C++ TreeScope::document方法代码示例

void TreeScope::setParentTreeScope(TreeScope& newParentScope) {
  // A document node cannot be re-parented.
  DCHECK(!rootNode().isDocumentNode());

  m_parentTreeScope = &newParentScope;
  setDocument(newParentScope.document());
}

AtomicString SVGURIReference::fragmentIdentifierFromIRIString(
    const String& urlString,
    const TreeScope& treeScope) {
  SVGURLReferenceResolver resolver(urlString, treeScope.document());
  if (!resolver.isLocal())
    return emptyAtom;
  return resolver.fragmentIdentifier();
}

void TreeScope::setParentTreeScope(TreeScope& newParentScope)
{
    // A document node cannot be re-parented.
    ASSERT(!rootNode().isDocumentNode());

    newParentScope.guardRef();
    if (m_parentTreeScope)
        m_parentTreeScope->guardDeref();
    m_parentTreeScope = &newParentScope;
    setDocument(newParentScope.document());
}

AtomicString SVGURIReference::fragmentIdentifierFromIRIString(const String& url, const TreeScope& treeScope)
{
    size_t start = url.find('#');
    if (start == kNotFound)
        return emptyAtom;

    const Document& document = treeScope.document();
    KURL base = start ? KURL(document.baseURI(), url.substring(0, start)) : document.baseURI();
    if (equalIgnoringFragmentIdentifier(base, document.url()))
        return AtomicString(url.substring(start + 1));

    return emptyAtom;
}

static inline KURL urlFromIRIStringWithFragmentIdentifier(const String& url, const TreeScope& treeScope, AtomicString& fragmentIdentifier)
{
    size_t startOfFragmentIdentifier = url.find('#');
    if (startOfFragmentIdentifier == kNotFound)
        return KURL();

    const Document& document = treeScope.document();

    // Exclude the '#' character when determining the fragmentIdentifier.
    fragmentIdentifier = AtomicString(url.substring(startOfFragmentIdentifier + 1));
    if (startOfFragmentIdentifier) {
        KURL base(document.baseURI(), url.substring(0, startOfFragmentIdentifier));
        return KURL(base, url.substring(startOfFragmentIdentifier));
    }

    return KURL(document.baseURI(), url.substring(startOfFragmentIdentifier));
}

void ScopedStyleResolver::keyframesRulesAdded(const TreeScope& treeScope) {
  // Called when @keyframes rules are about to be added/removed from a
  // TreeScope. @keyframes rules may apply to animations on elements in the
  // same TreeScope as the stylesheet, or the host element in the parent
  // TreeScope if the TreeScope is a shadow tree.

  ScopedStyleResolver* resolver = treeScope.scopedStyleResolver();
  ScopedStyleResolver* parentResolver =
      treeScope.parentTreeScope()
          ? treeScope.parentTreeScope()->scopedStyleResolver()
          : nullptr;

  bool hadUnresolvedKeyframes = false;
  if (resolver && resolver->m_hasUnresolvedKeyframesRule) {
    resolver->m_hasUnresolvedKeyframesRule = false;
    hadUnresolvedKeyframes = true;
  }
  if (parentResolver && parentResolver->m_hasUnresolvedKeyframesRule) {
    parentResolver->m_hasUnresolvedKeyframesRule = false;
    hadUnresolvedKeyframes = true;
  }

  if (hadUnresolvedKeyframes) {
    // If an animation ended up not being started because no @keyframes
    // rules were found for the animation-name, we need to recalculate style
    // for the elements in the scope, including its shadow host if
    // applicable.
    invalidationRootForTreeScope(treeScope).setNeedsStyleRecalc(
        SubtreeStyleChange, StyleChangeReasonForTracing::create(
                                StyleChangeReason::StyleSheetChange));
    return;
  }

  // If we have animations running, added/removed @keyframes may affect these.
  treeScope.document().timeline().invalidateKeyframeEffects(treeScope);
}

PassRefPtr<FilterEffect> ReferenceFilterBuilder::build(Filter* parentFilter, RenderObject* renderer, FilterEffect* previousEffect, const ReferenceFilterOperation* filterOperation)
{
    if (!renderer)
        return nullptr;

    TreeScope* treeScope = &renderer->node()->treeScope();

    if (DocumentResourceReference* documentResourceRef = documentResourceReference(filterOperation)) {
        DocumentResource* cachedSVGDocument = documentResourceRef->document();

        // If we have an SVG document, this is an external reference. Otherwise
        // we look up the referenced node in the current document.
        if (cachedSVGDocument)
            treeScope = cachedSVGDocument->document();
    }

    if (!treeScope)
        return nullptr;

    Element* filter = treeScope->getElementById(filterOperation->fragment());

    if (!filter) {
        // Although we did not find the referenced filter, it might exist later
        // in the document.
        treeScope->document().accessSVGExtensions().addPendingResource(filterOperation->fragment(), toElement(renderer->node()));
        return nullptr;
    }

    if (!isSVGFilterElement(*filter))
        return nullptr;

    SVGFilterElement& filterElement = toSVGFilterElement(*filter);

    // FIXME: Figure out what to do with SourceAlpha. Right now, we're
    // using the alpha of the original input layer, which is obviously
    // wrong. We should probably be extracting the alpha from the
    // previousEffect, but this requires some more processing.
    // This may need a spec clarification.
    RefPtr<SVGFilterBuilder> builder = SVGFilterBuilder::create(previousEffect, SourceAlpha::create(parentFilter));

    ColorSpace filterColorSpace = ColorSpaceDeviceRGB;
    bool useFilterColorSpace = getSVGElementColorSpace(&filterElement, filterColorSpace);

    for (SVGElement* element = Traversal<SVGElement>::firstChild(filterElement); element; element = Traversal<SVGElement>::nextSibling(*element)) {
        if (!element->isFilterEffect())
            continue;

        SVGFilterPrimitiveStandardAttributes* effectElement = static_cast<SVGFilterPrimitiveStandardAttributes*>(element);

        RefPtr<FilterEffect> effect = effectElement->build(builder.get(), parentFilter);
        if (!effect)
            continue;

        effectElement->setStandardAttributes(effect.get());
        effect->setEffectBoundaries(SVGLengthContext::resolveRectangle<SVGFilterPrimitiveStandardAttributes>(effectElement, filterElement.primitiveUnits()->currentValue()->enumValue(), parentFilter->sourceImageRect()));
        ColorSpace colorSpace = filterColorSpace;
        if (useFilterColorSpace || getSVGElementColorSpace(effectElement, colorSpace))
            effect->setOperatingColorSpace(colorSpace);
        builder->add(AtomicString(effectElement->result()->currentValue()->value()), effect);
    }
    return builder->lastEffect();
}