C++ RenderStyle类代码示例

PassRefPtr<CSSValue> CSSComputedStyleDeclaration::getSVGPropertyCSSValue(int propertyID, EUpdateLayout updateLayout) const
{
    Node* node = m_node.get();
    if (!node)
        return 0;
    
    // Make sure our layout is up to date before we allow a query on these attributes.
    if (updateLayout)
        node->document()->updateLayout();
        
    RenderStyle* style = node->computedStyle();
    if (!style)
        return 0;
    
    const SVGRenderStyle* svgStyle = style->svgStyle();
    if (!svgStyle)
        return 0;
    
    switch (static_cast<CSSPropertyID>(propertyID)) {
        case CSSPropertyClipRule:
            return CSSPrimitiveValue::create(svgStyle->clipRule());
        case CSSPropertyFloodOpacity:
            return CSSPrimitiveValue::create(svgStyle->floodOpacity(), CSSPrimitiveValue::CSS_NUMBER);
        case CSSPropertyStopOpacity:
            return CSSPrimitiveValue::create(svgStyle->stopOpacity(), CSSPrimitiveValue::CSS_NUMBER);
        case CSSPropertyColorInterpolation:
            return CSSPrimitiveValue::create(svgStyle->colorInterpolation());
        case CSSPropertyColorInterpolationFilters:
            return CSSPrimitiveValue::create(svgStyle->colorInterpolationFilters());
        case CSSPropertyFillOpacity:
            return CSSPrimitiveValue::create(svgStyle->fillOpacity(), CSSPrimitiveValue::CSS_NUMBER);
        case CSSPropertyFillRule:
            return CSSPrimitiveValue::create(svgStyle->fillRule());
        case CSSPropertyColorRendering:
            return CSSPrimitiveValue::create(svgStyle->colorRendering());
        case CSSPropertyImageRendering:
            return CSSPrimitiveValue::create(svgStyle->imageRendering());
        case CSSPropertyShapeRendering:
            return CSSPrimitiveValue::create(svgStyle->shapeRendering());
        case CSSPropertyStrokeLinecap:
            return CSSPrimitiveValue::create(svgStyle->capStyle());
        case CSSPropertyStrokeLinejoin:
            return CSSPrimitiveValue::create(svgStyle->joinStyle());
        case CSSPropertyStrokeMiterlimit:
            return CSSPrimitiveValue::create(svgStyle->strokeMiterLimit(), CSSPrimitiveValue::CSS_NUMBER);
        case CSSPropertyStrokeOpacity:
            return CSSPrimitiveValue::create(svgStyle->strokeOpacity(), CSSPrimitiveValue::CSS_NUMBER);
        case CSSPropertyAlignmentBaseline:
            return CSSPrimitiveValue::create(svgStyle->alignmentBaseline());
        case CSSPropertyDominantBaseline:
            return CSSPrimitiveValue::create(svgStyle->dominantBaseline());
        case CSSPropertyTextAnchor:
            return CSSPrimitiveValue::create(svgStyle->textAnchor());
        case CSSPropertyWritingMode:
            return CSSPrimitiveValue::create(svgStyle->writingMode());
        case CSSPropertyClipPath:
            if (!svgStyle->clipperResource().isEmpty())
                return CSSPrimitiveValue::create(svgStyle->clipperResource(), CSSPrimitiveValue::CSS_URI);
            return CSSPrimitiveValue::createIdentifier(CSSValueNone);
        case CSSPropertyMask:
            if (!svgStyle->maskerResource().isEmpty())
                return CSSPrimitiveValue::create(svgStyle->maskerResource(), CSSPrimitiveValue::CSS_URI);
            return CSSPrimitiveValue::createIdentifier(CSSValueNone);
        case CSSPropertyFilter:
            if (!svgStyle->filterResource().isEmpty())
                return CSSPrimitiveValue::create(svgStyle->filterResource(), CSSPrimitiveValue::CSS_URI);
            return CSSPrimitiveValue::createIdentifier(CSSValueNone);
        case CSSPropertyFloodColor:
            return CSSPrimitiveValue::createColor(svgStyle->floodColor().rgb());
        case CSSPropertyLightingColor:
            return CSSPrimitiveValue::createColor(svgStyle->lightingColor().rgb());
        case CSSPropertyStopColor:
            return CSSPrimitiveValue::createColor(svgStyle->stopColor().rgb());
        case CSSPropertyFill:
            return svgStyle->fillPaint();
        case CSSPropertyKerning:
            return SVGLength::toCSSPrimitiveValue(svgStyle->kerning());
        case CSSPropertyMarkerEnd:
            if (!svgStyle->markerEndResource().isEmpty())
                return CSSPrimitiveValue::create(svgStyle->markerEndResource(), CSSPrimitiveValue::CSS_URI);
            return CSSPrimitiveValue::createIdentifier(CSSValueNone);
        case CSSPropertyMarkerMid:
            if (!svgStyle->markerMidResource().isEmpty())
                return CSSPrimitiveValue::create(svgStyle->markerMidResource(), CSSPrimitiveValue::CSS_URI);
            return CSSPrimitiveValue::createIdentifier(CSSValueNone);
        case CSSPropertyMarkerStart:
            if (!svgStyle->markerStartResource().isEmpty())
                return CSSPrimitiveValue::create(svgStyle->markerStartResource(), CSSPrimitiveValue::CSS_URI);
            return CSSPrimitiveValue::createIdentifier(CSSValueNone);
        case CSSPropertyStroke:
            return svgStyle->strokePaint();
        case CSSPropertyStrokeDasharray:
            return strokeDashArrayToCSSValueList(svgStyle->strokeDashArray());
        case CSSPropertyStrokeDashoffset:
            return SVGLength::toCSSPrimitiveValue(svgStyle->strokeDashOffset());
        case CSSPropertyStrokeWidth:
            return SVGLength::toCSSPrimitiveValue(svgStyle->strokeWidth());
        case CSSPropertyBaselineShift: {
            switch (svgStyle->baselineShift()) {
                case BS_BASELINE:
//.........这里部分代码省略.........

void RenderObjectChildList::updateBeforeAfterContent(RenderObject* owner, PseudoId type, const RenderObject* styledObject)
{
    // Double check that the document did in fact use generated content rules.  Otherwise we should not have been called.
    ASSERT(owner->document()->styleSheetCollection()->usesBeforeAfterRules());

    // In CSS2, before/after pseudo-content cannot nest.  Check this first.
    if (owner->style()->styleType() == BEFORE || owner->style()->styleType() == AFTER)
        return;
    if (!s_enableUpdateBeforeAfterContent)
        return;
    
    if (!styledObject)
        styledObject = owner;

    RenderStyle* pseudoElementStyle = styledObject->getCachedPseudoStyle(type);
    RenderObject* child;
    switch (type) {
    case BEFORE:
        child = beforePseudoElementRenderer(owner);
        break;
    case AFTER:
        child = afterPseudoElementRenderer(owner);
        break;
    default:
        ASSERT_NOT_REACHED();
        return;
    }

    // Whether or not we currently have generated content attached.
    bool oldContentPresent = child;

    // Whether or not we now want generated content.
    bool newContentWanted = pseudoElementStyle && pseudoElementStyle->display() != NONE;

    // For <q><p/></q>, if this object is the inline continuation of the <q>, we only want to generate
    // :after content and not :before content.
    if (newContentWanted && type == BEFORE && owner->isElementContinuation())
        newContentWanted = false;

    // Similarly, if we're the beginning of a <q>, and there's an inline continuation for our object,
    // then we don't generate the :after content.
    if (newContentWanted && type == AFTER && owner->virtualContinuation())
        newContentWanted = false;
    
    // If we don't want generated content any longer, or if we have generated content, but it's no longer
    // identical to the new content data we want to build render objects for, then we nuke all
    // of the old generated content.
    if (oldContentPresent && (!newContentWanted || Node::diff(child->style(), pseudoElementStyle, owner->document()) == Node::Detach)) {
        // Nuke the child. 
        if (child->style()->styleType() == type) {
            oldContentPresent = false;
            child->destroy();
            child = (type == BEFORE) ? owner->virtualChildren()->firstChild() : owner->virtualChildren()->lastChild();
        }
    }

    // If we have no pseudo-element style or if the pseudo-element style's display type is NONE, then we
    // have no generated content and can now return.
    if (!newContentWanted)
        return;

    if (owner->isRenderInline() && !pseudoElementStyle->isDisplayInlineType() && !pseudoElementStyle->isFloating() &&
        !pseudoElementStyle->hasOutOfFlowPosition())
        // According to the CSS2 spec (the end of section 12.1), the only allowed
        // display values for the pseudo style are NONE and INLINE for inline flows.
        // FIXME: CSS2.1 lifted this restriction, but block display types will crash.
        // For now we at least relax the restriction to allow all inline types like inline-block
        // and inline-table.
        pseudoElementStyle->setDisplay(INLINE);

    if (oldContentPresent) {
        updateBeforeAfterStyle(child, type, pseudoElementStyle);
        return; // We've updated the generated content. That's all we needed to do.
    }
    
    RenderObject* insertBefore = (type == BEFORE) ? owner->virtualChildren()->firstChild() : 0;
    if (insertBefore && insertBefore->isAnonymousBlock() && insertBefore->childrenInline() && !insertBefore->isEmpty()) {
        // We are going to add the "before" element. We have to check whether the "insertBefore" element
        // is an anonymous block with inline children. If it is, then we should insert the "before" element
        // before the first inline child of the anonymous block, otherwise we will end up with the "before"
        // element in a different block. We do this only when the anonymous block has children, otherwise
        // we end up with the before element in a wrong block.
        insertBefore = insertBefore->firstChild();
    }

    // Nothing goes before the intruded run-in, not even generated content.
    if (insertBefore && insertBefore->isRunIn() && owner->isRenderBlock()
        && toRenderBlock(owner)->runInIsPlacedIntoSiblingBlock(insertBefore))
        insertBefore = insertBefore->nextSibling();

    // Generated content consists of a single container that houses multiple children (specified
    // by the content property). This generated content container gets the pseudo-element style set on it.
    // For pseudo-elements that are regions, the container is the RenderRegion.
    RenderObject* generatedContentContainer = 0;

    if (!pseudoElementStyle->regionThread().isEmpty())
        generatedContentContainer = ensureBeforeAfterContainer(owner, type, pseudoElementStyle, styledObject->node(), insertBefore);
    else {
        // Walk our list of generated content and create render objects for each.
        for (const ContentData* content = pseudoElementStyle->contentData(); content; content = content->next()) {
//.........这里部分代码省略.........

void RenderMenuList::adjustInnerStyle()
{
    RenderStyle* innerStyle = m_innerBlock->style();
    innerStyle->setFlexGrow(1);
    innerStyle->setFlexShrink(1);
    // min-width: 0; is needed for correct shrinking.
    // FIXME: Remove this line when https://bugs.webkit.org/show_bug.cgi?id=111790 is fixed.
    innerStyle->setMinWidth(Length(0, Fixed));
    // Use margin:auto instead of align-items:center to get safe centering, i.e.
    // when the content overflows, treat it the same as align-items: flex-start.
    // But we only do that for the cases where html.css would otherwise use center.
    if (style()->alignItems() == AlignCenter) {
        innerStyle->setMarginTop(Length());
        innerStyle->setMarginBottom(Length());
        innerStyle->setAlignSelf(AlignFlexStart);
    }

    innerStyle->setPaddingLeft(Length(theme()->popupInternalPaddingLeft(style()), Fixed));
    innerStyle->setPaddingRight(Length(theme()->popupInternalPaddingRight(style()), Fixed));
    innerStyle->setPaddingTop(Length(theme()->popupInternalPaddingTop(style()), Fixed));
    innerStyle->setPaddingBottom(Length(theme()->popupInternalPaddingBottom(style()), Fixed));

    if (m_optionStyle) {
        if ((m_optionStyle->direction() != innerStyle->direction() || m_optionStyle->unicodeBidi() != innerStyle->unicodeBidi()))
            m_innerBlock->setNeedsLayoutAndPrefWidthsRecalc();
        innerStyle->setTextAlign(style()->isLeftToRightDirection() ? LEFT : RIGHT);
        innerStyle->setDirection(m_optionStyle->direction());
        innerStyle->setUnicodeBidi(m_optionStyle->unicodeBidi());
    }
}

PassRefPtrWillBeRawPtr<AnimatableValue> CSSAnimatableValueFactory::createFromColor(CSSPropertyID property, const RenderStyle& style)
{
    Color color = style.colorIncludingFallback(property, false);
    Color visitedLinkColor = style.colorIncludingFallback(property, true);
    return AnimatableColor::create(color, visitedLinkColor);
}

void SVGInlineTextBox::paint(PaintInfo& paintInfo, const LayoutPoint&, LayoutUnit, LayoutUnit)
{
    ASSERT(paintInfo.shouldPaintWithinRoot(renderer()));
    ASSERT(paintInfo.phase == PaintPhaseForeground || paintInfo.phase == PaintPhaseSelection);
    ASSERT(truncation() == cNoTruncation);

    if (renderer()->style()->visibility() != VISIBLE)
        return;

    // Note: We're explicitely not supporting composition & custom underlines and custom highlighters - unlike InlineTextBox.
    // If we ever need that for SVG, it's very easy to refactor and reuse the code.

    RenderObject* parentRenderer = parent()->renderer();
    ASSERT(parentRenderer);

    bool paintSelectedTextOnly = paintInfo.phase == PaintPhaseSelection;
    bool hasSelection = !parentRenderer->document().printing() && selectionState() != RenderObject::SelectionNone;
    if (!hasSelection && paintSelectedTextOnly)
        return;

    RenderSVGInlineText* textRenderer = toRenderSVGInlineText(this->textRenderer());
    ASSERT(textRenderer);
    if (!textShouldBePainted(textRenderer))
        return;

    RenderStyle* style = parentRenderer->style();
    ASSERT(style);

    const SVGRenderStyle* svgStyle = style->svgStyle();
    ASSERT(svgStyle);

    bool hasFill = svgStyle->hasFill();
    bool hasVisibleStroke = svgStyle->hasVisibleStroke();

    RenderStyle* selectionStyle = style;
    if (hasSelection) {
        selectionStyle = parentRenderer->getCachedPseudoStyle(SELECTION);
        if (selectionStyle) {
            const SVGRenderStyle* svgSelectionStyle = selectionStyle->svgStyle();
            ASSERT(svgSelectionStyle);

            if (!hasFill)
                hasFill = svgSelectionStyle->hasFill();
            if (!hasVisibleStroke)
                hasVisibleStroke = svgSelectionStyle->hasVisibleStroke();
        } else
            selectionStyle = style;
    }

    if (textRenderer->frame() && textRenderer->frame()->view() && textRenderer->frame()->view()->paintBehavior() & PaintBehaviorRenderingSVGMask) {
        hasFill = true;
        hasVisibleStroke = false;
    }

    AffineTransform fragmentTransform;
    unsigned textFragmentsSize = m_textFragments.size();
    for (unsigned i = 0; i < textFragmentsSize; ++i) {
        SVGTextFragment& fragment = m_textFragments.at(i);
        ASSERT(!m_paintingResource);

        GraphicsContextStateSaver stateSaver(*paintInfo.context);
        fragment.buildFragmentTransform(fragmentTransform);
        if (!fragmentTransform.isIdentity())
            paintInfo.context->concatCTM(fragmentTransform);

        // Spec: All text decorations except line-through should be drawn before the text is filled and stroked; thus, the text is rendered on top of these decorations.
        int decorations = style->textDecorationsInEffect();
        if (decorations & TextDecorationUnderline)
            paintDecoration(paintInfo.context, TextDecorationUnderline, fragment);
        if (decorations & TextDecorationOverline)
            paintDecoration(paintInfo.context, TextDecorationOverline, fragment);

        for (int i = 0; i < 3; i++) {
            switch (svgStyle->paintOrderType(i)) {
            case PT_FILL:
                // Fill text
                if (hasFill) {
                    m_paintingResourceMode = ApplyToFillMode | ApplyToTextMode;
                    paintText(paintInfo.context, style, selectionStyle, fragment, hasSelection, paintSelectedTextOnly);
                }
                break;
            case PT_STROKE:
                // Stroke text
                if (hasVisibleStroke) {
                    m_paintingResourceMode = ApplyToStrokeMode | ApplyToTextMode;
                    paintText(paintInfo.context, style, selectionStyle, fragment, hasSelection, paintSelectedTextOnly);
                }
                break;
            case PT_MARKERS:
                // Markers don't apply to text
                break;
            default:
                ASSERT_NOT_REACHED();
                break;
            }
        }

        // Spec: Line-through should be drawn after the text is filled and stroked; thus, the line-through is rendered on top of the text.
        if (decorations & TextDecorationLineThrough)
            paintDecoration(paintInfo.context, TextDecorationLineThrough, fragment);
//.........这里部分代码省略.........

bool CSSPropertyEquality::propertiesEqual(CSSPropertyID prop, const RenderStyle& a, const RenderStyle& b)
{
    switch (prop) {
    case CSSPropertyBackgroundColor:
        return a.backgroundColor().resolve(a.color()) == b.backgroundColor().resolve(b.color())
            && a.visitedLinkBackgroundColor().resolve(a.color()) == b.visitedLinkBackgroundColor().resolve(b.color());
    case CSSPropertyBackgroundImage:
        return fillLayersEqual<CSSPropertyBackgroundImage>(a.backgroundLayers(), b.backgroundLayers());
    case CSSPropertyBackgroundPositionX:
        return fillLayersEqual<CSSPropertyBackgroundPositionX>(a.backgroundLayers(), b.backgroundLayers());
    case CSSPropertyBackgroundPositionY:
        return fillLayersEqual<CSSPropertyBackgroundPositionY>(a.backgroundLayers(), b.backgroundLayers());
    case CSSPropertyBackgroundSize:
        return fillLayersEqual<CSSPropertyBackgroundSize>(a.backgroundLayers(), b.backgroundLayers());
    case CSSPropertyBaselineShift:
        return dataEquivalent(a.baselineShiftValue(), b.baselineShiftValue());
    case CSSPropertyBorderBottomColor:
        return a.borderBottomColor().resolve(a.color()) == b.borderBottomColor().resolve(b.color())
            && a.visitedLinkBorderBottomColor().resolve(a.color()) == b.visitedLinkBorderBottomColor().resolve(b.color());
    case CSSPropertyBorderBottomLeftRadius:
        return a.borderBottomLeftRadius() == b.borderBottomLeftRadius();
    case CSSPropertyBorderBottomRightRadius:
        return a.borderBottomRightRadius() == b.borderBottomRightRadius();
    case CSSPropertyBorderBottomWidth:
        return a.borderBottomWidth() == b.borderBottomWidth();
    case CSSPropertyBorderImageOutset:
        return a.borderImageOutset() == b.borderImageOutset();
    case CSSPropertyBorderImageSlice:
        return a.borderImageSlices() == b.borderImageSlices();
    case CSSPropertyBorderImageSource:
        return dataEquivalent(a.borderImageSource(), b.borderImageSource());
    case CSSPropertyBorderImageWidth:
        return a.borderImageWidth() == b.borderImageWidth();
    case CSSPropertyBorderLeftColor:
        return a.borderLeftColor().resolve(a.color()) == b.borderLeftColor().resolve(b.color())
            && a.visitedLinkBorderLeftColor().resolve(a.color()) == b.visitedLinkBorderLeftColor().resolve(b.color());
    case CSSPropertyBorderLeftWidth:
        return a.borderLeftWidth() == b.borderLeftWidth();
    case CSSPropertyBorderRightColor:
        return a.borderRightColor().resolve(a.color()) == b.borderRightColor().resolve(b.color())
            && a.visitedLinkBorderRightColor().resolve(a.color()) == b.visitedLinkBorderRightColor().resolve(b.color());
    case CSSPropertyBorderRightWidth:
        return a.borderRightWidth() == b.borderRightWidth();
    case CSSPropertyBorderTopColor:
        return a.borderTopColor().resolve(a.color()) == b.borderTopColor().resolve(b.color())
            && a.visitedLinkBorderTopColor().resolve(a.color()) == b.visitedLinkBorderTopColor().resolve(b.color());
    case CSSPropertyBorderTopLeftRadius:
        return a.borderTopLeftRadius() == b.borderTopLeftRadius();
    case CSSPropertyBorderTopRightRadius:
        return a.borderTopRightRadius() == b.borderTopRightRadius();
    case CSSPropertyBorderTopWidth:
        return a.borderTopWidth() == b.borderTopWidth();
    case CSSPropertyBottom:
        return a.bottom() == b.bottom();
    case CSSPropertyBoxShadow:
        return dataEquivalent(a.boxShadow(), b.boxShadow());
    case CSSPropertyClip:
        return a.clip() == b.clip();
    case CSSPropertyColor:
        return a.color() == b.color() && a.visitedLinkColor() == b.visitedLinkColor();
    case CSSPropertyFill: {
        const SVGRenderStyle& aSVG = *a.svgStyle();
        const SVGRenderStyle& bSVG = *b.svgStyle();
        return aSVG.fillPaintType() == bSVG.fillPaintType()
            && (aSVG.fillPaintType() != SVGPaint::SVG_PAINTTYPE_RGBCOLOR || aSVG.fillPaintColor() == bSVG.fillPaintColor())
            && aSVG.visitedLinkFillPaintType() == bSVG.visitedLinkFillPaintType()
            && (aSVG.visitedLinkFillPaintType() != SVGPaint::SVG_PAINTTYPE_RGBCOLOR || aSVG.visitedLinkFillPaintColor() == bSVG.visitedLinkFillPaintColor());
    }
    case CSSPropertyFillOpacity:
        return a.fillOpacity() == b.fillOpacity();
    case CSSPropertyFlexBasis:
        return a.flexBasis() == b.flexBasis();
    case CSSPropertyFlexGrow:
        return a.flexGrow() == b.flexGrow();
    case CSSPropertyFlexShrink:
        return a.flexShrink() == b.flexShrink();
    case CSSPropertyFloodColor:
        return a.floodColor() == b.floodColor();
    case CSSPropertyFloodOpacity:
        return a.floodOpacity() == b.floodOpacity();
    case CSSPropertyFontSize:
        // CSSPropertyFontSize: Must pass a specified size to setFontSize if Text Autosizing is enabled, but a computed size
        // if text zoom is enabled (if neither is enabled it's irrelevant as they're probably the same).
        // FIXME: Should we introduce an option to pass the computed font size here, allowing consumers to
        // enable text zoom rather than Text Autosizing? See http://crbug.com/227545.
        return a.specifiedFontSize() == b.specifiedFontSize();
    case CSSPropertyFontWeight:
        return a.fontWeight() == b.fontWeight();
    case CSSPropertyHeight:
        return a.height() == b.height();
    case CSSPropertyLeft:
        return a.left() == b.left();
    case CSSPropertyLetterSpacing:
        return a.letterSpacing() == b.letterSpacing();
    case CSSPropertyLightingColor:
        return a.lightingColor() == b.lightingColor();
    case CSSPropertyLineHeight:
        return a.specifiedLineHeight() == b.specifiedLineHeight();
    case CSSPropertyListStyleImage:
        return dataEquivalent(a.listStyleImage(), b.listStyleImage());
//.........这里部分代码省略.........

bool SVGPaintServerPattern::setup(GraphicsContext*& context, const RenderObject* object, SVGPaintTargetType type, bool isPaintingText) const
{
    CGContextRef contextRef = context->platformContext();

    // Build pattern tile, passing destination object bounding box
    FloatRect targetRect;
    if (isPaintingText) {
        IntRect textBoundary = const_cast<RenderObject*>(object)->absoluteBoundingBoxRect();
        targetRect = object->absoluteTransform().inverse().mapRect(textBoundary);
    } else
        targetRect = CGContextGetPathBoundingBox(contextRef);

    m_ownerElement->buildPattern(targetRect);

    if (!tile())
        return false;

    CGSize cellSize = CGSize(tile()->size());
    CGFloat alpha = 1; // canvasStyle->opacity(); //which?

    context->save();

    // Repesct local pattern transformations
    CGContextConcatCTM(contextRef, patternTransform());

    // Pattern space seems to start in the lower-left, so we flip the Y here. 
    CGSize phase = CGSizeMake(patternBoundaries().x(), -patternBoundaries().y());
    CGContextSetPatternPhase(contextRef, phase);

    RenderStyle* style = object->style();
    CGContextSetAlpha(contextRef, style->opacity()); // or do I set the alpha above?

    ASSERT(!m_pattern);
    CGPatternCallbacks callbacks = {0, patternCallback, NULL};
    m_pattern = CGPatternCreate(tile(),
                                CGRectMake(0, 0, cellSize.width, cellSize.height),
                                CGContextGetCTM(contextRef),
                                patternBoundaries().width(),
                                patternBoundaries().height(),
                                kCGPatternTilingConstantSpacing, // FIXME: should ask CG guys.
                                true, // has color
                                &callbacks);

    if (!m_patternSpace)
        m_patternSpace = CGColorSpaceCreatePattern(0);

    if ((type & ApplyToFillTargetType) && style->svgStyle()->hasFill()) {
        CGContextSetFillColorSpace(contextRef, m_patternSpace);
        CGContextSetFillPattern(contextRef, m_pattern, &alpha);
 
        if (isPaintingText) 
            context->setTextDrawingMode(cTextFill);
    }

    if ((type & ApplyToStrokeTargetType) && style->svgStyle()->hasStroke()) {
        CGContextSetStrokeColorSpace(contextRef, m_patternSpace);
        CGContextSetStrokePattern(contextRef, m_pattern, &alpha);
        applyStrokeStyleToContext(contextRef, style, object);

        if (isPaintingText) 
            context->setTextDrawingMode(cTextStroke);
    }

    return true;
}

IntRect EllipsisBox::selectionRect()
{
    RenderStyle* style = renderer().style(isFirstLineStyle());
    const Font& font = style->font();
    return enclosingIntRect(font.selectionRectForText(RenderBlockFlow::constructTextRun(&renderer(), font, m_str, style, TextRun::AllowTrailingExpansion), IntPoint(logicalLeft(), logicalTop() + root().selectionTopAdjustedForPrecedingBlock()), root().selectionHeightAdjustedForPrecedingBlock()));
}

static void registerElementForFlowThreadIfNeeded(Element& element, const RenderStyle& style)
{
    if (!element.shouldMoveToFlowThread(style))
        return;
    FlowThreadController& flowThreadController = element.document().renderView()->flowThreadController();
    flowThreadController.registerNamedFlowContentElement(element, flowThreadController.ensureRenderFlowThreadWithName(style.flowThread()));
}

bool RenderSVGResourceClipper::pathOnlyClipping(GraphicsContext* context, const AffineTransform& animatedLocalTransform, const FloatRect& objectBoundingBox)
{
    // If the current clip-path gets clipped itself, we have to fallback to masking.
    if (!style()->svgStyle()->clipperResource().isEmpty())
        return false;
    WindRule clipRule = RULE_NONZERO;
    Path clipPath = Path();

    for (Node* childNode = node()->firstChild(); childNode; childNode = childNode->nextSibling()) {
        RenderObject* renderer = childNode->renderer();
        if (!renderer)
            continue;
        // Only shapes or paths are supported for direct clipping. We need to fallback to masking for texts.
        if (renderer->isSVGText())
            return false;
        if (!childNode->isSVGElement() || !toSVGElement(childNode)->isSVGGraphicsElement())
            continue;
        SVGGraphicsElement* styled = toSVGGraphicsElement(childNode);
        RenderStyle* style = renderer->style();
        if (!style || style->display() == NONE || style->visibility() != VISIBLE)
             continue;
        const SVGRenderStyle* svgStyle = style->svgStyle();
        // Current shape in clip-path gets clipped too. Fallback to masking.
        if (!svgStyle->clipperResource().isEmpty())
            return false;

        if (clipPath.isEmpty()) {
            // First clip shape.
            styled->toClipPath(clipPath);
            clipRule = svgStyle->clipRule();
            clipPath.setWindRule(clipRule);
            continue;
        }

        if (RuntimeEnabledFeatures::pathOpsSVGClippingEnabled()) {
            // Attempt to generate a combined clip path, fall back to masking if not possible.
            Path subPath;
            styled->toClipPath(subPath);
            subPath.setWindRule(svgStyle->clipRule());
            if (!clipPath.unionPath(subPath))
                return false;
        } else {
            return false;
        }
    }
    // Only one visible shape/path was found. Directly continue clipping and transform the content to userspace if necessary.
    if (static_cast<SVGClipPathElement*>(node())->clipPathUnitsCurrentValue() == SVGUnitTypes::SVG_UNIT_TYPE_OBJECTBOUNDINGBOX) {
        AffineTransform transform;
        transform.translate(objectBoundingBox.x(), objectBoundingBox.y());
        transform.scaleNonUniform(objectBoundingBox.width(), objectBoundingBox.height());
        clipPath.transform(transform);
    }

    // Transform path by animatedLocalTransform.
    clipPath.transform(animatedLocalTransform);

    // The SVG specification wants us to clip everything, if clip-path doesn't have a child.
    if (clipPath.isEmpty())
        clipPath.addRect(FloatRect());
    context->clipPath(clipPath, clipRule);
    return true;
}

bool RenderSVGResourceClipper::drawContentIntoMaskImage(ClipperData* clipperData, const FloatRect& objectBoundingBox)
{
    ASSERT(frame());
    ASSERT(clipperData);
    ASSERT(clipperData->clipMaskImage);

    GraphicsContext* maskContext = clipperData->clipMaskImage->context();
    ASSERT(maskContext);

    AffineTransform maskContentTransformation;
    SVGClipPathElement* clipPath = static_cast<SVGClipPathElement*>(node());
    if (clipPath->clipPathUnitsCurrentValue() == SVGUnitTypes::SVG_UNIT_TYPE_OBJECTBOUNDINGBOX) {
        maskContentTransformation.translate(objectBoundingBox.x(), objectBoundingBox.y());
        maskContentTransformation.scaleNonUniform(objectBoundingBox.width(), objectBoundingBox.height());
        maskContext->concatCTM(maskContentTransformation);
    }

    // Switch to a paint behavior where all children of this <clipPath> will be rendered using special constraints:
    // - fill-opacity/stroke-opacity/opacity set to 1
    // - masker/filter not applied when rendering the children
    // - fill is set to the initial fill paint server (solid, black)
    // - stroke is set to the initial stroke paint server (none)
    PaintBehavior oldBehavior = frame()->view()->paintBehavior();
    frame()->view()->setPaintBehavior(oldBehavior | PaintBehaviorRenderingSVGMask);

    // Draw all clipPath children into a global mask.
    for (Node* childNode = node()->firstChild(); childNode; childNode = childNode->nextSibling()) {
        RenderObject* renderer = childNode->renderer();
        if (!childNode->isSVGElement() || !renderer)
            continue;
        if (renderer->needsLayout()) {
            frame()->view()->setPaintBehavior(oldBehavior);
            return false;
        }
        RenderStyle* style = renderer->style();
        if (!style || style->display() == NONE || style->visibility() != VISIBLE)
            continue;

        WindRule newClipRule = style->svgStyle()->clipRule();
        bool isUseElement = childNode->hasTagName(SVGNames::useTag);
        if (isUseElement) {
            SVGUseElement* useElement = toSVGUseElement(childNode);
            renderer = useElement->rendererClipChild();
            if (!renderer)
                continue;
            if (!useElement->hasAttribute(SVGNames::clip_ruleAttr))
                newClipRule = renderer->style()->svgStyle()->clipRule();
        }

        // Only shapes, paths and texts are allowed for clipping.
        if (!renderer->isSVGShape() && !renderer->isSVGText())
            continue;

        maskContext->setFillRule(newClipRule);

        // In the case of a <use> element, we obtained its renderere above, to retrieve its clipRule.
        // We have to pass the <use> renderer itself to renderSubtreeToImageBuffer() to apply it's x/y/transform/etc. values when rendering.
        // So if isUseElement is true, refetch the childNode->renderer(), as renderer got overriden above.
        SVGRenderingContext::renderSubtreeToImageBuffer(clipperData->clipMaskImage.get(), isUseElement ? childNode->renderer() : renderer, maskContentTransformation);
    }

    frame()->view()->setPaintBehavior(oldBehavior);
    return true;
}

static bool isDeletableElement(const Node* node)
{
    if (!node || !node->isHTMLElement() || !node->inDocument() || !node->rendererIsEditable())
        return false;

    // In general we want to only draw the UI around object of a certain area, but we still keep the min width/height to
    // make sure we don't end up with very thin or very short elements getting the UI.
    const int minimumArea = 2500;
    const int minimumWidth = 48;
    const int minimumHeight = 16;
    const unsigned minimumVisibleBorders = 1;

    RenderObject* renderer = node->renderer();
    if (!renderer || !renderer->isBox())
        return false;

    // Disallow the body element since it isn't practical to delete, and the deletion UI would be clipped.
    if (node->hasTagName(bodyTag))
        return false;

    // Disallow elements with any overflow clip, since the deletion UI would be clipped as well. <rdar://problem/6840161>
    if (renderer->hasOverflowClip())
        return false;

    // Disallow Mail blockquotes since the deletion UI would get in the way of editing for these.
    if (isMailBlockquote(node))
        return false;

    RenderBox* box = toRenderBox(renderer);
    IntRect borderBoundingBox = box->borderBoundingBox();
    if (borderBoundingBox.width() < minimumWidth || borderBoundingBox.height() < minimumHeight)
        return false;

    if ((borderBoundingBox.width() * borderBoundingBox.height()) < minimumArea)
        return false;

    if (renderer->isTable())
        return true;

    if (node->hasTagName(ulTag) || node->hasTagName(olTag) || node->hasTagName(iframeTag))
        return true;

    if (renderer->isOutOfFlowPositioned())
        return true;

    if (renderer->isRenderBlock() && !renderer->isTableCell()) {
        RenderStyle* style = renderer->style();
        if (!style)
            return false;

        // Allow blocks that have background images
        if (style->hasBackgroundImage()) {
            for (const FillLayer* background = style->backgroundLayers(); background; background = background->next()) {
                if (background->image() && background->image()->canRender(renderer, 1))
                    return true;
            }
        }

        // Allow blocks with a minimum number of non-transparent borders
        unsigned visibleBorders = style->borderTop().isVisible() + style->borderBottom().isVisible() + style->borderLeft().isVisible() + style->borderRight().isVisible();
        if (visibleBorders >= minimumVisibleBorders)
            return true;

        // Allow blocks that have a different background from it's parent
        ContainerNode* parentNode = node->parentNode();
        if (!parentNode)
            return false;

        RenderObject* parentRenderer = parentNode->renderer();
        if (!parentRenderer)
            return false;

        RenderStyle* parentStyle = parentRenderer->style();
        if (!parentStyle)
            return false;

        if (renderer->hasBackground() && (!parentRenderer->hasBackground() || style->visitedDependentColor(CSSPropertyBackgroundColor) != parentStyle->visitedDependentColor(CSSPropertyBackgroundColor)))
            return true;
    }

    return false;
}

void EllipsisBox::paint(PaintInfo& paintInfo, int tx, int ty)
{
    GraphicsContext* context = paintInfo.context;
    RenderStyle* style = m_renderer->style(m_firstLine);
    Color textColor = style->visitedDependentColor(CSSPropertyColor);
    if (textColor != context->fillColor())
        context->setFillColor(textColor, style->colorSpace());
    bool setShadow = false;
    if (style->textShadow()) {
        context->setShadow(IntSize(style->textShadow()->x(), style->textShadow()->y()),
                           style->textShadow()->blur(), style->textShadow()->color(), style->colorSpace());
        setShadow = true;
    }

    if (selectionState() != RenderObject::SelectionNone) {
        paintSelection(context, tx, ty, style, style->font());

        // Select the correct color for painting the text.
        Color foreground = paintInfo.forceBlackText ? Color::black : renderer()->selectionForegroundColor();
        if (foreground.isValid() && foreground != textColor)
            context->setFillColor(foreground, style->colorSpace());
    }

    const String& str = m_str;
    context->drawText(style->font(), TextRun(str.characters(), str.length(), false, 0, 0, false, style->visuallyOrdered()), IntPoint(m_x + tx, m_y + ty + style->font().ascent()));

    // Restore the regular fill color.
    if (textColor != context->fillColor())
        context->setFillColor(textColor, style->colorSpace());

    if (setShadow)
        context->clearShadow();

    if (m_markupBox) {
        // Paint the markup box
        tx += m_x + m_width - m_markupBox->x();
        ty += m_y + style->font().ascent() - (m_markupBox->y() + m_markupBox->renderer()->style(m_firstLine)->font().ascent());
        m_markupBox->paint(paintInfo, tx, ty);
    }
}

bool AccessibilityTable::isTableExposableThroughAccessibility()
{
    // the following is a heuristic used to determine if a
    // <table> should be exposed as an AXTable. The goal
    // is to only show "data" tables
    
    if (!m_renderer || !m_renderer->isTable())
        return false;
    
    // if the developer assigned an aria role to this, then we shouldn't 
    // expose it as a table, unless, of course, the aria role is a table
    AccessibilityRole ariaRole = ariaRoleAttribute();
    if (ariaRole == TableRole)
        return true;
    if (ariaRole != UnknownRole)
        return false;
    
    RenderTable* table = static_cast<RenderTable*>(m_renderer);
    
    // this employs a heuristic to determine if this table should appear. 
    // Only "data" tables should be exposed as tables. 
    // Unfortunately, there is no good way to determine the difference
    // between a "layout" table and a "data" table
    
    Node* tableNode = table->element();
    if (!tableNode || !tableNode->hasTagName(tableTag))
        return false;
    
    // if there is a caption element, summary, THEAD, or TFOOT section, it's most certainly a data table
    HTMLTableElement* tableElement = static_cast<HTMLTableElement*>(tableNode);
    if (!tableElement->summary().isEmpty() || tableElement->tHead() || tableElement->tFoot() || tableElement->caption())
        return true;
    
    // if someone used "rules" attribute than the table should appear
    if (!tableElement->rules().isEmpty())
        return true;    
    
    // go through the cell's and check for tell-tale signs of "data" table status
    // cells have borders, or use attributes like headers, abbr, scope or axis
    RenderTableSection* firstBody = table->firstBody();
    if (!firstBody)
        return false;
    
    int numCols = firstBody->numColumns();
    int numRows = firstBody->numRows();
    
    // if there's only one cell, it's not a good AXTable candidate
    if (numRows == 1 && numCols == 1)
        return false;
    
    // store the background color of the table to check against cell's background colors
    RenderStyle* tableStyle = table->style();
    if (!tableStyle)
        return false;
    Color tableBGColor = tableStyle->backgroundColor();
    
    // check enough of the cells to find if the table matches our criteria
    // Criteria: 
    //   1) must have at least one valid cell (and)
    //   2) at least half of cells have borders (or)
    //   3) at least half of cells have different bg colors than the table, and there is cell spacing
    unsigned validCellCount = 0;
    unsigned borderedCellCount = 0;
    unsigned backgroundDifferenceCellCount = 0;
    
    for (int row = 0; row < numRows; ++row) {
        for (int col = 0; col < numCols; ++col) {    
            RenderTableCell* cell = firstBody->cellAt(row, col).cell;
            if (!cell)
                continue;
            Node* cellNode = cell->element();
            if (!cellNode)
                continue;
            
            if (cell->width() < 1 || cell->height() < 1)
                continue;
            
            validCellCount++;
            
            HTMLTableCellElement* cellElement = static_cast<HTMLTableCellElement*>(cellNode);
            
            // in this case, the developer explicitly assigned a "data" table attribute
            if (!cellElement->headers().isEmpty() || !cellElement->abbr().isEmpty() || 
                !cellElement->axis().isEmpty() || !cellElement->scope().isEmpty())
                return true;
            
            RenderStyle* renderStyle = cell->style();
            if (!renderStyle)
                continue;

            // a cell needs to have matching bordered sides, before it can be considered a bordered cell.
            if ((cell->borderTop() > 0 && cell->borderBottom() > 0) ||
                (cell->borderLeft() > 0 && cell->borderRight() > 0))
                borderedCellCount++;
            
            // if the cell has a different color from the table and there is cell spacing,
            // then it is probably a data table cell (spacing and colors take the place of borders)
            Color cellColor = renderStyle->backgroundColor();
            if (table->hBorderSpacing() > 0 && table->vBorderSpacing() > 0 && 
                tableBGColor != cellColor && cellColor.alpha() != 1)
//.........这里部分代码省略.........

void RenderMenuList::adjustInnerStyle()
{
    RenderStyle* innerStyle = m_innerBlock->style();
    innerStyle->setFlexGrow(1);
    innerStyle->setFlexShrink(1);
    // min-width: 0; is needed for correct shrinking.
    // FIXME: Remove this line when https://bugs.webkit.org/show_bug.cgi?id=111790 is fixed.
    innerStyle->setMinWidth(Length(0, Fixed));
    // Use margin:auto instead of align-items:center to get safe centering, i.e.
    // when the content overflows, treat it the same as align-items: flex-start.
    // But we only do that for the cases where html.css would otherwise use center.
    if (style()->alignItems() == AlignCenter) {
        innerStyle->setMarginTop(Length());
        innerStyle->setMarginBottom(Length());
        innerStyle->setAlignSelf(AlignFlexStart);
    }

    innerStyle->setPaddingLeft(Length(theme()->popupInternalPaddingLeft(style()), Fixed));
    innerStyle->setPaddingRight(Length(theme()->popupInternalPaddingRight(style()), Fixed));
    innerStyle->setPaddingTop(Length(theme()->popupInternalPaddingTop(style()), Fixed));
    innerStyle->setPaddingBottom(Length(theme()->popupInternalPaddingBottom(style()), Fixed));

    if (document().page()->chrome().selectItemWritingDirectionIsNatural()) {
        // Items in the popup will not respect the CSS text-align and direction properties,
        // so we must adjust our own style to match.
        innerStyle->setTextAlign(LEFT);
        TextDirection direction = (m_buttonText && m_buttonText->text()->defaultWritingDirection() == WTF::Unicode::RightToLeft) ? RTL : LTR;
        innerStyle->setDirection(direction);
    } else if (m_optionStyle && document().page()->chrome().selectItemAlignmentFollowsMenuWritingDirection()) {
        if ((m_optionStyle->direction() != innerStyle->direction() || m_optionStyle->unicodeBidi() != innerStyle->unicodeBidi()))
            m_innerBlock->setNeedsLayoutAndPrefWidthsRecalc();
        innerStyle->setTextAlign(style()->isLeftToRightDirection() ? LEFT : RIGHT);
        innerStyle->setDirection(m_optionStyle->direction());
        innerStyle->setUnicodeBidi(m_optionStyle->unicodeBidi());
    }
}