1/*
2 * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
3 *           (C) 2000 Antti Koivisto (koivisto@kde.org)
4 *           (C) 2000 Dirk Mueller (mueller@kde.org)
5 *           (C) 2004 Allan Sandfeld Jensen (kde@carewolf.com)
6 * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2012 Apple Inc. All rights reserved.
7 * Copyright (C) 2009 Google Inc. All rights reserved.
8 *
9 * This library is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Library General Public
11 * License as published by the Free Software Foundation; either
12 * version 2 of the License, or (at your option) any later version.
13 *
14 * This library is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17 * Library General Public License for more details.
18 *
19 * You should have received a copy of the GNU Library General Public License
20 * along with this library; see the file COPYING.LIB.  If not, write to
21 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
22 * Boston, MA 02110-1301, USA.
23 *
24 */
25
26#ifndef RenderObject_h
27#define RenderObject_h
28
29#include "CachedImageClient.h"
30#include "DocumentStyleSheetCollection.h"
31#include "Element.h"
32#include "FloatQuad.h"
33#include "Frame.h"
34#include "LayoutRect.h"
35#include "PaintPhase.h"
36#include "RenderStyle.h"
37#include "ScrollBehavior.h"
38#include "StyleInheritedData.h"
39#include "TextAffinity.h"
40#include <wtf/HashSet.h>
41
42namespace WebCore {
43
44class AffineTransform;
45class AnimationController;
46class Cursor;
47class Document;
48class HitTestLocation;
49class HitTestResult;
50class InlineBox;
51class Path;
52class Position;
53class PseudoStyleRequest;
54class RenderBoxModelObject;
55class RenderInline;
56class RenderBlock;
57class RenderElement;
58class RenderFlowThread;
59class RenderGeometryMap;
60class RenderLayer;
61class RenderLayerModelObject;
62class RenderNamedFlowThread;
63class RenderRegion;
64class RenderTheme;
65class SelectionSubtreeRoot;
66class TransformState;
67class VisiblePosition;
68#if PLATFORM(IOS)
69class SelectionRect;
70#endif
71
72struct PaintInfo;
73
74enum CursorDirective {
75    SetCursorBasedOnStyle,
76    SetCursor,
77    DoNotSetCursor
78};
79
80enum HitTestFilter {
81    HitTestAll,
82    HitTestSelf,
83    HitTestDescendants
84};
85
86enum HitTestAction {
87    HitTestBlockBackground,
88    HitTestChildBlockBackground,
89    HitTestChildBlockBackgrounds,
90    HitTestFloat,
91    HitTestForeground
92};
93
94// Sides used when drawing borders and outlines. The values should run clockwise from top.
95enum BoxSide {
96    BSTop,
97    BSRight,
98    BSBottom,
99    BSLeft
100};
101
102enum MarkingBehavior {
103    MarkOnlyThis,
104    MarkContainingBlockChain,
105};
106
107enum MapCoordinatesMode {
108    IsFixed = 1 << 0,
109    UseTransforms = 1 << 1,
110    ApplyContainerFlip = 1 << 2
111};
112typedef unsigned MapCoordinatesFlags;
113
114#if PLATFORM(IOS)
115const int caretWidth = 2; // This value should be kept in sync with UIKit. See <rdar://problem/15580601>.
116#else
117const int caretWidth = 1;
118#endif
119
120#if ENABLE(DASHBOARD_SUPPORT)
121struct AnnotatedRegionValue {
122    bool operator==(const AnnotatedRegionValue& o) const
123    {
124        return type == o.type && bounds == o.bounds && clip == o.clip && label == o.label;
125    }
126    bool operator!=(const AnnotatedRegionValue& o) const
127    {
128        return !(*this == o);
129    }
130
131    LayoutRect bounds;
132    String label;
133    LayoutRect clip;
134    int type;
135};
136#endif
137
138#ifndef NDEBUG
139const int showTreeCharacterOffset = 39;
140#endif
141
142// Base class for all rendering tree objects.
143class RenderObject : public CachedImageClient {
144    WTF_MAKE_FAST_ALLOCATED;
145    friend class RenderBlock;
146    friend class RenderBlockFlow;
147    friend class RenderElement;
148    friend class RenderLayer;
149public:
150    // Anonymous objects should pass the document as their node, and they will then automatically be
151    // marked as anonymous in the constructor.
152    explicit RenderObject(Node&);
153    virtual ~RenderObject();
154
155    RenderTheme& theme() const;
156
157    virtual const char* renderName() const = 0;
158
159    RenderElement* parent() const { return m_parent; }
160    bool isDescendantOf(const RenderObject*) const;
161
162    RenderObject* previousSibling() const { return m_previous; }
163    RenderObject* nextSibling() const { return m_next; }
164
165    // Use RenderElement versions instead.
166    virtual RenderObject* firstChildSlow() const { return nullptr; }
167    virtual RenderObject* lastChildSlow() const { return nullptr; }
168
169    RenderObject* nextInPreOrder() const;
170    RenderObject* nextInPreOrder(const RenderObject* stayWithin) const;
171    RenderObject* nextInPreOrderAfterChildren() const;
172    RenderObject* nextInPreOrderAfterChildren(const RenderObject* stayWithin) const;
173    RenderObject* previousInPreOrder() const;
174    RenderObject* previousInPreOrder(const RenderObject* stayWithin) const;
175    RenderObject* childAt(unsigned) const;
176
177    RenderObject* firstLeafChild() const;
178    RenderObject* lastLeafChild() const;
179
180#if ENABLE(IOS_TEXT_AUTOSIZING)
181    // Minimal distance between the block with fixed height and overflowing content and the text block to apply text autosizing.
182    // The greater this constant is the more potential places we have where autosizing is turned off.
183    // So it should be as low as possible. There are sites that break at 2.
184    static const int TextAutoSizingFixedHeightDepth = 3;
185
186    enum BlockContentHeightType {
187        FixedHeight,
188        FlexibleHeight,
189        OverflowHeight
190    };
191
192    RenderObject* traverseNext(const RenderObject* stayWithin) const;
193    typedef bool (*TraverseNextInclusionFunction)(const RenderObject*);
194    typedef BlockContentHeightType (*HeightTypeTraverseNextInclusionFunction)(const RenderObject*);
195
196    RenderObject* traverseNext(const RenderObject* stayWithin, TraverseNextInclusionFunction) const;
197    RenderObject* traverseNext(const RenderObject* stayWithin, HeightTypeTraverseNextInclusionFunction, int& currentDepth,  int& newFixedDepth) const;
198
199    void adjustComputedFontSizesOnBlocks(float size, float visibleWidth);
200    void resetTextAutosizing();
201#endif
202
203    RenderLayer* enclosingLayer() const;
204
205    // Scrolling is a RenderBox concept, however some code just cares about recursively scrolling our enclosing ScrollableArea(s).
206    bool scrollRectToVisible(const LayoutRect&, const ScrollAlignment& alignX = ScrollAlignment::alignCenterIfNeeded, const ScrollAlignment& alignY = ScrollAlignment::alignCenterIfNeeded);
207
208    // Convenience function for getting to the nearest enclosing box of a RenderObject.
209    RenderBox& enclosingBox() const;
210    RenderBoxModelObject& enclosingBoxModelObject() const;
211
212    bool fixedPositionedWithNamedFlowContainingBlock() const;
213
214    enum ShouldUseFlowThreadCache {
215        UseFlowThreadCache,
216        SkipFlowThreadCache
217    };
218
219    // Function to return our enclosing flow thread if we are contained inside one. This
220    // function follows the containing block chain.
221    RenderFlowThread* flowThreadContainingBlock(ShouldUseFlowThreadCache useCache = UseFlowThreadCache) const
222    {
223        if (flowThreadState() == NotInsideFlowThread)
224            return 0;
225        return (useCache == SkipFlowThreadCache) ? locateFlowThreadContainingBlockNoCache() : locateFlowThreadContainingBlock();
226    }
227
228    RenderNamedFlowFragment* currentRenderNamedFlowFragment() const;
229
230    // FIXME: The meaning of this function is unclear.
231    virtual bool isEmpty() const { return !firstChildSlow(); }
232
233#ifndef NDEBUG
234    void setHasAXObject(bool flag) { m_hasAXObject = flag; }
235    bool hasAXObject() const { return m_hasAXObject; }
236
237    // Helper class forbidding calls to setNeedsLayout() during its lifetime.
238    class SetLayoutNeededForbiddenScope {
239    public:
240        explicit SetLayoutNeededForbiddenScope(RenderObject*, bool isForbidden = true);
241        ~SetLayoutNeededForbiddenScope();
242    private:
243        RenderObject* m_renderObject;
244        bool m_preexistingForbidden;
245    };
246#endif
247
248    // Obtains the nearest enclosing block (including this block) that contributes a first-line style to our inline
249    // children.
250    virtual RenderBlock* firstLineBlock() const;
251
252    // Called when an object that was floating or positioned becomes a normal flow object
253    // again.  We have to make sure the render tree updates as needed to accommodate the new
254    // normal flow object.
255    void handleDynamicFloatPositionChange();
256    void removeAnonymousWrappersForInlinesIfNecessary();
257
258    // RenderObject tree manipulation
259    //////////////////////////////////////////
260    virtual bool canHaveChildren() const = 0;
261    virtual bool canHaveGeneratedChildren() const;
262    virtual bool createsAnonymousWrapper() const { return false; }
263    //////////////////////////////////////////
264
265protected:
266    //////////////////////////////////////////
267    // Helper functions. Dangerous to use!
268    void setPreviousSibling(RenderObject* previous) { m_previous = previous; }
269    void setNextSibling(RenderObject* next) { m_next = next; }
270    void setParent(RenderElement*);
271    //////////////////////////////////////////
272private:
273#ifndef NDEBUG
274    bool isSetNeedsLayoutForbidden() const { return m_setNeedsLayoutForbidden; }
275    void setNeedsLayoutIsForbidden(bool flag) { m_setNeedsLayoutForbidden = flag; }
276#endif
277
278    void addAbsoluteRectForLayer(LayoutRect& result);
279    void setLayerNeedsFullRepaint();
280    void setLayerNeedsFullRepaintForPositionedMovementLayout();
281
282public:
283#ifndef NDEBUG
284    void showTreeForThis() const;
285    void showRenderTreeForThis() const;
286    void showLineTreeForThis() const;
287
288    void showRenderObject() const;
289    // We don't make printedCharacters an optional parameter so that
290    // showRenderObject can be called from gdb easily.
291    void showRenderObject(int) const;
292    void showRenderTreeAndMark(const RenderObject* = 0, const char* = 0, const RenderObject* = 0, const char* = 0, int = 0) const;
293    void showRegionsInformation(int&) const;
294#endif
295
296public:
297    bool isPseudoElement() const { return node() && node()->isPseudoElement(); }
298
299    bool isRenderElement() const { return !isText(); }
300    bool isRenderReplaced() const;
301    bool isBoxModelObject() const;
302    bool isRenderBlock() const;
303    bool isRenderBlockFlow() const;
304    bool isRenderInline() const;
305    bool isRenderLayerModelObject() const;
306
307    virtual bool isCounter() const { return false; }
308    virtual bool isQuote() const { return false; }
309
310#if ENABLE(DETAILS_ELEMENT)
311    virtual bool isDetailsMarker() const { return false; }
312#endif
313    virtual bool isEmbeddedObject() const { return false; }
314    virtual bool isFieldset() const { return false; }
315    virtual bool isFileUploadControl() const { return false; }
316    virtual bool isFrame() const { return false; }
317    virtual bool isFrameSet() const { return false; }
318    virtual bool isImage() const { return false; }
319    virtual bool isInlineBlockOrInlineTable() const { return false; }
320    virtual bool isListBox() const { return false; }
321    virtual bool isListItem() const { return false; }
322    virtual bool isListMarker() const { return false; }
323    virtual bool isMedia() const { return false; }
324    virtual bool isMenuList() const { return false; }
325#if ENABLE(METER_ELEMENT)
326    virtual bool isMeter() const { return false; }
327#endif
328    virtual bool isSnapshottedPlugIn() const { return false; }
329    virtual bool isProgress() const { return false; }
330    virtual bool isRenderSVGBlock() const { return false; };
331    virtual bool isRenderButton() const { return false; }
332    virtual bool isRenderIFrame() const { return false; }
333    virtual bool isRenderImage() const { return false; }
334    virtual bool isRenderRegion() const { return false; }
335    virtual bool isRenderNamedFlowFragment() const { return false; }
336    virtual bool isReplica() const { return false; }
337
338    virtual bool isRuby() const { return false; }
339    virtual bool isRubyBase() const { return false; }
340    virtual bool isRubyRun() const { return false; }
341    virtual bool isRubyText() const { return false; }
342
343    virtual bool isSlider() const { return false; }
344    virtual bool isSliderThumb() const { return false; }
345    virtual bool isTable() const { return false; }
346    virtual bool isTableCell() const { return false; }
347    virtual bool isRenderTableCol() const { return false; }
348    virtual bool isTableCaption() const { return false; }
349    virtual bool isTableRow() const { return false; }
350    virtual bool isTableSection() const { return false; }
351    virtual bool isTextControl() const { return false; }
352    virtual bool isTextArea() const { return false; }
353    virtual bool isTextField() const { return false; }
354    virtual bool isTextControlInnerBlock() const { return false; }
355    virtual bool isVideo() const { return false; }
356    virtual bool isWidget() const { return false; }
357    virtual bool isCanvas() const { return false; }
358#if ENABLE(FULLSCREEN_API)
359    virtual bool isRenderFullScreen() const { return false; }
360    virtual bool isRenderFullScreenPlaceholder() const { return false; }
361#endif
362#if ENABLE(CSS_GRID_LAYOUT)
363    virtual bool isRenderGrid() const { return false; }
364#endif
365    virtual bool isRenderFlowThread() const { return false; }
366    virtual bool isRenderNamedFlowThread() const { return false; }
367    bool isInFlowRenderFlowThread() const { return isRenderFlowThread() && !isOutOfFlowPositioned(); }
368    bool isOutOfFlowRenderFlowThread() const { return isRenderFlowThread() && isOutOfFlowPositioned(); }
369
370    virtual bool isMultiColumnBlockFlow() const { return false; }
371    virtual bool isRenderMultiColumnSet() const { return false; }
372    virtual bool isRenderMultiColumnFlowThread() const { return false; }
373    virtual bool isRenderMultiColumnSpannerPlaceholder() const { return false; }
374
375    virtual bool isRenderScrollbarPart() const { return false; }
376
377    bool isRoot() const { return document().documentElement() == &m_node; }
378    bool isBody() const { return node() && node()->hasTagName(HTMLNames::bodyTag); }
379    bool isHR() const { return node() && node()->hasTagName(HTMLNames::hrTag); }
380    bool isLegend() const;
381
382    bool isHTMLMarquee() const;
383
384    bool isTablePart() const { return isTableCell() || isRenderTableCol() || isTableCaption() || isTableRow() || isTableSection(); }
385
386    inline bool isBeforeContent() const;
387    inline bool isAfterContent() const;
388    inline bool isBeforeOrAfterContent() const;
389    static inline bool isBeforeContent(const RenderObject* obj) { return obj && obj->isBeforeContent(); }
390    static inline bool isAfterContent(const RenderObject* obj) { return obj && obj->isAfterContent(); }
391    static inline bool isBeforeOrAfterContent(const RenderObject* obj) { return obj && obj->isBeforeOrAfterContent(); }
392
393    bool hasCounterNodeMap() const { return m_bitfields.hasCounterNodeMap(); }
394    void setHasCounterNodeMap(bool hasCounterNodeMap) { m_bitfields.setHasCounterNodeMap(hasCounterNodeMap); }
395    bool everHadLayout() const { return m_bitfields.everHadLayout(); }
396
397    bool childrenInline() const { return m_bitfields.childrenInline(); }
398    void setChildrenInline(bool b) { m_bitfields.setChildrenInline(b); }
399
400    enum FlowThreadState {
401        NotInsideFlowThread = 0,
402        InsideOutOfFlowThread = 1,
403        InsideInFlowThread = 2,
404    };
405
406    void setFlowThreadStateIncludingDescendants(FlowThreadState);
407
408    FlowThreadState flowThreadState() const { return m_bitfields.flowThreadState(); }
409    void setFlowThreadState(FlowThreadState state) { m_bitfields.setFlowThreadState(state); }
410
411    virtual bool requiresForcedStyleRecalcPropagation() const { return false; }
412
413#if ENABLE(MATHML)
414    virtual bool isRenderMathMLBlock() const { return false; }
415    virtual bool isRenderMathMLTable() const { return false; }
416    virtual bool isRenderMathMLOperator() const { return false; }
417    virtual bool isRenderMathMLRadicalOperator() const { return false; }
418    virtual bool isRenderMathMLRow() const { return false; }
419    virtual bool isRenderMathMLMath() const { return false; }
420    virtual bool isRenderMathMLFenced() const { return false; }
421    virtual bool isRenderMathMLFraction() const { return false; }
422    virtual bool isRenderMathMLRoot() const { return false; }
423    virtual bool isRenderMathMLRootWrapper() const { return false; }
424    virtual bool isRenderMathMLSpace() const { return false; }
425    virtual bool isRenderMathMLSquareRoot() const { return false; }
426    virtual bool isRenderMathMLScripts() const { return false; }
427    virtual bool isRenderMathMLScriptsWrapper() const { return false; }
428    virtual bool isRenderMathMLToken() const { return false; }
429    virtual bool isRenderMathMLUnderOver() const { return false; }
430#endif // ENABLE(MATHML)
431
432    // FIXME: Until all SVG renders can be subclasses of RenderSVGModelObject we have
433    // to add SVG renderer methods to RenderObject with an ASSERT_NOT_REACHED() default implementation.
434    virtual bool isRenderSVGModelObject() const { return false; }
435    virtual bool isSVGRoot() const { return false; }
436    virtual bool isSVGContainer() const { return false; }
437    virtual bool isSVGTransformableContainer() const { return false; }
438    virtual bool isSVGViewportContainer() const { return false; }
439    virtual bool isSVGGradientStop() const { return false; }
440    virtual bool isSVGHiddenContainer() const { return false; }
441    virtual bool isSVGPath() const { return false; }
442    virtual bool isSVGShape() const { return false; }
443    virtual bool isSVGText() const { return false; }
444    virtual bool isSVGTextPath() const { return false; }
445    virtual bool isSVGInline() const { return false; }
446    virtual bool isSVGInlineText() const { return false; }
447    virtual bool isSVGImage() const { return false; }
448    virtual bool isSVGForeignObject() const { return false; }
449    virtual bool isSVGResourceContainer() const { return false; }
450    virtual bool isSVGResourceFilter() const { return false; }
451    virtual bool isSVGResourceFilterPrimitive() const { return false; }
452
453    // FIXME: Those belong into a SVG specific base-class for all renderers (see above)
454    // Unfortunately we don't have such a class yet, because it's not possible for all renderers
455    // to inherit from RenderSVGObject -> RenderObject (some need RenderBlock inheritance for instance)
456    virtual void setNeedsTransformUpdate() { }
457    virtual void setNeedsBoundariesUpdate();
458    virtual bool needsBoundariesUpdate() { return false; }
459
460    // Per SVG 1.1 objectBoundingBox ignores clipping, masking, filter effects, opacity and stroke-width.
461    // This is used for all computation of objectBoundingBox relative units and by SVGLocatable::getBBox().
462    // NOTE: Markers are not specifically ignored here by SVG 1.1 spec, but we ignore them
463    // since stroke-width is ignored (and marker size can depend on stroke-width).
464    // objectBoundingBox is returned local coordinates.
465    // The name objectBoundingBox is taken from the SVG 1.1 spec.
466    virtual FloatRect objectBoundingBox() const;
467    virtual FloatRect strokeBoundingBox() const;
468
469    // Returns the smallest rectangle enclosing all of the painted content
470    // respecting clipping, masking, filters, opacity, stroke-width and markers
471    virtual FloatRect repaintRectInLocalCoordinates() const;
472
473    // This only returns the transform="" value from the element
474    // most callsites want localToParentTransform() instead.
475    virtual AffineTransform localTransform() const;
476
477    // Returns the full transform mapping from local coordinates to local coords for the parent SVG renderer
478    // This includes any viewport transforms and x/y offsets as well as the transform="" value off the element.
479    virtual const AffineTransform& localToParentTransform() const;
480
481    // SVG uses FloatPoint precise hit testing, and passes the point in parent
482    // coordinates instead of in repaint container coordinates.  Eventually the
483    // rest of the rendering tree will move to a similar model.
484    virtual bool nodeAtFloatPoint(const HitTestRequest&, HitTestResult&, const FloatPoint& pointInParent, HitTestAction);
485
486    bool hasAspectRatio() const { return isReplaced() && (isImage() || isVideo() || isCanvas()); }
487    bool isAnonymous() const { return m_bitfields.isAnonymous(); }
488    bool isAnonymousBlock() const
489    {
490        // This function is kept in sync with anonymous block creation conditions in
491        // RenderBlock::createAnonymousBlock(). This includes creating an anonymous
492        // RenderBlock having a BLOCK or BOX display. Other classes such as RenderTextFragment
493        // are not RenderBlocks and will return false. See https://bugs.webkit.org/show_bug.cgi?id=56709.
494        return isAnonymous() && (style().display() == BLOCK || style().display() == BOX) && style().styleType() == NOPSEUDO && isRenderBlock() && !isListMarker() && !isRenderFlowThread() && !isRenderMultiColumnSet() && !isRenderView()
495#if ENABLE(FULLSCREEN_API)
496            && !isRenderFullScreen()
497            && !isRenderFullScreenPlaceholder()
498#endif
499#if ENABLE(MATHML)
500            && !isRenderMathMLBlock()
501#endif
502            ;
503    }
504    bool isElementContinuation() const { return node() && node()->renderer() != this; }
505    bool isInlineElementContinuation() const { return isElementContinuation() && isInline(); }
506    bool isBlockElementContinuation() const { return isElementContinuation() && !isInline(); }
507    virtual RenderBoxModelObject* virtualContinuation() const { return 0; }
508
509    bool isFloating() const { return m_bitfields.floating(); }
510
511    bool isOutOfFlowPositioned() const { return m_bitfields.isOutOfFlowPositioned(); } // absolute or fixed positioning
512    bool isInFlowPositioned() const { return m_bitfields.isRelPositioned() || m_bitfields.isStickyPositioned(); } // relative or sticky positioning
513    bool isRelPositioned() const { return m_bitfields.isRelPositioned(); } // relative positioning
514    bool isStickyPositioned() const { return m_bitfields.isStickyPositioned(); }
515    bool isPositioned() const { return m_bitfields.isPositioned(); }
516
517    bool isText() const  { return !m_bitfields.isBox() && m_bitfields.isTextOrRenderView(); }
518    bool isLineBreak() const { return m_bitfields.isLineBreak(); }
519    bool isBR() const { return isLineBreak() && !isWBR(); }
520    bool isLineBreakOpportunity() const { return isLineBreak() && isWBR(); }
521    bool isTextOrLineBreak() const { return isText() || isLineBreak(); }
522    bool isBox() const { return m_bitfields.isBox(); }
523    bool isRenderView() const  { return m_bitfields.isBox() && m_bitfields.isTextOrRenderView(); }
524    bool isInline() const { return m_bitfields.isInline(); } // inline object
525    bool isDragging() const { return m_bitfields.isDragging(); }
526    bool isReplaced() const { return m_bitfields.isReplaced(); } // a "replaced" element (see CSS)
527    bool isHorizontalWritingMode() const { return m_bitfields.horizontalWritingMode(); }
528
529    bool hasLayer() const { return m_bitfields.hasLayer(); }
530
531    enum BoxDecorationState {
532        NoBoxDecorations,
533        HasBoxDecorationsAndBackgroundObscurationStatusInvalid,
534        HasBoxDecorationsAndBackgroundIsKnownToBeObscured,
535        HasBoxDecorationsAndBackgroundMayBeVisible,
536    };
537    bool hasBoxDecorations() const { return m_bitfields.boxDecorationState() != NoBoxDecorations; }
538    bool backgroundIsKnownToBeObscured();
539    bool hasEntirelyFixedBackground() const;
540
541    bool needsLayout() const
542    {
543        return m_bitfields.needsLayout() || m_bitfields.normalChildNeedsLayout() || m_bitfields.posChildNeedsLayout()
544            || m_bitfields.needsSimplifiedNormalFlowLayout() || m_bitfields.needsPositionedMovementLayout();
545    }
546
547    bool selfNeedsLayout() const { return m_bitfields.needsLayout(); }
548    bool needsPositionedMovementLayout() const { return m_bitfields.needsPositionedMovementLayout(); }
549    bool needsPositionedMovementLayoutOnly() const
550    {
551        return m_bitfields.needsPositionedMovementLayout() && !m_bitfields.needsLayout() && !m_bitfields.normalChildNeedsLayout()
552            && !m_bitfields.posChildNeedsLayout() && !m_bitfields.needsSimplifiedNormalFlowLayout();
553    }
554
555    bool posChildNeedsLayout() const { return m_bitfields.posChildNeedsLayout(); }
556    bool needsSimplifiedNormalFlowLayout() const { return m_bitfields.needsSimplifiedNormalFlowLayout(); }
557    bool normalChildNeedsLayout() const { return m_bitfields.normalChildNeedsLayout(); }
558
559    bool preferredLogicalWidthsDirty() const { return m_bitfields.preferredLogicalWidthsDirty(); }
560
561    bool isSelectionBorder() const;
562
563    bool hasOverflowClip() const { return m_bitfields.hasOverflowClip(); }
564
565    bool hasTransform() const { return m_bitfields.hasTransform(); }
566
567    inline bool preservesNewline() const;
568
569    // The pseudo element style can be cached or uncached.  Use the cached method if the pseudo element doesn't respect
570    // any pseudo classes (and therefore has no concept of changing state).
571    RenderStyle* getCachedPseudoStyle(PseudoId, RenderStyle* parentStyle = 0) const;
572    PassRefPtr<RenderStyle> getUncachedPseudoStyle(const PseudoStyleRequest&, RenderStyle* parentStyle = 0, RenderStyle* ownStyle = 0) const;
573
574    virtual void updateDragState(bool dragOn);
575
576    RenderView& view() const { return *document().renderView(); };
577
578    // Returns true if this renderer is rooted, and optionally returns the hosting view (the root of the hierarchy).
579    bool isRooted(RenderView** = 0) const;
580
581    Node* node() const { return isAnonymous() ? 0 : &m_node; }
582    Node* nonPseudoNode() const { return isPseudoElement() ? 0 : node(); }
583
584    // Returns the styled node that caused the generation of this renderer.
585    // This is the same as node() except for renderers of :before and :after
586    // pseudo elements for which their parent node is returned.
587    Node* generatingNode() const { return isPseudoElement() ? generatingPseudoHostElement() : node(); }
588
589    Document& document() const { return m_node.document(); }
590    Frame& frame() const; // Defined in RenderView.h
591
592    bool hasOutlineAnnotation() const;
593    bool hasOutline() const { return style().hasOutline() || hasOutlineAnnotation(); }
594
595    // Returns the object containing this one. Can be different from parent for positioned elements.
596    // If repaintContainer and repaintContainerSkipped are not null, on return *repaintContainerSkipped
597    // is true if the renderer returned is an ancestor of repaintContainer.
598    RenderElement* container(const RenderLayerModelObject* repaintContainer = 0, bool* repaintContainerSkipped = 0) const;
599
600    RenderBoxModelObject* offsetParent() const;
601
602    void markContainingBlocksForLayout(bool scheduleRelayout = true, RenderElement* newRoot = 0);
603    void setNeedsLayout(MarkingBehavior = MarkContainingBlockChain);
604    void clearNeedsLayout();
605    void setPreferredLogicalWidthsDirty(bool, MarkingBehavior = MarkContainingBlockChain);
606    void invalidateContainerPreferredLogicalWidths();
607
608    void setNeedsLayoutAndPrefWidthsRecalc()
609    {
610        setNeedsLayout();
611        setPreferredLogicalWidthsDirty(true);
612    }
613
614    void setPositionState(EPosition position)
615    {
616        ASSERT((position != AbsolutePosition && position != FixedPosition) || isBox());
617        m_bitfields.setPositionedState(position);
618    }
619    void clearPositionedState() { m_bitfields.clearPositionedState(); }
620
621    void setFloating(bool b = true) { m_bitfields.setFloating(b); }
622    void setInline(bool b = true) { m_bitfields.setIsInline(b); }
623
624    void setHasBoxDecorations(bool = true);
625    void invalidateBackgroundObscurationStatus();
626    virtual bool computeBackgroundIsKnownToBeObscured() { return false; }
627
628    void setIsText() { ASSERT(!isBox()); m_bitfields.setIsTextOrRenderView(true); }
629    void setIsLineBreak() { m_bitfields.setIsLineBreak(true); }
630    void setIsBox() { m_bitfields.setIsBox(true); }
631    void setIsRenderView() { ASSERT(isBox()); m_bitfields.setIsTextOrRenderView(true); }
632    void setReplaced(bool b = true) { m_bitfields.setIsReplaced(b); }
633    void setHorizontalWritingMode(bool b = true) { m_bitfields.setHorizontalWritingMode(b); }
634    void setHasOverflowClip(bool b = true) { m_bitfields.setHasOverflowClip(b); }
635    void setHasLayer(bool b = true) { m_bitfields.setHasLayer(b); }
636    void setHasTransform(bool b = true) { m_bitfields.setHasTransform(b); }
637    void setHasReflection(bool b = true) { m_bitfields.setHasReflection(b); }
638
639    // Hook so that RenderTextControl can return the line height of its inner renderer.
640    // For other renderers, the value is the same as lineHeight(false).
641    virtual int innerLineHeight() const;
642
643    // used for element state updates that cannot be fixed with a
644    // repaint and do not need a relayout
645    virtual void updateFromElement() { }
646
647#if ENABLE(DASHBOARD_SUPPORT)
648    virtual void addAnnotatedRegions(Vector<AnnotatedRegionValue>&);
649    void collectAnnotatedRegions(Vector<AnnotatedRegionValue>&);
650#endif
651
652    bool isComposited() const;
653
654    bool hitTest(const HitTestRequest&, HitTestResult&, const HitTestLocation& locationInContainer, const LayoutPoint& accumulatedOffset, HitTestFilter = HitTestAll);
655    virtual void updateHitTestResult(HitTestResult&, const LayoutPoint&);
656    virtual bool nodeAtPoint(const HitTestRequest&, HitTestResult&, const HitTestLocation& locationInContainer, const LayoutPoint& accumulatedOffset, HitTestAction);
657
658    virtual VisiblePosition positionForPoint(const LayoutPoint&, const RenderRegion*);
659    VisiblePosition createVisiblePosition(int offset, EAffinity) const;
660    VisiblePosition createVisiblePosition(const Position&) const;
661
662    // returns the containing block level element for this element.
663    RenderBlock* containingBlock() const;
664
665    bool canContainFixedPositionObjects() const
666    {
667        return isRenderView() || (hasTransform() && isRenderBlock())
668                || isSVGForeignObject()
669                || isOutOfFlowRenderFlowThread();
670    }
671
672    // Convert the given local point to absolute coordinates
673    // FIXME: Temporary. If UseTransforms is true, take transforms into account. Eventually localToAbsolute() will always be transform-aware.
674    FloatPoint localToAbsolute(const FloatPoint& localPoint = FloatPoint(), MapCoordinatesFlags = 0) const;
675    FloatPoint absoluteToLocal(const FloatPoint&, MapCoordinatesFlags = 0) const;
676
677    // Convert a local quad to absolute coordinates, taking transforms into account.
678    FloatQuad localToAbsoluteQuad(const FloatQuad& quad, MapCoordinatesFlags mode = 0, bool* wasFixed = 0) const
679    {
680        return localToContainerQuad(quad, 0, mode, wasFixed);
681    }
682    // Convert an absolute quad to local coordinates.
683    FloatQuad absoluteToLocalQuad(const FloatQuad&, MapCoordinatesFlags mode = 0) const;
684
685    // Convert a local quad into the coordinate system of container, taking transforms into account.
686    FloatQuad localToContainerQuad(const FloatQuad&, const RenderLayerModelObject* repaintContainer, MapCoordinatesFlags = 0, bool* wasFixed = 0) const;
687    FloatPoint localToContainerPoint(const FloatPoint&, const RenderLayerModelObject* repaintContainer, MapCoordinatesFlags = 0, bool* wasFixed = 0) const;
688
689    // Return the offset from the container() renderer (excluding transforms). In multi-column layout,
690    // different offsets apply at different points, so return the offset that applies to the given point.
691    virtual LayoutSize offsetFromContainer(RenderObject*, const LayoutPoint&, bool* offsetDependsOnPoint = 0) const;
692    // Return the offset from an object up the container() chain. Asserts that none of the intermediate objects have transforms.
693    LayoutSize offsetFromAncestorContainer(RenderObject*) const;
694
695#if PLATFORM(IOS)
696    virtual void collectSelectionRects(Vector<SelectionRect>&, unsigned startOffset = 0, unsigned endOffset = std::numeric_limits<unsigned>::max());
697    virtual void absoluteQuadsForSelection(Vector<FloatQuad>& quads) const { absoluteQuads(quads); }
698#endif
699
700    virtual void absoluteRects(Vector<IntRect>&, const LayoutPoint&) const { }
701
702    // FIXME: useTransforms should go away eventually
703    IntRect absoluteBoundingBoxRect(bool useTransform = true) const;
704    IntRect absoluteBoundingBoxRectIgnoringTransforms() const { return absoluteBoundingBoxRect(false); }
705
706    // Build an array of quads in absolute coords for line boxes
707    virtual void absoluteQuads(Vector<FloatQuad>&, bool* /*wasFixed*/ = 0) const { }
708
709    virtual void absoluteFocusRingQuads(Vector<FloatQuad>&);
710
711    static FloatRect absoluteBoundingBoxRectForRange(const Range*);
712
713    // the rect that will be painted if this object is passed as the paintingRoot
714    LayoutRect paintingRootRect(LayoutRect& topLevelRect);
715
716    virtual LayoutUnit minPreferredLogicalWidth() const { return 0; }
717    virtual LayoutUnit maxPreferredLogicalWidth() const { return 0; }
718
719    RenderStyle& style() const;
720    RenderStyle& firstLineStyle() const;
721
722    // Anonymous blocks that are part of of a continuation chain will return their inline continuation's outline style instead.
723    // This is typically only relevant when repainting.
724    virtual const RenderStyle& outlineStyleForRepaint() const { return style(); }
725
726    virtual CursorDirective getCursor(const LayoutPoint&, Cursor&) const;
727
728    void getTextDecorationColors(int decorations, Color& underline, Color& overline, Color& linethrough, bool quirksMode = false, bool firstlineStyle = false);
729
730    // Return the RenderLayerModelObject in the container chain which is responsible for painting this object, or 0
731    // if painting is root-relative. This is the container that should be passed to the 'forRepaint'
732    // methods.
733    RenderLayerModelObject* containerForRepaint() const;
734    // Actually do the repaint of rect r for this object which has been computed in the coordinate space
735    // of repaintContainer. If repaintContainer is 0, repaint via the view.
736    void repaintUsingContainer(const RenderLayerModelObject* repaintContainer, const LayoutRect&, bool shouldClipToLayer = true) const;
737
738    // Repaint the entire object.  Called when, e.g., the color of a border changes, or when a border
739    // style changes.
740    void repaint() const;
741
742    // Repaint a specific subrectangle within a given object.  The rect |r| is in the object's coordinate space.
743    void repaintRectangle(const LayoutRect&, bool shouldClipToLayer = true) const;
744
745    // Repaint a slow repaint object, which, at this time, means we are repainting an object with background-attachment:fixed.
746    void repaintSlowRepaintObject() const;
747
748    bool checkForRepaintDuringLayout() const;
749
750    // Returns the rect that should be repainted whenever this object changes.  The rect is in the view's
751    // coordinate space.  This method deals with outlines and overflow.
752    LayoutRect absoluteClippedOverflowRect() const
753    {
754        return clippedOverflowRectForRepaint(0);
755    }
756    IntRect pixelSnappedAbsoluteClippedOverflowRect() const;
757    virtual LayoutRect clippedOverflowRectForRepaint(const RenderLayerModelObject* repaintContainer) const;
758    virtual LayoutRect rectWithOutlineForRepaint(const RenderLayerModelObject* repaintContainer, LayoutUnit outlineWidth) const;
759    virtual LayoutRect outlineBoundsForRepaint(const RenderLayerModelObject* /*repaintContainer*/, const RenderGeometryMap* = 0) const { return LayoutRect(); }
760
761    // Given a rect in the object's coordinate space, compute a rect suitable for repainting
762    // that rect in view coordinates.
763    void computeAbsoluteRepaintRect(LayoutRect& r, bool fixed = false) const
764    {
765        computeRectForRepaint(0, r, fixed);
766    }
767    // Given a rect in the object's coordinate space, compute a rect suitable for repainting
768    // that rect in the coordinate space of repaintContainer.
769    virtual void computeRectForRepaint(const RenderLayerModelObject* repaintContainer, LayoutRect&, bool fixed = false) const;
770    virtual void computeFloatRectForRepaint(const RenderLayerModelObject* repaintContainer, FloatRect& repaintRect, bool fixed = false) const;
771
772    virtual unsigned int length() const { return 1; }
773
774    bool isFloatingOrOutOfFlowPositioned() const { return (isFloating() || isOutOfFlowPositioned()); }
775
776    bool hasReflection() const { return m_bitfields.hasReflection(); }
777
778    // Applied as a "slop" to dirty rect checks during the outline painting phase's dirty-rect checks.
779    int maximalOutlineSize(PaintPhase) const;
780
781    enum SelectionState {
782        SelectionNone, // The object is not selected.
783        SelectionStart, // The object either contains the start of a selection run or is the start of a run
784        SelectionInside, // The object is fully encompassed by a selection run
785        SelectionEnd, // The object either contains the end of a selection run or is the end of a run
786        SelectionBoth // The object contains an entire run or is the sole selected object in that run
787    };
788
789    // The current selection state for an object.  For blocks, the state refers to the state of the leaf
790    // descendants (as described above in the SelectionState enum declaration).
791    SelectionState selectionState() const { return m_bitfields.selectionState(); }
792    virtual void setSelectionState(SelectionState state) { m_bitfields.setSelectionState(state); }
793    inline void setSelectionStateIfNeeded(SelectionState);
794    bool canUpdateSelectionOnRootLineBoxes();
795
796    // A single rectangle that encompasses all of the selected objects within this object.  Used to determine the tightest
797    // possible bounding box for the selection.
798    LayoutRect selectionRect(bool clipToVisibleContent = true) { return selectionRectForRepaint(0, clipToVisibleContent); }
799    virtual LayoutRect selectionRectForRepaint(const RenderLayerModelObject* /*repaintContainer*/, bool /*clipToVisibleContent*/ = true) { return LayoutRect(); }
800
801    virtual bool canBeSelectionLeaf() const { return false; }
802    bool hasSelectedChildren() const { return selectionState() != SelectionNone; }
803
804    // Obtains the selection colors that should be used when painting a selection.
805    Color selectionBackgroundColor() const;
806    Color selectionForegroundColor() const;
807    Color selectionEmphasisMarkColor() const;
808
809    // Whether or not a given block needs to paint selection gaps.
810    virtual bool shouldPaintSelectionGaps() const { return false; }
811
812    /**
813     * Returns the local coordinates of the caret within this render object.
814     * @param caretOffset zero-based offset determining position within the render object.
815     * @param extraWidthToEndOfLine optional out arg to give extra width to end of line -
816     * useful for character range rect computations
817     */
818    virtual LayoutRect localCaretRect(InlineBox*, int caretOffset, LayoutUnit* extraWidthToEndOfLine = 0);
819
820    // When performing a global document tear-down, the renderer of the document is cleared.  We use this
821    // as a hook to detect the case of document destruction and don't waste time doing unnecessary work.
822    bool documentBeingDestroyed() const;
823
824    void destroyAndCleanupAnonymousWrappers();
825    void destroy();
826
827    // Virtual function helpers for the deprecated Flexible Box Layout (display: -webkit-box).
828    virtual bool isDeprecatedFlexibleBox() const { return false; }
829    virtual bool isStretchingChildren() const { return false; }
830
831    // Virtual function helper for the new FlexibleBox Layout (display: -webkit-flex).
832    virtual bool isFlexibleBox() const { return false; }
833
834    bool isFlexibleBoxIncludingDeprecated() const
835    {
836        return isFlexibleBox() || isDeprecatedFlexibleBox();
837    }
838
839    virtual bool isCombineText() const { return false; }
840
841    virtual int caretMinOffset() const;
842    virtual int caretMaxOffset() const;
843
844    virtual int previousOffset(int current) const;
845    virtual int previousOffsetForBackwardDeletion(int current) const;
846    virtual int nextOffset(int current) const;
847
848    virtual void imageChanged(CachedImage*, const IntRect* = 0) override;
849    virtual void imageChanged(WrappedImagePtr, const IntRect* = 0) { }
850
851    SelectionSubtreeRoot& selectionRoot() const;
852    void selectionStartEnd(int& spos, int& epos) const;
853
854    void removeFromParent();
855
856    AnimationController& animation() const;
857
858    // Map points and quads through elements, potentially via 3d transforms. You should never need to call these directly; use
859    // localToAbsolute/absoluteToLocal methods instead.
860    virtual void mapLocalToContainer(const RenderLayerModelObject* repaintContainer, TransformState&, MapCoordinatesFlags = ApplyContainerFlip, bool* wasFixed = 0) const;
861    virtual void mapAbsoluteToLocalPoint(MapCoordinatesFlags, TransformState&) const;
862
863    // Pushes state onto RenderGeometryMap about how to map coordinates from this renderer to its container, or ancestorToStopAt (whichever is encountered first).
864    // Returns the renderer which was mapped to (container or ancestorToStopAt).
865    virtual const RenderObject* pushMappingToContainer(const RenderLayerModelObject* ancestorToStopAt, RenderGeometryMap&) const;
866
867    bool shouldUseTransformFromContainer(const RenderObject* container) const;
868    void getTransformFromContainer(const RenderObject* container, const LayoutSize& offsetInContainer, TransformationMatrix&) const;
869
870    virtual void addFocusRingRects(Vector<IntRect>&, const LayoutPoint& /* additionalOffset */, const RenderLayerModelObject* /* paintContainer */ = 0) { };
871
872    LayoutRect absoluteOutlineBounds() const
873    {
874        return outlineBoundsForRepaint(0);
875    }
876
877    RespectImageOrientationEnum shouldRespectImageOrientation() const;
878
879    void drawLineForBoxSide(GraphicsContext*, float x1, float y1, float x2, float y2, BoxSide, Color, EBorderStyle, float adjbw1, float adjbw2, bool antialias = false) const;
880protected:
881    void paintFocusRing(PaintInfo&, const LayoutPoint&, RenderStyle*);
882    void paintOutline(PaintInfo&, const LayoutRect&);
883    void addPDFURLRect(PaintInfo&, const LayoutPoint&);
884    Node& nodeForNonAnonymous() const { ASSERT(!isAnonymous()); return m_node; }
885
886    void adjustRectForOutlineAndShadow(LayoutRect&) const;
887
888    void clearLayoutRootIfNeeded() const;
889    virtual void willBeDestroyed();
890
891    virtual void insertedIntoTree();
892    virtual void willBeRemovedFromTree();
893
894    void setNeedsPositionedMovementLayoutBit(bool b) { m_bitfields.setNeedsPositionedMovementLayout(b); }
895    void setNormalChildNeedsLayoutBit(bool b) { m_bitfields.setNormalChildNeedsLayout(b); }
896    void setPosChildNeedsLayoutBit(bool b) { m_bitfields.setPosChildNeedsLayout(b); }
897    void setNeedsSimplifiedNormalFlowLayoutBit(bool b) { m_bitfields.setNeedsSimplifiedNormalFlowLayout(b); }
898
899private:
900    RenderFlowThread* locateFlowThreadContainingBlock() const;
901    RenderFlowThread* locateFlowThreadContainingBlockNoCache() const;
902
903    void removeFromRenderFlowThread();
904    void removeFromRenderFlowThreadRecursive(RenderFlowThread*);
905
906    Color selectionColor(int colorProperty) const;
907    PassRefPtr<RenderStyle> selectionPseudoStyle() const;
908
909    Node* generatingPseudoHostElement() const;
910
911    virtual bool isWBR() const { ASSERT_NOT_REACHED(); return false; }
912
913#ifndef NDEBUG
914    void checkBlockPositionedObjectsNeedLayout();
915#endif
916
917    Node& m_node;
918
919    RenderElement* m_parent;
920    RenderObject* m_previous;
921    RenderObject* m_next;
922
923#ifndef NDEBUG
924    bool m_hasAXObject             : 1;
925    bool m_setNeedsLayoutForbidden : 1;
926#endif
927
928#define ADD_BOOLEAN_BITFIELD(name, Name) \
929    private:\
930        unsigned m_##name : 1;\
931    public:\
932        bool name() const { return m_##name; }\
933        void set##Name(bool name) { m_##name = name; }\
934
935    class RenderObjectBitfields {
936        enum PositionedState {
937            IsStaticallyPositioned = 0,
938            IsRelativelyPositioned = 1,
939            IsOutOfFlowPositioned = 2,
940            IsStickyPositioned = 3
941        };
942
943    public:
944        RenderObjectBitfields(const Node& node)
945            : m_needsLayout(false)
946            , m_needsPositionedMovementLayout(false)
947            , m_normalChildNeedsLayout(false)
948            , m_posChildNeedsLayout(false)
949            , m_needsSimplifiedNormalFlowLayout(false)
950            , m_preferredLogicalWidthsDirty(false)
951            , m_floating(false)
952            , m_isAnonymous(node.isDocumentNode())
953            , m_isTextOrRenderView(false)
954            , m_isBox(false)
955            , m_isInline(true)
956            , m_isReplaced(false)
957            , m_isLineBreak(false)
958            , m_horizontalWritingMode(true)
959            , m_isDragging(false)
960            , m_hasLayer(false)
961            , m_hasOverflowClip(false)
962            , m_hasTransform(false)
963            , m_hasReflection(false)
964            , m_hasCounterNodeMap(false)
965            , m_everHadLayout(false)
966            , m_childrenInline(false)
967            , m_positionedState(IsStaticallyPositioned)
968            , m_selectionState(SelectionNone)
969            , m_flowThreadState(NotInsideFlowThread)
970            , m_boxDecorationState(NoBoxDecorations)
971        {
972        }
973
974        // 32 bits have been used here. There are no bits available.
975        ADD_BOOLEAN_BITFIELD(needsLayout, NeedsLayout);
976        ADD_BOOLEAN_BITFIELD(needsPositionedMovementLayout, NeedsPositionedMovementLayout);
977        ADD_BOOLEAN_BITFIELD(normalChildNeedsLayout, NormalChildNeedsLayout);
978        ADD_BOOLEAN_BITFIELD(posChildNeedsLayout, PosChildNeedsLayout);
979        ADD_BOOLEAN_BITFIELD(needsSimplifiedNormalFlowLayout, NeedsSimplifiedNormalFlowLayout);
980        ADD_BOOLEAN_BITFIELD(preferredLogicalWidthsDirty, PreferredLogicalWidthsDirty);
981        ADD_BOOLEAN_BITFIELD(floating, Floating);
982
983        ADD_BOOLEAN_BITFIELD(isAnonymous, IsAnonymous);
984        ADD_BOOLEAN_BITFIELD(isTextOrRenderView, IsTextOrRenderView);
985        ADD_BOOLEAN_BITFIELD(isBox, IsBox);
986        ADD_BOOLEAN_BITFIELD(isInline, IsInline);
987        ADD_BOOLEAN_BITFIELD(isReplaced, IsReplaced);
988        ADD_BOOLEAN_BITFIELD(isLineBreak, IsLineBreak);
989        ADD_BOOLEAN_BITFIELD(horizontalWritingMode, HorizontalWritingMode);
990        ADD_BOOLEAN_BITFIELD(isDragging, IsDragging);
991
992        ADD_BOOLEAN_BITFIELD(hasLayer, HasLayer);
993        ADD_BOOLEAN_BITFIELD(hasOverflowClip, HasOverflowClip); // Set in the case of overflow:auto/scroll/hidden
994        ADD_BOOLEAN_BITFIELD(hasTransform, HasTransform);
995        ADD_BOOLEAN_BITFIELD(hasReflection, HasReflection);
996
997        ADD_BOOLEAN_BITFIELD(hasCounterNodeMap, HasCounterNodeMap);
998        ADD_BOOLEAN_BITFIELD(everHadLayout, EverHadLayout);
999
1000        // from RenderBlock
1001        ADD_BOOLEAN_BITFIELD(childrenInline, ChildrenInline);
1002
1003    private:
1004        unsigned m_positionedState : 2; // PositionedState
1005        unsigned m_selectionState : 3; // SelectionState
1006        unsigned m_flowThreadState : 2; // FlowThreadState
1007        unsigned m_boxDecorationState : 2; // BoxDecorationState
1008
1009    public:
1010        bool isOutOfFlowPositioned() const { return m_positionedState == IsOutOfFlowPositioned; }
1011        bool isRelPositioned() const { return m_positionedState == IsRelativelyPositioned; }
1012        bool isStickyPositioned() const { return m_positionedState == IsStickyPositioned; }
1013        bool isPositioned() const { return m_positionedState != IsStaticallyPositioned; }
1014
1015        void setPositionedState(int positionState)
1016        {
1017            // This mask maps FixedPosition and AbsolutePosition to IsOutOfFlowPositioned, saving one bit.
1018            m_positionedState = static_cast<PositionedState>(positionState & 0x3);
1019        }
1020        void clearPositionedState() { m_positionedState = StaticPosition; }
1021
1022        ALWAYS_INLINE SelectionState selectionState() const { return static_cast<SelectionState>(m_selectionState); }
1023        ALWAYS_INLINE void setSelectionState(SelectionState selectionState) { m_selectionState = selectionState; }
1024
1025        ALWAYS_INLINE FlowThreadState flowThreadState() const { return static_cast<FlowThreadState>(m_flowThreadState); }
1026        ALWAYS_INLINE void setFlowThreadState(FlowThreadState flowThreadState) { m_flowThreadState = flowThreadState; }
1027
1028        ALWAYS_INLINE BoxDecorationState boxDecorationState() const { return static_cast<BoxDecorationState>(m_boxDecorationState); }
1029        ALWAYS_INLINE void setBoxDecorationState(BoxDecorationState boxDecorationState) { m_boxDecorationState = boxDecorationState; }
1030    };
1031
1032#undef ADD_BOOLEAN_BITFIELD
1033
1034    RenderObjectBitfields m_bitfields;
1035
1036    void setIsDragging(bool b) { m_bitfields.setIsDragging(b); }
1037    void setEverHadLayout(bool b) { m_bitfields.setEverHadLayout(b); }
1038};
1039
1040template <typename Type> bool isRendererOfType(const RenderObject&);
1041template <> inline bool isRendererOfType<const RenderObject>(const RenderObject&) { return true; }
1042
1043inline Frame& RenderObject::frame() const
1044{
1045    return *document().frame();
1046}
1047
1048inline AnimationController& RenderObject::animation() const
1049{
1050    return frame().animation();
1051}
1052
1053inline bool RenderObject::documentBeingDestroyed() const
1054{
1055    return document().renderTreeBeingDestroyed();
1056}
1057
1058inline bool RenderObject::isBeforeContent() const
1059{
1060    // Text nodes don't have their own styles, so ignore the style on a text node.
1061    if (isText())
1062        return false;
1063    if (style().styleType() != BEFORE)
1064        return false;
1065    return true;
1066}
1067
1068inline bool RenderObject::isAfterContent() const
1069{
1070    // Text nodes don't have their own styles, so ignore the style on a text node.
1071    if (isText())
1072        return false;
1073    if (style().styleType() != AFTER)
1074        return false;
1075    return true;
1076}
1077
1078inline bool RenderObject::isBeforeOrAfterContent() const
1079{
1080    return isBeforeContent() || isAfterContent();
1081}
1082
1083inline void RenderObject::setNeedsLayout(MarkingBehavior markParents)
1084{
1085    ASSERT(!isSetNeedsLayoutForbidden());
1086    if (m_bitfields.needsLayout())
1087        return;
1088    m_bitfields.setNeedsLayout(true);
1089    if (markParents == MarkContainingBlockChain)
1090        markContainingBlocksForLayout();
1091    if (hasLayer())
1092        setLayerNeedsFullRepaint();
1093}
1094
1095inline bool RenderObject::preservesNewline() const
1096{
1097    if (isSVGInlineText())
1098        return false;
1099
1100    return style().preserveNewline();
1101}
1102
1103inline void RenderObject::setSelectionStateIfNeeded(SelectionState state)
1104{
1105    if (selectionState() == state)
1106        return;
1107
1108    setSelectionState(state);
1109}
1110
1111inline void RenderObject::setHasBoxDecorations(bool b)
1112{
1113    if (!b) {
1114        m_bitfields.setBoxDecorationState(NoBoxDecorations);
1115        return;
1116    }
1117    if (hasBoxDecorations())
1118        return;
1119    m_bitfields.setBoxDecorationState(HasBoxDecorationsAndBackgroundObscurationStatusInvalid);
1120}
1121
1122inline void RenderObject::invalidateBackgroundObscurationStatus()
1123{
1124    if (!hasBoxDecorations())
1125        return;
1126    m_bitfields.setBoxDecorationState(HasBoxDecorationsAndBackgroundObscurationStatusInvalid);
1127}
1128
1129inline bool RenderObject::backgroundIsKnownToBeObscured()
1130{
1131    if (m_bitfields.boxDecorationState() == HasBoxDecorationsAndBackgroundObscurationStatusInvalid) {
1132        BoxDecorationState boxDecorationState = computeBackgroundIsKnownToBeObscured() ? HasBoxDecorationsAndBackgroundIsKnownToBeObscured : HasBoxDecorationsAndBackgroundMayBeVisible;
1133        m_bitfields.setBoxDecorationState(boxDecorationState);
1134    }
1135    return m_bitfields.boxDecorationState() == HasBoxDecorationsAndBackgroundIsKnownToBeObscured;
1136}
1137
1138#define RENDER_OBJECT_TYPE_CASTS(ToValueTypeName, predicate) \
1139    template <> inline bool isRendererOfType<const ToValueTypeName>(const RenderObject& renderer) { return renderer.predicate; } \
1140    TYPE_CASTS_BASE(ToValueTypeName, RenderObject, renderer, isRendererOfType<const ToValueTypeName>(*renderer), isRendererOfType<const ToValueTypeName>(renderer))
1141
1142} // namespace WebCore
1143
1144#ifndef NDEBUG
1145// Outside the WebCore namespace for ease of invocation from gdb.
1146void showTree(const WebCore::RenderObject*);
1147void showLineTree(const WebCore::RenderObject*);
1148void showRenderTree(const WebCore::RenderObject* object1);
1149// We don't make object2 an optional parameter so that showRenderTree
1150// can be called from gdb easily.
1151void showRenderTree(const WebCore::RenderObject* object1, const WebCore::RenderObject* object2);
1152#endif
1153
1154#endif // RenderObject_h
1155