renderobject.h

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    bool isText() const  { return m_isText; }
    bool isBox() const { return m_isBox; }
    bool isInline() const { return m_inline; }  // inline object
    bool isRunIn() const { return style()->display() == RUN_IN; } // run-in object
    bool isDragging() const { return m_isDragging; }
    bool isReplaced() const { return m_replaced; } // a "replaced" element (see CSS)
    
    bool hasLayer() const { return m_hasLayer; }
    
    bool hasBoxDecorations() const { return m_paintBackground; }
    bool mustRepaintBackgroundOrBorder() const;

    bool needsLayout() const { return m_needsLayout || m_normalChildNeedsLayout || m_posChildNeedsLayout || m_needsPositionedMovementLayout; }
    bool selfNeedsLayout() const { return m_needsLayout; }
    bool needsPositionedMovementLayout() const { return m_needsPositionedMovementLayout; }
    bool needsPositionedMovementLayoutOnly() const { return m_needsPositionedMovementLayout && !m_needsLayout && !m_normalChildNeedsLayout && !m_posChildNeedsLayout; }
    bool posChildNeedsLayout() const { return m_posChildNeedsLayout; }
    bool normalChildNeedsLayout() const { return m_normalChildNeedsLayout; }
    
    bool prefWidthsDirty() const { return m_prefWidthsDirty; }

    bool isSelectionBorder() const;

    bool hasClip() const { return isPositioned() && style()->hasClip(); }
    bool hasOverflowClip() const { return m_hasOverflowClip; }

    bool hasTransform() const { return m_hasTransform; }
    bool hasMask() const { return style() && style()->hasMask(); }

    void drawLineForBoxSide(GraphicsContext*, int x1, int y1, int x2, int y2, BoxSide,
                            Color, const Color& textcolor, EBorderStyle, int adjbw1, int adjbw2);
    void drawArcForBoxSide(GraphicsContext*, int x, int y, float thickness, IntSize radius, int angleStart,
                           int angleSpan, BoxSide, Color, const Color& textcolor, EBorderStyle, bool firstCorner);

public:
    // The pseudo element style can be cached or uncached.  Use the cached method if the pseudo element doesn't respect
    // any pseudo classes (and therefore has no concept of changing state).
    RenderStyle* getCachedPseudoStyle(PseudoId, RenderStyle* parentStyle = 0) const;
    PassRefPtr<RenderStyle> getUncachedPseudoStyle(PseudoId, RenderStyle* parentStyle = 0) const;
    
    virtual void updateDragState(bool dragOn);

    RenderView* view() const;

    // Returns true if this renderer is rooted, and optionally returns the hosting view (the root of the hierarchy).
    bool isRooted(RenderView** = 0);

    Node* node() const { return m_isAnonymous ? 0 : m_node; }
    Document* document() const { return m_node->document(); }
    void setNode(Node* node) { m_node = node; }

    bool hasOutlineAnnotation() const;
    bool hasOutline() const { return style()->hasOutline() || hasOutlineAnnotation(); }

   /**
     * returns the object containing this one. can be different from parent for
     * positioned elements
     */
    RenderObject* container() const;
    virtual RenderObject* hoverAncestor() const { return parent(); }

    // IE Extension that can be called on any RenderObject.  See the implementation for the details.
    RenderBoxModelObject* offsetParent() const;

    void markContainingBlocksForLayout(bool scheduleRelayout = true, RenderObject* newRoot = 0);
    void setNeedsLayout(bool b, bool markParents = true);
    void setChildNeedsLayout(bool b, bool markParents = true);
    void setNeedsPositionedMovementLayout();
    void setPrefWidthsDirty(bool, bool markParents = true);
    void invalidateContainerPrefWidths();
    
    void setNeedsLayoutAndPrefWidthsRecalc()
    {
        setNeedsLayout(true);
        setPrefWidthsDirty(true);
    }

    void setPositioned(bool b = true)  { m_positioned = b;  }
    void setRelPositioned(bool b = true) { m_relPositioned = b; }
    void setFloating(bool b = true) { m_floating = b; }
    void setInline(bool b = true) { m_inline = b; }
    void setHasBoxDecorations(bool b = true) { m_paintBackground = b; }
    void setIsText() { m_isText = true; }
    void setIsBox() { m_isBox = true; }
    void setReplaced(bool b = true) { m_replaced = b; }
    void setHasOverflowClip(bool b = true) { m_hasOverflowClip = b; }
    void setHasLayer(bool b = true) { m_hasLayer = b; }
    void setHasTransform(bool b = true) { m_hasTransform = b; }
    void setHasReflection(bool b = true) { m_hasReflection = b; }

    void scheduleRelayout();

    void updateFillImages(const FillLayer*, const FillLayer*);
    void updateImage(StyleImage*, StyleImage*);

    // for discussion of lineHeight see CSS2 spec
    virtual int lineHeight(bool firstLine, bool isRootLineBox = false) const;
    // for the vertical-align property of inline elements
    // the offset of baseline from the top of the object.
    virtual int baselinePosition(bool firstLine, bool isRootLineBox = false) const;

    /*
     * Paint the object and its children, clipped by (x|y|w|h).
     * (tx|ty) is the calculated position of the parent
     */
    struct PaintInfo {
        PaintInfo(GraphicsContext* newContext, const IntRect& newRect, PaintPhase newPhase, bool newForceBlackText,
                  RenderObject* newPaintingRoot, ListHashSet<RenderInline*>* newOutlineObjects)
            : context(newContext)
            , rect(newRect)
            , phase(newPhase)
            , forceBlackText(newForceBlackText)
            , paintingRoot(newPaintingRoot)
            , outlineObjects(newOutlineObjects)
        {
        }

        GraphicsContext* context;
        IntRect rect;
        PaintPhase phase;
        bool forceBlackText;
        RenderObject* paintingRoot; // used to draw just one element and its visual kids
        ListHashSet<RenderInline*>* outlineObjects; // used to list outlines that should be painted by a block with inline children
    };

    virtual void paint(PaintInfo&, int tx, int ty);

    // Recursive function that computes the size and position of this object and all its descendants.
    virtual void layout();

    /* This function performs a layout only if one is needed. */
    void layoutIfNeeded() { if (needsLayout()) layout(); }

    // Called when a positioned object moves but doesn't necessarily change size.  A simplified layout is attempted
    // that just updates the object's position. If the size does change, the object remains dirty.
    virtual void tryLayoutDoingPositionedMovementOnly() { }
    
    // used for element state updates that cannot be fixed with a
    // repaint and do not need a relayout
    virtual void updateFromElement() { }

#if ENABLE(DASHBOARD_SUPPORT)
    virtual void addDashboardRegions(Vector<DashboardRegionValue>&);
    void collectDashboardRegions(Vector<DashboardRegionValue>&);
#endif

    bool hitTest(const HitTestRequest&, HitTestResult&, const IntPoint&, int tx, int ty, HitTestFilter = HitTestAll);
    virtual bool nodeAtPoint(const HitTestRequest&, HitTestResult&, int x, int y, int tx, int ty, HitTestAction);
    virtual void updateHitTestResult(HitTestResult&, const IntPoint&);

    VisiblePosition positionForCoordinates(int x, int y);
    virtual VisiblePosition positionForPoint(const IntPoint&);

    virtual void dirtyLinesFromChangedChild(RenderObject*);

    // Called to update a style that is allowed to trigger animations.
    // FIXME: Right now this will typically be called only when updating happens from the DOM on explicit elements.
    // We don't yet handle generated content animation such as first-letter or before/after (we'll worry about this later).
    void setAnimatableStyle(PassRefPtr<RenderStyle>);

    // Set the style of the object and update the state of the object accordingly.
    virtual void setStyle(PassRefPtr<RenderStyle>);

    // Updates only the local style ptr of the object.  Does not update the state of the object,
    // and so only should be called when the style is known not to have changed (or from setStyle).
    void setStyleInternal(PassRefPtr<RenderStyle>);

    // returns the containing block level element for this element.
    RenderBlock* containingBlock() const;

    // Convert the given local point to absolute coordinates
    // FIXME: Temporary. If useTransforms is true, take transforms into account. Eventually localToAbsolute() will always be transform-aware.
    FloatPoint localToAbsolute(FloatPoint localPoint = FloatPoint(), bool fixed = false, bool useTransforms = false) const;
    FloatPoint absoluteToLocal(FloatPoint, bool fixed = false, bool useTransforms = false) const;

    // Convert a local quad to absolute coordinates, taking transforms into account.
    FloatQuad localToAbsoluteQuad(const FloatQuad& quad, bool fixed = false) const
    {
        return localToContainerQuad(quad, 0, fixed);
    }
    // Convert a local quad into the coordinate system of container, taking transforms into account.
    FloatQuad localToContainerQuad(const FloatQuad&, RenderBoxModelObject* repaintContainer, bool fixed = false) const;

    // Return the offset from the container() renderer (excluding transforms)
    virtual IntSize offsetFromContainer(RenderObject*) const;

    virtual void absoluteRectsForRange(Vector<IntRect>&, unsigned startOffset = 0, unsigned endOffset = UINT_MAX, bool useSelectionHeight = false);
    
    virtual void absoluteRects(Vector<IntRect>&, int, int, bool = true) { }
    // FIXME: useTransforms should go away eventually
    IntRect absoluteBoundingBoxRect(bool useTransforms = false);

    // Build an array of quads in absolute coords for line boxes
    virtual void absoluteQuadsForRange(Vector<FloatQuad>&, unsigned startOffset = 0, unsigned endOffset = UINT_MAX, bool useSelectionHeight = false);
    virtual void absoluteQuads(Vector<FloatQuad>&, bool /*topLevel*/ = true) { }

    // the rect that will be painted if this object is passed as the paintingRoot
    IntRect paintingRootRect(IntRect& topLevelRect);

    virtual int minPrefWidth() const { return 0; }
    virtual int maxPrefWidth() const { return 0; }

    RenderStyle* style() const { return m_style.get(); }
    RenderStyle* firstLineStyle() const { return document()->usesFirstLineRules() ? firstLineStyleSlowCase() : style(); }
    RenderStyle* style(bool firstLine) const { return firstLine ? firstLineStyle() : style(); }
    
    // Anonymous blocks that are part of of a continuation chain will return their inline continuation's outline style instead.
    // This is typically only relevant when repainting.
    virtual RenderStyle* outlineStyleForRepaint() const { return style(); }
    
    void getTextDecorationColors(int decorations, Color& underline, Color& overline,
                                 Color& linethrough, bool quirksMode = false);

    // Return the RenderBox in the container chain which is responsible for painting this object, or 0
    // if painting is root-relative. This is the container that should be passed to the 'forRepaint'
    // methods.
    RenderBoxModelObject* containerForRepaint() const;
    // Actually do the repaint of rect r for this object which has been computed in the coordinate space
    // of repaintContainer. If repaintContainer is 0, repaint via the view.
    void repaintUsingContainer(RenderBoxModelObject* repaintContainer, const IntRect& r, bool immediate = false);
    
    // Repaint the entire object.  Called when, e.g., the color of a border changes, or when a border
    // style changes.
    void repaint(bool immediate = false);

    // Repaint a specific subrectangle within a given object.  The rect |r| is in the object's coordinate space.
    void repaintRectangle(const IntRect&, bool immediate = false);

    // Repaint only if our old bounds and new bounds are different.
    bool repaintAfterLayoutIfNeeded(RenderBoxModelObject* repaintContainer, const IntRect& oldBounds, const IntRect& oldOutlineBox);

    // Repaint only if the object moved.
    virtual void repaintDuringLayoutIfMoved(const IntRect& rect);

    // Called to repaint a block's floats.
    virtual void repaintOverhangingFloats(bool paintAllDescendants = false);

    bool checkForRepaintDuringLayout() const;

    // Returns the rect that should be repainted whenever this object changes.  The rect is in the view's
    // coordinate space.  This method deals with outlines and overflow.
    IntRect absoluteClippedOverflowRect()
    {
        return clippedOverflowRectForRepaint(0);
    }
    virtual IntRect clippedOverflowRectForRepaint(RenderBoxModelObject* repaintContainer);    
    virtual IntRect rectWithOutlineForRepaint(RenderBoxModelObject* repaintContainer, int outlineWidth);

    // Given a rect in the object's coordinate space, compute a rect suitable for repainting
    // that rect in view coordinates.
    void computeAbsoluteRepaintRect(IntRect& r, bool fixed = false)
    {
        return computeRectForRepaint(0, r, fixed);
    }
    // Given a rect in the object's coordinate space, compute a rect suitable for repainting
    // that rect in the coordinate space of repaintContainer.
    virtual void computeRectForRepaint(RenderBoxModelObject* repaintContainer, IntRect&, bool fixed = false);

    virtual unsigned int length() const { return 1; }

    bool isFloatingOrPositioned() const { return (isFloating() || isPositioned()); }

    bool isTransparent() const { return style()->opacity() < 1.0f; }
    float opacity() const { return style()->opacity(); }

    bool hasReflection() const { return m_hasReflection; }

    // Applied as a "slop" to dirty rect checks during the outline painting phase's dirty-rect checks.
    int maximalOutlineSize(PaintPhase) const;

    void setHasMarkupTruncation(bool b = true) { m_hasMarkupTruncation = b; }
    bool hasMarkupTruncation() const { return m_hasMarkupTruncation; }

    enum SelectionState {
        SelectionNone, // The object is not selected.
        SelectionStart, // The object either contains the start of a selection run or is the start of a run
        SelectionInside, // The object is fully encompassed by a selection run
        SelectionEnd, // The object either contains the end of a selection run or is the end of a run
        SelectionBoth // The object contains an entire run or is the sole selected object in that run
    };

    // The current selection state for an object.  For blocks, the state refers to the state of the leaf
    // descendants (as described above in the SelectionState enum declaration).
    SelectionState selectionState() const { return static_cast<SelectionState>(m_selectionState);; }

    // Sets the selection state for an object.
    virtual void setSelectionState(SelectionState state) { m_selectionState = state; }

    // A single rectangle that encompasses all of the selected objects within this object.  Used to determine the tightest
    // possible bounding box for the selection.
    IntRect selectionRect(bool clipToVisibleContent = true) { return selectionRectForRepaint(0, clipToVisibleContent); }
    virtual IntRect selectionRectForRepaint(RenderBoxModelObject* /*repaintContainer*/, bool /*clipToVisibleContent*/ = true) { return IntRect(); }

    // Whether or not an object can be part of the leaf elements of the selection.
    virtual bool canBeSelectionLeaf() const { return false; }

    // Whether or not a block has selected children.
    bool hasSelectedChildren() const { return m_selectionState != SelectionNone; }

    // Obtains the selection colors that should be used when painting a selection.
    Color selectionBackgroundColor() const;
    Color selectionForegroundColor() const;

    // Whether or not a given block needs to paint selection gaps.
    virtual bool shouldPaintSelectionGaps() const { return false; }

    Node* draggableNode(bool dhtmlOK, bool uaOK, int x, int y, bool& dhtmlWillDrag) const;