C++ (Cpp) SVGSVGElement::GetCurrentViewElement示例

示例#1

/* virtual */ nsSize
nsSVGOuterSVGFrame::GetIntrinsicRatio()
{
  // We only have an intrinsic size/ratio if our width and height attributes
  // are both specified and set to non-percentage values, or we have a viewBox
  // rect: http://www.w3.org/TR/SVGMobile12/coords.html#IntrinsicSizing

  SVGSVGElement *content = static_cast<SVGSVGElement*>(mContent);
  nsSVGLength2 &width  = content->mLengthAttributes[SVGSVGElement::ATTR_WIDTH];
  nsSVGLength2 &height = content->mLengthAttributes[SVGSVGElement::ATTR_HEIGHT];

  if (!width.IsPercentage() && !height.IsPercentage()) {
    nsSize ratio(NSToCoordRoundWithClamp(width.GetAnimValue(content)),
                 NSToCoordRoundWithClamp(height.GetAnimValue(content)));
    if (ratio.width < 0) {
      ratio.width = 0;
    }
    if (ratio.height < 0) {
      ratio.height = 0;
    }
    return ratio;
  }

  SVGViewElement* viewElement = content->GetCurrentViewElement();
  const nsSVGViewBoxRect* viewbox = nullptr;

  // The logic here should match HasViewBox().
  if (viewElement && viewElement->mViewBox.HasRect()) {
    viewbox = &viewElement->mViewBox.GetAnimValue();
  } else if (content->mViewBox.HasRect()) {
    viewbox = &content->mViewBox.GetAnimValue();
  }

  if (viewbox) {
    float viewBoxWidth = viewbox->width;
    float viewBoxHeight = viewbox->height;

    if (viewBoxWidth < 0.0f) {
      viewBoxWidth = 0.0f;
    }
    if (viewBoxHeight < 0.0f) {
      viewBoxHeight = 0.0f;
    }
    return nsSize(NSToCoordRoundWithClamp(viewBoxWidth),
                  NSToCoordRoundWithClamp(viewBoxHeight));
  }

  return nsSVGOuterSVGFrameBase::GetIntrinsicRatio();
}