C++ SVGSVGElement::intrinsicHeight方法代码示例

IntSize SVGImage::containerSize() const
{
    if (!m_page)
        return IntSize();
    Frame* frame = m_page->mainFrame();
    SVGSVGElement* rootElement = toSVGDocument(frame->document())->rootElement();
    if (!rootElement)
        return IntSize();

    RenderSVGRoot* renderer = toRenderSVGRoot(rootElement->renderer());
    if (!renderer)
        return IntSize();

    // If a container size is available it has precedence.
    IntSize containerSize = renderer->containerSize();
    if (!containerSize.isEmpty())
        return containerSize;

    // Assure that a container size is always given for a non-identity zoom level.
    ASSERT(renderer->style()->effectiveZoom() == 1);

    FloatSize currentSize;
    if (rootElement->intrinsicWidth().isFixed() && rootElement->intrinsicHeight().isFixed())
        currentSize = rootElement->currentViewportSize();
    else
        currentSize = rootElement->currentViewBoxRect().size();

    if (!currentSize.isEmpty())
        return IntSize(static_cast<int>(ceilf(currentSize.width())), static_cast<int>(ceilf(currentSize.height())));

    // As last resort, use CSS default intrinsic size.
    return IntSize(300, 150);
}

bool SVGImage::hasRelativeHeight() const
{
    SVGSVGElement* rootElement = this->rootElement();
    if (!rootElement)
        return false;
    return rootElement->intrinsicHeight().isPercentOrCalculated();
}

bool RenderSVGRoot::hasRelativeDimensions() const
{
    SVGSVGElement* svg = static_cast<SVGSVGElement*>(node());
    ASSERT(svg);

    return svg->intrinsicHeight(SVGSVGElement::IgnoreCSSProperties).isPercent() || svg->intrinsicWidth(SVGSVGElement::IgnoreCSSProperties).isPercent();
}

LayoutUnit RenderSVGRoot::computeReplacedLogicalHeight() const
{
    SVGSVGElement* svg = toSVGSVGElement(node());
    ASSERT(svg);

    // When we're embedded through SVGImage (border-image/background-image/<html:img>/...) we're forced to resize to a specific size.
    if (!m_containerSize.isEmpty())
        return m_containerSize.height();

    if (style()->logicalHeight().isSpecified() || style()->logicalMaxHeight().isSpecified())
        return RenderReplaced::computeReplacedLogicalHeight();

    if (svg->heightAttributeEstablishesViewport()) {
        Length height = svg->intrinsicHeight(SVGSVGElement::IgnoreCSSProperties);
        if (height.isPercent()) {
            RenderBlock* cb = containingBlock();
            ASSERT(cb);
            while (cb->isAnonymous()) {
                cb = cb->containingBlock();
                cb->addPercentHeightDescendant(const_cast<RenderSVGRoot*>(this));
            }
        } else
            RenderBlock::removePercentHeightDescendant(const_cast<RenderSVGRoot*>(this));

        return resolveLengthAttributeForSVG(height, style()->effectiveZoom(), containingBlock()->availableLogicalHeight(IncludeMarginBorderPadding), view());
    }

    // SVG embedded through object/embed/iframe.
    if (isEmbeddedThroughFrameContainingSVGDocument())
        return document()->frame()->ownerRenderer()->availableLogicalHeight(IncludeMarginBorderPadding);

    // SVG embedded via SVGImage (background-image/border-image/etc) / Inline SVG.
    return RenderReplaced::computeReplacedLogicalHeight();
}

LayoutUnit RenderSVGRoot::computeReplacedLogicalHeight() const
{
    SVGSVGElement* svg = static_cast<SVGSVGElement*>(node());
    ASSERT(svg);

    // When we're embedded through SVGImage (border-image/background-image/<html:img>/...) we're forced to resize to a specific size.
    if (!m_containerSize.isEmpty())
        return m_containerSize.height();

    if (hasReplacedLogicalHeight())
        return RenderReplaced::computeReplacedLogicalHeight();

    if (svg->heightAttributeEstablishesViewport()) {
        Length height = svg->intrinsicHeight(SVGSVGElement::IgnoreCSSProperties);
        if (height.isPercent()) {
            RenderBlock* cb = containingBlock();
            ASSERT(cb);
            while (cb->isAnonymous()) {
                cb = cb->containingBlock();
                cb->addPercentHeightDescendant(const_cast<RenderSVGRoot*>(this));
            }
        } else
            RenderBlock::removePercentHeightDescendant(const_cast<RenderSVGRoot*>(this));

        return resolveLengthAttributeForSVG(height, style()->effectiveZoom(), containingBlock()->availableLogicalHeight());
    }

    // Only SVGs embedded in <object> reach this point.
    ASSERT(isEmbeddedThroughFrameContainingSVGDocument());
    return document()->frame()->ownerRenderer()->availableLogicalHeight();
}

bool RenderSVGRoot::hasRelativeLogicalHeight() const
{
    SVGSVGElement* svg = toSVGSVGElement(node());
    ASSERT(svg);

    return svg->intrinsicHeight(SVGSVGElement::IgnoreCSSProperties).isPercent();
}

void RenderSVGRoot::computeIntrinsicRatioInformation(FloatSize& intrinsicSize, double& intrinsicRatio) const
{
    // Spec: http://www.w3.org/TR/SVG/coords.html#IntrinsicSizing
    // SVG needs to specify how to calculate some intrinsic sizing properties to enable inclusion within other languages.
    // The intrinsic width and height of the viewport of SVG content must be determined from the ‘width’ and ‘height’ attributes.
    SVGSVGElement* svg = toSVGSVGElement(node());
    ASSERT(svg);

    // The intrinsic aspect ratio of the viewport of SVG content is necessary for example, when including SVG from an ‘object’
    // element in HTML styled with CSS. It is possible (indeed, common) for an SVG graphic to have an intrinsic aspect ratio but
    // not to have an intrinsic width or height. The intrinsic aspect ratio must be calculated based upon the following rules:
    // - The aspect ratio is calculated by dividing a width by a height.
    // - If the ‘width’ and ‘height’ of the rootmost ‘svg’ element are both specified with unit identifiers (in, mm, cm, pt, pc,
    //   px, em, ex) or in user units, then the aspect ratio is calculated from the ‘width’ and ‘height’ attributes after
    //   resolving both values to user units.
    intrinsicSize.setWidth(floatValueForLength(svg->intrinsicWidth(), 0));
    intrinsicSize.setHeight(floatValueForLength(svg->intrinsicHeight(), 0));

    if (!intrinsicSize.isEmpty()) {
        intrinsicRatio = intrinsicSize.width() / static_cast<double>(intrinsicSize.height());
    } else {
        // - If either/both of the ‘width’ and ‘height’ of the rootmost ‘svg’ element are in percentage units (or omitted), the
        //   aspect ratio is calculated from the width and height values of the ‘viewBox’ specified for the current SVG document
        //   fragment. If the ‘viewBox’ is not correctly specified, or set to 'none', the intrinsic aspect ratio cannot be
        //   calculated and is considered unspecified.
        FloatSize viewBoxSize = svg->viewBox()->currentValue()->value().size();
        if (!viewBoxSize.isEmpty()) {
            // The viewBox can only yield an intrinsic ratio, not an intrinsic size.
            intrinsicRatio = viewBoxSize.width() / static_cast<double>(viewBoxSize.height());
        }
    }
}

bool SVGImage::hasRelativeHeight() const
{
    if (!m_page)
        return false;
    SVGSVGElement* rootElement = toSVGDocument(m_page->mainFrame().document())->rootElement();
    if (!rootElement)
        return false;
    return rootElement->intrinsicHeight().isPercent();
}

void RenderSVGRoot::computeIntrinsicRatioInformation(FloatSize& intrinsicSize, double& intrinsicRatio, bool& isPercentageIntrinsicSize) const
{
    // Spec: http://www.w3.org/TR/SVG/coords.html#IntrinsicSizing
    // SVG needs to specify how to calculate some intrinsic sizing properties to enable inclusion within other languages.
    // The intrinsic width and height of the viewport of SVG content must be determined from the ‘width’ and ‘height’ attributes.
    // If either of these are not specified, a value of '100%' must be assumed. Note: the ‘width’ and ‘height’ attributes are not
    // the same as the CSS width and height properties. Specifically, percentage values do not provide an intrinsic width or height,
    // and do not indicate a percentage of the containing block. Rather, once the viewport is established, they indicate the portion
    // of the viewport that is actually covered by image data.
    SVGSVGElement* svg = toSVGSVGElement(node());
    ASSERT(svg);
    Length intrinsicWidthAttribute = svg->intrinsicWidth(SVGSVGElement::IgnoreCSSProperties);
    Length intrinsicHeightAttribute = svg->intrinsicHeight(SVGSVGElement::IgnoreCSSProperties);

    // The intrinsic aspect ratio of the viewport of SVG content is necessary for example, when including SVG from an ‘object’
    // element in HTML styled with CSS. It is possible (indeed, common) for an SVG graphic to have an intrinsic aspect ratio but
    // not to have an intrinsic width or height. The intrinsic aspect ratio must be calculated based upon the following rules:
    // - The aspect ratio is calculated by dividing a width by a height.
    // - If the ‘width’ and ‘height’ of the rootmost ‘svg’ element are both specified with unit identifiers (in, mm, cm, pt, pc,
    //   px, em, ex) or in user units, then the aspect ratio is calculated from the ‘width’ and ‘height’ attributes after
    //   resolving both values to user units.
    if (intrinsicWidthAttribute.isFixed() || intrinsicHeightAttribute.isFixed()) {
        if (intrinsicWidthAttribute.isFixed())
            intrinsicSize.setWidth(floatValueForLength(intrinsicWidthAttribute, 0));
        if (intrinsicHeightAttribute.isFixed())
            intrinsicSize.setHeight(floatValueForLength(intrinsicHeightAttribute, 0));
        if (!intrinsicSize.isEmpty())
            intrinsicRatio = intrinsicSize.width() / static_cast<double>(intrinsicSize.height());
        return;
    }

    // - If either/both of the ‘width’ and ‘height’ of the rootmost ‘svg’ element are in percentage units (or omitted), the
    //   aspect ratio is calculated from the width and height values of the ‘viewBox’ specified for the current SVG document
    //   fragment. If the ‘viewBox’ is not correctly specified, or set to 'none', the intrinsic aspect ratio cannot be
    //   calculated and is considered unspecified.
    intrinsicSize = svg->viewBox().size();
    if (!intrinsicSize.isEmpty()) {
        // The viewBox can only yield an intrinsic ratio, not an intrinsic size.
        intrinsicRatio = intrinsicSize.width() / static_cast<double>(intrinsicSize.height());
        intrinsicSize = FloatSize();
        return;
    }

    // If our intrinsic size is in percentage units, return those to the caller through the intrinsicSize. Notify the caller
    // about the special situation, by setting isPercentageIntrinsicSize=true, so it knows how to interpret the return values.
    if (intrinsicWidthAttribute.isPercent() && intrinsicHeightAttribute.isPercent()) {
        isPercentageIntrinsicSize = true;
        intrinsicSize = FloatSize(intrinsicWidthAttribute.percent(), intrinsicHeightAttribute.percent());
    }
}

void SVGImage::computeIntrinsicDimensions(Length& intrinsicWidth, Length& intrinsicHeight, FloatSize& intrinsicRatio)
{
    SVGSVGElement* rootElement = this->rootElement();
    if (!rootElement)
        return;

    intrinsicWidth = rootElement->intrinsicWidth();
    intrinsicHeight = rootElement->intrinsicHeight();
    if (rootElement->preserveAspectRatio().align() == SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_NONE)
        return;

    intrinsicRatio = rootElement->viewBox().size();
    if (intrinsicRatio.isEmpty() && intrinsicWidth.isFixed() && intrinsicHeight.isFixed())
        intrinsicRatio = FloatSize(floatValueForLength(intrinsicWidth, 0), floatValueForLength(intrinsicHeight, 0));
}

void SVGImage::computeIntrinsicDimensions(Length& intrinsicWidth, Length& intrinsicHeight, FloatSize& intrinsicRatio)
{
    if (!m_page)
        return;
    Frame* frame = m_page->mainFrame();
    SVGSVGElement* rootElement = static_cast<SVGDocument*>(frame->document())->rootElement();
    if (!rootElement)
        return;

    intrinsicWidth = rootElement->intrinsicWidth();
    intrinsicHeight = rootElement->intrinsicHeight();
    if (rootElement->preserveAspectRatio().align() == SVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_NONE)
        return;

    intrinsicRatio = rootElement->viewBox().size();
    if (intrinsicRatio.isEmpty() && intrinsicWidth.isFixed() && intrinsicHeight.isFixed())
        intrinsicRatio = FloatSize(intrinsicWidth.calcFloatValue(0), intrinsicHeight.calcFloatValue(0));
}

LayoutUnit RenderSVGRoot::computeReplacedLogicalHeight() const
{
    SVGSVGElement* svg = toSVGSVGElement(node());
    ASSERT(svg);

    // When we're embedded through SVGImage (border-image/background-image/<html:img>/...) we're forced to resize to a specific size.
    if (!m_containerSize.isEmpty())
        return m_containerSize.height();

    if (isEmbeddedThroughFrameContainingSVGDocument())
        return containingBlock()->availableLogicalHeight(IncludeMarginBorderPadding);

    if (style()->logicalHeight().isSpecified() || style()->logicalMaxHeight().isSpecified())
        return RenderReplaced::computeReplacedLogicalHeight();

    if (svg->hasIntrinsicHeight())
        return resolveLengthAttributeForSVG(svg->intrinsicHeight(), style()->effectiveZoom(), containingBlock()->availableLogicalHeight(IncludeMarginBorderPadding).toFloat());

    // SVG embedded via SVGImage (background-image/border-image/etc) / Inline SVG.
    return RenderReplaced::computeReplacedLogicalHeight();
}

FloatSize LayoutSVGRoot::calculateIntrinsicSize() const
{
    SVGSVGElement* svg = toSVGSVGElement(node());
    ASSERT(svg);

    return FloatSize(floatValueForLength(svg->intrinsicWidth(), 0), floatValueForLength(svg->intrinsicHeight(), 0));
}