C++ LayoutView::location方法代码示例

static void frameContentAsPlainText(size_t maxChars, LocalFrame* frame, StringBuilder& output)
{
    Document* document = frame->document();
    if (!document)
        return;

    if (!frame->view())
        return;

    // Select the document body.
    if (document->body()) {
        const EphemeralRange range = EphemeralRange::rangeOfContents(*document->body());

        // The text iterator will walk nodes giving us text. This is similar to
        // the plainText() function in core/editing/TextIterator.h, but we implement the maximum
        // size and also copy the results directly into a wstring, avoiding the
        // string conversion.
        for (TextIterator it(range.startPosition(), range.endPosition()); !it.atEnd(); it.advance()) {
            it.text().appendTextToStringBuilder(output, 0, maxChars - output.length());
            if (output.length() >= maxChars)
                return; // Filled up the buffer.
        }
    }

    // The separator between frames when the frames are converted to plain text.
    const LChar frameSeparator[] = { '\n', '\n' };
    const size_t frameSeparatorLength = WTF_ARRAY_LENGTH(frameSeparator);

    // Recursively walk the children.
    const FrameTree& frameTree = frame->tree();
    for (Frame* curChild = frameTree.firstChild(); curChild; curChild = curChild->tree().nextSibling()) {
        if (!curChild->isLocalFrame())
            continue;
        LocalFrame* curLocalChild = toLocalFrame(curChild);
        // Ignore the text of non-visible frames.
        LayoutView* contentLayoutObject = curLocalChild->contentLayoutObject();
        LayoutPart* ownerLayoutObject = curLocalChild->ownerLayoutObject();
        if (!contentLayoutObject || !contentLayoutObject->size().width() || !contentLayoutObject->size().height()
            || (contentLayoutObject->location().x() + contentLayoutObject->size().width() <= 0) || (contentLayoutObject->location().y() + contentLayoutObject->size().height() <= 0)
            || (ownerLayoutObject && ownerLayoutObject->style() && ownerLayoutObject->style()->visibility() != VISIBLE)) {
            continue;
        }

        // Make sure the frame separator won't fill up the buffer, and give up if
        // it will. The danger is if the separator will make the buffer longer than
        // maxChars. This will cause the computation above:
        //   maxChars - output->size()
        // to be a negative number which will crash when the subframe is added.
        if (output.length() >= maxChars - frameSeparatorLength)
            return;

        output.append(frameSeparator, frameSeparatorLength);
        frameContentAsPlainText(maxChars, curLocalChild, output);
        if (output.length() >= maxChars)
            return; // Filled up the buffer.
    }
}

void PaintPropertyTreeBuilder::buildTreeNodes(
    FrameView& frameView,
    PaintPropertyTreeBuilderContext& context) {
  if (RuntimeEnabledFeatures::rootLayerScrollingEnabled()) {
    LayoutView* layoutView = frameView.layoutView();
    if (!layoutView)
      return;

    TransformationMatrix frameTranslate;
    frameTranslate.translate(frameView.x() + layoutView->location().x() +
                                 context.current.paintOffset.x(),
                             frameView.y() + layoutView->location().y() +
                                 context.current.paintOffset.y());
    context.current.transform =
        layoutView->getMutableForPainting()
            .ensurePaintProperties()
            .updatePaintOffsetTranslation(context.current.transform,
                                          frameTranslate, FloatPoint3D());
    context.current.paintOffset = LayoutPoint();
    context.current.renderingContextID = 0;
    context.current.shouldFlattenInheritedTransform = true;
    context.absolutePosition = context.current;
    context.containerForAbsolutePosition =
        nullptr;  // This will get set in updateOutOfFlowContext().
    context.fixedPosition = context.current;
    return;
  }

  TransformationMatrix frameTranslate;
  frameTranslate.translate(frameView.x() + context.current.paintOffset.x(),
                           frameView.y() + context.current.paintOffset.y());
  context.current.transform = updateFrameViewPreTranslation(
      frameView, context.current.transform, frameTranslate, FloatPoint3D());

  FloatRoundedRect contentClip(
      IntRect(IntPoint(), frameView.visibleContentSize()));
  context.current.clip = updateFrameViewContentClip(
      frameView, context.current.clip, frameView.preTranslation(), contentClip);

  // Record the fixed properties before any scrolling occurs.
  const auto* fixedTransformNode = context.current.transform;
  auto* fixedScrollNode = context.current.scroll;

  ScrollOffset scrollOffset = frameView.scrollOffset();
  if (frameView.isScrollable() || !scrollOffset.isZero()) {
    TransformationMatrix frameScroll;
    frameScroll.translate(-scrollOffset.width(), -scrollOffset.height());
    context.current.transform = updateFrameViewScrollTranslation(
        frameView, frameView.preTranslation(), frameScroll, FloatPoint3D());

    IntSize scrollClip = frameView.visibleContentSize();
    IntSize scrollBounds = frameView.contentsSize();
    bool userScrollableHorizontal =
        frameView.userInputScrollable(HorizontalScrollbar);
    bool userScrollableVertical =
        frameView.userInputScrollable(VerticalScrollbar);
    context.current.scroll = updateFrameViewScroll(
        frameView, context.current.scroll, frameView.scrollTranslation(),
        scrollClip, scrollBounds, userScrollableHorizontal,
        userScrollableVertical);
  } else {
    // Ensure pre-existing properties are cleared when there is no scrolling.
    frameView.setScrollTranslation(nullptr);
    frameView.setScroll(nullptr);
  }

  // Initialize the context for current, absolute and fixed position cases.
  // They are the same, except that scroll translation does not apply to
  // fixed position descendants.
  context.current.paintOffset = LayoutPoint();
  context.current.renderingContextID = 0;
  context.current.shouldFlattenInheritedTransform = true;
  context.absolutePosition = context.current;
  context.containerForAbsolutePosition = nullptr;
  context.fixedPosition = context.current;
  context.fixedPosition.transform = fixedTransformNode;
  context.fixedPosition.scroll = fixedScrollNode;

  std::unique_ptr<PropertyTreeState> contentsState(
      new PropertyTreeState(context.current.transform, context.current.clip,
                            context.currentEffect, context.current.scroll));
  frameView.setTotalPropertyTreeStateForContents(std::move(contentsState));
}