ShadowData* textShadow = curr->renderer()->style(m_firstLine)->textShadow(); textShadow; textShadow = textShadow->next) {
                overflowTop = min(overflowTop, textShadow->y - textShadow->blur);
                overflowBottom = max(overflowBottom, textShadow->y + textShadow->blur);
            }

            if (curr->renderer()->hasReflection()) {
                RenderBox* box = toRenderBox(curr->renderer());
                overflowTop = min(overflowTop, box->reflectionBox().y());
                overflowBottom = max(overflowBottom, box->reflectionBox().bottom());
            }

            if (curr->isInlineFlowBox())
                newY -= curr->boxModelObject()->borderTop() + curr->boxModelObject()->paddingTop();
        } else if (!curr->renderer()->isBR()) {
            RenderBox* box = toRenderBox(curr->renderer());
            newY += box->marginTop();
            overflowTop = box->overflowTop(false);
            overflowBottom = box->overflowHeight(false) - box->height();
        }

        curr->setY(newY);

        if (childAffectsTopBottomPos) {
            selectionTop = min(selectionTop, newY);
            selectionBottom = max(selectionBottom, newY + curr->height());
            topPosition = min(topPosition, newY + overflowTop);
            bottomPosition = max(bottomPosition, newY + curr->height() + overflowBottom);
        }
    }

    if (isRootInlineBox()) {
        const Font& font = renderer()->style(m_firstLine)->font();
        setY(y() + renderer()->baselinePosition(m_firstLine, true) - font.ascent());
        if (hasTextChildren() || strictMode) {
            selectionTop = min(selectionTop, y());
            selectionBottom = max(selectionBottom, y() + height());
        }
    }
}

bool InlineFlowBox::nodeAtPoint(const HitTestRequest& request, HitTestResult& result, int x, int y, int tx, int ty)
{
    // Check children first.
    for (InlineBox* curr = lastChild(); curr; curr = curr->prevOnLine()) {
        if ((curr->renderer()->isText() || !curr->boxModelObject()->hasSelfPaintingLayer()) && curr->nodeAtPoint(request, result, x, y, tx, ty)) {
            renderer()->updateHitTestResult(result, IntPoint(x - tx, y - ty));
            return true;
        }
    }

    // Now check ourselves.
    IntRect rect(tx + m_x, ty + m_y, m_width, height());
    if (visibleToHitTesting() && rect.contains(x, y)) {
        renderer()->updateHitTestResult(result, IntPoint(x - tx, y - ty)); // Don't add in m_x or m_y here, we want coords in the containing block's space.
        return true;
    }
    
    return false;
}

void InlineFlowBox::paint(RenderObject::PaintInfo& paintInfo, int tx, int ty)
{
    int xPos = tx + m_x - renderer()->maximalOutlineSize(paintInfo.phase);
    int w = width() + 2 * renderer()->maximalOutlineSize(paintInfo.phase);
    int shadowLeft = 0;
    int shadowRight = 0;
    for (ShadowData* boxShadow = renderer()->style(m_firstLine)->boxShadow(); boxShadow; boxShadow = boxShadow->next) {
        shadowLeft = min(boxShadow->x - boxShadow->blur, shadowLeft);
        shadowRight = max(boxShadow->x + boxShadow->blur, shadowRight);
    }
    for (ShadowData* textShadow = renderer()->style(m_firstLine)->textShadow(); textShadow; textShadow = textShadow->next) {
        shadowLeft = min(textShadow->x - textShadow->blur, shadowLeft);
        shadowRight = max(textShadow->x + textShadow->blur, shadowRight);
    }
    xPos += shadowLeft;
    w += -shadowLeft + shadowRight;
    bool intersectsDamageRect = xPos < paintInfo.rect.right() && xPos + w > paintInfo.rect.x();

    if (intersectsDamageRect && paintInfo.phase != PaintPhaseChildOutlines) {
        if (paintInfo.phase == PaintPhaseOutline || paintInfo.phase == PaintPhaseSelfOutline) {
            // Add ourselves to the paint info struct's list of inlines that need to paint their
            // outlines.
            if (renderer()->style()->visibility() == VISIBLE && renderer()->hasOutline() && !isRootInlineBox()) {
                RenderInline* inlineFlow = toRenderInline(renderer());
                if ((inlineFlow->continuation() || inlineFlow->isInlineContinuation()) && !boxModelObject()->hasSelfPaintingLayer()) {
                    // Add ourselves to the containing block of the entire continuation so that it can
                    // paint us atomically.
                    RenderBlock* block = renderer()->containingBlock()->containingBlock();
                    block->addContinuationWithOutline(toRenderInline(renderer()->node()->renderer()));
                } else if (!inlineFlow->isInlineContinuation())
                    paintInfo.outlineObjects->add(inlineFlow);
            }
        } else if (paintInfo.phase == PaintPhaseMask) {
            paintMask(paintInfo, tx, ty);
            return;
        } else {
            // 1. Paint our background, border and box-shadow.
            paintBoxDecorations(paintInfo, tx, ty);

            // 2. Paint our underline and overline.
            paintTextDecorations(paintInfo, tx, ty, false);
        }
    }

    if (paintInfo.phase == PaintPhaseMask)
        return;

    PaintPhase paintPhase = paintInfo.phase == PaintPhaseChildOutlines ? PaintPhaseOutline : paintInfo.phase;
    RenderObject::PaintInfo childInfo(paintInfo);
    childInfo.phase = paintPhase;
    childInfo.paintingRoot = renderer()->paintingRootForChildren(paintInfo);
    
    // 3. Paint our children.
    if (paintPhase != PaintPhaseSelfOutline) {
        for (InlineBox* curr = firstChild(); curr; curr = curr->nextOnLine()) {
            if (curr->renderer()->isText() || !curr->boxModelObject()->hasSelfPaintingLayer())
                curr->paint(childInfo, tx, ty);
        }
    }

    // 4. Paint our strike-through
    if (intersectsDamageRect && (paintInfo.phase == PaintPhaseForeground || paintInfo.phase == PaintPhaseSelection))
        paintTextDecorations(paintInfo, tx, ty, true);
}

void InlineFlowBox::paintFillLayers(const RenderObject::PaintInfo& paintInfo, const Color& c, const FillLayer* fillLayer,
                                    int my, int mh, int _tx, int _ty, int w, int h, CompositeOperator op)
{
    if (!fillLayer)
        return;
    paintFillLayers(paintInfo, c, fillLayer->next(), my, mh, _tx, _ty, w, h, op);
    paintFillLayer(paintInfo, c, fillLayer, my, mh, _tx, _ty, w, h, op);
}

void InlineFlowBox::paintFillLayer(const RenderObject::PaintInfo& paintInfo, const Color& c, const FillLayer* fillLayer,
                                   int my, int mh, int tx, int ty, int w, int h, CompositeOperator op)
{
    StyleImage* img = fillLayer->image();
    bool hasFillImage = img && img->canRender(renderer()->style()->effectiveZoom());
    if ((!hasFillImage && !renderer()->style()->hasBorderRadius()) || (!prevLineBox() && !nextLineBox()) || !parent())
        boxModelObject()->paintFillLayerExtended(paintInfo, c, fillLayer, my, mh, tx, ty, w, h, this, op);
    else {
        // We have a fill image that spans multiple lines.
        // We need to adjust _tx and _ty by the width of all previous lines.
        // Think of background painting on inlines as though you had one long line, a single continuous
        // strip.  Even though that strip has been broken up across multiple lines, you still paint it
        // as though you had one single line.  This means each line has to pick up the background where
        // the previous line left off.
        // FIXME: What the heck do we do with RTL here? The math we're using is obviously not right,
        // but it isn't even clear how this should work at all.
        int xOffsetOnLine = 0;
        for (InlineRunBox* curr = prevLineBox(); curr; curr = curr->prevLineBox())
            xOffsetOnLine += curr->width();
        int startX = tx - xOffsetOnLine;
        int totalWidth = xOffsetOnLine;
        for (InlineRunBox* curr = this; curr; curr = curr->nextLineBox())
            totalWidth += curr->width();
        paintInfo.context->save();
        paintInfo.context->clip(IntRect(tx, ty, width(), height()));
        boxModelObject()->paintFillLayerExtended(paintInfo, c, fillLayer, my, mh, startX, ty, totalWidth, h, this, op);
        paintInfo.context->restore();
    }
}

void InlineFlowBox::paintBoxShadow(GraphicsContext* context, RenderStyle* s, int tx, int ty, int w, int h)
{
    if ((!prevLineBox() && !nextLineBox()) || !parent())
        boxModelObject()->paintBoxShadow(context, tx, ty, w, h, s);
    else {
        // FIXME: We can do better here in the multi-line case. We want to push a clip so that the shadow doesn't
        // protrude incorrectly at the edges, and we want to possibly include shadows cast from the previous/following lines
        boxModelObject()->paintBoxShadow(context, tx, ty, w, h, s, includeLeftEdge(), includeRightEdge());
    }
}

void InlineFlowBox::paintBoxDecorations(RenderObject::PaintInfo& paintInfo, int tx, int ty)
{
    if (!renderer()->shouldPaintWithinRoot(paintInfo) || renderer()->style()->visibility() != VISIBLE || paintInfo.phase != PaintPhaseForeground)
        return;

    // Move x/y to our coordinates.
    tx += m_x;