1/*
2 * Copyright (C) 1999 Antti Koivisto (koivisto@kde.org)
3 * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
4 * Copyright (C) 2011 Adobe Systems Incorporated. All rights reserved.
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Library General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
10 *
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14 * Library General Public License for more details.
15 *
16 * You should have received a copy of the GNU Library General Public License
17 * along with this library; see the file COPYING.LIB.  If not, write to
18 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
19 * Boston, MA 02110-1301, USA.
20 *
21 */
22
23#include "config.h"
24#include "core/rendering/style/RenderStyle.h"
25
26#include <algorithm>
27#include "core/css/resolver/StyleResolver.h"
28#include "core/rendering/RenderTheme.h"
29#include "core/rendering/TextAutosizer.h"
30#include "core/rendering/style/AppliedTextDecoration.h"
31#include "core/rendering/style/ContentData.h"
32#include "core/rendering/style/QuotesData.h"
33#include "core/rendering/style/ShadowList.h"
34#include "core/rendering/style/StyleImage.h"
35#include "core/rendering/style/StyleInheritedData.h"
36#include "platform/LengthFunctions.h"
37#include "platform/RuntimeEnabledFeatures.h"
38#include "platform/fonts/Font.h"
39#include "platform/fonts/FontSelector.h"
40#include "platform/geometry/FloatRoundedRect.h"
41#include "wtf/MathExtras.h"
42
43using namespace std;
44
45namespace WebCore {
46
47struct SameSizeAsBorderValue {
48    RGBA32 m_color;
49    unsigned m_width;
50};
51
52COMPILE_ASSERT(sizeof(BorderValue) == sizeof(SameSizeAsBorderValue), BorderValue_should_not_grow);
53
54struct SameSizeAsRenderStyle : public RefCounted<SameSizeAsRenderStyle> {
55    void* dataRefs[7];
56    void* ownPtrs[1];
57    void* dataRefSvgStyle;
58
59    struct InheritedFlags {
60        unsigned m_bitfields[2];
61    } inherited_flags;
62
63    struct NonInheritedFlags {
64        unsigned m_bitfields[2];
65    } noninherited_flags;
66};
67
68COMPILE_ASSERT(sizeof(RenderStyle) == sizeof(SameSizeAsRenderStyle), RenderStyle_should_stay_small);
69
70inline RenderStyle* defaultStyle()
71{
72    DEFINE_STATIC_REF(RenderStyle, s_defaultStyle, (RenderStyle::createDefaultStyle()));
73    return s_defaultStyle;
74}
75
76PassRefPtr<RenderStyle> RenderStyle::create()
77{
78    return adoptRef(new RenderStyle());
79}
80
81PassRefPtr<RenderStyle> RenderStyle::createDefaultStyle()
82{
83    return adoptRef(new RenderStyle(DefaultStyle));
84}
85
86PassRefPtr<RenderStyle> RenderStyle::createAnonymousStyleWithDisplay(const RenderStyle* parentStyle, EDisplay display)
87{
88    RefPtr<RenderStyle> newStyle = RenderStyle::create();
89    newStyle->inheritFrom(parentStyle);
90    newStyle->inheritUnicodeBidiFrom(parentStyle);
91    newStyle->setDisplay(display);
92    return newStyle;
93}
94
95PassRefPtr<RenderStyle> RenderStyle::clone(const RenderStyle* other)
96{
97    return adoptRef(new RenderStyle(*other));
98}
99
100ALWAYS_INLINE RenderStyle::RenderStyle()
101    : m_box(defaultStyle()->m_box)
102    , visual(defaultStyle()->visual)
103    , m_background(defaultStyle()->m_background)
104    , surround(defaultStyle()->surround)
105    , rareNonInheritedData(defaultStyle()->rareNonInheritedData)
106    , rareInheritedData(defaultStyle()->rareInheritedData)
107    , inherited(defaultStyle()->inherited)
108    , m_svgStyle(defaultStyle()->m_svgStyle)
109{
110    setBitDefaults(); // Would it be faster to copy this from the default style?
111    COMPILE_ASSERT((sizeof(InheritedFlags) <= 8), InheritedFlags_does_not_grow);
112    COMPILE_ASSERT((sizeof(NonInheritedFlags) <= 8), NonInheritedFlags_does_not_grow);
113}
114
115ALWAYS_INLINE RenderStyle::RenderStyle(DefaultStyleTag)
116{
117    setBitDefaults();
118
119    m_box.init();
120    visual.init();
121    m_background.init();
122    surround.init();
123    rareNonInheritedData.init();
124    rareNonInheritedData.access()->m_deprecatedFlexibleBox.init();
125    rareNonInheritedData.access()->m_flexibleBox.init();
126    rareNonInheritedData.access()->m_marquee.init();
127    rareNonInheritedData.access()->m_multiCol.init();
128    rareNonInheritedData.access()->m_transform.init();
129    rareNonInheritedData.access()->m_willChange.init();
130    rareNonInheritedData.access()->m_filter.init();
131    rareNonInheritedData.access()->m_grid.init();
132    rareNonInheritedData.access()->m_gridItem.init();
133    rareInheritedData.init();
134    inherited.init();
135    m_svgStyle.init();
136}
137
138ALWAYS_INLINE RenderStyle::RenderStyle(const RenderStyle& o)
139    : RefCounted<RenderStyle>()
140    , m_box(o.m_box)
141    , visual(o.visual)
142    , m_background(o.m_background)
143    , surround(o.surround)
144    , rareNonInheritedData(o.rareNonInheritedData)
145    , rareInheritedData(o.rareInheritedData)
146    , inherited(o.inherited)
147    , m_svgStyle(o.m_svgStyle)
148    , inherited_flags(o.inherited_flags)
149    , noninherited_flags(o.noninherited_flags)
150{
151}
152
153static StyleRecalcChange diffPseudoStyles(const RenderStyle* oldStyle, const RenderStyle* newStyle)
154{
155    // If the pseudoStyles have changed, we want any StyleRecalcChange that is not NoChange
156    // because setStyle will do the right thing with anything else.
157    if (!oldStyle->hasAnyPublicPseudoStyles())
158        return NoChange;
159    for (PseudoId pseudoId = FIRST_PUBLIC_PSEUDOID; pseudoId < FIRST_INTERNAL_PSEUDOID; pseudoId = static_cast<PseudoId>(pseudoId + 1)) {
160        if (!oldStyle->hasPseudoStyle(pseudoId))
161            continue;
162        RenderStyle* newPseudoStyle = newStyle->getCachedPseudoStyle(pseudoId);
163        if (!newPseudoStyle)
164            return NoInherit;
165        RenderStyle* oldPseudoStyle = oldStyle->getCachedPseudoStyle(pseudoId);
166        if (oldPseudoStyle && *oldPseudoStyle != *newPseudoStyle)
167            return NoInherit;
168    }
169    return NoChange;
170}
171
172StyleRecalcChange RenderStyle::stylePropagationDiff(const RenderStyle* oldStyle, const RenderStyle* newStyle)
173{
174    if ((!oldStyle && newStyle) || (oldStyle && !newStyle))
175        return Reattach;
176
177    if (!oldStyle && !newStyle)
178        return NoChange;
179
180    if (oldStyle->display() != newStyle->display()
181        || oldStyle->hasPseudoStyle(FIRST_LETTER) != newStyle->hasPseudoStyle(FIRST_LETTER)
182        || oldStyle->columnSpan() != newStyle->columnSpan()
183        || !oldStyle->contentDataEquivalent(newStyle)
184        || oldStyle->hasTextCombine() != newStyle->hasTextCombine())
185        return Reattach;
186
187    if (*oldStyle == *newStyle)
188        return diffPseudoStyles(oldStyle, newStyle);
189
190    if (oldStyle->inheritedNotEqual(newStyle)
191        || oldStyle->hasExplicitlyInheritedProperties()
192        || newStyle->hasExplicitlyInheritedProperties())
193        return Inherit;
194
195    return NoInherit;
196}
197
198void RenderStyle::inheritFrom(const RenderStyle* inheritParent, IsAtShadowBoundary isAtShadowBoundary)
199{
200    if (isAtShadowBoundary == AtShadowBoundary) {
201        // Even if surrounding content is user-editable, shadow DOM should act as a single unit, and not necessarily be editable
202        EUserModify currentUserModify = userModify();
203        rareInheritedData = inheritParent->rareInheritedData;
204        setUserModify(currentUserModify);
205    } else
206        rareInheritedData = inheritParent->rareInheritedData;
207    inherited = inheritParent->inherited;
208    inherited_flags = inheritParent->inherited_flags;
209    if (m_svgStyle != inheritParent->m_svgStyle)
210        m_svgStyle.access()->inheritFrom(inheritParent->m_svgStyle.get());
211}
212
213void RenderStyle::copyNonInheritedFrom(const RenderStyle* other)
214{
215    m_box = other->m_box;
216    visual = other->visual;
217    m_background = other->m_background;
218    surround = other->surround;
219    rareNonInheritedData = other->rareNonInheritedData;
220    // The flags are copied one-by-one because noninherited_flags contains a bunch of stuff other than real style data.
221    noninherited_flags._effectiveDisplay = other->noninherited_flags._effectiveDisplay;
222    noninherited_flags._originalDisplay = other->noninherited_flags._originalDisplay;
223    noninherited_flags._overflowX = other->noninherited_flags._overflowX;
224    noninherited_flags._overflowY = other->noninherited_flags._overflowY;
225    noninherited_flags._vertical_align = other->noninherited_flags._vertical_align;
226    noninherited_flags._clear = other->noninherited_flags._clear;
227    noninherited_flags._position = other->noninherited_flags._position;
228    noninherited_flags._floating = other->noninherited_flags._floating;
229    noninherited_flags._table_layout = other->noninherited_flags._table_layout;
230    noninherited_flags._unicodeBidi = other->noninherited_flags._unicodeBidi;
231    noninherited_flags._page_break_before = other->noninherited_flags._page_break_before;
232    noninherited_flags._page_break_after = other->noninherited_flags._page_break_after;
233    noninherited_flags._page_break_inside = other->noninherited_flags._page_break_inside;
234    noninherited_flags.explicitInheritance = other->noninherited_flags.explicitInheritance;
235    noninherited_flags.currentColor = other->noninherited_flags.currentColor;
236    noninherited_flags.hasViewportUnits = other->noninherited_flags.hasViewportUnits;
237    if (m_svgStyle != other->m_svgStyle)
238        m_svgStyle.access()->copyNonInheritedFrom(other->m_svgStyle.get());
239    ASSERT(zoom() == initialZoom());
240}
241
242bool RenderStyle::operator==(const RenderStyle& o) const
243{
244    // compare everything except the pseudoStyle pointer
245    return inherited_flags == o.inherited_flags
246        && noninherited_flags == o.noninherited_flags
247        && m_box == o.m_box
248        && visual == o.visual
249        && m_background == o.m_background
250        && surround == o.surround
251        && rareNonInheritedData == o.rareNonInheritedData
252        && rareInheritedData == o.rareInheritedData
253        && inherited == o.inherited
254        && m_svgStyle == o.m_svgStyle;
255}
256
257bool RenderStyle::isStyleAvailable() const
258{
259    return this != StyleResolver::styleNotYetAvailable();
260}
261
262bool RenderStyle::hasUniquePseudoStyle() const
263{
264    if (!m_cachedPseudoStyles || styleType() != NOPSEUDO)
265        return false;
266
267    for (size_t i = 0; i < m_cachedPseudoStyles->size(); ++i) {
268        RenderStyle* pseudoStyle = m_cachedPseudoStyles->at(i).get();
269        if (pseudoStyle->unique())
270            return true;
271    }
272
273    return false;
274}
275
276RenderStyle* RenderStyle::getCachedPseudoStyle(PseudoId pid) const
277{
278    if (!m_cachedPseudoStyles || !m_cachedPseudoStyles->size())
279        return 0;
280
281    if (styleType() != NOPSEUDO)
282        return 0;
283
284    for (size_t i = 0; i < m_cachedPseudoStyles->size(); ++i) {
285        RenderStyle* pseudoStyle = m_cachedPseudoStyles->at(i).get();
286        if (pseudoStyle->styleType() == pid)
287            return pseudoStyle;
288    }
289
290    return 0;
291}
292
293RenderStyle* RenderStyle::addCachedPseudoStyle(PassRefPtr<RenderStyle> pseudo)
294{
295    if (!pseudo)
296        return 0;
297
298    ASSERT(pseudo->styleType() > NOPSEUDO);
299
300    RenderStyle* result = pseudo.get();
301
302    if (!m_cachedPseudoStyles)
303        m_cachedPseudoStyles = adoptPtr(new PseudoStyleCache);
304
305    m_cachedPseudoStyles->append(pseudo);
306
307    return result;
308}
309
310void RenderStyle::removeCachedPseudoStyle(PseudoId pid)
311{
312    if (!m_cachedPseudoStyles)
313        return;
314    for (size_t i = 0; i < m_cachedPseudoStyles->size(); ++i) {
315        RenderStyle* pseudoStyle = m_cachedPseudoStyles->at(i).get();
316        if (pseudoStyle->styleType() == pid) {
317            m_cachedPseudoStyles->remove(i);
318            return;
319        }
320    }
321}
322
323bool RenderStyle::inheritedNotEqual(const RenderStyle* other) const
324{
325    return inherited_flags != other->inherited_flags
326           || inherited != other->inherited
327           || m_svgStyle->inheritedNotEqual(other->m_svgStyle.get())
328           || rareInheritedData != other->rareInheritedData;
329}
330
331bool RenderStyle::inheritedDataShared(const RenderStyle* other) const
332{
333    // This is a fast check that only looks if the data structures are shared.
334    return inherited_flags == other->inherited_flags
335        && inherited.get() == other->inherited.get()
336        && m_svgStyle.get() == other->m_svgStyle.get()
337        && rareInheritedData.get() == other->rareInheritedData.get();
338}
339
340static bool positionedObjectMovedOnly(const LengthBox& a, const LengthBox& b, const Length& width)
341{
342    // If any unit types are different, then we can't guarantee
343    // that this was just a movement.
344    if (a.left().type() != b.left().type()
345        || a.right().type() != b.right().type()
346        || a.top().type() != b.top().type()
347        || a.bottom().type() != b.bottom().type())
348        return false;
349
350    // Only one unit can be non-auto in the horizontal direction and
351    // in the vertical direction.  Otherwise the adjustment of values
352    // is changing the size of the box.
353    if (!a.left().isIntrinsicOrAuto() && !a.right().isIntrinsicOrAuto())
354        return false;
355    if (!a.top().isIntrinsicOrAuto() && !a.bottom().isIntrinsicOrAuto())
356        return false;
357    // If our width is auto and left or right is specified and changed then this
358    // is not just a movement - we need to resize to our container.
359    if (width.isIntrinsicOrAuto()
360        && ((!a.left().isIntrinsicOrAuto() && a.left() != b.left())
361            || (!a.right().isIntrinsicOrAuto() && a.right() != b.right())))
362        return false;
363
364    // One of the units is fixed or percent in both directions and stayed
365    // that way in the new style.  Therefore all we are doing is moving.
366    return true;
367}
368
369StyleDifference RenderStyle::visualInvalidationDiff(const RenderStyle& other, unsigned& changedContextSensitiveProperties) const
370{
371    // Note, we use .get() on each DataRef below because DataRef::operator== will do a deep
372    // compare, which is duplicate work when we're going to compare each property inside
373    // this function anyway.
374
375    StyleDifference diff;
376    if (m_svgStyle.get() != other.m_svgStyle.get())
377        diff = m_svgStyle->diff(other.m_svgStyle.get());
378
379    if ((!diff.needsFullLayout() || !diff.needsRepaint()) && diffNeedsFullLayoutAndRepaint(other)) {
380        diff.setNeedsFullLayout();
381        diff.setNeedsRepaintObject();
382    }
383
384    if (!diff.needsFullLayout() && diffNeedsFullLayout(other))
385        diff.setNeedsFullLayout();
386
387    if (!diff.needsFullLayout() && position() != StaticPosition && surround->offset != other.surround->offset) {
388        // Optimize for the case where a positioned layer is moving but not changing size.
389        if ((position() == AbsolutePosition || position() == FixedPosition)
390            && positionedObjectMovedOnly(surround->offset, other.surround->offset, m_box->width())) {
391            diff.setNeedsPositionedMovementLayout();
392        } else {
393            // FIXME: We would like to use SimplifiedLayout for relative positioning, but we can't quite do that yet.
394            // We need to make sure SimplifiedLayout can operate correctly on RenderInlines (we will need
395            // to add a selfNeedsSimplifiedLayout bit in order to not get confused and taint every line).
396            diff.setNeedsFullLayout();
397        }
398    }
399
400    if (diffNeedsRepaintLayer(other))
401        diff.setNeedsRepaintLayer();
402    else if (diffNeedsRepaintObject(other))
403        diff.setNeedsRepaintObject();
404
405    changedContextSensitiveProperties = computeChangedContextSensitiveProperties(other, diff);
406
407    if (diff.hasNoChange() && diffNeedsRecompositeLayer(other))
408        diff.setNeedsRecompositeLayer();
409
410    // Cursors are not checked, since they will be set appropriately in response to mouse events,
411    // so they don't need to cause any repaint or layout.
412
413    // Animations don't need to be checked either. We always set the new style on the RenderObject, so we will get a chance to fire off
414    // the resulting transition properly.
415
416    return diff;
417}
418
419bool RenderStyle::diffNeedsFullLayoutAndRepaint(const RenderStyle& other) const
420{
421    // FIXME: Not all cases in this method need both full layout and repaint.
422    // Should move cases into diffNeedsFullLayout() if
423    // - don't need repaint at all;
424    // - or the renderer knows how to exactly repaint caused by the layout change
425    //   instead of forced full repaint.
426
427    if (m_box.get() != other.m_box.get()) {
428        if (m_box->width() != other.m_box->width()
429            || m_box->minWidth() != other.m_box->minWidth()
430            || m_box->maxWidth() != other.m_box->maxWidth()
431            || m_box->height() != other.m_box->height()
432            || m_box->minHeight() != other.m_box->minHeight()
433            || m_box->maxHeight() != other.m_box->maxHeight())
434            return true;
435
436        if (m_box->verticalAlign() != other.m_box->verticalAlign())
437            return true;
438
439        if (m_box->boxSizing() != other.m_box->boxSizing())
440            return true;
441    }
442
443    if (surround.get() != other.surround.get()) {
444        if (surround->margin != other.surround->margin)
445            return true;
446
447        if (surround->padding != other.surround->padding)
448            return true;
449
450        // If our border widths change, then we need to layout. Other changes to borders only necessitate a repaint.
451        if (borderLeftWidth() != other.borderLeftWidth()
452            || borderTopWidth() != other.borderTopWidth()
453            || borderBottomWidth() != other.borderBottomWidth()
454            || borderRightWidth() != other.borderRightWidth())
455            return true;
456    }
457
458    if (rareNonInheritedData.get() != other.rareNonInheritedData.get()) {
459        if (rareNonInheritedData->m_appearance != other.rareNonInheritedData->m_appearance
460            || rareNonInheritedData->marginBeforeCollapse != other.rareNonInheritedData->marginBeforeCollapse
461            || rareNonInheritedData->marginAfterCollapse != other.rareNonInheritedData->marginAfterCollapse
462            || rareNonInheritedData->lineClamp != other.rareNonInheritedData->lineClamp
463            || rareNonInheritedData->textOverflow != other.rareNonInheritedData->textOverflow
464            || rareNonInheritedData->m_wrapFlow != other.rareNonInheritedData->m_wrapFlow
465            || rareNonInheritedData->m_wrapThrough != other.rareNonInheritedData->m_wrapThrough
466            || rareNonInheritedData->m_shapeMargin != other.rareNonInheritedData->m_shapeMargin
467            || rareNonInheritedData->m_order != other.rareNonInheritedData->m_order
468            || rareNonInheritedData->m_alignContent != other.rareNonInheritedData->m_alignContent
469            || rareNonInheritedData->m_alignItems != other.rareNonInheritedData->m_alignItems
470            || rareNonInheritedData->m_alignSelf != other.rareNonInheritedData->m_alignSelf
471            || rareNonInheritedData->m_justifyContent != other.rareNonInheritedData->m_justifyContent
472            || rareNonInheritedData->m_grid.get() != other.rareNonInheritedData->m_grid.get()
473            || rareNonInheritedData->m_gridItem.get() != other.rareNonInheritedData->m_gridItem.get()
474            || rareNonInheritedData->m_textCombine != other.rareNonInheritedData->m_textCombine
475            || rareNonInheritedData->hasFilters() != other.rareNonInheritedData->hasFilters())
476            return true;
477
478        if (rareNonInheritedData->m_deprecatedFlexibleBox.get() != other.rareNonInheritedData->m_deprecatedFlexibleBox.get()
479            && *rareNonInheritedData->m_deprecatedFlexibleBox.get() != *other.rareNonInheritedData->m_deprecatedFlexibleBox.get())
480            return true;
481
482        if (rareNonInheritedData->m_flexibleBox.get() != other.rareNonInheritedData->m_flexibleBox.get()
483            && *rareNonInheritedData->m_flexibleBox.get() != *other.rareNonInheritedData->m_flexibleBox.get())
484            return true;
485
486        // FIXME: We should add an optimized form of layout that just recomputes visual overflow.
487        if (!rareNonInheritedData->shadowDataEquivalent(*other.rareNonInheritedData.get()))
488            return true;
489
490        if (!rareNonInheritedData->reflectionDataEquivalent(*other.rareNonInheritedData.get()))
491            return true;
492
493        if (rareNonInheritedData->m_multiCol.get() != other.rareNonInheritedData->m_multiCol.get()
494            && *rareNonInheritedData->m_multiCol.get() != *other.rareNonInheritedData->m_multiCol.get())
495            return true;
496
497        // If the counter directives change, trigger a relayout to re-calculate counter values and rebuild the counter node tree.
498        const CounterDirectiveMap* mapA = rareNonInheritedData->m_counterDirectives.get();
499        const CounterDirectiveMap* mapB = other.rareNonInheritedData->m_counterDirectives.get();
500        if (!(mapA == mapB || (mapA && mapB && *mapA == *mapB)))
501            return true;
502
503        // We only need do layout for opacity changes if adding or losing opacity could trigger a change
504        // in us being a stacking context.
505        if (hasAutoZIndex() != other.hasAutoZIndex() && rareNonInheritedData->hasOpacity() != other.rareNonInheritedData->hasOpacity()) {
506            // FIXME: We would like to use SimplifiedLayout here, but we can't quite do that yet.
507            // We need to make sure SimplifiedLayout can operate correctly on RenderInlines (we will need
508            // to add a selfNeedsSimplifiedLayout bit in order to not get confused and taint every line).
509            // In addition we need to solve the floating object issue when layers come and go. Right now
510            // a full layout is necessary to keep floating object lists sane.
511            return true;
512        }
513    }
514
515    if (rareInheritedData.get() != other.rareInheritedData.get()) {
516        if (rareInheritedData->highlight != other.rareInheritedData->highlight
517            || rareInheritedData->indent != other.rareInheritedData->indent
518            || rareInheritedData->m_textAlignLast != other.rareInheritedData->m_textAlignLast
519            || rareInheritedData->m_textIndentLine != other.rareInheritedData->m_textIndentLine
520            || rareInheritedData->m_effectiveZoom != other.rareInheritedData->m_effectiveZoom
521            || rareInheritedData->wordBreak != other.rareInheritedData->wordBreak
522            || rareInheritedData->overflowWrap != other.rareInheritedData->overflowWrap
523            || rareInheritedData->lineBreak != other.rareInheritedData->lineBreak
524            || rareInheritedData->textSecurity != other.rareInheritedData->textSecurity
525            || rareInheritedData->hyphens != other.rareInheritedData->hyphens
526            || rareInheritedData->hyphenationLimitBefore != other.rareInheritedData->hyphenationLimitBefore
527            || rareInheritedData->hyphenationLimitAfter != other.rareInheritedData->hyphenationLimitAfter
528            || rareInheritedData->hyphenationString != other.rareInheritedData->hyphenationString
529            || rareInheritedData->locale != other.rareInheritedData->locale
530            || rareInheritedData->m_rubyPosition != other.rareInheritedData->m_rubyPosition
531            || rareInheritedData->textEmphasisMark != other.rareInheritedData->textEmphasisMark
532            || rareInheritedData->textEmphasisPosition != other.rareInheritedData->textEmphasisPosition
533            || rareInheritedData->textEmphasisCustomMark != other.rareInheritedData->textEmphasisCustomMark
534            || rareInheritedData->m_textJustify != other.rareInheritedData->m_textJustify
535            || rareInheritedData->m_textOrientation != other.rareInheritedData->m_textOrientation
536            || rareInheritedData->m_tabSize != other.rareInheritedData->m_tabSize
537            || rareInheritedData->m_lineBoxContain != other.rareInheritedData->m_lineBoxContain
538            || rareInheritedData->listStyleImage != other.rareInheritedData->listStyleImage
539            || rareInheritedData->textStrokeWidth != other.rareInheritedData->textStrokeWidth)
540            return true;
541
542        if (!rareInheritedData->shadowDataEquivalent(*other.rareInheritedData.get()))
543            return true;
544
545        if (!rareInheritedData->quotesDataEquivalent(*other.rareInheritedData.get()))
546            return true;
547    }
548
549    if (inherited->textAutosizingMultiplier != other.inherited->textAutosizingMultiplier)
550        return true;
551
552    if (inherited.get() != other.inherited.get()) {
553        if (inherited->line_height != other.inherited->line_height
554            || inherited->font != other.inherited->font
555            || inherited->horizontal_border_spacing != other.inherited->horizontal_border_spacing
556            || inherited->vertical_border_spacing != other.inherited->vertical_border_spacing)
557            return true;
558    }
559
560    if (inherited_flags._box_direction != other.inherited_flags._box_direction
561        || inherited_flags.m_rtlOrdering != other.inherited_flags.m_rtlOrdering
562        || inherited_flags._text_align != other.inherited_flags._text_align
563        || inherited_flags._text_transform != other.inherited_flags._text_transform
564        || inherited_flags._direction != other.inherited_flags._direction
565        || inherited_flags._white_space != other.inherited_flags._white_space
566        || inherited_flags.m_writingMode != other.inherited_flags.m_writingMode)
567        return true;
568
569    if (noninherited_flags._overflowX != other.noninherited_flags._overflowX
570        || noninherited_flags._overflowY != other.noninherited_flags._overflowY
571        || noninherited_flags._clear != other.noninherited_flags._clear
572        || noninherited_flags._unicodeBidi != other.noninherited_flags._unicodeBidi
573        || noninherited_flags._position != other.noninherited_flags._position
574        || noninherited_flags._floating != other.noninherited_flags._floating
575        || noninherited_flags._originalDisplay != other.noninherited_flags._originalDisplay
576        || noninherited_flags._vertical_align != other.noninherited_flags._vertical_align)
577        return true;
578
579    if (noninherited_flags._effectiveDisplay >= FIRST_TABLE_DISPLAY && noninherited_flags._effectiveDisplay <= LAST_TABLE_DISPLAY) {
580        if (inherited_flags._border_collapse != other.inherited_flags._border_collapse
581            || inherited_flags._empty_cells != other.inherited_flags._empty_cells
582            || inherited_flags._caption_side != other.inherited_flags._caption_side
583            || noninherited_flags._table_layout != other.noninherited_flags._table_layout)
584            return true;
585
586        // In the collapsing border model, 'hidden' suppresses other borders, while 'none'
587        // does not, so these style differences can be width differences.
588        if (inherited_flags._border_collapse
589            && ((borderTopStyle() == BHIDDEN && other.borderTopStyle() == BNONE)
590                || (borderTopStyle() == BNONE && other.borderTopStyle() == BHIDDEN)
591                || (borderBottomStyle() == BHIDDEN && other.borderBottomStyle() == BNONE)
592                || (borderBottomStyle() == BNONE && other.borderBottomStyle() == BHIDDEN)
593                || (borderLeftStyle() == BHIDDEN && other.borderLeftStyle() == BNONE)
594                || (borderLeftStyle() == BNONE && other.borderLeftStyle() == BHIDDEN)
595                || (borderRightStyle() == BHIDDEN && other.borderRightStyle() == BNONE)
596                || (borderRightStyle() == BNONE && other.borderRightStyle() == BHIDDEN)))
597            return true;
598    } else if (noninherited_flags._effectiveDisplay == LIST_ITEM) {
599        if (inherited_flags._list_style_type != other.inherited_flags._list_style_type
600            || inherited_flags._list_style_position != other.inherited_flags._list_style_position)
601            return true;
602    }
603
604    if ((visibility() == COLLAPSE) != (other.visibility() == COLLAPSE))
605        return true;
606
607    if (!m_background->outline().visuallyEqual(other.m_background->outline())) {
608        // FIXME: We only really need to recompute the overflow but we don't have an optimized layout for it.
609        return true;
610    }
611
612    // Movement of non-static-positioned object is special cased in RenderStyle::visualInvalidationDiff().
613
614    return false;
615}
616
617bool RenderStyle::diffNeedsFullLayout(const RenderStyle& other) const
618{
619    return false;
620}
621
622bool RenderStyle::diffNeedsRepaintLayer(const RenderStyle& other) const
623{
624    if (position() != StaticPosition && (visual->clip != other.visual->clip || visual->hasClip != other.visual->hasClip))
625        return true;
626
627    if (rareNonInheritedData.get() != other.rareNonInheritedData.get()) {
628        if (RuntimeEnabledFeatures::cssCompositingEnabled()
629            && (rareNonInheritedData->m_effectiveBlendMode != other.rareNonInheritedData->m_effectiveBlendMode
630                || rareNonInheritedData->m_isolation != other.rareNonInheritedData->m_isolation))
631            return true;
632
633        if (rareNonInheritedData->m_mask != other.rareNonInheritedData->m_mask
634            || rareNonInheritedData->m_maskBoxImage != other.rareNonInheritedData->m_maskBoxImage)
635            return true;
636    }
637
638    return false;
639}
640
641bool RenderStyle::diffNeedsRepaintObject(const RenderStyle& other) const
642{
643    if (inherited_flags._visibility != other.inherited_flags._visibility
644        || inherited_flags.m_printColorAdjust != other.inherited_flags.m_printColorAdjust
645        || inherited_flags._insideLink != other.inherited_flags._insideLink
646        || !surround->border.visuallyEqual(other.surround->border)
647        || !m_background->visuallyEqual(*other.m_background))
648        return true;
649
650    if (rareInheritedData.get() != other.rareInheritedData.get()) {
651        if (rareInheritedData->userModify != other.rareInheritedData->userModify
652            || rareInheritedData->userSelect != other.rareInheritedData->userSelect
653            || rareInheritedData->m_imageRendering != other.rareInheritedData->m_imageRendering)
654            return true;
655    }
656
657    if (rareNonInheritedData.get() != other.rareNonInheritedData.get()) {
658        if (rareNonInheritedData->userDrag != other.rareNonInheritedData->userDrag
659            || rareNonInheritedData->m_borderFit != other.rareNonInheritedData->m_borderFit
660            || rareNonInheritedData->m_objectFit != other.rareNonInheritedData->m_objectFit
661            || rareNonInheritedData->m_objectPosition != other.rareNonInheritedData->m_objectPosition
662            || rareNonInheritedData->m_shapeOutside != other.rareNonInheritedData->m_shapeOutside
663            || rareNonInheritedData->m_clipPath != other.rareNonInheritedData->m_clipPath)
664            return true;
665    }
666
667    return false;
668}
669
670bool RenderStyle::diffNeedsRecompositeLayer(const RenderStyle& other) const
671{
672    if (rareNonInheritedData.get() != other.rareNonInheritedData.get()) {
673        if (rareNonInheritedData->m_transformStyle3D != other.rareNonInheritedData->m_transformStyle3D
674            || rareNonInheritedData->m_backfaceVisibility != other.rareNonInheritedData->m_backfaceVisibility
675            || rareNonInheritedData->m_perspective != other.rareNonInheritedData->m_perspective
676            || rareNonInheritedData->m_perspectiveOriginX != other.rareNonInheritedData->m_perspectiveOriginX
677            || rareNonInheritedData->m_perspectiveOriginY != other.rareNonInheritedData->m_perspectiveOriginY
678            || hasWillChangeCompositingHint() != other.hasWillChangeCompositingHint())
679            return true;
680    }
681
682    return false;
683}
684
685unsigned RenderStyle::computeChangedContextSensitiveProperties(const RenderStyle& other, StyleDifference diff) const
686{
687    unsigned changedContextSensitiveProperties = ContextSensitivePropertyNone;
688
689    // StyleAdjuster has ensured that zIndex is non-auto only if it's applicable.
690    if (m_box->zIndex() != other.m_box->zIndex() || m_box->hasAutoZIndex() != other.m_box->hasAutoZIndex())
691        changedContextSensitiveProperties |= ContextSensitivePropertyZIndex;
692
693    if (rareNonInheritedData.get() != other.rareNonInheritedData.get()) {
694        if (!transformDataEquivalent(other))
695            changedContextSensitiveProperties |= ContextSensitivePropertyTransform;
696
697        if (rareNonInheritedData->opacity != other.rareNonInheritedData->opacity)
698            changedContextSensitiveProperties |= ContextSensitivePropertyOpacity;
699
700        if (rareNonInheritedData->m_filter != other.rareNonInheritedData->m_filter)
701            changedContextSensitiveProperties |= ContextSensitivePropertyFilter;
702    }
703
704    if (!diff.needsRepaint()) {
705        if (inherited->color != other.inherited->color
706            || inherited_flags.m_textUnderline != other.inherited_flags.m_textUnderline
707            || visual->textDecoration != other.visual->textDecoration) {
708            changedContextSensitiveProperties |= ContextSensitivePropertyTextOrColor;
709        } else if (rareNonInheritedData.get() != other.rareNonInheritedData.get()) {
710            if (rareNonInheritedData->m_textDecorationStyle != other.rareNonInheritedData->m_textDecorationStyle
711                || rareNonInheritedData->m_textDecorationColor != other.rareNonInheritedData->m_textDecorationColor)
712                changedContextSensitiveProperties |= ContextSensitivePropertyTextOrColor;
713        } else if (rareInheritedData.get() != other.rareInheritedData.get()) {
714            if (rareInheritedData->textFillColor() != other.rareInheritedData->textFillColor()
715                || rareInheritedData->textStrokeColor() != other.rareInheritedData->textStrokeColor()
716                || rareInheritedData->textEmphasisColor() != other.rareInheritedData->textEmphasisColor()
717                || rareInheritedData->textEmphasisFill != other.rareInheritedData->textEmphasisFill
718                || rareInheritedData->appliedTextDecorations != other.rareInheritedData->appliedTextDecorations)
719                changedContextSensitiveProperties |= ContextSensitivePropertyTextOrColor;
720        }
721    }
722
723    return changedContextSensitiveProperties;
724}
725
726void RenderStyle::setClip(const Length& top, const Length& right, const Length& bottom, const Length& left)
727{
728    StyleVisualData* data = visual.access();
729    data->clip.m_top = top;
730    data->clip.m_right = right;
731    data->clip.m_bottom = bottom;
732    data->clip.m_left = left;
733}
734
735void RenderStyle::addCursor(PassRefPtr<StyleImage> image, const IntPoint& hotSpot)
736{
737    if (!rareInheritedData.access()->cursorData)
738        rareInheritedData.access()->cursorData = CursorList::create();
739    rareInheritedData.access()->cursorData->append(CursorData(image, hotSpot));
740}
741
742void RenderStyle::setCursorList(PassRefPtr<CursorList> other)
743{
744    rareInheritedData.access()->cursorData = other;
745}
746
747void RenderStyle::setQuotes(PassRefPtr<QuotesData> q)
748{
749    rareInheritedData.access()->quotes = q;
750}
751
752void RenderStyle::clearCursorList()
753{
754    if (rareInheritedData->cursorData)
755        rareInheritedData.access()->cursorData = nullptr;
756}
757
758void RenderStyle::addCallbackSelector(const String& selector)
759{
760    if (!rareNonInheritedData->m_callbackSelectors.contains(selector))
761        rareNonInheritedData.access()->m_callbackSelectors.append(selector);
762}
763
764void RenderStyle::clearContent()
765{
766    if (rareNonInheritedData->m_content)
767        rareNonInheritedData.access()->m_content = nullptr;
768}
769
770void RenderStyle::appendContent(PassOwnPtr<ContentData> contentData)
771{
772    OwnPtr<ContentData>& content = rareNonInheritedData.access()->m_content;
773    ContentData* lastContent = content.get();
774    while (lastContent && lastContent->next())
775        lastContent = lastContent->next();
776
777    if (lastContent)
778        lastContent->setNext(contentData);
779    else
780        content = contentData;
781}
782
783void RenderStyle::setContent(PassRefPtr<StyleImage> image, bool add)
784{
785    if (!image)
786        return;
787
788    if (add) {
789        appendContent(ContentData::create(image));
790        return;
791    }
792
793    rareNonInheritedData.access()->m_content = ContentData::create(image);
794}
795
796void RenderStyle::setContent(const String& string, bool add)
797{
798    OwnPtr<ContentData>& content = rareNonInheritedData.access()->m_content;
799    if (add) {
800        ContentData* lastContent = content.get();
801        while (lastContent && lastContent->next())
802            lastContent = lastContent->next();
803
804        if (lastContent) {
805            // We attempt to merge with the last ContentData if possible.
806            if (lastContent->isText()) {
807                TextContentData* textContent = static_cast<TextContentData*>(lastContent);
808                textContent->setText(textContent->text() + string);
809            } else
810                lastContent->setNext(ContentData::create(string));
811
812            return;
813        }
814    }
815
816    content = ContentData::create(string);
817}
818
819void RenderStyle::setContent(PassOwnPtr<CounterContent> counter, bool add)
820{
821    if (!counter)
822        return;
823
824    if (add) {
825        appendContent(ContentData::create(counter));
826        return;
827    }
828
829    rareNonInheritedData.access()->m_content = ContentData::create(counter);
830}
831
832void RenderStyle::setContent(QuoteType quote, bool add)
833{
834    if (add) {
835        appendContent(ContentData::create(quote));
836        return;
837    }
838
839    rareNonInheritedData.access()->m_content = ContentData::create(quote);
840}
841
842blink::WebBlendMode RenderStyle::blendMode() const
843{
844    if (RuntimeEnabledFeatures::cssCompositingEnabled())
845        return static_cast<blink::WebBlendMode>(rareNonInheritedData->m_effectiveBlendMode);
846    return blink::WebBlendModeNormal;
847}
848
849void RenderStyle::setBlendMode(blink::WebBlendMode v)
850{
851    if (RuntimeEnabledFeatures::cssCompositingEnabled())
852        rareNonInheritedData.access()->m_effectiveBlendMode = v;
853}
854
855bool RenderStyle::hasBlendMode() const
856{
857    if (RuntimeEnabledFeatures::cssCompositingEnabled())
858        return static_cast<blink::WebBlendMode>(rareNonInheritedData->m_effectiveBlendMode) != blink::WebBlendModeNormal;
859    return false;
860}
861
862EIsolation RenderStyle::isolation() const
863{
864    if (RuntimeEnabledFeatures::cssCompositingEnabled())
865        return static_cast<EIsolation>(rareNonInheritedData->m_isolation);
866    return IsolationAuto;
867}
868
869void RenderStyle::setIsolation(EIsolation v)
870{
871    if (RuntimeEnabledFeatures::cssCompositingEnabled())
872        rareNonInheritedData.access()->m_isolation = v;
873}
874
875bool RenderStyle::hasIsolation() const
876{
877    if (RuntimeEnabledFeatures::cssCompositingEnabled())
878        return rareNonInheritedData->m_isolation != IsolationAuto;
879    return false;
880}
881
882bool RenderStyle::hasWillChangeCompositingHint() const
883{
884    for (size_t i = 0; i < rareNonInheritedData->m_willChange->m_properties.size(); ++i) {
885        switch (rareNonInheritedData->m_willChange->m_properties[i]) {
886        case CSSPropertyOpacity:
887        case CSSPropertyTransform:
888        case CSSPropertyWebkitTransform:
889        case CSSPropertyTop:
890        case CSSPropertyLeft:
891        case CSSPropertyBottom:
892        case CSSPropertyRight:
893            return true;
894        default:
895            break;
896        }
897    }
898    return false;
899}
900
901inline bool requireTransformOrigin(const Vector<RefPtr<TransformOperation> >& transformOperations, RenderStyle::ApplyTransformOrigin applyOrigin)
902{
903    // transform-origin brackets the transform with translate operations.
904    // Optimize for the case where the only transform is a translation, since the transform-origin is irrelevant
905    // in that case.
906    if (applyOrigin != RenderStyle::IncludeTransformOrigin)
907        return false;
908
909    unsigned size = transformOperations.size();
910    for (unsigned i = 0; i < size; ++i) {
911        TransformOperation::OperationType type = transformOperations[i]->type();
912        if (type != TransformOperation::TranslateX
913            && type != TransformOperation::TranslateY
914            && type != TransformOperation::Translate
915            && type != TransformOperation::TranslateZ
916            && type != TransformOperation::Translate3D)
917            return true;
918    }
919
920    return false;
921}
922
923void RenderStyle::applyTransform(TransformationMatrix& transform, const LayoutSize& borderBoxSize, ApplyTransformOrigin applyOrigin) const
924{
925    applyTransform(transform, FloatRect(FloatPoint(), borderBoxSize), applyOrigin);
926}
927
928void RenderStyle::applyTransform(TransformationMatrix& transform, const FloatRect& boundingBox, ApplyTransformOrigin applyOrigin) const
929{
930    const Vector<RefPtr<TransformOperation> >& transformOperations = rareNonInheritedData->m_transform->m_operations.operations();
931    bool applyTransformOrigin = requireTransformOrigin(transformOperations, applyOrigin);
932
933    float offsetX = transformOriginX().type() == Percent ? boundingBox.x() : 0;
934    float offsetY = transformOriginY().type() == Percent ? boundingBox.y() : 0;
935
936    if (applyTransformOrigin) {
937        transform.translate3d(floatValueForLength(transformOriginX(), boundingBox.width()) + offsetX,
938            floatValueForLength(transformOriginY(), boundingBox.height()) + offsetY,
939            transformOriginZ());
940    }
941
942    unsigned size = transformOperations.size();
943    for (unsigned i = 0; i < size; ++i)
944        transformOperations[i]->apply(transform, boundingBox.size());
945
946    if (applyTransformOrigin) {
947        transform.translate3d(-floatValueForLength(transformOriginX(), boundingBox.width()) - offsetX,
948            -floatValueForLength(transformOriginY(), boundingBox.height()) - offsetY,
949            -transformOriginZ());
950    }
951}
952
953void RenderStyle::setTextShadow(PassRefPtr<ShadowList> s)
954{
955    rareInheritedData.access()->textShadow = s;
956}
957
958void RenderStyle::setBoxShadow(PassRefPtr<ShadowList> s)
959{
960    rareNonInheritedData.access()->m_boxShadow = s;
961}
962
963static RoundedRect::Radii calcRadiiFor(const BorderData& border, IntSize size)
964{
965    return RoundedRect::Radii(
966        IntSize(valueForLength(border.topLeft().width(), size.width()),
967            valueForLength(border.topLeft().height(), size.height())),
968        IntSize(valueForLength(border.topRight().width(), size.width()),
969            valueForLength(border.topRight().height(), size.height())),
970        IntSize(valueForLength(border.bottomLeft().width(), size.width()),
971            valueForLength(border.bottomLeft().height(), size.height())),
972        IntSize(valueForLength(border.bottomRight().width(), size.width()),
973            valueForLength(border.bottomRight().height(), size.height())));
974}
975
976StyleImage* RenderStyle::listStyleImage() const { return rareInheritedData->listStyleImage.get(); }
977void RenderStyle::setListStyleImage(PassRefPtr<StyleImage> v)
978{
979    if (rareInheritedData->listStyleImage != v)
980        rareInheritedData.access()->listStyleImage = v;
981}
982
983Color RenderStyle::color() const { return inherited->color; }
984Color RenderStyle::visitedLinkColor() const { return inherited->visitedLinkColor; }
985void RenderStyle::setColor(const Color& v) { SET_VAR(inherited, color, v); }
986void RenderStyle::setVisitedLinkColor(const Color& v) { SET_VAR(inherited, visitedLinkColor, v); }
987
988short RenderStyle::horizontalBorderSpacing() const { return inherited->horizontal_border_spacing; }
989short RenderStyle::verticalBorderSpacing() const { return inherited->vertical_border_spacing; }
990void RenderStyle::setHorizontalBorderSpacing(short v) { SET_VAR(inherited, horizontal_border_spacing, v); }
991void RenderStyle::setVerticalBorderSpacing(short v) { SET_VAR(inherited, vertical_border_spacing, v); }
992
993RoundedRect RenderStyle::getRoundedBorderFor(const LayoutRect& borderRect, bool includeLogicalLeftEdge, bool includeLogicalRightEdge) const
994{
995    IntRect snappedBorderRect(pixelSnappedIntRect(borderRect));
996    RoundedRect roundedRect(snappedBorderRect);
997    if (hasBorderRadius()) {
998        RoundedRect::Radii radii = calcRadiiFor(surround->border, snappedBorderRect.size());
999        radii.scale(calcBorderRadiiConstraintScaleFor(borderRect, radii));
1000        roundedRect.includeLogicalEdges(radii, isHorizontalWritingMode(), includeLogicalLeftEdge, includeLogicalRightEdge);
1001    }
1002    return roundedRect;
1003}
1004
1005RoundedRect RenderStyle::getRoundedInnerBorderFor(const LayoutRect& borderRect, bool includeLogicalLeftEdge, bool includeLogicalRightEdge) const
1006{
1007    bool horizontal = isHorizontalWritingMode();
1008
1009    int leftWidth = (!horizontal || includeLogicalLeftEdge) ? borderLeftWidth() : 0;
1010    int rightWidth = (!horizontal || includeLogicalRightEdge) ? borderRightWidth() : 0;
1011    int topWidth = (horizontal || includeLogicalLeftEdge) ? borderTopWidth() : 0;
1012    int bottomWidth = (horizontal || includeLogicalRightEdge) ? borderBottomWidth() : 0;
1013
1014    return getRoundedInnerBorderFor(borderRect, topWidth, bottomWidth, leftWidth, rightWidth, includeLogicalLeftEdge, includeLogicalRightEdge);
1015}
1016
1017RoundedRect RenderStyle::getRoundedInnerBorderFor(const LayoutRect& borderRect,
1018    int topWidth, int bottomWidth, int leftWidth, int rightWidth, bool includeLogicalLeftEdge, bool includeLogicalRightEdge) const
1019{
1020    LayoutRect innerRect(borderRect.x() + leftWidth,
1021               borderRect.y() + topWidth,
1022               borderRect.width() - leftWidth - rightWidth,
1023               borderRect.height() - topWidth - bottomWidth);
1024
1025    RoundedRect roundedRect(pixelSnappedIntRect(innerRect));
1026
1027    if (hasBorderRadius()) {
1028        RoundedRect::Radii radii = getRoundedBorderFor(borderRect).radii();
1029        radii.shrink(topWidth, bottomWidth, leftWidth, rightWidth);
1030        roundedRect.includeLogicalEdges(radii, isHorizontalWritingMode(), includeLogicalLeftEdge, includeLogicalRightEdge);
1031    }
1032    return roundedRect;
1033}
1034
1035static bool allLayersAreFixed(const FillLayer* layer)
1036{
1037    bool allFixed = true;
1038
1039    for (const FillLayer* currLayer = layer; currLayer; currLayer = currLayer->next())
1040        allFixed &= (currLayer->image() && currLayer->attachment() == FixedBackgroundAttachment);
1041
1042    return layer && allFixed;
1043}
1044
1045bool RenderStyle::hasEntirelyFixedBackground() const
1046{
1047    return allLayersAreFixed(backgroundLayers());
1048}
1049
1050const CounterDirectiveMap* RenderStyle::counterDirectives() const
1051{
1052    return rareNonInheritedData->m_counterDirectives.get();
1053}
1054
1055CounterDirectiveMap& RenderStyle::accessCounterDirectives()
1056{
1057    OwnPtr<CounterDirectiveMap>& map = rareNonInheritedData.access()->m_counterDirectives;
1058    if (!map)
1059        map = adoptPtr(new CounterDirectiveMap);
1060    return *map;
1061}
1062
1063const CounterDirectives RenderStyle::getCounterDirectives(const AtomicString& identifier) const
1064{
1065    if (const CounterDirectiveMap* directives = counterDirectives())
1066        return directives->get(identifier);
1067    return CounterDirectives();
1068}
1069
1070const AtomicString& RenderStyle::hyphenString() const
1071{
1072    const AtomicString& hyphenationString = rareInheritedData.get()->hyphenationString;
1073    if (!hyphenationString.isNull())
1074        return hyphenationString;
1075
1076    // FIXME: This should depend on locale.
1077    DEFINE_STATIC_LOCAL(AtomicString, hyphenMinusString, (&hyphenMinus, 1));
1078    DEFINE_STATIC_LOCAL(AtomicString, hyphenString, (&hyphen, 1));
1079    return font().primaryFontHasGlyphForCharacter(hyphen) ? hyphenString : hyphenMinusString;
1080}
1081
1082const AtomicString& RenderStyle::textEmphasisMarkString() const
1083{
1084    switch (textEmphasisMark()) {
1085    case TextEmphasisMarkNone:
1086        return nullAtom;
1087    case TextEmphasisMarkCustom:
1088        return textEmphasisCustomMark();
1089    case TextEmphasisMarkDot: {
1090        DEFINE_STATIC_LOCAL(AtomicString, filledDotString, (&bullet, 1));
1091        DEFINE_STATIC_LOCAL(AtomicString, openDotString, (&whiteBullet, 1));
1092        return textEmphasisFill() == TextEmphasisFillFilled ? filledDotString : openDotString;
1093    }
1094    case TextEmphasisMarkCircle: {
1095        DEFINE_STATIC_LOCAL(AtomicString, filledCircleString, (&blackCircle, 1));
1096        DEFINE_STATIC_LOCAL(AtomicString, openCircleString, (&whiteCircle, 1));
1097        return textEmphasisFill() == TextEmphasisFillFilled ? filledCircleString : openCircleString;
1098    }
1099    case TextEmphasisMarkDoubleCircle: {
1100        DEFINE_STATIC_LOCAL(AtomicString, filledDoubleCircleString, (&fisheye, 1));
1101        DEFINE_STATIC_LOCAL(AtomicString, openDoubleCircleString, (&bullseye, 1));
1102        return textEmphasisFill() == TextEmphasisFillFilled ? filledDoubleCircleString : openDoubleCircleString;
1103    }
1104    case TextEmphasisMarkTriangle: {
1105        DEFINE_STATIC_LOCAL(AtomicString, filledTriangleString, (&blackUpPointingTriangle, 1));
1106        DEFINE_STATIC_LOCAL(AtomicString, openTriangleString, (&whiteUpPointingTriangle, 1));
1107        return textEmphasisFill() == TextEmphasisFillFilled ? filledTriangleString : openTriangleString;
1108    }
1109    case TextEmphasisMarkSesame: {
1110        DEFINE_STATIC_LOCAL(AtomicString, filledSesameString, (&sesameDot, 1));
1111        DEFINE_STATIC_LOCAL(AtomicString, openSesameString, (&whiteSesameDot, 1));
1112        return textEmphasisFill() == TextEmphasisFillFilled ? filledSesameString : openSesameString;
1113    }
1114    case TextEmphasisMarkAuto:
1115        ASSERT_NOT_REACHED();
1116        return nullAtom;
1117    }
1118
1119    ASSERT_NOT_REACHED();
1120    return nullAtom;
1121}
1122
1123CSSAnimationData& RenderStyle::accessAnimations()
1124{
1125    if (!rareNonInheritedData.access()->m_animations)
1126        rareNonInheritedData.access()->m_animations = CSSAnimationData::create();
1127    return *rareNonInheritedData->m_animations;
1128}
1129
1130CSSTransitionData& RenderStyle::accessTransitions()
1131{
1132    if (!rareNonInheritedData.access()->m_transitions)
1133        rareNonInheritedData.access()->m_transitions = CSSTransitionData::create();
1134    return *rareNonInheritedData->m_transitions;
1135}
1136
1137const Font& RenderStyle::font() const { return inherited->font; }
1138const FontMetrics& RenderStyle::fontMetrics() const { return inherited->font.fontMetrics(); }
1139const FontDescription& RenderStyle::fontDescription() const { return inherited->font.fontDescription(); }
1140float RenderStyle::specifiedFontSize() const { return fontDescription().specifiedSize(); }
1141float RenderStyle::computedFontSize() const { return fontDescription().computedSize(); }
1142int RenderStyle::fontSize() const { return fontDescription().computedPixelSize(); }
1143FontWeight RenderStyle::fontWeight() const { return fontDescription().weight(); }
1144
1145TextDecoration RenderStyle::textDecorationsInEffect() const
1146{
1147    int decorations = 0;
1148
1149    const Vector<AppliedTextDecoration>& applied = appliedTextDecorations();
1150
1151    for (size_t i = 0; i < applied.size(); ++i)
1152        decorations |= applied[i].line();
1153
1154    return static_cast<TextDecoration>(decorations);
1155}
1156
1157const Vector<AppliedTextDecoration>& RenderStyle::appliedTextDecorations() const
1158{
1159    if (!inherited_flags.m_textUnderline && !rareInheritedData->appliedTextDecorations) {
1160        DEFINE_STATIC_LOCAL(Vector<AppliedTextDecoration>, empty, ());
1161        return empty;
1162    }
1163    if (inherited_flags.m_textUnderline) {
1164        DEFINE_STATIC_LOCAL(Vector<AppliedTextDecoration>, underline, (1, AppliedTextDecoration(TextDecorationUnderline)));
1165        return underline;
1166    }
1167
1168    return rareInheritedData->appliedTextDecorations->vector();
1169}
1170
1171float RenderStyle::wordSpacing() const { return fontDescription().wordSpacing(); }
1172float RenderStyle::letterSpacing() const { return fontDescription().letterSpacing(); }
1173
1174bool RenderStyle::setFontDescription(const FontDescription& v)
1175{
1176    if (inherited->font.fontDescription() != v) {
1177        inherited.access()->font = Font(v);
1178        return true;
1179    }
1180    return false;
1181}
1182
1183const Length& RenderStyle::specifiedLineHeight() const { return inherited->line_height; }
1184Length RenderStyle::lineHeight() const
1185{
1186    const Length& lh = inherited->line_height;
1187    // Unlike fontDescription().computedSize() and hence fontSize(), this is
1188    // recalculated on demand as we only store the specified line height.
1189    // FIXME: Should consider scaling the fixed part of any calc expressions
1190    // too, though this involves messily poking into CalcExpressionLength.
1191    float multiplier = textAutosizingMultiplier();
1192    if (multiplier > 1 && lh.isFixed())
1193        return Length(TextAutosizer::computeAutosizedFontSize(lh.value(), multiplier), Fixed);
1194
1195    return lh;
1196}
1197
1198void RenderStyle::setLineHeight(const Length& specifiedLineHeight) { SET_VAR(inherited, line_height, specifiedLineHeight); }
1199
1200int RenderStyle::computedLineHeight() const
1201{
1202    const Length& lh = lineHeight();
1203
1204    // Negative value means the line height is not set. Use the font's built-in spacing.
1205    if (lh.isNegative())
1206        return fontMetrics().lineSpacing();
1207
1208    if (lh.isPercent())
1209        return minimumValueForLength(lh, fontSize());
1210
1211    return lh.value();
1212}
1213
1214void RenderStyle::setWordSpacing(float wordSpacing)
1215{
1216    FontSelector* currentFontSelector = font().fontSelector();
1217    FontDescription desc(fontDescription());
1218    desc.setWordSpacing(wordSpacing);
1219    setFontDescription(desc);
1220    font().update(currentFontSelector);
1221}
1222
1223void RenderStyle::setLetterSpacing(float letterSpacing)
1224{
1225    FontSelector* currentFontSelector = font().fontSelector();
1226    FontDescription desc(fontDescription());
1227    desc.setLetterSpacing(letterSpacing);
1228    setFontDescription(desc);
1229    font().update(currentFontSelector);
1230}
1231
1232void RenderStyle::setFontSize(float size)
1233{
1234    // size must be specifiedSize if Text Autosizing is enabled, but computedSize if text
1235    // zoom is enabled (if neither is enabled it's irrelevant as they're probably the same).
1236
1237    ASSERT(std::isfinite(size));
1238    if (!std::isfinite(size) || size < 0)
1239        size = 0;
1240    else
1241        size = min(maximumAllowedFontSize, size);
1242
1243    FontSelector* currentFontSelector = font().fontSelector();
1244    FontDescription desc(fontDescription());
1245    desc.setSpecifiedSize(size);
1246    desc.setComputedSize(size);
1247
1248    float multiplier = textAutosizingMultiplier();
1249    if (multiplier > 1) {
1250        float autosizedFontSize = TextAutosizer::computeAutosizedFontSize(size, multiplier);
1251        desc.setComputedSize(min(maximumAllowedFontSize, autosizedFontSize));
1252    }
1253
1254    setFontDescription(desc);
1255    font().update(currentFontSelector);
1256}
1257
1258void RenderStyle::setFontWeight(FontWeight weight)
1259{
1260    FontSelector* currentFontSelector = font().fontSelector();
1261    FontDescription desc(fontDescription());
1262    desc.setWeight(weight);
1263    setFontDescription(desc);
1264    font().update(currentFontSelector);
1265}
1266
1267void RenderStyle::addAppliedTextDecoration(const AppliedTextDecoration& decoration)
1268{
1269    RefPtr<AppliedTextDecorationList>& list = rareInheritedData.access()->appliedTextDecorations;
1270
1271    if (!list)
1272        list = AppliedTextDecorationList::create();
1273    else if (!list->hasOneRef())
1274        list = list->copy();
1275
1276    if (inherited_flags.m_textUnderline) {
1277        inherited_flags.m_textUnderline = false;
1278        list->append(AppliedTextDecoration(TextDecorationUnderline));
1279    }
1280
1281    list->append(decoration);
1282}
1283
1284void RenderStyle::applyTextDecorations()
1285{
1286    if (textDecoration() == TextDecorationNone)
1287        return;
1288
1289    TextDecorationStyle style = textDecorationStyle();
1290    StyleColor styleColor = visitedDependentDecorationStyleColor();
1291
1292    int decorations = textDecoration();
1293
1294    if (decorations & TextDecorationUnderline) {
1295        // To save memory, we don't use AppliedTextDecoration objects in the
1296        // common case of a single simple underline.
1297        AppliedTextDecoration underline(TextDecorationUnderline, style, styleColor);
1298
1299        if (!rareInheritedData->appliedTextDecorations && underline.isSimpleUnderline())
1300            inherited_flags.m_textUnderline = true;
1301        else
1302            addAppliedTextDecoration(underline);
1303    }
1304    if (decorations & TextDecorationOverline)
1305        addAppliedTextDecoration(AppliedTextDecoration(TextDecorationOverline, style, styleColor));
1306    if (decorations & TextDecorationLineThrough)
1307        addAppliedTextDecoration(AppliedTextDecoration(TextDecorationLineThrough, style, styleColor));
1308}
1309
1310void RenderStyle::clearAppliedTextDecorations()
1311{
1312    inherited_flags.m_textUnderline = false;
1313
1314    if (rareInheritedData->appliedTextDecorations)
1315        rareInheritedData.access()->appliedTextDecorations = nullptr;
1316}
1317
1318void RenderStyle::getShadowExtent(const ShadowList* shadowList, LayoutUnit &top, LayoutUnit &right, LayoutUnit &bottom, LayoutUnit &left) const
1319{
1320    top = 0;
1321    right = 0;
1322    bottom = 0;
1323    left = 0;
1324
1325    size_t shadowCount = shadowList ? shadowList->shadows().size() : 0;
1326    for (size_t i = 0; i < shadowCount; ++i) {
1327        const ShadowData& shadow = shadowList->shadows()[i];
1328        if (shadow.style() == Inset)
1329            continue;
1330        float blurAndSpread = shadow.blur() + shadow.spread();
1331
1332        top = min<LayoutUnit>(top, shadow.y() - blurAndSpread);
1333        right = max<LayoutUnit>(right, shadow.x() + blurAndSpread);
1334        bottom = max<LayoutUnit>(bottom, shadow.y() + blurAndSpread);
1335        left = min<LayoutUnit>(left, shadow.x() - blurAndSpread);
1336    }
1337}
1338
1339LayoutBoxExtent RenderStyle::getShadowInsetExtent(const ShadowList* shadowList) const
1340{
1341    LayoutUnit top = 0;
1342    LayoutUnit right = 0;
1343    LayoutUnit bottom = 0;
1344    LayoutUnit left = 0;
1345
1346    size_t shadowCount = shadowList ? shadowList->shadows().size() : 0;
1347    for (size_t i = 0; i < shadowCount; ++i) {
1348        const ShadowData& shadow = shadowList->shadows()[i];
1349        if (shadow.style() == Normal)
1350            continue;
1351        float blurAndSpread = shadow.blur() + shadow.spread();
1352        top = max<LayoutUnit>(top, shadow.y() + blurAndSpread);
1353        right = min<LayoutUnit>(right, shadow.x() - blurAndSpread);
1354        bottom = min<LayoutUnit>(bottom, shadow.y() - blurAndSpread);
1355        left = max<LayoutUnit>(left, shadow.x() + blurAndSpread);
1356    }
1357
1358    return LayoutBoxExtent(top, right, bottom, left);
1359}
1360
1361void RenderStyle::getShadowHorizontalExtent(const ShadowList* shadowList, LayoutUnit &left, LayoutUnit &right) const
1362{
1363    left = 0;
1364    right = 0;
1365
1366    size_t shadowCount = shadowList ? shadowList->shadows().size() : 0;
1367    for (size_t i = 0; i < shadowCount; ++i) {
1368        const ShadowData& shadow = shadowList->shadows()[i];
1369        if (shadow.style() == Inset)
1370            continue;
1371        float blurAndSpread = shadow.blur() + shadow.spread();
1372
1373        left = min<LayoutUnit>(left, shadow.x() - blurAndSpread);
1374        right = max<LayoutUnit>(right, shadow.x() + blurAndSpread);
1375    }
1376}
1377
1378void RenderStyle::getShadowVerticalExtent(const ShadowList* shadowList, LayoutUnit &top, LayoutUnit &bottom) const
1379{
1380    top = 0;
1381    bottom = 0;
1382
1383    size_t shadowCount = shadowList ? shadowList->shadows().size() : 0;
1384    for (size_t i = 0; i < shadowCount; ++i) {
1385        const ShadowData& shadow = shadowList->shadows()[i];
1386        if (shadow.style() == Inset)
1387            continue;
1388        float blurAndSpread = shadow.blur() + shadow.spread();
1389
1390        top = min<LayoutUnit>(top, shadow.y() - blurAndSpread);
1391        bottom = max<LayoutUnit>(bottom, shadow.y() + blurAndSpread);
1392    }
1393}
1394
1395StyleColor RenderStyle::visitedDependentDecorationStyleColor() const
1396{
1397    bool isVisited = insideLink() == InsideVisitedLink;
1398
1399    StyleColor styleColor = isVisited ? visitedLinkTextDecorationColor() : textDecorationColor();
1400
1401    if (!styleColor.isCurrentColor())
1402        return styleColor;
1403
1404    if (textStrokeWidth()) {
1405        // Prefer stroke color if possible, but not if it's fully transparent.
1406        StyleColor textStrokeStyleColor = isVisited ? visitedLinkTextStrokeColor() : textStrokeColor();
1407        if (!textStrokeStyleColor.isCurrentColor() && textStrokeStyleColor.color().alpha())
1408            return textStrokeStyleColor;
1409    }
1410
1411    return isVisited ? visitedLinkTextFillColor() : textFillColor();
1412}
1413
1414Color RenderStyle::visitedDependentDecorationColor() const
1415{
1416    bool isVisited = insideLink() == InsideVisitedLink;
1417    return visitedDependentDecorationStyleColor().resolve(isVisited ? visitedLinkColor() : color());
1418}
1419
1420Color RenderStyle::colorIncludingFallback(int colorProperty, bool visitedLink) const
1421{
1422    StyleColor result(StyleColor::currentColor());
1423    EBorderStyle borderStyle = BNONE;
1424    switch (colorProperty) {
1425    case CSSPropertyBackgroundColor:
1426        result = visitedLink ? visitedLinkBackgroundColor() : backgroundColor();
1427        break;
1428    case CSSPropertyBorderLeftColor:
1429        result = visitedLink ? visitedLinkBorderLeftColor() : borderLeftColor();
1430        borderStyle = borderLeftStyle();
1431        break;
1432    case CSSPropertyBorderRightColor:
1433        result = visitedLink ? visitedLinkBorderRightColor() : borderRightColor();
1434        borderStyle = borderRightStyle();
1435        break;
1436    case CSSPropertyBorderTopColor:
1437        result = visitedLink ? visitedLinkBorderTopColor() : borderTopColor();
1438        borderStyle = borderTopStyle();
1439        break;
1440    case CSSPropertyBorderBottomColor:
1441        result = visitedLink ? visitedLinkBorderBottomColor() : borderBottomColor();
1442        borderStyle = borderBottomStyle();
1443        break;
1444    case CSSPropertyColor:
1445        result = visitedLink ? visitedLinkColor() : color();
1446        break;
1447    case CSSPropertyOutlineColor:
1448        result = visitedLink ? visitedLinkOutlineColor() : outlineColor();
1449        break;
1450    case CSSPropertyWebkitColumnRuleColor:
1451        result = visitedLink ? visitedLinkColumnRuleColor() : columnRuleColor();
1452        break;
1453    case CSSPropertyWebkitTextEmphasisColor:
1454        result = visitedLink ? visitedLinkTextEmphasisColor() : textEmphasisColor();
1455        break;
1456    case CSSPropertyWebkitTextFillColor:
1457        result = visitedLink ? visitedLinkTextFillColor() : textFillColor();
1458        break;
1459    case CSSPropertyWebkitTextStrokeColor:
1460        result = visitedLink ? visitedLinkTextStrokeColor() : textStrokeColor();
1461        break;
1462    case CSSPropertyFloodColor:
1463        result = floodColor();
1464        break;
1465    case CSSPropertyLightingColor:
1466        result = lightingColor();
1467        break;
1468    case CSSPropertyStopColor:
1469        result = stopColor();
1470        break;
1471    case CSSPropertyWebkitTapHighlightColor:
1472        result = tapHighlightColor();
1473        break;
1474    default:
1475        ASSERT_NOT_REACHED();
1476        break;
1477    }
1478
1479    if (!result.isCurrentColor())
1480        return result.color();
1481
1482    // FIXME: Treating styled borders with initial color differently causes problems
1483    // See crbug.com/316559, crbug.com/276231
1484    if (!visitedLink && (borderStyle == INSET || borderStyle == OUTSET || borderStyle == RIDGE || borderStyle == GROOVE))
1485        return Color(238, 238, 238);
1486    return visitedLink ? visitedLinkColor() : color();
1487}
1488
1489Color RenderStyle::visitedDependentColor(int colorProperty) const
1490{
1491    Color unvisitedColor = colorIncludingFallback(colorProperty, false);
1492    if (insideLink() != InsideVisitedLink)
1493        return unvisitedColor;
1494
1495    Color visitedColor = colorIncludingFallback(colorProperty, true);
1496
1497    // FIXME: Technically someone could explicitly specify the color transparent, but for now we'll just
1498    // assume that if the background color is transparent that it wasn't set. Note that it's weird that
1499    // we're returning unvisited info for a visited link, but given our restriction that the alpha values
1500    // have to match, it makes more sense to return the unvisited background color if specified than it
1501    // does to return black. This behavior matches what Firefox 4 does as well.
1502    if (colorProperty == CSSPropertyBackgroundColor && visitedColor == Color::transparent)
1503        return unvisitedColor;
1504
1505    // Take the alpha from the unvisited color, but get the RGB values from the visited color.
1506    return Color(visitedColor.red(), visitedColor.green(), visitedColor.blue(), unvisitedColor.alpha());
1507}
1508
1509const BorderValue& RenderStyle::borderBefore() const
1510{
1511    switch (writingMode()) {
1512    case TopToBottomWritingMode:
1513        return borderTop();
1514    case BottomToTopWritingMode:
1515        return borderBottom();
1516    case LeftToRightWritingMode:
1517        return borderLeft();
1518    case RightToLeftWritingMode:
1519        return borderRight();
1520    }
1521    ASSERT_NOT_REACHED();
1522    return borderTop();
1523}
1524
1525const BorderValue& RenderStyle::borderAfter() const
1526{
1527    switch (writingMode()) {
1528    case TopToBottomWritingMode:
1529        return borderBottom();
1530    case BottomToTopWritingMode:
1531        return borderTop();
1532    case LeftToRightWritingMode:
1533        return borderRight();
1534    case RightToLeftWritingMode:
1535        return borderLeft();
1536    }
1537    ASSERT_NOT_REACHED();
1538    return borderBottom();
1539}
1540
1541const BorderValue& RenderStyle::borderStart() const
1542{
1543    if (isHorizontalWritingMode())
1544        return isLeftToRightDirection() ? borderLeft() : borderRight();
1545    return isLeftToRightDirection() ? borderTop() : borderBottom();
1546}
1547
1548const BorderValue& RenderStyle::borderEnd() const
1549{
1550    if (isHorizontalWritingMode())
1551        return isLeftToRightDirection() ? borderRight() : borderLeft();
1552    return isLeftToRightDirection() ? borderBottom() : borderTop();
1553}
1554
1555unsigned short RenderStyle::borderBeforeWidth() const
1556{
1557    switch (writingMode()) {
1558    case TopToBottomWritingMode:
1559        return borderTopWidth();
1560    case BottomToTopWritingMode:
1561        return borderBottomWidth();
1562    case LeftToRightWritingMode:
1563        return borderLeftWidth();
1564    case RightToLeftWritingMode:
1565        return borderRightWidth();
1566    }
1567    ASSERT_NOT_REACHED();
1568    return borderTopWidth();
1569}
1570
1571unsigned short RenderStyle::borderAfterWidth() const
1572{
1573    switch (writingMode()) {
1574    case TopToBottomWritingMode:
1575        return borderBottomWidth();
1576    case BottomToTopWritingMode:
1577        return borderTopWidth();
1578    case LeftToRightWritingMode:
1579        return borderRightWidth();
1580    case RightToLeftWritingMode:
1581        return borderLeftWidth();
1582    }
1583    ASSERT_NOT_REACHED();
1584    return borderBottomWidth();
1585}
1586
1587unsigned short RenderStyle::borderStartWidth() const
1588{
1589    if (isHorizontalWritingMode())
1590        return isLeftToRightDirection() ? borderLeftWidth() : borderRightWidth();
1591    return isLeftToRightDirection() ? borderTopWidth() : borderBottomWidth();
1592}
1593
1594unsigned short RenderStyle::borderEndWidth() const
1595{
1596    if (isHorizontalWritingMode())
1597        return isLeftToRightDirection() ? borderRightWidth() : borderLeftWidth();
1598    return isLeftToRightDirection() ? borderBottomWidth() : borderTopWidth();
1599}
1600
1601void RenderStyle::setMarginStart(const Length& margin)
1602{
1603    if (isHorizontalWritingMode()) {
1604        if (isLeftToRightDirection())
1605            setMarginLeft(margin);
1606        else
1607            setMarginRight(margin);
1608    } else {
1609        if (isLeftToRightDirection())
1610            setMarginTop(margin);
1611        else
1612            setMarginBottom(margin);
1613    }
1614}
1615
1616void RenderStyle::setMarginEnd(const Length& margin)
1617{
1618    if (isHorizontalWritingMode()) {
1619        if (isLeftToRightDirection())
1620            setMarginRight(margin);
1621        else
1622            setMarginLeft(margin);
1623    } else {
1624        if (isLeftToRightDirection())
1625            setMarginBottom(margin);
1626        else
1627            setMarginTop(margin);
1628    }
1629}
1630
1631TextEmphasisMark RenderStyle::textEmphasisMark() const
1632{
1633    TextEmphasisMark mark = static_cast<TextEmphasisMark>(rareInheritedData->textEmphasisMark);
1634    if (mark != TextEmphasisMarkAuto)
1635        return mark;
1636
1637    if (isHorizontalWritingMode())
1638        return TextEmphasisMarkDot;
1639
1640    return TextEmphasisMarkSesame;
1641}
1642
1643Color RenderStyle::initialTapHighlightColor()
1644{
1645    return RenderTheme::tapHighlightColor();
1646}
1647
1648LayoutBoxExtent RenderStyle::imageOutsets(const NinePieceImage& image) const
1649{
1650    return LayoutBoxExtent(NinePieceImage::computeOutset(image.outset().top(), borderTopWidth()),
1651                           NinePieceImage::computeOutset(image.outset().right(), borderRightWidth()),
1652                           NinePieceImage::computeOutset(image.outset().bottom(), borderBottomWidth()),
1653                           NinePieceImage::computeOutset(image.outset().left(), borderLeftWidth()));
1654}
1655
1656void RenderStyle::setBorderImageSource(PassRefPtr<StyleImage> image)
1657{
1658    if (surround->border.m_image.image() == image.get())
1659        return;
1660    surround.access()->border.m_image.setImage(image);
1661}
1662
1663void RenderStyle::setBorderImageSlices(const LengthBox& slices)
1664{
1665    if (surround->border.m_image.imageSlices() == slices)
1666        return;
1667    surround.access()->border.m_image.setImageSlices(slices);
1668}
1669
1670void RenderStyle::setBorderImageWidth(const BorderImageLengthBox& slices)
1671{
1672    if (surround->border.m_image.borderSlices() == slices)
1673        return;
1674    surround.access()->border.m_image.setBorderSlices(slices);
1675}
1676
1677void RenderStyle::setBorderImageOutset(const BorderImageLengthBox& outset)
1678{
1679    if (surround->border.m_image.outset() == outset)
1680        return;
1681    surround.access()->border.m_image.setOutset(outset);
1682}
1683
1684float calcBorderRadiiConstraintScaleFor(const FloatRect& rect, const FloatRoundedRect::Radii& radii)
1685{
1686    // Constrain corner radii using CSS3 rules:
1687    // http://www.w3.org/TR/css3-background/#the-border-radius
1688
1689    float factor = 1;
1690    float radiiSum;
1691
1692    // top
1693    radiiSum = radii.topLeft().width() + radii.topRight().width(); // Casts to avoid integer overflow.
1694    if (radiiSum > rect.width())
1695        factor = std::min(rect.width() / radiiSum, factor);
1696
1697    // bottom
1698    radiiSum = radii.bottomLeft().width() + radii.bottomRight().width();
1699    if (radiiSum > rect.width())
1700        factor = std::min(rect.width() / radiiSum, factor);
1701
1702    // left
1703    radiiSum = radii.topLeft().height() + radii.bottomLeft().height();
1704    if (radiiSum > rect.height())
1705        factor = std::min(rect.height() / radiiSum, factor);
1706
1707    // right
1708    radiiSum = radii.topRight().height() + radii.bottomRight().height();
1709    if (radiiSum > rect.height())
1710        factor = std::min(rect.height() / radiiSum, factor);
1711
1712    ASSERT(factor <= 1);
1713    return factor;
1714}
1715
1716} // namespace WebCore
1717