C++ InlineTextBox::root方法代码示例

static IntRect ellipsisRectForBox(const InlineTextBox& box, unsigned start, unsigned end)
{
    unsigned truncation = box.truncation();
    if (truncation == cNoTruncation)
        return IntRect();

    auto ellipsis = box.root().ellipsisBox();
    if (!ellipsis)
        return IntRect();
    
    IntRect rect;
    unsigned ellipsisStartPosition = start > box.start() ? start - box.start() : 0;
    ASSERT(end >= box.start());
    unsigned ellipsisEndPosition = std::min(end - box.start(), box.len());
    
    // The ellipsis should be considered to be selected if the end of
    // the selection is past the beginning of the truncation and the
    // beginning of the selection is before or at the beginning of the truncation.
    if (ellipsisEndPosition < truncation && ellipsisStartPosition > truncation)
        return IntRect();
    return ellipsis->selectionRect();
}

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();
    }
}

void RenderFlow::dirtyLinesFromChangedChild(RenderObject* child, bool adding)
{
    if (!parent() || selfNeedsLayout() || isTable())
        return;

    // For an empty inline, go ahead and propagate the check up to our parent.
    if (isInline() && !firstLineBox())
        return parent()->dirtyLinesFromChangedChild(this);
    
    // 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 = curr->inlineBoxWrapper();
            if (wrapper)
                box = wrapper->root();
        }
        else if (curr->isText()) {
            InlineTextBox* textBox = static_cast<RenderText*>(curr)->lastTextBox();
            if (textBox)
                box = textBox->root();
        }
        else if (curr->isInlineFlow()) {
            InlineRunBox* runBox = static_cast<RenderFlow*>(curr)->lastLineBox();
            if (runBox)
                box = runBox->root();
        }
        
        if (box)
            break;
    }
    if (!box && firstLineBox())
        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(RenderObject* container, RenderObject* child)
{
    if (!container->parent() || (container->isRenderBlock() && (container->selfNeedsLayout() || !container->isBlockFlow())))
        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 = 0;
    RenderObject* curr = 0;
    for (curr = child->previousSibling(); curr; curr = curr->previousSibling()) {
        if (curr->isFloatingOrOutOfFlowPositioned())
            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()) {
            InlineBox* lastSiblingBox = toRenderInline(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 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() || (curr && curr->isBR()) || insertedAfterLeadingSpace))
            adjacentBox->markDirty();
    }
}