C++ LayoutSize函数代码示例

void PaintInvalidationState::applyClipIfNeeded(const LayoutObject& layoutObject)
{
    if (!layoutObject.hasOverflowClip())
        return;

    const LayoutBox& box = toLayoutBox(layoutObject);

    // Do not clip scroll layer contents because the compositor expects the whole layer
    // to be always invalidated in-time.
    if (box.usesCompositedScrolling())
        ASSERT(!m_clipped); // The box should establish paint invalidation container, so no m_clipped inherited.
    else
        addClipRectRelativeToPaintOffset(LayoutSize(box.layer()->size()));

    m_paintOffset -= box.scrolledContentOffset();
}

bool ExclusionShapeInsideInfo::adjustLogicalLineTop(float minSegmentWidth)
{
    const ExclusionShape* shape = computedShape();
    if (!shape || m_lineHeight <= 0 || logicalLineTop() > shapeLogicalBottom())
        return false;

    LayoutUnit newLineTop;
    if (shape->firstIncludedIntervalLogicalTop(m_shapeLineTop, LayoutSize(minSegmentWidth, m_lineHeight), newLineTop)) {
        if (newLineTop > m_shapeLineTop) {
            m_shapeLineTop = newLineTop;
            return true;
        }
    }

    return false;
}

void ImagePainter::paintIntoRect(GraphicsContext& context,
                                 const LayoutRect& destRect,
                                 const LayoutRect& contentRect) {
  if (!m_layoutImage.imageResource()->hasImage() ||
      m_layoutImage.imageResource()->errorOccurred())
    return;  // FIXME: should we just ASSERT these conditions? (audit all
             // callers).

  IntRect pixelSnappedDestRect = pixelSnappedIntRect(destRect);
  if (pixelSnappedDestRect.isEmpty())
    return;

  RefPtr<Image> image = m_layoutImage.imageResource()->image(
      pixelSnappedDestRect.size(), m_layoutImage.style()->effectiveZoom());
  if (!image || image->isNull())
    return;

  // FIXME: why is interpolation quality selection not included in the
  // Instrumentation reported cost of drawing an image?
  InterpolationQuality interpolationQuality =
      BoxPainter::chooseInterpolationQuality(
          m_layoutImage, image.get(), image.get(),
          LayoutSize(pixelSnappedDestRect.size()));

  FloatRect srcRect = image->rect();
  // If the content rect requires clipping, adjust |srcRect| and
  // |pixelSnappedDestRect| over using a clip.
  if (!contentRect.contains(destRect)) {
    IntRect pixelSnappedContentRect = pixelSnappedIntRect(contentRect);
    pixelSnappedContentRect.intersect(pixelSnappedDestRect);
    if (pixelSnappedContentRect.isEmpty())
      return;
    srcRect = mapRect(pixelSnappedContentRect, pixelSnappedDestRect, srcRect);
    pixelSnappedDestRect = pixelSnappedContentRect;
  }

  TRACE_EVENT1(TRACE_DISABLED_BY_DEFAULT("devtools.timeline"), "PaintImage",
               "data", InspectorPaintImageEvent::data(m_layoutImage));

  InterpolationQuality previousInterpolationQuality =
      context.imageInterpolationQuality();
  context.setImageInterpolationQuality(interpolationQuality);
  context.drawImage(
      image.get(), pixelSnappedDestRect, &srcRect, SkXfermode::kSrcOver_Mode,
      LayoutObject::shouldRespectImageOrientation(&m_layoutImage));
  context.setImageInterpolationQuality(previousInterpolationQuality);
}

void IntersectionObservation::clipToRoot(LayoutRect& rect)
{
    // Map and clip rect into root element coordinates.
    // TODO(szager): the writing mode flipping needs a test.
    ASSERT(m_target);
    LayoutObject* rootLayoutObject = m_observer->rootLayoutObject();
    LayoutObject* targetLayoutObject = target()->layoutObject();
    targetLayoutObject->mapToVisibleRectInAncestorSpace(toLayoutBoxModelObject(rootLayoutObject), rect, nullptr);
    if (rootLayoutObject->hasOverflowClip()) {
        LayoutBox* rootLayoutBox = toLayoutBox(rootLayoutObject);
        LayoutRect clipRect(LayoutPoint(), LayoutSize(rootLayoutBox->layer()->size()));
        m_observer->applyRootMargin(clipRect);
        rootLayoutBox->flipForWritingMode(rect);
        rect.intersect(clipRect);
        rootLayoutBox->flipForWritingMode(rect);
    }
}

static void applyClipRects(const ClipRectsContext& context,
                           const LayoutBoxModelObject& layoutObject,
                           LayoutPoint offset,
                           ClipRects& clipRects) {
  DCHECK(layoutObject.hasClipRelatedProperty() ||
         (layoutObject.isSVGRoot() &&
          toLayoutSVGRoot(&layoutObject)->shouldApplyViewportClip()));
  LayoutView* view = layoutObject.view();
  DCHECK(view);
  if (clipRects.fixed() && context.rootLayer->layoutObject() == view)
    offset -= LayoutSize(view->frameView()->scrollOffset());
  if (layoutObject.hasOverflowClip() ||
      (layoutObject.isSVGRoot() &&
       toLayoutSVGRoot(&layoutObject)->shouldApplyViewportClip()) ||
      (layoutObject.styleRef().containsPaint() && layoutObject.isBox())) {
    ClipRect newOverflowClip =
        toLayoutBox(layoutObject)
            .overflowClipRect(offset, context.overlayScrollbarClipBehavior);
    newOverflowClip.setHasRadius(layoutObject.styleRef().hasBorderRadius());
    clipRects.setOverflowClipRect(
        intersection(newOverflowClip, clipRects.overflowClipRect()));
    if (layoutObject.isPositioned())
      clipRects.setPosClipRect(
          intersection(newOverflowClip, clipRects.posClipRect()));
    if (layoutObject.isLayoutView())
      clipRects.setFixedClipRect(
          intersection(newOverflowClip, clipRects.fixedClipRect()));
    if (layoutObject.styleRef().containsPaint()) {
      clipRects.setPosClipRect(
          intersection(newOverflowClip, clipRects.posClipRect()));
      clipRects.setFixedClipRect(
          intersection(newOverflowClip, clipRects.fixedClipRect()));
    }
  }
  if (layoutObject.hasClip()) {
    LayoutRect newClip = toLayoutBox(layoutObject).clipRect(offset);
    clipRects.setPosClipRect(
        intersection(newClip, clipRects.posClipRect()).setIsClippedByClipCss());
    clipRects.setOverflowClipRect(
        intersection(newClip, clipRects.overflowClipRect())
            .setIsClippedByClipCss());
    clipRects.setFixedClipRect(intersection(newClip, clipRects.fixedClipRect())
                                   .setIsClippedByClipCss());
  }
}

void RenderGeometryMap::push(const RenderObject* renderer, const TransformationMatrix& t, bool accumulatingTransform, bool isNonUniform, bool isFixedPosition, bool hasTransform, LayoutSize offsetForFixedPosition)
{
    ASSERT(m_insertionPosition != kNotFound);
    ASSERT(!renderer->isRenderView() || !m_insertionPosition || m_mapCoordinatesFlags & TraverseDocumentBoundaries);
    ASSERT(offsetForFixedPosition.isZero() || renderer->isRenderView());

    m_mapping.insert(m_insertionPosition, RenderGeometryMapStep(renderer, accumulatingTransform, isNonUniform, isFixedPosition, hasTransform));

    RenderGeometryMapStep& step = m_mapping[m_insertionPosition];
    step.m_offsetForFixedPosition = offsetForFixedPosition;

    if (!t.isIntegerTranslation())
        step.m_transform = adoptPtr(new TransformationMatrix(t));
    else
        step.m_offset = LayoutSize(t.e(), t.f());

    stepInserted(step);
}

void EllipsisBox::paint(PaintInfo& paintInfo, const LayoutPoint& paintOffset, LayoutUnit lineTop, LayoutUnit lineBottom)
{
    GraphicsContext* context = paintInfo.context;
    RenderStyle* style = renderer().style(isFirstLineStyle());

    const Font& font = style->font();
    FloatPoint boxOrigin = locationIncludingFlipping();
    boxOrigin.moveBy(FloatPoint(paintOffset));
    FloatRect boxRect(boxOrigin, LayoutSize(logicalWidth(), virtualLogicalHeight()));
    GraphicsContextStateSaver stateSaver(*context);
    FloatPoint textOrigin = FloatPoint(boxOrigin.x(), boxOrigin.y() + font.fontMetrics().ascent());

    Color styleTextColor = renderer().resolveColor(style, CSSPropertyWebkitTextFillColor);
    if (styleTextColor != context->fillColor())
        context->setFillColor(styleTextColor);

    if (selectionState() != RenderObject::SelectionNone) {
        paintSelection(context, boxOrigin, style, font);

        // Select the correct color for painting the text.
        Color foreground = paintInfo.forceBlackText() ? Color::black : renderer().selectionForegroundColor();
        if (foreground != styleTextColor)
            context->setFillColor(foreground);
    }

    const ShadowList* shadowList = style->textShadow();
    bool hasShadow = shadowList;
    if (hasShadow)
        context->setDrawLooper(shadowList->createDrawLooper(DrawLooperBuilder::ShadowIgnoresAlpha));

    TextRun textRun = constructTextRun(&renderer(), font, m_str, style, TextRun::AllowTrailingExpansion);
    TextRunPaintInfo textRunPaintInfo(textRun);
    textRunPaintInfo.bounds = boxRect;
    context->drawText(font, textRunPaintInfo, textOrigin);

    // Restore the regular fill color.
    if (styleTextColor != context->fillColor())
        context->setFillColor(styleTextColor);

    if (hasShadow)
        context->clearDrawLooper();

    paintMarkupBox(paintInfo, paintOffset, lineTop, lineBottom, style);
}

AffineTransform SVGGraphicsElement::calculateAnimatedLocalTransform() const
{
    AffineTransform matrix;
    const ComputedStyle* style = layoutObject() ? layoutObject()->style() : nullptr;

    // If CSS property was set, use that, otherwise fallback to attribute (if set).
    if (style && style->hasTransform()) {
        TransformationMatrix transform;
        float zoom = style->effectiveZoom();

        // SVGTextElements need special handling for the text positioning code.
        if (isSVGTextElement(this)) {
            // Do not take into account SVG's zoom rules, transform-origin, or percentage values.
            style->applyTransform(transform, LayoutSize(0, 0), ComputedStyle::ExcludeTransformOrigin, ComputedStyle::IncludeMotionPath, ComputedStyle::IncludeIndependentTransformProperties);
        } else {
            // CSS transforms operate with pre-scaled lengths. To make this work with SVG
            // (which applies the zoom factor globally, at the root level) we
            //
            //   * pre-scale the bounding box (to bring it into the same space as the other CSS values)
            //   * invert the zoom factor (to effectively compute the CSS transform under a 1.0 zoom)
            //
            // Note: objectBoundingBox is an emptyRect for elements like pattern or clipPath.
            // See the "Object bounding box units" section of http://dev.w3.org/csswg/css3-transforms/
            if (zoom != 1) {
                FloatRect scaledBBox = layoutObject()->objectBoundingBox();
                scaledBBox.scale(zoom);
                transform.scale(1 / zoom);
                style->applyTransform(transform, scaledBBox, ComputedStyle::IncludeTransformOrigin, ComputedStyle::IncludeMotionPath, ComputedStyle::IncludeIndependentTransformProperties);
                transform.scale(zoom);
            } else {
                style->applyTransform(transform, layoutObject()->objectBoundingBox(), ComputedStyle::IncludeTransformOrigin, ComputedStyle::IncludeMotionPath, ComputedStyle::IncludeIndependentTransformProperties);
            }
        }

        // Flatten any 3D transform.
        matrix = transform.toAffineTransform();
    } else {
        m_transform->currentValue()->concatenate(matrix);
    }

    if (hasSVGRareData())
        return *svgRareData()->animateMotionTransform() * matrix;
    return matrix;
}

LayoutState::LayoutState(LayoutObject& root)
    : m_isPaginated(false)
    , m_pageLogicalHeightChanged(false)
    , m_containingBlockLogicalWidthChanged(false)
    , m_flowThread(nullptr)
    , m_next(root.view()->layoutState())
    , m_layoutObject(root)
{
    ASSERT(!m_next);
    // We'll end up pushing in LayoutView itself, so don't bother adding it.
    if (root.isLayoutView())
        return;

    root.view()->pushLayoutState(*this);

    LayoutObject* container = root.container();
    FloatPoint absContentPoint = container->localToAbsolute(FloatPoint(), UseTransforms);
    m_layoutOffset = LayoutSize(absContentPoint.x(), absContentPoint.y());
}

LayoutRect RootFrameViewport::scrollIntoView(const LayoutRect& rectInContent, const ScrollAlignment& alignX, const ScrollAlignment& alignY)
{
    // We want to move the rect into the viewport that excludes the scrollbars so we intersect
    // the visual viewport with the scrollbar-excluded frameView content rect. However, we don't
    // use visibleContentRect directly since it floors the scroll position. Instead, we use
    // FrameView::scrollPositionDouble and construct a LayoutRect from that (the FrameView size
    // is always integer sized.

    LayoutRect frameRectInContent = LayoutRect(
        layoutViewport().scrollPositionDouble(),
        layoutViewport().visibleContentRect().size());
    LayoutRect visualRectInContent = LayoutRect(
        layoutViewport().scrollPositionDouble() + toDoubleSize(visualViewport().scrollPositionDouble()),
        visualViewport().visibleContentRect().size());

    LayoutRect viewRectInContent = intersection(visualRectInContent, frameRectInContent);
    LayoutRect targetViewport =
        ScrollAlignment::getRectToExpose(viewRectInContent, rectInContent, alignX, alignY);

    // visualViewport.scrollIntoView will attempt to center the given rect within the viewport
    // so to prevent it from adjusting r's coordinates the rect must match the viewport's size
    // i.e. add the subtracted scrollbars from above back in.
    // FIXME: This is hacky and required because getRectToExpose doesn't naturally account
    // for the two viewports. crbug.com/449340.
    targetViewport.setSize(LayoutSize(visualViewport().visibleContentRect().size()));

    // Snap the visible rect to layout units to match the calculated target viewport rect.
    FloatRect visible =
        LayoutRect(visualViewport().scrollPositionDouble(), visualViewport().visibleContentRect().size());

    float centeringOffsetX = (visible.width() - targetViewport.width()) / 2;
    float centeringOffsetY = (visible.height() - targetViewport.height()) / 2;

    DoublePoint targetOffset(
        targetViewport.x() - centeringOffsetX,
        targetViewport.y() - centeringOffsetY);

    setScrollPosition(targetOffset, ProgrammaticScroll);

    // RootFrameViewport only changes the viewport relative to the document so we can't change the input
    // rect's location relative to the document origin.
    return rectInContent;
}

void TransformState::applyTransform(
    const TransformationMatrix& transformFromContainer,
    TransformAccumulation accumulate,
    bool* wasClamped) {
  if (wasClamped)
    *wasClamped = false;

  if (transformFromContainer.isIntegerTranslation()) {
    move(LayoutSize(LayoutUnit(transformFromContainer.e()),
                    LayoutUnit(transformFromContainer.f())),
         accumulate);
    return;
  }

  applyAccumulatedOffset();

  // If we have an accumulated transform from last time, multiply in this
  // transform
  if (m_accumulatedTransform) {
    if (m_direction == ApplyTransformDirection)
      m_accumulatedTransform = TransformationMatrix::create(
          transformFromContainer * *m_accumulatedTransform);
    else
      m_accumulatedTransform->multiply(transformFromContainer);
  } else if (accumulate == AccumulateTransform) {
    // Make one if we started to accumulate
    m_accumulatedTransform =
        TransformationMatrix::create(transformFromContainer);
  }

  if (accumulate == FlattenTransform) {
    if (m_forceAccumulatingTransform) {
      m_accumulatedTransform->flattenTo2d();
    } else {
      const TransformationMatrix* finalTransform =
          m_accumulatedTransform ? m_accumulatedTransform.get()
                                 : &transformFromContainer;
      flattenWithTransform(*finalTransform, wasClamped);
    }
  }
  m_accumulatingTransform =
      accumulate == AccumulateTransform || m_forceAccumulatingTransform;
}

const RenderObject* RenderView::pushMappingToContainer(const RenderBox* ancestorToStopAt, RenderGeometryMap& geometryMap) const
{
    LayoutSize offset;
    RenderObject* container = 0;

    // If a container was specified, and was not 0 or the RenderView, then we
    // should have found it by now unless we're traversing to a parent document.
    ASSERT_ARG(ancestorToStopAt, !ancestorToStopAt || ancestorToStopAt == this || container);

    if ((!ancestorToStopAt || container) && shouldUseTransformFromContainer(container)) {
        TransformationMatrix t;
        getTransformFromContainer(container, LayoutSize(), t);
        geometryMap.push(this, t, false, false, true);
    } else {
        geometryMap.push(this, offset, false, false, false);
    }

    return container;
}

PassOwnPtr<Shape> ShapeOutsideInfo::createShapeForImage(StyleImage* styleImage, float shapeImageThreshold, WritingMode writingMode, float margin) const
{
    const IntSize& imageSize = m_layoutBox.calculateImageIntrinsicDimensions(styleImage, roundedIntSize(m_referenceBoxLogicalSize), LayoutImage::ScaleByEffectiveZoom);
    styleImage->setContainerSizeForLayoutObject(&m_layoutBox, imageSize, m_layoutBox.style()->effectiveZoom());

    const LayoutRect& marginRect = getShapeImageMarginRect(m_layoutBox, m_referenceBoxLogicalSize);
    const LayoutRect& imageRect = (m_layoutBox.isLayoutImage())
        ? toLayoutImage(m_layoutBox).replacedContentRect()
        : LayoutRect(LayoutPoint(), LayoutSize(imageSize));

    if (!isValidRasterShapeRect(marginRect) || !isValidRasterShapeRect(imageRect)) {
        m_layoutBox.document().addConsoleMessage(ConsoleMessage::create(RenderingMessageSource, ErrorMessageLevel, "The shape-outside image is too large."));
        return Shape::createEmptyRasterShape(writingMode, margin);
    }

    ASSERT(!styleImage->isPendingImage());
    RefPtr<Image> image = styleImage->image(const_cast<LayoutBox*>(&m_layoutBox), imageSize);

    return Shape::createRasterShape(image.get(), shapeImageThreshold, imageRect, marginRect, writingMode, margin);
}

void EllipsisBoxPainter::paintEllipsis(const PaintInfo& paintInfo, const LayoutPoint& paintOffset, LayoutUnit lineTop, LayoutUnit lineBottom, const ComputedStyle& style)
{
    bool haveSelection = !paintInfo.isPrinting() && paintInfo.phase != PaintPhaseTextClip && m_ellipsisBox.getSelectionState() != SelectionNone;

    LayoutRect paintRect(m_ellipsisBox.logicalFrameRect());
    if (haveSelection)
        paintRect.unite(LayoutRect(m_ellipsisBox.selectionRect()));
    m_ellipsisBox.logicalRectToPhysicalRect(paintRect);
    paintRect.moveBy(paintOffset);

    GraphicsContext& context = paintInfo.context;
    DisplayItem::Type displayItemType = DisplayItem::paintPhaseToDrawingType(paintInfo.phase);
    if (DrawingRecorder::useCachedDrawingIfPossible(context, m_ellipsisBox, displayItemType))
        return;

    DrawingRecorder recorder(context, m_ellipsisBox, displayItemType, FloatRect(paintRect));

    LayoutPoint boxOrigin = m_ellipsisBox.locationIncludingFlipping();
    boxOrigin.moveBy(paintOffset);
    LayoutRect boxRect(boxOrigin, LayoutSize(m_ellipsisBox.logicalWidth(), m_ellipsisBox.virtualLogicalHeight()));

    GraphicsContextStateSaver stateSaver(context);
    if (!m_ellipsisBox.isHorizontal())
        context.concatCTM(TextPainter::rotation(boxRect, TextPainter::Clockwise));

    const Font& font = style.font();

    if (haveSelection)
        paintSelection(context, boxOrigin, style, font);
    else if (paintInfo.phase == PaintPhaseSelection)
        return;

    TextPainter::Style textStyle = TextPainter::textPaintingStyle(m_ellipsisBox.getLineLayoutItem(), style, paintInfo);
    if (haveSelection)
        textStyle = TextPainter::selectionPaintingStyle(m_ellipsisBox.getLineLayoutItem(), true, paintInfo, textStyle);

    TextRun textRun = constructTextRun(font, m_ellipsisBox.ellipsisStr(), style, TextRun::AllowTrailingExpansion);
    LayoutPoint textOrigin(boxOrigin.x(), boxOrigin.y() + font.getFontMetrics().ascent());
    TextPainter textPainter(context, font, textRun, textOrigin, boxRect, m_ellipsisBox.isHorizontal());
    textPainter.paint(0, m_ellipsisBox.ellipsisStr().length(), m_ellipsisBox.ellipsisStr().length(), textStyle);
}

VisiblePosition LocalFrame::visiblePositionForPoint(const IntPoint& framePoint)
{
    if (!contentRenderer() || !view() || !view()->didFirstLayout())
      return VisiblePosition();

    LayoutSize padding = LayoutSize();
    HitTestResult result(framePoint, padding.height(), padding.width(), padding.height(), padding.width());
    HitTestRequest request(HitTestRequest::ReadOnly | HitTestRequest::Active);
    contentRenderer()->hitTest(request, result);

    Node* node = result.innerNonSharedNode();
    if (!node)
        return VisiblePosition();
    RenderObject* renderer = node->renderer();
    if (!renderer)
        return VisiblePosition();
    VisiblePosition visiblePos = VisiblePosition(renderer->positionForPoint(result.localPoint()));
    if (visiblePos.isNull())
        visiblePos = VisiblePosition(firstPositionInOrBeforeNode(node));
    return visiblePos;
}