renderobject.h

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    /**
     * Returns the local coordinates of the caret within this render object.
     * @param caretOffset zero-based offset determining position within the render object.
     * @param extraWidthToEndOfLine optional out arg to give extra width to end of line -
     * useful for character range rect computations
     */
    virtual IntRect localCaretRect(InlineBox*, int caretOffset, int* extraWidthToEndOfLine = 0);

    virtual void calcVerticalMargins() { }
    bool isTopMarginQuirk() const { return m_topMarginQuirk; }
    bool isBottomMarginQuirk() const { return m_bottomMarginQuirk; }
    void setTopMarginQuirk(bool b = true) { m_topMarginQuirk = b; }
    void setBottomMarginQuirk(bool b = true) { m_bottomMarginQuirk = b; }

    // When performing a global document tear-down, the renderer of the document is cleared.  We use this
    // as a hook to detect the case of document destruction and don't waste time doing unnecessary work.
    bool documentBeingDestroyed() const;

    virtual void destroy();

    // Virtual function helpers for CSS3 Flexible Box Layout
    virtual bool isFlexibleBox() const { return false; }
    virtual bool isFlexingChildren() const { return false; }
    virtual bool isStretchingChildren() const { return false; }

    virtual int caretMinOffset() const;
    virtual int caretMaxOffset() const;
    virtual unsigned caretMaxRenderedOffset() const;

    virtual int previousOffset(int current) const;
    virtual int previousOffsetForBackwardDeletion(int current) const;
    virtual int nextOffset(int current) const;

    virtual void imageChanged(CachedImage*, const IntRect* = 0);
    virtual void imageChanged(WrappedImagePtr, const IntRect* = 0) { }
    virtual bool willRenderImage(CachedImage*);

    virtual void selectionStartEnd(int& spos, int& epos) const;

    RenderObject* paintingRootForChildren(PaintInfo& paintInfo) const
    {
        // if we're the painting root, kids draw normally, and see root of 0
        return (!paintInfo.paintingRoot || paintInfo.paintingRoot == this) ? 0 : paintInfo.paintingRoot;
    }

    bool shouldPaintWithinRoot(PaintInfo& paintInfo) const
    {
        return !paintInfo.paintingRoot || paintInfo.paintingRoot == this;
    }

    bool hasOverrideSize() const { return m_hasOverrideSize; }
    void setHasOverrideSize(bool b) { m_hasOverrideSize = b; }
    
    void remove() { if (parent()) parent()->removeChild(this); }

    AnimationController* animation() const;

    bool visibleToHitTesting() const { return style()->visibility() == VISIBLE && style()->pointerEvents() != PE_NONE; }

    // Map points and quads through elements, potentially via 3d transforms. You should never need to call these directly; use
    // localToAbsolute/absoluteToLocal methods instead.
    virtual void mapLocalToContainer(RenderBoxModelObject* repaintContainer, bool useTransforms, bool fixed, TransformState&) const;
    virtual void mapAbsoluteToLocalPoint(bool fixed, bool useTransforms, TransformState&) const;

    TransformationMatrix transformFromContainer(const RenderObject* container, const IntSize& offsetInContainer) const;
    
    virtual void addFocusRingRects(GraphicsContext*, int /*tx*/, int /*ty*/) { };

    IntRect absoluteOutlineBounds() const
    {
        return outlineBoundsForRepaint(0);
    }

    bool replacedHasOverflow() const { return m_replacedHasOverflow; }
    void setReplacedHasOverflow(bool b = true) { m_replacedHasOverflow = b; }
    
protected:
    // Overrides should call the superclass at the end
    virtual void styleWillChange(StyleDifference, const RenderStyle* newStyle);
    // Overrides should call the superclass at the start
    virtual void styleDidChange(StyleDifference, const RenderStyle* oldStyle);

    void paintOutline(GraphicsContext*, int tx, int ty, int w, int h, const RenderStyle*);
    void addPDFURLRect(GraphicsContext*, const IntRect&);

    virtual IntRect viewRect() const;

    void adjustRectForOutlineAndShadow(IntRect&) const;

    void arenaDelete(RenderArena*, void* objectBase);

    virtual IntRect outlineBoundsForRepaint(RenderBoxModelObject* /*repaintContainer*/) const { return IntRect(); }

    class LayoutRepainter {
    public:
        LayoutRepainter(RenderObject& object, bool checkForRepaint, const IntRect* oldBounds = 0)
            : m_object(object)
            , m_repaintContainer(0)
            , m_checkForRepaint(checkForRepaint)
        {
            if (m_checkForRepaint) {
                m_repaintContainer = m_object.containerForRepaint();
                m_oldBounds = oldBounds ? *oldBounds : m_object.clippedOverflowRectForRepaint(m_repaintContainer);
                m_oldOutlineBox = m_object.outlineBoundsForRepaint(m_repaintContainer);
            }
        }
        
        // Return true if it repainted.
        bool repaintAfterLayout()
        {
            return m_checkForRepaint ? m_object.repaintAfterLayoutIfNeeded(m_repaintContainer, m_oldBounds, m_oldOutlineBox) : false;
        }
        
        bool checkForRepaint() const { return m_checkForRepaint; }
        
    private:
        RenderObject& m_object;
        RenderBoxModelObject* m_repaintContainer;
        IntRect m_oldBounds;
        IntRect m_oldOutlineBox;
        bool m_checkForRepaint;
    };
    
private:
    RenderStyle* firstLineStyleSlowCase() const;
    StyleDifference adjustStyleDifference(StyleDifference, unsigned contextSensitiveProperties) const;
    
    RefPtr<RenderStyle> m_style;

    Node* m_node;

    RenderObject* m_parent;
    RenderObject* m_previous;
    RenderObject* m_next;

#ifndef NDEBUG
    bool m_hasAXObject;
    bool m_setNeedsLayoutForbidden : 1;
#endif

    // 32 bits have been used here. THERE ARE NO FREE BITS AVAILABLE.
    bool m_needsLayout               : 1;
    bool m_needsPositionedMovementLayout :1;
    bool m_normalChildNeedsLayout    : 1;
    bool m_posChildNeedsLayout       : 1;
    bool m_prefWidthsDirty           : 1;
    bool m_floating                  : 1;

    bool m_positioned                : 1;
    bool m_relPositioned             : 1;
    bool m_paintBackground           : 1; // if the box has something to paint in the
                                          // background painting phase (background, border, etc)

    bool m_isAnonymous               : 1;
    bool m_isText                    : 1;
    bool m_isBox                     : 1;
    bool m_inline                    : 1;
    bool m_replaced                  : 1;
    bool m_isDragging                : 1;

    bool m_hasLayer                  : 1;
    bool m_hasOverflowClip           : 1;
    bool m_hasTransform              : 1;
    bool m_hasReflection             : 1;

    bool m_hasOverrideSize           : 1;
    
public:
    bool m_hasCounterNodeMap         : 1;
    bool m_everHadLayout             : 1;

private:
    // These bitfields are moved here from subclasses to pack them together
    // from RenderBlock
    bool m_childrenInline : 1;
    bool m_topMarginQuirk : 1;
    bool m_bottomMarginQuirk : 1;
    bool m_hasMarkupTruncation : 1;
    unsigned m_selectionState : 3; // SelectionState
    bool m_hasColumns : 1;
    
    // from RenderTableCell
    bool m_cellWidthChanged : 1;

    // from RenderReplaced
    bool m_replacedHasOverflow : 1;

private:
    // Store state between styleWillChange and styleDidChange
    static bool s_affectsParentBlock;
};

inline bool RenderObject::documentBeingDestroyed() const
{
    return !document()->renderer();
}

inline void RenderObject::setNeedsLayout(bool b, bool markParents)
{
    bool alreadyNeededLayout = m_needsLayout;
    m_needsLayout = b;
    if (b) {
        ASSERT(!isSetNeedsLayoutForbidden());
        if (!alreadyNeededLayout) {
            if (markParents)
                markContainingBlocksForLayout();
            if (hasLayer())
                setLayerNeedsFullRepaint();
        }
    } else {
        m_everHadLayout = true;
        m_posChildNeedsLayout = false;
        m_normalChildNeedsLayout = false;
        m_needsPositionedMovementLayout = false;
    }
}

inline void RenderObject::setChildNeedsLayout(bool b, bool markParents)
{
    bool alreadyNeededLayout = m_normalChildNeedsLayout;
    m_normalChildNeedsLayout = b;
    if (b) {
        ASSERT(!isSetNeedsLayoutForbidden());
        if (!alreadyNeededLayout && markParents)
            markContainingBlocksForLayout();
    } else {
        m_posChildNeedsLayout = false;
        m_normalChildNeedsLayout = false;
        m_needsPositionedMovementLayout = false;
    }
}

inline void RenderObject::setNeedsPositionedMovementLayout()
{
    bool alreadyNeededLayout = needsLayout();
    m_needsPositionedMovementLayout = true;
    if (!alreadyNeededLayout) {
        markContainingBlocksForLayout();
        if (hasLayer())
            setLayerNeedsFullRepaint();
    }
}

inline bool objectIsRelayoutBoundary(const RenderObject *obj) 
{
    // FIXME: In future it may be possible to broaden this condition in order to improve performance.
    // Table cells are excluded because even when their CSS height is fixed, their height()
    // may depend on their contents.
    return obj->isTextControl()
        || obj->hasOverflowClip() && !obj->style()->width().isIntrinsicOrAuto() && !obj->style()->height().isIntrinsicOrAuto() && !obj->style()->height().isPercent() && !obj->isTableCell()
#if ENABLE(SVG)
           || obj->isSVGRoot()
#endif
           ;
}

inline void RenderObject::markContainingBlocksForLayout(bool scheduleRelayout, RenderObject* newRoot)
{
    ASSERT(!scheduleRelayout || !newRoot);

    RenderObject* o = container();
    RenderObject* last = this;

    while (o) {
        if (!last->isText() && (last->style()->position() == FixedPosition || last->style()->position() == AbsolutePosition)) {
            if ((last->style()->top().isAuto() && last->style()->bottom().isAuto()) || last->style()->top().isStatic()) {
                RenderObject* parent = last->parent();
                if (!parent->normalChildNeedsLayout()) {
                    parent->setChildNeedsLayout(true, false);
                    if (parent != newRoot)
                        parent->markContainingBlocksForLayout(scheduleRelayout, newRoot);
                }
            }
            if (o->m_posChildNeedsLayout)
                return;
            o->m_posChildNeedsLayout = true;
            ASSERT(!o->isSetNeedsLayoutForbidden());
        } else {
            if (o->m_normalChildNeedsLayout)
                return;
            o->m_normalChildNeedsLayout = true;
            ASSERT(!o->isSetNeedsLayoutForbidden());
        }

        if (o == newRoot)
            return;

        last = o;
        if (scheduleRelayout && objectIsRelayoutBoundary(last))
            break;
        o = o->container();
    }

    if (scheduleRelayout)
        last->scheduleRelayout();
}

} // namespace WebCore

#ifndef NDEBUG
// Outside the WebCore namespace for ease of invocation from gdb.
void showTree(const WebCore::RenderObject*);
#endif

#endif // RenderObject_h