C++ SVGFilterElement::firstChild方法代码示例

PassRefPtr<SVGFilterBuilder> RenderSVGResourceFilter::buildPrimitives(SVGFilter* filter)
{
    SVGFilterElement* filterElement = static_cast<SVGFilterElement*>(node());
    FloatRect targetBoundingBox = filter->targetBoundingBox();

    // Add effects to the builder
    RefPtr<SVGFilterBuilder> builder = SVGFilterBuilder::create(filter);
    for (Node* node = filterElement->firstChild(); node; node = node->nextSibling()) {
        if (!node->isSVGElement())
            continue;

        SVGElement* element = static_cast<SVGElement*>(node);
        if (!element->isFilterEffect())
            continue;

        SVGFilterPrimitiveStandardAttributes* effectElement = static_cast<SVGFilterPrimitiveStandardAttributes*>(element);
        RefPtr<FilterEffect> effect = effectElement->build(builder.get(), filter);
        if (!effect) {
            builder->clearEffects();
            return 0;
        }
        builder->appendEffectToEffectReferences(effect, effectElement->renderer());
        effectElement->setStandardAttributes(effect.get());
        effect->setEffectBoundaries(SVGLengthContext::resolveRectangle<SVGFilterPrimitiveStandardAttributes>(effectElement, filterElement->primitiveUnits(), targetBoundingBox));
        builder->add(effectElement->result(), effect);
    }
    return builder.release();
}

PassRefPtr<SVGFilterBuilder> RenderSVGResourceFilter::buildPrimitives(Filter* filter)
{
    SVGFilterElement* filterElement = static_cast<SVGFilterElement*>(node());
    bool primitiveBoundingBoxMode = filterElement->primitiveUnits() == SVGUnitTypes::SVG_UNIT_TYPE_OBJECTBOUNDINGBOX;

    // Add effects to the builder
    RefPtr<SVGFilterBuilder> builder = SVGFilterBuilder::create(filter);
    for (Node* node = filterElement->firstChild(); node; node = node->nextSibling()) {
        if (!node->isSVGElement())
            continue;

        SVGElement* element = static_cast<SVGElement*>(node);
        if (!element->isFilterEffect())
            continue;

        SVGFilterPrimitiveStandardAttributes* effectElement = static_cast<SVGFilterPrimitiveStandardAttributes*>(element);
        RefPtr<FilterEffect> effect = effectElement->build(builder.get(), filter);
        if (!effect) {
            builder->clearEffects();
            return 0;
        }
        builder->appendEffectToEffectReferences(effect);
        effectElement->setStandardAttributes(primitiveBoundingBoxMode, effect.get());
        builder->add(effectElement->result(), effect);
    }
    return builder.release();
}

PassRefPtr<FilterEffect> ReferenceFilterBuilder::build(Filter* parentFilter, RenderObject* renderer, FilterEffect* previousEffect, const ReferenceFilterOperation* filterOperation)
{
    if (!renderer)
        return 0;

    Document* document = &renderer->document();

    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)
            document = cachedSVGDocument->document();
    }

    if (!document)
        return 0;

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

    if (!filter) {
        // Although we did not find the referenced filter, it might exist later
        // in the document
        document->accessSVGExtensions()->addPendingResource(filterOperation->fragment(), toElement(renderer->node()));
        return 0;
    }

    if (!filter->isSVGElement() || !filter->hasTagName(SVGNames::filterTag))
        return 0;

    SVGFilterElement* filterElement = toSVGFilterElement(toSVGElement(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 (Node* node = filterElement->firstChild(); node; node = node->nextSibling()) {
        if (!node->isSVGElement())
            continue;

        SVGElement* element = toSVGElement(node);
        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->primitiveUnitsCurrentValue(), parentFilter->sourceImageRect()));
        ColorSpace colorSpace = filterColorSpace;
        if (useFilterColorSpace || getSVGElementColorSpace(effectElement, colorSpace))
            effect->setOperatingColorSpace(colorSpace);
        builder->add(effectElement->resultCurrentValue(), effect);
    }
    return builder->lastEffect();
}