C++ nsCOMPtr::GetHeight方法代码示例

bool
nsSVGImageFrame::TransformContextForPainting(gfxContext* aGfxContext,
                                             const gfxMatrix& aTransform)
{
  gfx::Matrix imageTransform;
  if (mImageContainer->GetType() == imgIContainer::TYPE_VECTOR) {
    imageTransform = GetVectorImageTransform() * ToMatrix(aTransform);
  } else {
    int32_t nativeWidth, nativeHeight;
    if (NS_FAILED(mImageContainer->GetWidth(&nativeWidth)) ||
        NS_FAILED(mImageContainer->GetHeight(&nativeHeight)) ||
        nativeWidth == 0 || nativeHeight == 0) {
      return false;
    }
    imageTransform =
      GetRasterImageTransform(nativeWidth, nativeHeight) * ToMatrix(aTransform);

    // NOTE: We need to cancel out the effects of Full-Page-Zoom, or else
    // it'll get applied an extra time by DrawSingleUnscaledImage.
    nscoord appUnitsPerDevPx = PresContext()->AppUnitsPerDevPixel();
    gfxFloat pageZoomFactor =
      nsPresContext::AppUnitsToFloatCSSPixels(appUnitsPerDevPx);
    imageTransform.PreScale(pageZoomFactor, pageZoomFactor);
  }

  if (imageTransform.IsSingular()) {
    return false;
  }

  aGfxContext->Multiply(ThebesMatrix(imageTransform));
  return true;
}

nsIFrame*
nsSVGImageFrame::GetFrameForPoint(const gfxPoint& aPoint)
{
  if (!(GetStateBits() & NS_STATE_SVG_CLIPPATH_CHILD) && !GetHitTestFlags()) {
    return nullptr;
  }

  Rect rect;
  SVGImageElement *element = static_cast<SVGImageElement*>(mContent);
  element->GetAnimatedLengthValues(&rect.x, &rect.y,
                                   &rect.width, &rect.height, nullptr);

  if (!rect.Contains(ToPoint(aPoint))) {
    return nullptr;
  }

  // Special case for raster images -- we only want to accept points that fall
  // in the underlying image's (scaled to fit) native bounds.  That region
  // doesn't necessarily map to our <image> element's [x,y,width,height] if the
  // raster image's aspect ratio is being preserved.  We have to look up the
  // native image size & our viewBox transform in order to filter out points
  // that fall outside that area.  (This special case doesn't apply to vector
  // images because they don't limit their drawing to explicit "native
  // bounds" -- they have an infinite canvas on which to place content.)
  if (StyleDisplay()->IsScrollableOverflow() && mImageContainer) {
    if (mImageContainer->GetType() == imgIContainer::TYPE_RASTER) {
      int32_t nativeWidth, nativeHeight;
      if (NS_FAILED(mImageContainer->GetWidth(&nativeWidth)) ||
          NS_FAILED(mImageContainer->GetHeight(&nativeHeight)) ||
          nativeWidth == 0 || nativeHeight == 0) {
        return nullptr;
      }
      Matrix viewBoxTM =
        SVGContentUtils::GetViewBoxTransform(rect.width, rect.height,
                                             0, 0, nativeWidth, nativeHeight,
                                             element->mPreserveAspectRatio);
      if (!nsSVGUtils::HitTestRect(viewBoxTM,
                                   0, 0, nativeWidth, nativeHeight,
                                   aPoint.x - rect.x, aPoint.y - rect.y)) {
        return nullptr;
      }
    }
  }

  return this;
}