C++ RootInlineBox类代码示例

void RenderRubyRun::layout()
{
    RenderBlockFlow::layout();
    
    RenderRubyText* rt = rubyText();
    if (!rt)
        return;

    rt->setLogicalLeft(0);
    
    // Place the RenderRubyText such that its bottom is flush with the lineTop of the first line of the RenderRubyBase.
    LayoutUnit lastLineRubyTextBottom = rt->logicalHeight();
    LayoutUnit firstLineRubyTextTop = 0;
    RootInlineBox* rootBox = rt->lastRootBox();
    if (rootBox) {
        // In order to align, we have to ignore negative leading.
        firstLineRubyTextTop = rt->firstRootBox()->logicalTopLayoutOverflow();
        lastLineRubyTextBottom = rootBox->logicalBottomLayoutOverflow();
    }
    
    if (isHorizontalWritingMode() && rt->style().rubyPosition() == RubyPositionInterCharacter) {
        // Bopomofo. We need to move the RenderRubyText over to the right side and center it
        // vertically relative to the base.
        const Font& font = style().font();
        float distanceBetweenBase = max(font.letterSpacing(), 2.0f * rt->style().font().fontMetrics().height());
        setWidth(width() + distanceBetweenBase - font.letterSpacing());
        if (RenderRubyBase* rb = rubyBase()) {
            LayoutUnit firstLineTop = 0;
            LayoutUnit lastLineBottom = logicalHeight();
            RootInlineBox* rootBox = rb->firstRootBox();
            if (rootBox)
                firstLineTop = rootBox->logicalTopLayoutOverflow();
            firstLineTop += rb->logicalTop();
            if (rootBox)
                lastLineBottom = rootBox->logicalBottomLayoutOverflow();
            lastLineBottom += rb->logicalTop();
            rt->setX(rb->x() + rb->width() - font.letterSpacing());
            LayoutUnit extent = lastLineBottom - firstLineTop;
            rt->setY(firstLineTop + (extent - rt->height()) / 2);
        }
    } else if (style().isFlippedLinesWritingMode() == (style().rubyPosition() == RubyPositionAfter)) {
        LayoutUnit firstLineTop = 0;
        if (RenderRubyBase* rb = rubyBase()) {
            RootInlineBox* rootBox = rb->firstRootBox();
            if (rootBox)
                firstLineTop = rootBox->logicalTopLayoutOverflow();
            firstLineTop += rb->logicalTop();
        }
        
        rt->setLogicalTop(-lastLineRubyTextBottom + firstLineTop);
    } else {
        LayoutUnit lastLineBottom = logicalHeight();
        if (RenderRubyBase* rb = rubyBase()) {
            RootInlineBox* rootBox = rb->lastRootBox();
            if (rootBox)
                lastLineBottom = rootBox->logicalBottomLayoutOverflow();
            lastLineBottom += rb->logicalTop();
        }

        rt->setLogicalTop(-firstLineRubyTextTop + lastLineBottom);
    }

    // Update our overflow to account for the new RenderRubyText position.
    computeOverflow(clientLogicalBottom());
}

void RenderLineBoxList::dirtyLinesFromChangedChild(RenderObject* container, RenderObject* child)
{
    if (!container->parent() || (container->isRenderBlock() && (container->selfNeedsLayout() || !container->isBlockFlow())))
        return;

    // If we have no first line box, then just bail early.
    if (!firstLineBox()) {
        // For an empty inline, go ahead and propagate the check up to our parent, unless the parent
        // is already dirty.
        if (container->isInline() && !container->parent()->selfNeedsLayout())
            container->parent()->dirtyLinesFromChangedChild(container);
        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;
    RenderObject* curr = 0;
    for (curr = child->previousSibling(); curr; curr = curr->previousSibling()) {
        if (curr->isFloatingOrPositioned())
            continue;

        if (curr->isReplaced()) {
            InlineBox* wrapper = toRenderBox(curr)->inlineBoxWrapper();
            if (wrapper)
                box = wrapper->root();
        } else if (curr->isText()) {
            InlineTextBox* textBox = toRenderText(curr)->lastTextBox();
            if (textBox)
                box = textBox->root();
        } else if (curr->isRenderInline()) {
            InlineFlowBox* flowBox = toRenderInline(curr)->lastLineBox();
            if (flowBox)
                box = flowBox->root();
        }

        if (box)
            break;
    }
    if (!box)
        box = firstLineBox()->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 RenderBlock::layoutInlineChildren
        // calls setLineBreakInfo with the result of findNextLineBreak.  findNextLineBreak,
        // despite the name, actually returns the first RenderObject after the BR.
        // <rdar://problem/3849947> "Typing after pasting line does not appear until after window resize."
        adjacentBox = box->prevRootBox();
        if (adjacentBox)
            adjacentBox->markDirty();
        if (child->isBR() || (curr && curr->isBR())) {
            adjacentBox = box->nextRootBox();
            if (adjacentBox)
                adjacentBox->markDirty();
        }
    }
}

void RenderLineBoxList::dirtyLinesFromChangedChild(RenderBoxModelObject* container, RenderObject* child)
{
    ASSERT(container->isRenderInline() || container->isRenderBlockFlow());
    if (!container->parent() || (container->isRenderBlockFlow() && container->selfNeedsLayout()))
        return;

    RenderInline* inlineContainer = container->isRenderInline() ? toRenderInline(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 = nullptr;
    RenderObject* current;
    for (current = child->previousSibling(); current; current = current->previousSibling()) {
        if (current->isFloatingOrOutOfFlowPositioned())
            continue;

        if (current->isReplaced()) {
            if (auto wrapper = downcast<RenderBox>(*current).inlineBoxWrapper())
                box = &wrapper->root();
        } if (is<RenderLineBreak>(*current)) {
            if (auto wrapper = downcast<RenderLineBreak>(*current).inlineBoxWrapper())
                box = &wrapper->root();
        } else if (is<RenderText>(*current)) {
            if (InlineTextBox* textBox = downcast<RenderText>(*current).lastTextBox())
                box = &textBox->root();
        } else if (is<RenderInline>(*current)) {
            InlineBox* lastSiblingBox = downcast<RenderInline>(*current).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 RenderBlock::layoutInlineChildren
        // calls setLineBreakInfo with the result of findNextLineBreak.  findNextLineBreak,
        // despite the name, actually returns the first RenderObject 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| has been inserted before the first element in the linebox, but after collapsed leading
        // space, the search for |child|'s linebox will go past the leading space to the previous linebox and select that
        // one as |box|. If we hit that situation here, dirty the |box| actually containing the child too. 
        bool insertedAfterLeadingSpace = box->lineBreakObj() == child->previousSibling();
        if (adjacentBox && (adjacentBox->lineBreakObj() == child || child->isBR() || (current && current->isBR())
            || insertedAfterLeadingSpace || isIsolated(container->style().unicodeBidi())))
            adjacentBox->markDirty();
    }
}

RootInlineBox* RenderSVGText::createRootInlineBox() 
{
    RootInlineBox* box = new (renderArena()) SVGRootInlineBox(this);
    box->setHasVirtualLogicalHeight();
    return box;
}