inlineflowbox.cpp

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    ty += m_y;
    
    int w = width();
    int h = height();

    int my = max(ty, paintInfo.rect.y());
    int mh;
    if (ty < paintInfo.rect.y())
        mh = max(0, h - (paintInfo.rect.y() - ty));
    else
        mh = min(paintInfo.rect.height(), h);

    GraphicsContext* context = paintInfo.context;
    
    // You can use p::first-line to specify a background. If so, the root line boxes for
    // a line may actually have to paint a background.
    RenderStyle* styleToUse = renderer()->style(m_firstLine);
    if ((!parent() && m_firstLine && styleToUse != renderer()->style()) || (parent() && renderer()->hasBoxDecorations())) {
        // Shadow comes first and is behind the background and border.
        if (styleToUse->boxShadow())
            paintBoxShadow(context, styleToUse, tx, ty, w, h);

        Color c = styleToUse->backgroundColor();
        paintFillLayers(paintInfo, c, styleToUse->backgroundLayers(), my, mh, tx, ty, w, h);

        // :first-line cannot be used to put borders on a line. Always paint borders with our
        // non-first-line style.
        if (parent() && renderer()->style()->hasBorder()) {
            StyleImage* borderImage = renderer()->style()->borderImage().image();
            bool hasBorderImage = borderImage && borderImage->canRender(styleToUse->effectiveZoom());
            if (hasBorderImage && !borderImage->isLoaded())
                return; // Don't paint anything while we wait for the image to load.

            // The simple case is where we either have no border image or we are the only box for this object.  In those
            // cases only a single call to draw is required.
            if (!hasBorderImage || (!prevLineBox() && !nextLineBox()))
                boxModelObject()->paintBorder(context, tx, ty, w, h, renderer()->style(), includeLeftEdge(), includeRightEdge());
            else {
                // We have a border image that spans multiple lines.
                // We need to adjust _tx and _ty by the width of all previous lines.
                // Think of border image 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 image 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();
                context->save();
                context->clip(IntRect(tx, ty, width(), height()));
                boxModelObject()->paintBorder(context, startX, ty, totalWidth, h, renderer()->style());
                context->restore();
            }
        }
    }
}

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

    // Move x/y to our coordinates.
    tx += m_x;
    ty += m_y;
    
    int w = width();
    int h = height();

    int my = max(ty, paintInfo.rect.y());
    int mh;
    if (ty < paintInfo.rect.y())
        mh = max(0, h - (paintInfo.rect.y() - ty));
    else
        mh = min(paintInfo.rect.height(), h);

    
    // Figure out if we need to push a transparency layer to render our mask.
    bool pushTransparencyLayer = false;
    const NinePieceImage& maskNinePieceImage = renderer()->style()->maskBoxImage();
    StyleImage* maskBoxImage = renderer()->style()->maskBoxImage().image();
    if ((maskBoxImage && renderer()->style()->maskLayers()->hasImage()) || renderer()->style()->maskLayers()->next())
        pushTransparencyLayer = true;
    
    CompositeOperator compositeOp = CompositeDestinationIn;
    if (pushTransparencyLayer) {
        paintInfo.context->setCompositeOperation(CompositeDestinationIn);
        paintInfo.context->beginTransparencyLayer(1.0f);
        compositeOp = CompositeSourceOver;
    }

    paintFillLayers(paintInfo, Color(), renderer()->style()->maskLayers(), my, mh, tx, ty, w, h, compositeOp);
    
    bool hasBoxImage = maskBoxImage && maskBoxImage->canRender(renderer()->style()->effectiveZoom());
    if (!hasBoxImage || !maskBoxImage->isLoaded())
        return; // Don't paint anything while we wait for the image to load.

    // The simple case is where we are the only box for this object.  In those
    // cases only a single call to draw is required.
    if (!prevLineBox() && !nextLineBox()) {
        boxModelObject()->paintNinePieceImage(paintInfo.context, tx, ty, w, h, renderer()->style(), maskNinePieceImage, compositeOp);
    } else {
        // We have a mask image that spans multiple lines.
        // We need to adjust _tx and _ty by the width of all previous lines.
        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()->paintNinePieceImage(paintInfo.context, startX, ty, totalWidth, h, renderer()->style(), maskNinePieceImage, compositeOp);
        paintInfo.context->restore();
    }
    
    if (pushTransparencyLayer)
        paintInfo.context->endTransparencyLayer();
}

static bool shouldDrawTextDecoration(RenderObject* obj)
{
    for (RenderObject* curr = obj->firstChild(); curr; curr = curr->nextSibling()) {
        if (curr->isRenderInline())
            return true;
        if (curr->isText() && !curr->isBR()) {
            if (!curr->style()->collapseWhiteSpace())
                return true;
            Node* currElement = curr->node();
            if (!currElement)
                return true;
            if (!currElement->isTextNode())
                return true;
            if (!static_cast<Text*>(currElement)->containsOnlyWhitespace())
                return true;
        }
    }
    return false;
}

void InlineFlowBox::paintTextDecorations(RenderObject::PaintInfo& paintInfo, int tx, int ty, bool paintedChildren)
{
    // Paint text decorations like underlines/overlines. We only do this if we aren't in quirks mode (i.e., in
    // almost-strict mode or strict mode).
    if (renderer()->style()->htmlHacks() || !renderer()->shouldPaintWithinRoot(paintInfo) ||
        renderer()->style()->visibility() != VISIBLE)
        return;
    
    // We don't want underlines or other decorations when we're trying to draw nothing but the selection as white text.
    if (paintInfo.phase == PaintPhaseSelection && paintInfo.forceBlackText)
        return;

    GraphicsContext* context = paintInfo.context;
    tx += m_x;
    ty += m_y;
    RenderStyle* styleToUse = renderer()->style(m_firstLine);
    int deco = parent() ? styleToUse->textDecoration() : styleToUse->textDecorationsInEffect();
    if (deco != TDNONE && 
        ((!paintedChildren && ((deco & UNDERLINE) || (deco & OVERLINE))) || (paintedChildren && (deco & LINE_THROUGH))) &&
        shouldDrawTextDecoration(renderer())) {
        int x = m_x + borderLeft() + paddingLeft();
        int w = m_width - (borderLeft() + paddingLeft() + borderRight() + paddingRight());
        RootInlineBox* rootLine = root();
        if (rootLine->ellipsisBox()) {
            int ellipsisX = rootLine->ellipsisBox()->x();
            int ellipsisWidth = rootLine->ellipsisBox()->width();
            
            // FIXME: Will need to work with RTL
            if (rootLine == this) {
                if (x + w >= ellipsisX + ellipsisWidth)
                    w -= (x + w - ellipsisX - ellipsisWidth);
            } else {
                if (x >= ellipsisX)
                    return;
                if (x + w >= ellipsisX)
                    w -= (x + w - ellipsisX);
            }
        }

        // We must have child boxes and have decorations defined.
        tx += borderLeft() + paddingLeft();

        Color underline, overline, linethrough;
        underline = overline = linethrough = styleToUse->color();
        if (!parent())
            renderer()->getTextDecorationColors(deco, underline, overline, linethrough);

        bool isPrinting = renderer()->document()->printing();
        context->setStrokeThickness(1.0f); // FIXME: We should improve this rule and not always just assume 1.

        bool paintUnderline = deco & UNDERLINE && !paintedChildren;
        bool paintOverline = deco & OVERLINE && !paintedChildren;
        bool paintLineThrough = deco & LINE_THROUGH && paintedChildren;

        bool linesAreOpaque = !isPrinting && (!paintUnderline || underline.alpha() == 255) && (!paintOverline || overline.alpha() == 255) && (!paintLineThrough || linethrough.alpha() == 255);

        int baselinePos = renderer()->style(m_firstLine)->font().ascent();
        if (!isRootInlineBox())
            baselinePos += borderTop() + paddingTop();

        bool setClip = false;
        int extraOffset = 0;
        ShadowData* shadow = styleToUse->textShadow();
        if (!linesAreOpaque && shadow && shadow->next) {
            IntRect clipRect(tx, ty, w, baselinePos + 2);
            for (ShadowData* s = shadow; s; s = s->next) {
                IntRect shadowRect(tx, ty, w, baselinePos + 2);
                shadowRect.inflate(s->blur);
                shadowRect.move(s->x, s->y);
                clipRect.unite(shadowRect);
                extraOffset = max(extraOffset, max(0, s->y) + s->blur);
            }
            context->save();
            context->clip(clipRect);
            extraOffset += baselinePos + 2;
            ty += extraOffset;
            setClip = true;
        }

        bool setShadow = false;
        do {
            if (shadow) {
                if (!shadow->next) {
                    // The last set of lines paints normally inside the clip.
                    ty -= extraOffset;
                    extraOffset = 0;
                }
                context->setShadow(IntSize(shadow->x, shadow->y - extraOffset), shadow->blur, shadow->color);
                setShadow = true;
                shadow = shadow->next;
            }

            if (paintUnderline) {
                context->setStrokeColor(underline);
                context->setStrokeStyle(SolidStroke);
                // Leave one pixel of white between the baseline and the underline.
                context->drawLineForText(IntPoint(tx, ty + baselinePos + 1), w, isPrinting);
            }
            if (paintOverline) {
                context->setStrokeColor(overline);
                context->setStrokeStyle(SolidStroke);
                context->drawLineForText(IntPoint(tx, ty), w, isPrinting);
            }
            if (paintLineThrough) {
                context->setStrokeColor(linethrough);
                context->setStrokeStyle(SolidStroke);
                context->drawLineForText(IntPoint(tx, ty + 2 * baselinePos / 3), w, isPrinting);
            }
        } while (shadow);

        if (setClip)
            context->restore();
        else if (setShadow)
            context->clearShadow();
    }
}

InlineBox* InlineFlowBox::firstLeafChild()
{
    return firstLeafChildAfterBox();
}

InlineBox* InlineFlowBox::lastLeafChild()
{
    return lastLeafChildBeforeBox();
}

InlineBox* InlineFlowBox::firstLeafChildAfterBox(InlineBox* start)
{
    InlineBox* leaf = 0;
    for (InlineBox* box = start ? start->nextOnLine() : firstChild(); box && !leaf; box = box->nextOnLine())
        leaf = box->firstLeafChild();
    if (start && !leaf && parent())
        return parent()->firstLeafChildAfterBox(this);
    return leaf;
}

InlineBox* InlineFlowBox::lastLeafChildBeforeBox(InlineBox* start)
{
    InlineBox* leaf = 0;
    for (InlineBox* box = start ? start->prevOnLine() : lastChild(); box && !leaf; box = box->prevOnLine())
        leaf = box->lastLeafChild();
    if (start && !leaf && parent())
        return parent()->lastLeafChildBeforeBox(this);
    return leaf;
}

RenderObject::SelectionState InlineFlowBox::selectionState()
{
    return RenderObject::SelectionNone;
}

bool InlineFlowBox::canAccommodateEllipsis(bool ltr, int blockEdge, int ellipsisWidth)
{
    for (InlineBox *box = firstChild(); box; box = box->nextOnLine()) {
        if (!box->canAccommodateEllipsis(ltr, blockEdge, ellipsisWidth))
            return false;
    }
    return true;
}

int InlineFlowBox::placeEllipsisBox(bool ltr, int blockEdge, int ellipsisWidth, bool& foundBox)
{
    int result = -1;
    for (InlineBox *box = firstChild(); box; box = box->nextOnLine()) {
        int currResult = box->placeEllipsisBox(ltr, blockEdge, ellipsisWidth, foundBox);
        if (currResult != -1 && result == -1)
            result = currResult;
    }
    return result;
}

void InlineFlowBox::clearTruncation()
{
    for (InlineBox *box = firstChild(); box; box = box->nextOnLine())
        box->clearTruncation();
}

#ifndef NDEBUG

void InlineFlowBox::checkConsistency() const
{
#ifdef CHECK_CONSISTENCY
    ASSERT(!m_hasBadChildList);
    const InlineBox* prev = 0;
    for (const InlineBox* child = m_firstChild; child; child = child->nextOnLine()) {
        ASSERT(child->parent() == this);
        ASSERT(child->prevOnLine() == prev);
        prev = child;
    }
    ASSERT(prev == m_lastChild);
#endif
}

#endif

} // namespace WebCore