C++ LayoutRect::shiftYEdgeTo方法代码示例

LayoutRect RenderRegion::rectFlowPortionForBox(const RenderBox* box, const LayoutRect& rect) const
{
    RenderRegion* startRegion = 0;
    RenderRegion* endRegion = 0;
    m_flowThread->getRegionRangeForBox(box, startRegion, endRegion);

    LayoutRect mappedRect = m_flowThread->mapFromLocalToFlowThread(box, rect);
    if (flowThread()->isHorizontalWritingMode()) {
        if (this != startRegion)
            mappedRect.shiftYEdgeTo(std::max<LayoutUnit>(logicalTopForFlowThreadContent(), mappedRect.y()));

        if (this != endRegion)
            mappedRect.setHeight(std::max<LayoutUnit>(0, std::min<LayoutUnit>(logicalBottomForFlowThreadContent() - mappedRect.y(), mappedRect.height())));
    } else {
        if (this != startRegion)
            mappedRect.shiftXEdgeTo(std::max<LayoutUnit>(logicalTopForFlowThreadContent(), mappedRect.x()));
            
        if (this != endRegion)
            mappedRect.setWidth(std::max<LayoutUnit>(0, std::min<LayoutUnit>(logicalBottomForFlowThreadContent() - mappedRect.x(), mappedRect.width())));
    }

    if (shouldClipFlowThreadContent()) {
        LayoutRect portionRect;
        if (isRenderNamedFlowFragment())
            portionRect = toRenderNamedFlowFragment(this)->flowThreadPortionRectForClipping(this == startRegion, this == endRegion);
        else
            portionRect = flowThreadPortionRect();
        
        mappedRect.intersect(portionRect);
    }

    return mappedRect.isEmpty() ? mappedRect : m_flowThread->mapFromFlowThreadToLocal(box, mappedRect);
}

LayoutRect RenderRegion::rectFlowPortionForBox(const RenderBox* box, const LayoutRect& rect) const
{
    RenderRegion* startRegion = 0;
    RenderRegion* endRegion = 0;
    m_flowThread->getRegionRangeForBox(box, startRegion, endRegion);

    LayoutRect mappedRect = m_flowThread->mapFromLocalToFlowThread(box, rect);
    if (flowThread()->isHorizontalWritingMode()) {
        if (this != startRegion)
            mappedRect.shiftYEdgeTo(std::max<LayoutUnit>(logicalTopForFlowThreadContent(), mappedRect.y()));

        if (this != endRegion)
            mappedRect.setHeight(std::max<LayoutUnit>(0, std::min<LayoutUnit>(logicalBottomForFlowThreadContent() - mappedRect.y(), mappedRect.height())));
    } else {
        if (this != startRegion)
            mappedRect.shiftXEdgeTo(std::max<LayoutUnit>(logicalTopForFlowThreadContent(), mappedRect.x()));
            
        if (this != endRegion)
            mappedRect.setWidth(std::max<LayoutUnit>(0, std::min<LayoutUnit>(logicalBottomForFlowThreadContent() - mappedRect.x(), mappedRect.width())));
    }

    bool isLastRegionWithRegionFragmentBreak = (isLastRegion() && (style().regionFragment() == BreakRegionFragment));
    if (hasOverflowClip() || isLastRegionWithRegionFragmentBreak)
        mappedRect.intersect(flowThreadPortionRect());

    return mappedRect.isEmpty() ? mappedRect : m_flowThread->mapFromFlowThreadToLocal(box, mappedRect);
}

void RenderLineBreak::collectSelectionRects(Vector<SelectionRect>& rects, unsigned, unsigned)
{
    ensureLineBoxes(*this);
    InlineElementBox* box = m_inlineBoxWrapper;
    if (!box)
        return;
    const RootInlineBox& rootBox = box->root();
    LayoutRect rect = rootBox.computeCaretRect(box->logicalLeft(), 0, nullptr);
    if (rootBox.isFirstAfterPageBreak()) {
        if (box->isHorizontal())
            rect.shiftYEdgeTo(rootBox.lineTopWithLeading());
        else
            rect.shiftXEdgeTo(rootBox.lineTopWithLeading());
    }

    RenderBlock* containingBlock = this->containingBlock();
    // Map rect, extended left to leftOffset, and right to rightOffset, through transforms to get minX and maxX.
    LogicalSelectionOffsetCaches cache(*containingBlock);
    LayoutUnit leftOffset = containingBlock->logicalLeftSelectionOffset(*containingBlock, box->logicalTop(), cache);
    LayoutUnit rightOffset = containingBlock->logicalRightSelectionOffset(*containingBlock, box->logicalTop(), cache);
    LayoutRect extentsRect = rect;
    if (box->isHorizontal()) {
        extentsRect.setX(leftOffset);
        extentsRect.setWidth(rightOffset - leftOffset);
    } else {
        extentsRect.setY(leftOffset);
        extentsRect.setHeight(rightOffset - leftOffset);
    }
    extentsRect = localToAbsoluteQuad(FloatRect(extentsRect)).enclosingBoundingBox();
    if (!box->isHorizontal())
        extentsRect = extentsRect.transposedRect();
    bool isFirstOnLine = !box->previousOnLineExists();
    bool isLastOnLine = !box->nextOnLineExists();
    if (containingBlock->isRubyBase() || containingBlock->isRubyText())
        isLastOnLine = !containingBlock->containingBlock()->inlineBoxWrapper()->nextOnLineExists();

    bool isFixed = false;
    IntRect absRect = localToAbsoluteQuad(FloatRect(rect), UseTransforms, &isFixed).enclosingBoundingBox();
    bool boxIsHorizontal = !box->isSVGInlineTextBox() ? box->isHorizontal() : !style().svgStyle().isVerticalWritingMode();
    // If the containing block is an inline element, we want to check the inlineBoxWrapper orientation
    // to determine the orientation of the block. In this case we also use the inlineBoxWrapper to
    // determine if the element is the last on the line.
    if (containingBlock->inlineBoxWrapper()) {
        if (containingBlock->inlineBoxWrapper()->isHorizontal() != boxIsHorizontal) {
            boxIsHorizontal = containingBlock->inlineBoxWrapper()->isHorizontal();
            isLastOnLine = !containingBlock->inlineBoxWrapper()->nextOnLineExists();
        }
    }

    rects.append(SelectionRect(absRect, box->direction(), extentsRect.x(), extentsRect.maxX(), extentsRect.maxY(), 0, box->isLineBreak(), isFirstOnLine, isLastOnLine, false, false, boxIsHorizontal, isFixed, containingBlock->isRubyText(), view().pageNumberForBlockProgressionOffset(absRect.x())));
}

LayoutRect MultiColumnFragmentainerGroup::flowThreadPortionOverflowRectAt(
    unsigned columnIndex) const {
  // This function determines the portion of the flow thread that paints for the
  // column. Along the inline axis, columns are unclipped at outside edges
  // (i.e., the first and last column in the set), and they clip to half the
  // column gap along interior edges.
  //
  // In the block direction, we will not clip overflow out of the top of the
  // first column, or out of the bottom of the last column. This applies only to
  // the true first column and last column across all column sets.
  //
  // FIXME: Eventually we will know overflow on a per-column basis, but we can't
  // do this until we have a painting mode that understands not to paint
  // contents from a previous column in the overflow area of a following column.
  bool isFirstColumnInRow = !columnIndex;
  bool isLastColumnInRow = columnIndex == actualColumnCount() - 1;
  bool isLTR = m_columnSet.style()->isLeftToRightDirection();
  bool isLeftmostColumn = isLTR ? isFirstColumnInRow : isLastColumnInRow;
  bool isRightmostColumn = isLTR ? isLastColumnInRow : isFirstColumnInRow;

  LayoutRect portionRect = flowThreadPortionRectAt(columnIndex);
  bool isFirstColumnInMulticolContainer =
      isFirstColumnInRow && this == &m_columnSet.firstFragmentainerGroup() &&
      !m_columnSet.previousSiblingMultiColumnSet();
  bool isLastColumnInMulticolContainer =
      isLastColumnInRow && this == &m_columnSet.lastFragmentainerGroup() &&
      !m_columnSet.nextSiblingMultiColumnSet();
  // Calculate the overflow rectangle, based on the flow thread's, clipped at
  // column logical top/bottom unless it's the first/last column.
  LayoutRect overflowRect = m_columnSet.overflowRectForFlowThreadPortion(
      portionRect, isFirstColumnInMulticolContainer,
      isLastColumnInMulticolContainer);

  // Avoid overflowing into neighboring columns, by clipping in the middle of
  // adjacent column gaps. Also make sure that we avoid rounding errors.
  LayoutUnit columnGap = m_columnSet.columnGap();
  if (m_columnSet.isHorizontalWritingMode()) {
    if (!isLeftmostColumn)
      overflowRect.shiftXEdgeTo(portionRect.x() - columnGap / 2);
    if (!isRightmostColumn)
      overflowRect.shiftMaxXEdgeTo(portionRect.maxX() + columnGap -
                                   columnGap / 2);
  } else {
    if (!isLeftmostColumn)
      overflowRect.shiftYEdgeTo(portionRect.y() - columnGap / 2);
    if (!isRightmostColumn)
      overflowRect.shiftMaxYEdgeTo(portionRect.maxY() + columnGap -
                                   columnGap / 2);
  }
  return overflowRect;
}

LayoutRect RootInlineBox::paddedLayoutOverflowRect(LayoutUnit endPadding) const
{
    LayoutRect lineLayoutOverflow = layoutOverflowRect(lineTop(), lineBottom());
    if (!endPadding)
        return lineLayoutOverflow;
    
    // FIXME: Audit whether to use pixel snapped values when not using integers for layout: https://bugs.webkit.org/show_bug.cgi?id=63656
    if (isHorizontal()) {
        if (isLeftToRightDirection())
            lineLayoutOverflow.shiftMaxXEdgeTo(std::max<LayoutUnit>(lineLayoutOverflow.maxX(), pixelSnappedLogicalRight() + endPadding));
        else
            lineLayoutOverflow.shiftXEdgeTo(std::min<LayoutUnit>(lineLayoutOverflow.x(), pixelSnappedLogicalLeft() - endPadding));
    } else {
        if (isLeftToRightDirection())
            lineLayoutOverflow.shiftMaxYEdgeTo(std::max<LayoutUnit>(lineLayoutOverflow.maxY(), pixelSnappedLogicalRight() + endPadding));
        else
            lineLayoutOverflow.shiftYEdgeTo(std::min<LayoutUnit>(lineLayoutOverflow.y(), pixelSnappedLogicalLeft() - endPadding));
    }
    
    return lineLayoutOverflow;
}

LayoutRect RenderMultiColumnSet::flowThreadPortionOverflowRect(const LayoutRect& portionRect, unsigned index, unsigned colCount, LayoutUnit colGap)
{
    // This function determines the portion of the flow thread that paints for the column. Along the inline axis, columns are
    // unclipped at outside edges (i.e., the first and last column in the set), and they clip to half the column
    // gap along interior edges.
    //
    // In the block direction, we will not clip overflow out of the top of the first column, or out of the bottom of
    // the last column. This applies only to the true first column and last column across all column sets.
    //
    // FIXME: Eventually we will know overflow on a per-column basis, but we can't do this until we have a painting
    // mode that understands not to paint contents from a previous column in the overflow area of a following column.
    // This problem applies to regions and pages as well and is not unique to columns.
    
    RenderBlockFlow* parentFlow = toRenderBlockFlow(parent());
    bool progressionReversed = parentFlow->multiColumnFlowThread()->progressionIsReversed();
    
    bool isFirstColumn = !index;
    bool isLastColumn = index == colCount - 1;
    bool isLeftmostColumn = style().isLeftToRightDirection() ^ progressionReversed ? isFirstColumn : isLastColumn;
    bool isRightmostColumn = style().isLeftToRightDirection() ^ progressionReversed ? isLastColumn : isFirstColumn;

    // Calculate the overflow rectangle, based on the flow thread's, clipped at column logical
    // top/bottom unless it's the first/last column.
    LayoutRect overflowRect = overflowRectForFlowThreadPortion(portionRect, isFirstColumn && isFirstRegion(), isLastColumn && isLastRegion(), VisualOverflow);

    // Avoid overflowing into neighboring columns, by clipping in the middle of adjacent column
    // gaps. Also make sure that we avoid rounding errors.
    if (isHorizontalWritingMode()) {
        if (!isLeftmostColumn)
            overflowRect.shiftXEdgeTo(portionRect.x() - colGap / 2);
        if (!isRightmostColumn)
            overflowRect.shiftMaxXEdgeTo(portionRect.maxX() + colGap - colGap / 2);
    } else {
        if (!isLeftmostColumn)
            overflowRect.shiftYEdgeTo(portionRect.y() - colGap / 2);
        if (!isRightmostColumn)
            overflowRect.shiftMaxYEdgeTo(portionRect.maxY() + colGap - colGap / 2);
    }
    return overflowRect;
}

void RenderMathMLOperator::fillWithExtensionGlyph(PaintInfo& info, const LayoutPoint& from, const LayoutPoint& to)
{
    ASSERT(m_stretchyCharacter);
    ASSERT(m_stretchyCharacter->extensionGlyph);
    ASSERT(from.y() <= to.y());

    // If there is no space for the extension glyph, we don't need to do anything.
    if (from.y() == to.y())
        return;

    GraphicsContextStateSaver stateSaver(*info.context);

    FloatRect glyphBounds = glyphBoundsForCharacter(m_stretchyCharacter->extensionGlyph);

    // Clipping the extender region here allows us to draw the bottom extender glyph into the
    // regions of the bottom glyph without worrying about overdraw (hairy pixels) and simplifies later clipping.
    LayoutRect clipBounds = info.rect;
    clipBounds.shiftYEdgeTo(from.y());
    clipBounds.shiftMaxYEdgeTo(to.y());
    info.context->clip(clipBounds);

    // Trimming may remove up to two pixels from the top of the extender glyph, so we move it up by two pixels.
    float offsetToGlyphTop = glyphBounds.y() + 2;
    LayoutPoint glyphOrigin = LayoutPoint(from.x(), from.y() - offsetToGlyphTop);
    FloatRect lastPaintedGlyphRect(from, FloatSize());

    while (lastPaintedGlyphRect.maxY() < to.y()) {
        lastPaintedGlyphRect = paintCharacter(info, m_stretchyCharacter->extensionGlyph, glyphOrigin, TrimTopAndBottom);
        glyphOrigin.setY(glyphOrigin.y() + lastPaintedGlyphRect.height());

        // There's a chance that if the font size is small enough the glue glyph has been reduced to an empty rectangle
        // with trimming. In that case we just draw nothing.
        if (lastPaintedGlyphRect.isEmpty())
            break;
    }
}

LayoutRect RenderNamedFlowThread::decorationsClipRectForBoxInNamedFlowFragment(const RenderBox& box, RenderNamedFlowFragment& fragment) const
{
    LayoutRect visualOverflowRect = fragment.visualOverflowRectForBox(&box);
    LayoutUnit initialLogicalX = style().isHorizontalWritingMode() ? visualOverflowRect.x() : visualOverflowRect.y();

    // The visual overflow rect returned by visualOverflowRectForBox is already flipped but the
    // RenderRegion::rectFlowPortionForBox method expects it unflipped.
    flipForWritingModeLocalCoordinates(visualOverflowRect);
    visualOverflowRect = fragment.rectFlowPortionForBox(&box, visualOverflowRect);
    
    // Now flip it again.
    flipForWritingModeLocalCoordinates(visualOverflowRect);

    // Take the scrolled offset of this object's parents into consideration.
    IntSize scrolledContentOffset;
    RenderBlock* containingBlock = box.containingBlock();
    while (containingBlock) {
        if (containingBlock->isRenderNamedFlowThread()) {
            // We've reached the flow thread, take the scrolled offset of the region into consideration.
            ASSERT(containingBlock == this);
            scrolledContentOffset += fragment.fragmentContainer().scrolledContentOffset();
            break;
        }
        
        scrolledContentOffset += containingBlock->scrolledContentOffset();
        containingBlock = containingBlock->containingBlock();
    }

    if (!scrolledContentOffset.isZero()) {
        if (style().isFlippedBlocksWritingMode())
            scrolledContentOffset = -scrolledContentOffset;
        
        visualOverflowRect.inflateX(scrolledContentOffset.width());
        visualOverflowRect.inflateY(scrolledContentOffset.height());
    }
    
    // Layers are in physical coordinates so the origin must be moved to the physical top-left of the flowthread.
    if (style().isFlippedBlocksWritingMode()) {
        if (style().isHorizontalWritingMode())
            visualOverflowRect.moveBy(LayoutPoint(0, height()));
        else
            visualOverflowRect.moveBy(LayoutPoint(width(), 0));
    }

    const RenderBox* iterBox = &box;
    while (iterBox && iterBox != this) {
        RenderBlock* containerBlock = iterBox->containingBlock();

        // FIXME: This doesn't work properly with flipped writing modes.
        // https://bugs.webkit.org/show_bug.cgi?id=125149
        if (iterBox->isPositioned()) {
            // For positioned elements, just use the layer's absolute bounding box.
            visualOverflowRect.moveBy(iterBox->layer()->absoluteBoundingBox().location());
            break;
        }

        LayoutRect currentBoxRect = iterBox->frameRect();
        if (iterBox->style().isFlippedBlocksWritingMode()) {
            if (iterBox->style().isHorizontalWritingMode())
                currentBoxRect.setY(currentBoxRect.height() - currentBoxRect.maxY());
            else
                currentBoxRect.setX(currentBoxRect.width() - currentBoxRect.maxX());
        }

        if (containerBlock->style().writingMode() != iterBox->style().writingMode())
            iterBox->flipForWritingMode(currentBoxRect);

        visualOverflowRect.moveBy(currentBoxRect.location());
        iterBox = containerBlock;
    }

    // Since the purpose of this method is to make sure the borders of a fragmented
    // element don't overflow the region in the fragmentation direction, there's no
    // point in restricting the clipping rect on the logical X axis. 
    // This also saves us the trouble of handling percent-based widths and margins
    // since the absolute bounding box of a positioned element would not contain
    // the correct coordinates relative to the region we're interested in, but rather
    // relative to the actual flow thread.
    if (style().isHorizontalWritingMode()) {
        if (initialLogicalX < visualOverflowRect.x())
            visualOverflowRect.shiftXEdgeTo(initialLogicalX);
        if (visualOverflowRect.width() < frameRect().width())
            visualOverflowRect.setWidth(frameRect().width());
    } else {
        if (initialLogicalX < visualOverflowRect.y())
            visualOverflowRect.shiftYEdgeTo(initialLogicalX);
        if (visualOverflowRect.height() < frameRect().height())
            visualOverflowRect.setHeight(frameRect().height());
    }

    return visualOverflowRect;
}