C++ LayoutObject::isLayoutInline方法代码示例

static LayoutObject* getParentOfFirstLineBox(LayoutBlockFlow* curr, LayoutObject* marker)
{
    LayoutObject* firstChild = curr->firstChild();
    if (!firstChild)
        return nullptr;

    bool inQuirksMode = curr->document().inQuirksMode();
    for (LayoutObject* currChild = firstChild; currChild; currChild = currChild->nextSibling()) {
        if (currChild == marker)
            continue;

        if (currChild->isInline() && (!currChild->isLayoutInline() || curr->generatesLineBoxesForInlineChild(currChild)))
            return curr;

        if (currChild->isFloating() || currChild->isOutOfFlowPositioned())
            continue;

        if (!currChild->isLayoutBlockFlow() || (currChild->isBox() && toLayoutBox(currChild)->isWritingModeRoot()))
            break;

        if (curr->isListItem() && inQuirksMode && currChild->node()
            && (isHTMLUListElement(*currChild->node()) || isHTMLOListElement(*currChild->node())))
            break;

        LayoutObject* lineBox = getParentOfFirstLineBox(toLayoutBlockFlow(currChild), marker);
        if (lineBox)
            return lineBox;
    }

    return nullptr;
}

bool Text::textLayoutObjectIsNeeded(const ComputedStyle& style, const LayoutObject& parent)
{
    if (!parent.canHaveChildren())
        return false;

    if (isEditingText())
        return true;

    if (!length())
        return false;

    if (style.display() == NONE)
        return false;

    if (!containsOnlyWhitespace())
        return true;

    if (!canHaveWhitespaceChildren(parent, this))
        return false;

    // pre-wrap in SVG never makes layoutObject.
    if (style.whiteSpace() == PRE_WRAP && parent.isSVG())
        return false;

    // pre/pre-wrap/-bb-pre-wrap-text/pre-line always make layoutObjects.
    if (style.preserveNewline())
        return true;

    // childNeedsDistributionRecalc() here is rare, only happens JS calling surroundContents() etc. from DOMNodeInsertedIntoDocument etc.
    if (document().childNeedsDistributionRecalc())
        return true;

    const LayoutObject* prev = LayoutTreeBuilderTraversal::previousSiblingLayoutObject(*this);
    if (prev && prev->isBR()) // <span><br/> <br/></span>
        return false;

    if (parent.isLayoutInline()) {
        // <span><div/> <div/></span>
        if (prev && !prev->isInline() && !prev->isOutOfFlowPositioned())
            return false;
    } else {
        if (parent.isLayoutBlock() && !parent.childrenInline() && (!prev || !prev->isInline()))
            return false;

        // Avoiding creation of a layoutObject for the text node is a non-essential memory optimization.
        // So to avoid blowing up on very wide DOMs, we limit the number of siblings to visit.
        unsigned maxSiblingsToVisit = 50;

        LayoutObject* first = parent.slowFirstChild();
        while (first && first->isFloatingOrOutOfFlowPositioned() && maxSiblingsToVisit--)
            first = first->nextSibling();
        if (!first || first == layoutObject() || LayoutTreeBuilderTraversal::nextSiblingLayoutObject(*this) == first) {
            // Whitespace at the start of a block just goes away.  Don't even
            // make a layout object for this text.
            return false;
        }
    }
    return true;
}

void LayoutAnalyzer::push(const LayoutObject& o)
{
    increment(TotalLayoutObjectsThatWereLaidOut);
    if (!o.everHadLayout())
        increment(LayoutObjectsThatHadNeverHadLayout);
    if (o.selfNeedsLayout())
        increment(LayoutObjectsThatNeedLayoutForThemselves);
    if (o.needsPositionedMovementLayout())
        increment(LayoutObjectsThatNeedPositionedMovementLayout);
    if (o.isOutOfFlowPositioned())
        increment(LayoutObjectsThatAreOutOfFlowPositioned);
    if (o.isTableCell())
        increment(LayoutObjectsThatAreTableCells);
    if (o.isFloating())
        increment(LayoutObjectsThatAreFloating);
    if (o.style()->specifiesColumns())
        increment(LayoutObjectsThatSpecifyColumns);
    if (o.hasLayer())
        increment(LayoutObjectsThatHaveALayer);
    if (o.isLayoutInline() && o.alwaysCreateLineBoxesForLayoutInline())
        increment(LayoutInlineObjectsThatAlwaysCreateLineBoxes);
    if (o.isText()) {
        const LayoutText& t = *toLayoutText(&o);
        if (t.canUseSimpleFontCodePath()) {
            increment(LayoutObjectsThatAreTextAndCanUseTheSimpleFontCodePath);
            increment(CharactersInLayoutObjectsThatAreTextAndCanUseTheSimpleFontCodePath, t.textLength());
        } else {
            increment(LayoutObjectsThatAreTextAndCanNotUseTheSimpleFontCodePath);
            increment(CharactersInLayoutObjectsThatAreTextAndCanNotUseTheSimpleFontCodePath, t.textLength());
        }
    }

    // This might be a root in a subtree layout, in which case the LayoutObject
    // has a parent but the stack is empty. If a LayoutObject subclass forgets
    // to call push() and is a root in a subtree layout, then this
    // assert would only fail if that LayoutObject instance has any children
    // that need layout and do call push().
    // LayoutBlock::layoutPositionedObjects() hoists positioned descendants.
    // LayoutBlockFlow::layoutInlineChildren() walks through inlines.
    // LayoutTableSection::layoutRows() walks through rows.
    if (!o.isPositioned()
        && !o.isTableCell()
        && !o.isSVGResourceContainer()
        && (m_stack.size() != 0)
        && !(o.parent()->childrenInline()
            && (o.isReplaced() || o.isFloating() || o.isOutOfFlowPositioned()))) {
        ASSERT(o.parent() == m_stack.peek());
    }
    m_stack.push(&o);

    // This refers to LayoutAnalyzer depth, not layout tree depth or DOM tree
    // depth. LayoutAnalyzer depth is generally closer to C++ stack recursion
    // depth. See above exceptions for when LayoutAnalyzer depth != layout tree
    // depth.
    if (m_stack.size() > m_counters[LayoutAnalyzerStackMaximumDepth])
        m_counters[LayoutAnalyzerStackMaximumDepth] = m_stack.size();

}

float TextAutosizer::inflate(LayoutObject* parent, InflateBehavior behavior, float multiplier)
{
    Cluster* cluster = currentCluster();
    bool hasTextChild = false;

    LayoutObject* child = nullptr;
    if (parent->isLayoutBlock() && (parent->childrenInline() || behavior == DescendToInnerBlocks))
        child = toLayoutBlock(parent)->firstChild();
    else if (parent->isLayoutInline())
        child = toLayoutInline(parent)->firstChild();

    while (child) {
        if (child->isText()) {
            hasTextChild = true;
            // We only calculate this multiplier on-demand to ensure the parent block of this text
            // has entered layout.
            if (!multiplier)
                multiplier = cluster->m_flags & SUPPRESSING ? 1.0f : clusterMultiplier(cluster);
            applyMultiplier(child, multiplier);

            // FIXME: Investigate why MarkOnlyThis is sufficient.
            if (parent->isLayoutInline())
                child->setPreferredLogicalWidthsDirty(MarkOnlyThis);
        } else if (child->isLayoutInline()) {
            multiplier = inflate(child, behavior, multiplier);
        } else if (child->isLayoutBlock() && behavior == DescendToInnerBlocks
            && !classifyBlock(child, INDEPENDENT | EXPLICIT_WIDTH | SUPPRESSING)) {
            multiplier = inflate(child, behavior, multiplier);
        }
        child = child->nextSibling();
    }

    if (hasTextChild) {
        applyMultiplier(parent, multiplier); // Parent handles line spacing.
    } else if (!parent->isListItem()) {
        // For consistency, a block with no immediate text child should always have a
        // multiplier of 1.
        applyMultiplier(parent, 1);
    }

    if (parent->isListItem()) {
        float multiplier = clusterMultiplier(cluster);
        applyMultiplier(parent, multiplier);

        // The list item has to be treated special because we can have a tree such that you have
        // a list item for a form inside it. The list marker then ends up inside the form and when
        // we try to get the clusterMultiplier we have the wrong cluster root to work from and get
        // the wrong value.
        LayoutListItem* item = toLayoutListItem(parent);
        if (LayoutListMarker* marker = item->marker()) {
            applyMultiplier(marker, multiplier);
            marker->setPreferredLogicalWidthsDirty(MarkOnlyThis);
        }
    }

    return multiplier;
}

static void addPDFURLRectsForInlineChildrenRecursively(const LayoutObject& layoutObject, const PaintInfo& paintInfo, const LayoutPoint& paintOffset)
{
    for (LayoutObject* child = layoutObject.slowFirstChild(); child; child = child->nextSibling()) {
        if (!child->isLayoutInline() || toLayoutBoxModelObject(child)->hasSelfPaintingLayer())
            continue;
        ObjectPainter(*child).addPDFURLRectIfNeeded(paintInfo, paintOffset);
        addPDFURLRectsForInlineChildrenRecursively(*child, paintInfo, paintOffset);
    }
}

TracedLayoutObject::TracedLayoutObject(const LayoutObject& object)
    : m_address((unsigned long) &object)
    , m_isAnonymous(object.isAnonymous())
    , m_isPositioned(object.isOutOfFlowPositioned())
    , m_isRelPositioned(object.isRelPositioned())
    , m_isStickyPositioned(object.isStickyPositioned())
    , m_isFloating(object.isFloating())
    , m_selfNeeds(object.selfNeedsLayout())
    , m_positionedMovement(object.needsPositionedMovementLayout())
    , m_childNeeds(object.normalChildNeedsLayout())
    , m_posChildNeeds(object.posChildNeedsLayout())
    , m_isTableCell(object.isTableCell())
    , m_name(String(object.name()).isolatedCopy())
    , m_absRect(object.absoluteBoundingBoxRect())
{
    if (Node* node = object.node()) {
        m_tag = String(node->nodeName()).isolatedCopy();
        if (node->isElementNode()) {
            Element& element = toElement(*node);
            if (element.hasID())
                m_id = String(element.getIdAttribute()).isolatedCopy();
            if (element.hasClass()) {
                for (size_t i = 0; i < element.classNames().size(); ++i) {
                    m_classNames.append(
                        String(element.classNames()[i]).isolatedCopy());
                }
            }
        }
    }

    // FIXME: When the fixmes in LayoutTreeAsText::writeLayoutObject() are
    // fixed, deduplicate it with this.
    if (object.isText()) {
        m_rect = LayoutRect(toLayoutText(object).linesBoundingBox());
    } else if (object.isLayoutInline()) {
        m_rect = LayoutRect(toLayoutInline(object).linesBoundingBox());
    } else if (object.isBox()) {
        m_rect = toLayoutBox(&object)->frameRect();
    }

    if (m_isTableCell) {
        const LayoutTableCell& c = toLayoutTableCell(object);
        if (c.row() && c.row()->rowIndexWasSet() && c.hasCol()
            && (!c.row()->section() || !c.row()->section()->needsCellRecalc())) {
            m_row = c.rowIndex();
            m_col = c.col();
            m_rowSpan = c.rowSpan();
            m_colSpan = c.colSpan();
        }
    }

    for (LayoutObject* child = object.slowFirstChild(); child; child = child->nextSibling()) {
        m_children.append(adoptRef(new TracedLayoutObject(*child)));
    }
}

void LinkHighlight::computeQuads(const Node& node, Vector<FloatQuad>& outQuads) const
{
    if (!node.layoutObject())
        return;

    LayoutObject* renderer = node.layoutObject();

    // For inline elements, absoluteQuads will return a line box based on the line-height
    // and font metrics, which is technically incorrect as replaced elements like images
    // should use their intristic height and expand the linebox  as needed. To get an
    // appropriately sized highlight we descend into the children and have them add their
    // boxes.
    if (renderer->isLayoutInline()) {
        for (Node* child = NodeRenderingTraversal::firstChild(node); child; child = NodeRenderingTraversal::nextSibling(*child))
            computeQuads(*child, outQuads);
    } else {
        // FIXME: this does not need to be absolute, just in the paint invalidation container's space.
        renderer->absoluteQuads(outQuads);
    }
}

void LayoutAnalyzer::push(const LayoutObject& o)
{
    increment(TotalLayoutObjectsThatWereLaidOut);
    if (!o.everHadLayout())
        increment(LayoutObjectsThatHadNeverHadLayout);
    if (o.selfNeedsLayout())
        increment(LayoutObjectsThatNeedLayoutForThemselves);
    if (o.needsPositionedMovementLayout())
        increment(LayoutObjectsThatNeedPositionedMovementLayout);
    if (o.isOutOfFlowPositioned())
        increment(LayoutObjectsThatAreOutOfFlowPositioned);
    if (o.isTableCell())
        increment(LayoutObjectsThatAreTableCells);
    if (o.isFloating())
        increment(LayoutObjectsThatAreFloating);
    if (o.style()->specifiesColumns())
        increment(LayoutObjectsThatSpecifyColumns);
    if (o.hasLayer())
        increment(LayoutObjectsThatHaveALayer);
    if (o.isLayoutInline() && o.alwaysCreateLineBoxesForLayoutInline())
        increment(LayoutInlineObjectsThatAlwaysCreateLineBoxes);
    if (o.isText()) {
        const LayoutText& t = *toLayoutText(&o);
        if (t.canUseSimpleFontCodePath()) {
            increment(LayoutObjectsThatAreTextAndCanUseTheSimpleFontCodePath);
            increment(CharactersInLayoutObjectsThatAreTextAndCanUseTheSimpleFontCodePath, t.textLength());
        } else {
            increment(LayoutObjectsThatAreTextAndCanNotUseTheSimpleFontCodePath);
            increment(CharactersInLayoutObjectsThatAreTextAndCanNotUseTheSimpleFontCodePath, t.textLength());
        }
    }

    ++m_depth;

    // This refers to LayoutAnalyzer depth, which is generally closer to C++
    // stack recursion depth, not layout tree depth or DOM tree depth.
    m_counters[LayoutAnalyzerStackMaximumDepth] = max(m_counters[LayoutAnalyzerStackMaximumDepth], m_depth);
}

void LineBoxList::dirtyLinesFromChangedChild(LayoutObject* container, LayoutObject* child)
{
    if (!container->parent() || (container->isLayoutBlock() && (container->selfNeedsLayout() || !container->isLayoutBlockFlow())))
        return;

    LayoutInline* inlineContainer = container->isLayoutInline() ? toLayoutInline(container) : 0;
    InlineBox* firstBox = inlineContainer ? inlineContainer->firstLineBoxIncludingCulling() : firstLineBox();

    // If we have no first line box, then just bail early.
    if (!firstBox) {
        // For an empty inline, go ahead and propagate the check up to our parent, unless the parent
        // is already dirty.
        if (container->isInline() && !container->ancestorLineBoxDirty()) {
            container->parent()->dirtyLinesFromChangedChild(container);
            container->setAncestorLineBoxDirty(); // Mark the container to avoid dirtying the same lines again across multiple destroy() calls of the same subtree.
        }
        return;
    }

    // Try to figure out which line box we belong in.  First try to find a previous
    // line box by examining our siblings.  If we didn't find a line box, then use our
    // parent's first line box.
    RootInlineBox* box = 0;
    LayoutObject* curr = 0;
    ListHashSet<LayoutObject*, 16> potentialLineBreakObjects;
    potentialLineBreakObjects.add(child);
    for (curr = child->previousSibling(); curr; curr = curr->previousSibling()) {
        potentialLineBreakObjects.add(curr);

        if (curr->isFloatingOrOutOfFlowPositioned())
            continue;

        if (curr->isReplaced()) {
            InlineBox* wrapper = toLayoutBox(curr)->inlineBoxWrapper();
            if (wrapper)
                box = &wrapper->root();
        } else if (curr->isText()) {
            InlineTextBox* textBox = toLayoutText(curr)->lastTextBox();
            if (textBox)
                box = &textBox->root();
        } else if (curr->isLayoutInline()) {
            InlineBox* lastSiblingBox = toLayoutInline(curr)->lastLineBoxIncludingCulling();
            if (lastSiblingBox)
                box = &lastSiblingBox->root();
        }

        if (box)
            break;
    }
    if (!box) {
        if (inlineContainer && !inlineContainer->alwaysCreateLineBoxes()) {
            // https://bugs.webkit.org/show_bug.cgi?id=60778
            // We may have just removed a <br> with no line box that was our first child. In this case
            // we won't find a previous sibling, but firstBox can be pointing to a following sibling.
            // This isn't good enough, since we won't locate the root line box that encloses the removed
            // <br>. We have to just over-invalidate a bit and go up to our parent.
            if (!inlineContainer->ancestorLineBoxDirty()) {
                inlineContainer->parent()->dirtyLinesFromChangedChild(inlineContainer);
                inlineContainer->setAncestorLineBoxDirty(); // Mark the container to avoid dirtying the same lines again across multiple destroy() calls of the same subtree.
            }
            return;
        }
        box = &firstBox->root();
    }

    // If we found a line box, then dirty it.
    if (box) {
        RootInlineBox* adjacentBox;
        box->markDirty();

        // dirty the adjacent lines that might be affected
        // NOTE: we dirty the previous line because RootInlineBox objects cache
        // the address of the first object on the next line after a BR, which we may be
        // invalidating here.  For more info, see how LayoutBlock::layoutInlineChildren
        // calls setLineBreakInfo with the result of findNextLineBreak.  findNextLineBreak,
        // despite the name, actually returns the first LayoutObject after the BR.
        // <rdar://problem/3849947> "Typing after pasting line does not appear until after window resize."
        adjacentBox = box->prevRootBox();
        if (adjacentBox)
            adjacentBox->markDirty();
        adjacentBox = box->nextRootBox();
        // If |child| or any of its immediately previous siblings with culled lineboxes is the object after a line-break in |box| or the linebox after it
        // then that means |child| actually sits on the linebox after |box| (or is its line-break object) and so we need to dirty it as well.
        if (adjacentBox && (potentialLineBreakObjects.contains(box->lineBreakObj()) || potentialLineBreakObjects.contains(adjacentBox->lineBreakObj()) || child->isBR() || isIsolated(container->style()->unicodeBidi())))
            adjacentBox->markDirty();
    }
}

bool InspectorHighlight::buildNodeQuads(Node* node, FloatQuad* content, FloatQuad* padding, FloatQuad* border, FloatQuad* margin)
{
    LayoutObject* layoutObject = node->layoutObject();
    if (!layoutObject)
        return false;

    FrameView* containingView = layoutObject->frameView();
    if (!containingView)
        return false;
    if (!layoutObject->isBox() && !layoutObject->isLayoutInline())
        return false;

    LayoutRect contentBox;
    LayoutRect paddingBox;
    LayoutRect borderBox;
    LayoutRect marginBox;

    if (layoutObject->isBox()) {
        LayoutBox* layoutBox = toLayoutBox(layoutObject);

        // LayoutBox returns the "pure" content area box, exclusive of the scrollbars (if present), which also count towards the content area in CSS.
        const int verticalScrollbarWidth = layoutBox->verticalScrollbarWidth();
        const int horizontalScrollbarHeight = layoutBox->horizontalScrollbarHeight();
        contentBox = layoutBox->contentBoxRect();
        contentBox.setWidth(contentBox.width() + verticalScrollbarWidth);
        contentBox.setHeight(contentBox.height() + horizontalScrollbarHeight);

        paddingBox = layoutBox->paddingBoxRect();
        paddingBox.setWidth(paddingBox.width() + verticalScrollbarWidth);
        paddingBox.setHeight(paddingBox.height() + horizontalScrollbarHeight);

        borderBox = layoutBox->borderBoxRect();

        marginBox = LayoutRect(borderBox.x() - layoutBox->marginLeft(), borderBox.y() - layoutBox->marginTop(),
            borderBox.width() + layoutBox->marginWidth(), borderBox.height() + layoutBox->marginHeight());
    } else {
        LayoutInline* layoutInline = toLayoutInline(layoutObject);

        // LayoutInline's bounding box includes paddings and borders, excludes margins.
        borderBox = LayoutRect(layoutInline->linesBoundingBox());
        paddingBox = LayoutRect(borderBox.x() + layoutInline->borderLeft(), borderBox.y() + layoutInline->borderTop(),
            borderBox.width() - layoutInline->borderLeft() - layoutInline->borderRight(), borderBox.height() - layoutInline->borderTop() - layoutInline->borderBottom());
        contentBox = LayoutRect(paddingBox.x() + layoutInline->paddingLeft(), paddingBox.y() + layoutInline->paddingTop(),
            paddingBox.width() - layoutInline->paddingLeft() - layoutInline->paddingRight(), paddingBox.height() - layoutInline->paddingTop() - layoutInline->paddingBottom());
        // Ignore marginTop and marginBottom for inlines.
        marginBox = LayoutRect(borderBox.x() - layoutInline->marginLeft(), borderBox.y(),
            borderBox.width() + layoutInline->marginWidth(), borderBox.height());
    }

    *content = layoutObject->localToAbsoluteQuad(FloatRect(contentBox));
    *padding = layoutObject->localToAbsoluteQuad(FloatRect(paddingBox));
    *border = layoutObject->localToAbsoluteQuad(FloatRect(borderBox));
    *margin = layoutObject->localToAbsoluteQuad(FloatRect(marginBox));

    contentsQuadToViewport(containingView, *content);
    contentsQuadToViewport(containingView, *padding);
    contentsQuadToViewport(containingView, *border);
    contentsQuadToViewport(containingView, *margin);

    return true;
}