Unreviewed, rolling out r213633.
[WebKit-https.git] / Source / WebCore / rendering / style / RenderStyle.cpp
1 /*
2  * Copyright (C) 1999 Antti Koivisto (koivisto@kde.org)
3  * Copyright (C) 2004-2017 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 "RenderStyle.h"
25
26 #include "ContentData.h"
27 #include "CSSCustomPropertyValue.h"
28 #include "CSSParser.h"
29 #include "CSSPropertyNames.h"
30 #include "CursorList.h"
31 #include "FloatRoundedRect.h"
32 #include "FontCascade.h"
33 #include "FontSelector.h"
34 #include "InlineTextBoxStyle.h"
35 #include "Pagination.h"
36 #include "QuotesData.h"
37 #include "RenderObject.h"
38 #include "RenderTheme.h"
39 #include "RuntimeEnabledFeatures.h"
40 #include "ScaleTransformOperation.h"
41 #include "ShadowData.h"
42 #include "StyleImage.h"
43 #include "StyleInheritedData.h"
44 #include "StyleResolver.h"
45 #include "StyleScrollSnapPoints.h"
46 #include "StyleSelfAlignmentData.h"
47 #include "StyleTreeResolver.h"
48 #include "WillChangeData.h"
49 #include <wtf/MathExtras.h>
50 #include <wtf/PointerComparison.h>
51 #include <wtf/StdLibExtras.h>
52 #include <algorithm>
53
54 #if ENABLE(TEXT_AUTOSIZING)
55 #include <wtf/text/StringHash.h>
56 #endif
57
58 namespace WebCore {
59
60 struct SameSizeAsBorderValue {
61     float m_width;
62     Color m_color;
63     int m_restBits;
64 };
65
66 COMPILE_ASSERT(sizeof(BorderValue) == sizeof(SameSizeAsBorderValue), BorderValue_should_not_grow);
67
68 struct SameSizeAsRenderStyle {
69     void* dataRefs[7];
70     void* ownPtrs[1];
71     void* dataRefSvgStyle;
72     struct InheritedFlags {
73         unsigned m_bitfields[2];
74     } m_inheritedFlags;
75
76     struct NonInheritedFlags {
77         uint64_t m_flags;
78     } m_nonInheritedFlags;
79 #if !ASSERT_DISABLED || ENABLE(SECURITY_ASSERTIONS)
80     bool deletionCheck;
81 #endif
82 };
83
84 COMPILE_ASSERT(sizeof(RenderStyle) == sizeof(SameSizeAsRenderStyle), RenderStyle_should_stay_small);
85
86 RenderStyle& RenderStyle::defaultStyle()
87 {
88     static NeverDestroyed<RenderStyle> style { CreateDefaultStyle };
89     return style;
90 }
91
92 RenderStyle RenderStyle::create()
93 {
94     return clone(defaultStyle());
95 }
96
97 std::unique_ptr<RenderStyle> RenderStyle::createPtr()
98 {
99     return clonePtr(defaultStyle());
100 }
101
102 RenderStyle RenderStyle::clone(const RenderStyle& style)
103 {
104     return RenderStyle(style, Clone);
105 }
106
107 std::unique_ptr<RenderStyle> RenderStyle::clonePtr(const RenderStyle& style)
108 {
109     return std::make_unique<RenderStyle>(style, Clone);
110 }
111
112 RenderStyle RenderStyle::createAnonymousStyleWithDisplay(const RenderStyle& parentStyle, EDisplay display)
113 {
114     auto newStyle = create();
115     newStyle.inheritFrom(parentStyle);
116     newStyle.inheritUnicodeBidiFrom(&parentStyle);
117     newStyle.setDisplay(display);
118     return newStyle;
119 }
120
121 RenderStyle RenderStyle::createStyleInheritingFromPseudoStyle(const RenderStyle& pseudoStyle)
122 {
123     ASSERT(pseudoStyle.styleType() == BEFORE || pseudoStyle.styleType() == AFTER);
124
125     auto style = create();
126     style.inheritFrom(pseudoStyle);
127     return style;
128 }
129
130 RenderStyle::RenderStyle(CreateDefaultStyleTag)
131     : m_boxData(StyleBoxData::create())
132     , m_visualData(StyleVisualData::create())
133     , m_backgroundData(StyleBackgroundData::create())
134     , m_surroundData(StyleSurroundData::create())
135     , m_rareNonInheritedData(StyleRareNonInheritedData::create())
136     , m_rareInheritedData(StyleRareInheritedData::create())
137     , m_inheritedData(StyleInheritedData::create())
138     , m_svgStyle(SVGRenderStyle::create())
139 {
140     m_inheritedFlags.emptyCells = initialEmptyCells();
141     m_inheritedFlags.captionSide = initialCaptionSide();
142     m_inheritedFlags.listStyleType = initialListStyleType();
143     m_inheritedFlags.listStylePosition = initialListStylePosition();
144     m_inheritedFlags.visibility = initialVisibility();
145     m_inheritedFlags.textAlign = initialTextAlign();
146     m_inheritedFlags.textTransform = initialTextTransform();
147     m_inheritedFlags.textDecorations = initialTextDecoration();
148     m_inheritedFlags.cursor = initialCursor();
149 #if ENABLE(CURSOR_VISIBILITY)
150     m_inheritedFlags.cursorVisibility = initialCursorVisibility();
151 #endif
152     m_inheritedFlags.direction = initialDirection();
153     m_inheritedFlags.whiteSpace = initialWhiteSpace();
154     m_inheritedFlags.borderCollapse = initialBorderCollapse();
155     m_inheritedFlags.rtlOrdering = initialRTLOrdering();
156     m_inheritedFlags.boxDirection = initialBoxDirection();
157     m_inheritedFlags.printColorAdjust = initialPrintColorAdjust();
158     m_inheritedFlags.pointerEvents = initialPointerEvents();
159     m_inheritedFlags.insideLink = NotInsideLink;
160     m_inheritedFlags.insideDefaultButton = false;
161     m_inheritedFlags.writingMode = initialWritingMode();
162
163     static_assert((sizeof(InheritedFlags) <= 8), "InheritedFlags does not grow");
164     static_assert((sizeof(NonInheritedFlags) <= 8), "NonInheritedFlags does not grow");
165 }
166
167 inline RenderStyle::RenderStyle(const RenderStyle& other, CloneTag)
168     : m_boxData(other.m_boxData)
169     , m_visualData(other.m_visualData)
170     , m_backgroundData(other.m_backgroundData)
171     , m_surroundData(other.m_surroundData)
172     , m_rareNonInheritedData(other.m_rareNonInheritedData)
173     , m_nonInheritedFlags(other.m_nonInheritedFlags)
174     , m_rareInheritedData(other.m_rareInheritedData)
175     , m_inheritedData(other.m_inheritedData)
176     , m_inheritedFlags(other.m_inheritedFlags)
177     , m_svgStyle(other.m_svgStyle)
178 {
179 }
180
181 inline RenderStyle::RenderStyle(RenderStyle& a, RenderStyle&& b)
182     : m_boxData(a.m_boxData.replace(WTFMove(b.m_boxData)))
183     , m_visualData(a.m_visualData.replace(WTFMove(b.m_visualData)))
184     , m_backgroundData(a.m_backgroundData.replace(WTFMove(b.m_backgroundData)))
185     , m_surroundData(a.m_surroundData.replace(WTFMove(b.m_surroundData)))
186     , m_rareNonInheritedData(a.m_rareNonInheritedData.replace(WTFMove(b.m_rareNonInheritedData)))
187     , m_nonInheritedFlags(std::exchange(a.m_nonInheritedFlags, b.m_nonInheritedFlags))
188     , m_rareInheritedData(a.m_rareInheritedData.replace(WTFMove(b.m_rareInheritedData)))
189     , m_inheritedData(a.m_inheritedData.replace(WTFMove(b.m_inheritedData)))
190     , m_inheritedFlags(std::exchange(a.m_inheritedFlags, b.m_inheritedFlags))
191     , m_cachedPseudoStyles(std::exchange(a.m_cachedPseudoStyles, WTFMove(b.m_cachedPseudoStyles)))
192     , m_svgStyle(a.m_svgStyle.replace(WTFMove(b.m_svgStyle)))
193 {
194 }
195
196 RenderStyle::~RenderStyle()
197 {
198 #if !ASSERT_DISABLED || ENABLE(SECURITY_ASSERTIONS)
199     ASSERT_WITH_SECURITY_IMPLICATION(!m_deletionHasBegun);
200     m_deletionHasBegun = true;
201 #endif
202 }
203
204 RenderStyle RenderStyle::replace(RenderStyle&& newStyle)
205 {
206     return RenderStyle { *this, WTFMove(newStyle) };
207 }
208
209 bool RenderStyle::isCSSGridLayoutEnabled()
210 {
211     return RuntimeEnabledFeatures::sharedFeatures().isCSSGridLayoutEnabled();
212 }
213
214 static StyleSelfAlignmentData resolvedSelfAlignment(const StyleSelfAlignmentData& value, ItemPosition normalValueBehavior)
215 {
216     if (value.position() == ItemPositionNormal || value.position() == ItemPositionAuto)
217         return { normalValueBehavior, OverflowAlignmentDefault };
218     return value;
219 }
220
221 StyleSelfAlignmentData RenderStyle::resolvedAlignItems(ItemPosition normalValueBehaviour) const
222 {
223     return resolvedSelfAlignment(alignItems(), normalValueBehaviour);
224 }
225
226 StyleSelfAlignmentData RenderStyle::resolvedAlignSelf(const RenderStyle* parentStyle, ItemPosition normalValueBehaviour) const
227 {
228     // The auto keyword computes to the parent's align-items computed value.
229     // We will return the behaviour of 'normal' value if needed, which is specific of each layout model.
230     if (!parentStyle || alignSelf().position() != ItemPositionAuto)
231         return resolvedSelfAlignment(alignSelf(), normalValueBehaviour);
232     return parentStyle->resolvedAlignItems(normalValueBehaviour);
233 }
234
235 StyleSelfAlignmentData RenderStyle::resolvedJustifyItems(ItemPosition normalValueBehaviour) const
236 {
237     // FIXME: justify-items 'auto' value is allowed only to provide the 'legacy' keyword's behavior, which it's still not implemented for layout.
238     // "If the inherited value of justify-items includes the legacy keyword, auto computes to the inherited value."
239     // https://drafts.csswg.org/css-align/#justify-items-property
240     if (justifyItems().position() == ItemPositionAuto)
241         return { normalValueBehaviour, OverflowAlignmentDefault };
242     return resolvedSelfAlignment(justifyItems(), normalValueBehaviour);
243 }
244
245 StyleSelfAlignmentData RenderStyle::resolvedJustifySelf(const RenderStyle* parentStyle, ItemPosition normalValueBehaviour) const
246 {
247     // The auto keyword computes to the parent's justify-items computed value.
248     // We will return the behaviour of 'normal' value if needed, which is specific of each layout model.
249     if (!parentStyle || justifySelf().position() != ItemPositionAuto)
250         return resolvedSelfAlignment(justifySelf(), normalValueBehaviour);
251     return parentStyle->resolvedJustifyItems(normalValueBehaviour);
252 }
253
254 static inline ContentPosition resolvedContentAlignmentPosition(const StyleContentAlignmentData& value, const StyleContentAlignmentData& normalValueBehavior)
255 {
256     return (value.position() == ContentPositionNormal && value.distribution() == ContentDistributionDefault) ? normalValueBehavior.position() : value.position();
257 }
258
259 static inline ContentDistributionType resolvedContentAlignmentDistribution(const StyleContentAlignmentData& value, const StyleContentAlignmentData& normalValueBehavior)
260 {
261     return (value.position() == ContentPositionNormal && value.distribution() == ContentDistributionDefault) ? normalValueBehavior.distribution() : value.distribution();
262 }
263
264 ContentPosition RenderStyle::resolvedJustifyContentPosition(const StyleContentAlignmentData& normalValueBehavior) const
265 {
266     return resolvedContentAlignmentPosition(justifyContent(), normalValueBehavior);
267 }
268
269 ContentDistributionType RenderStyle::resolvedJustifyContentDistribution(const StyleContentAlignmentData& normalValueBehavior) const
270 {
271     return resolvedContentAlignmentDistribution(justifyContent(), normalValueBehavior);
272 }
273
274 ContentPosition RenderStyle::resolvedAlignContentPosition(const StyleContentAlignmentData& normalValueBehavior) const
275 {
276     return resolvedContentAlignmentPosition(alignContent(), normalValueBehavior);
277 }
278
279 ContentDistributionType RenderStyle::resolvedAlignContentDistribution(const StyleContentAlignmentData& normalValueBehavior) const
280 {
281     return resolvedContentAlignmentDistribution(alignContent(), normalValueBehavior);
282 }
283
284 void RenderStyle::inheritFrom(const RenderStyle& inheritParent)
285 {
286     m_rareInheritedData = inheritParent.m_rareInheritedData;
287     m_inheritedData = inheritParent.m_inheritedData;
288     m_inheritedFlags = inheritParent.m_inheritedFlags;
289
290     if (m_svgStyle != inheritParent.m_svgStyle)
291         m_svgStyle.access().inheritFrom(inheritParent.m_svgStyle.get());
292 }
293
294 void RenderStyle::copyNonInheritedFrom(const RenderStyle& other)
295 {
296     m_boxData = other.m_boxData;
297     m_visualData = other.m_visualData;
298     m_backgroundData = other.m_backgroundData;
299     m_surroundData = other.m_surroundData;
300     m_rareNonInheritedData = other.m_rareNonInheritedData;
301     m_nonInheritedFlags.copyNonInheritedFrom(other.m_nonInheritedFlags);
302
303     if (m_svgStyle != other.m_svgStyle)
304         m_svgStyle.access().copyNonInheritedFrom(other.m_svgStyle.get());
305
306     ASSERT(zoom() == initialZoom());
307 }
308
309 bool RenderStyle::operator==(const RenderStyle& other) const
310 {
311     // compare everything except the pseudoStyle pointer
312     return m_inheritedFlags == other.m_inheritedFlags
313         && m_nonInheritedFlags == other.m_nonInheritedFlags
314         && m_boxData == other.m_boxData
315         && m_visualData == other.m_visualData
316         && m_backgroundData == other.m_backgroundData
317         && m_surroundData == other.m_surroundData
318         && m_rareNonInheritedData == other.m_rareNonInheritedData
319         && m_rareInheritedData == other.m_rareInheritedData
320         && m_inheritedData == other.m_inheritedData
321         && m_svgStyle == other.m_svgStyle;
322 }
323
324 bool RenderStyle::hasUniquePseudoStyle() const
325 {
326     if (!m_cachedPseudoStyles || styleType() != NOPSEUDO)
327         return false;
328
329     for (auto& pseudoStyle : *m_cachedPseudoStyles) {
330         if (pseudoStyle->unique())
331             return true;
332     }
333
334     return false;
335 }
336
337 RenderStyle* RenderStyle::getCachedPseudoStyle(PseudoId pid) const
338 {
339     if (!m_cachedPseudoStyles || !m_cachedPseudoStyles->size())
340         return nullptr;
341
342     if (styleType() != NOPSEUDO) 
343         return nullptr;
344
345     for (auto& pseudoStyle : *m_cachedPseudoStyles) {
346         if (pseudoStyle->styleType() == pid)
347             return pseudoStyle.get();
348     }
349
350     return nullptr;
351 }
352
353 RenderStyle* RenderStyle::addCachedPseudoStyle(std::unique_ptr<RenderStyle> pseudo)
354 {
355     if (!pseudo)
356         return nullptr;
357
358     ASSERT(pseudo->styleType() > NOPSEUDO);
359
360     RenderStyle* result = pseudo.get();
361
362     if (!m_cachedPseudoStyles)
363         m_cachedPseudoStyles = std::make_unique<PseudoStyleCache>();
364
365     m_cachedPseudoStyles->append(WTFMove(pseudo));
366
367     return result;
368 }
369
370 void RenderStyle::removeCachedPseudoStyle(PseudoId pid)
371 {
372     if (!m_cachedPseudoStyles)
373         return;
374     for (size_t i = 0; i < m_cachedPseudoStyles->size(); ++i) {
375         RenderStyle* pseudoStyle = m_cachedPseudoStyles->at(i).get();
376         if (pseudoStyle->styleType() == pid) {
377             m_cachedPseudoStyles->remove(i);
378             return;
379         }
380     }
381 }
382
383 bool RenderStyle::inheritedNotEqual(const RenderStyle* other) const
384 {
385     return m_inheritedFlags != other->m_inheritedFlags
386         || m_inheritedData != other->m_inheritedData
387         || m_svgStyle->inheritedNotEqual(other->m_svgStyle)
388         || m_rareInheritedData != other->m_rareInheritedData;
389 }
390
391 #if ENABLE(TEXT_AUTOSIZING)
392
393 static inline unsigned computeFontHash(const FontCascade& font)
394 {
395     IntegerHasher hasher;
396     hasher.add(ASCIICaseInsensitiveHash::hash(font.fontDescription().firstFamily()));
397     hasher.add(font.fontDescription().specifiedSize());
398     return hasher.hash();
399 }
400
401 unsigned RenderStyle::hashForTextAutosizing() const
402 {
403     // FIXME: Not a very smart hash. Could be improved upon. See <https://bugs.webkit.org/show_bug.cgi?id=121131>.
404     unsigned hash = m_rareNonInheritedData->appearance;
405     hash ^= m_rareNonInheritedData->marginBeforeCollapse;
406     hash ^= m_rareNonInheritedData->marginAfterCollapse;
407     hash ^= m_rareNonInheritedData->lineClamp.value();
408     hash ^= m_rareInheritedData->overflowWrap;
409     hash ^= m_rareInheritedData->nbspMode;
410     hash ^= m_rareInheritedData->lineBreak;
411     hash ^= WTF::FloatHash<float>::hash(m_inheritedData->specifiedLineHeight.value());
412     hash ^= computeFontHash(m_inheritedData->fontCascade);
413     hash ^= WTF::FloatHash<float>::hash(m_inheritedData->horizontalBorderSpacing);
414     hash ^= WTF::FloatHash<float>::hash(m_inheritedData->verticalBorderSpacing);
415     hash ^= m_inheritedFlags.boxDirection;
416     hash ^= m_inheritedFlags.rtlOrdering;
417     hash ^= m_nonInheritedFlags.position();
418     hash ^= m_nonInheritedFlags.floating();
419     hash ^= m_rareNonInheritedData->textOverflow;
420     hash ^= m_rareInheritedData->textSecurity;
421     return hash;
422 }
423
424 bool RenderStyle::equalForTextAutosizing(const RenderStyle& other) const
425 {
426     return m_rareNonInheritedData->appearance == other.m_rareNonInheritedData->appearance
427         && m_rareNonInheritedData->marginBeforeCollapse == other.m_rareNonInheritedData->marginBeforeCollapse
428         && m_rareNonInheritedData->marginAfterCollapse == other.m_rareNonInheritedData->marginAfterCollapse
429         && m_rareNonInheritedData->lineClamp == other.m_rareNonInheritedData->lineClamp
430         && m_rareInheritedData->textSizeAdjust == other.m_rareInheritedData->textSizeAdjust
431         && m_rareInheritedData->overflowWrap == other.m_rareInheritedData->overflowWrap
432         && m_rareInheritedData->nbspMode == other.m_rareInheritedData->nbspMode
433         && m_rareInheritedData->lineBreak == other.m_rareInheritedData->lineBreak
434         && m_rareInheritedData->textSecurity == other.m_rareInheritedData->textSecurity
435         && m_inheritedData->specifiedLineHeight == other.m_inheritedData->specifiedLineHeight
436         && m_inheritedData->fontCascade.equalForTextAutoSizing(other.m_inheritedData->fontCascade)
437         && m_inheritedData->horizontalBorderSpacing == other.m_inheritedData->horizontalBorderSpacing
438         && m_inheritedData->verticalBorderSpacing == other.m_inheritedData->verticalBorderSpacing
439         && m_inheritedFlags.boxDirection == other.m_inheritedFlags.boxDirection
440         && m_inheritedFlags.rtlOrdering == other.m_inheritedFlags.rtlOrdering
441         && m_nonInheritedFlags.position() == other.m_nonInheritedFlags.position()
442         && m_nonInheritedFlags.floating() == other.m_nonInheritedFlags.floating()
443         && m_rareNonInheritedData->textOverflow == other.m_rareNonInheritedData->textOverflow;
444 }
445
446 #endif // ENABLE(TEXT_AUTOSIZING)
447
448 bool RenderStyle::inheritedDataShared(const RenderStyle* other) const
449 {
450     // This is a fast check that only looks if the data structures are shared.
451     return m_inheritedFlags == other->m_inheritedFlags
452         && m_inheritedData.get() == other->m_inheritedData.get()
453         && m_svgStyle.get() == other->m_svgStyle.get()
454         && m_rareInheritedData.get() == other->m_rareInheritedData.get();
455 }
456
457 static bool positionChangeIsMovementOnly(const LengthBox& a, const LengthBox& b, const Length& width)
458 {
459     // If any unit types are different, then we can't guarantee
460     // that this was just a movement.
461     if (a.left().type() != b.left().type()
462         || a.right().type() != b.right().type()
463         || a.top().type() != b.top().type()
464         || a.bottom().type() != b.bottom().type())
465         return false;
466
467     // Only one unit can be non-auto in the horizontal direction and
468     // in the vertical direction.  Otherwise the adjustment of values
469     // is changing the size of the box.
470     if (!a.left().isIntrinsicOrAuto() && !a.right().isIntrinsicOrAuto())
471         return false;
472     if (!a.top().isIntrinsicOrAuto() && !a.bottom().isIntrinsicOrAuto())
473         return false;
474     // If our width is auto and left or right is specified then this 
475     // is not just a movement - we need to resize to our container.
476     if ((!a.left().isIntrinsicOrAuto() || !a.right().isIntrinsicOrAuto()) && width.isIntrinsicOrAuto())
477         return false;
478
479     // One of the units is fixed or percent in both directions and stayed
480     // that way in the new style.  Therefore all we are doing is moving.
481     return true;
482 }
483
484 inline bool RenderStyle::changeAffectsVisualOverflow(const RenderStyle& other) const
485 {
486     if (m_rareNonInheritedData.get() != other.m_rareNonInheritedData.get()
487         && !arePointingToEqualData(m_rareNonInheritedData->boxShadow, other.m_rareNonInheritedData->boxShadow))
488         return true;
489
490     if (m_rareInheritedData.get() != other.m_rareInheritedData.get()
491         && !arePointingToEqualData(m_rareInheritedData->textShadow, other.m_rareInheritedData->textShadow))
492         return true;
493
494     if (m_inheritedFlags.textDecorations != other.m_inheritedFlags.textDecorations
495         || m_visualData->textDecoration != other.m_visualData->textDecoration
496         || m_rareNonInheritedData->textDecorationStyle != other.m_rareNonInheritedData->textDecorationStyle) {
497         // Underlines are always drawn outside of their textbox bounds when text-underline-position: under;
498         // is specified. We can take an early out here.
499         if (textUnderlinePosition() == TextUnderlinePositionUnder
500             || other.textUnderlinePosition() == TextUnderlinePositionUnder)
501             return true;
502         return visualOverflowForDecorations(*this, nullptr) != visualOverflowForDecorations(other, nullptr);
503     }
504
505     if (hasOutlineInVisualOverflow() != other.hasOutlineInVisualOverflow())
506         return true;
507     return false;
508 }
509
510 bool RenderStyle::changeRequiresLayout(const RenderStyle& other, unsigned& changedContextSensitiveProperties) const
511 {
512     if (m_boxData->width() != other.m_boxData->width()
513         || m_boxData->minWidth() != other.m_boxData->minWidth()
514         || m_boxData->maxWidth() != other.m_boxData->maxWidth()
515         || m_boxData->height() != other.m_boxData->height()
516         || m_boxData->minHeight() != other.m_boxData->minHeight()
517         || m_boxData->maxHeight() != other.m_boxData->maxHeight())
518         return true;
519
520     if (m_boxData->verticalAlign() != other.m_boxData->verticalAlign() || m_nonInheritedFlags.verticalAlign() != other.m_nonInheritedFlags.verticalAlign())
521         return true;
522
523     if (m_boxData->boxSizing() != other.m_boxData->boxSizing())
524         return true;
525
526     if (m_surroundData->margin != other.m_surroundData->margin)
527         return true;
528
529     if (m_surroundData->padding != other.m_surroundData->padding)
530         return true;
531
532     // FIXME: We should add an optimized form of layout that just recomputes visual overflow.
533     if (changeAffectsVisualOverflow(other))
534         return true;
535
536     if (m_rareNonInheritedData.get() != other.m_rareNonInheritedData.get()) {
537         if (m_rareNonInheritedData->appearance != other.m_rareNonInheritedData->appearance
538             || m_rareNonInheritedData->marginBeforeCollapse != other.m_rareNonInheritedData->marginBeforeCollapse
539             || m_rareNonInheritedData->marginAfterCollapse != other.m_rareNonInheritedData->marginAfterCollapse
540             || m_rareNonInheritedData->lineClamp != other.m_rareNonInheritedData->lineClamp
541             || m_rareNonInheritedData->initialLetter != other.m_rareNonInheritedData->initialLetter
542             || m_rareNonInheritedData->textOverflow != other.m_rareNonInheritedData->textOverflow)
543             return true;
544
545         if (m_rareNonInheritedData->regionFragment != other.m_rareNonInheritedData->regionFragment)
546             return true;
547
548         if (m_rareNonInheritedData->shapeMargin != other.m_rareNonInheritedData->shapeMargin)
549             return true;
550
551         if (m_rareNonInheritedData->deprecatedFlexibleBox != other.m_rareNonInheritedData->deprecatedFlexibleBox)
552             return true;
553
554         if (m_rareNonInheritedData->flexibleBox != other.m_rareNonInheritedData->flexibleBox)
555             return true;
556
557         if (m_rareNonInheritedData->order != other.m_rareNonInheritedData->order
558             || m_rareNonInheritedData->alignContent != other.m_rareNonInheritedData->alignContent
559             || m_rareNonInheritedData->alignItems != other.m_rareNonInheritedData->alignItems
560             || m_rareNonInheritedData->alignSelf != other.m_rareNonInheritedData->alignSelf
561             || m_rareNonInheritedData->justifyContent != other.m_rareNonInheritedData->justifyContent
562             || m_rareNonInheritedData->justifyItems != other.m_rareNonInheritedData->justifyItems
563             || m_rareNonInheritedData->justifySelf != other.m_rareNonInheritedData->justifySelf)
564             return true;
565
566         if (!arePointingToEqualData(m_rareNonInheritedData->boxReflect, other.m_rareNonInheritedData->boxReflect))
567             return true;
568
569         if (m_rareNonInheritedData->multiCol != other.m_rareNonInheritedData->multiCol)
570             return true;
571
572         if (m_rareNonInheritedData->transform != other.m_rareNonInheritedData->transform) {
573             if (m_rareNonInheritedData->transform->hasTransform() != other.m_rareNonInheritedData->transform->hasTransform())
574                 return true;
575             if (*m_rareNonInheritedData->transform != *other.m_rareNonInheritedData->transform) {
576                 changedContextSensitiveProperties |= ContextSensitivePropertyTransform;
577                 // Don't return; keep looking for another change
578             }
579         }
580
581         if (m_rareNonInheritedData->grid != other.m_rareNonInheritedData->grid
582             || m_rareNonInheritedData->gridItem != other.m_rareNonInheritedData->gridItem)
583             return true;
584
585 #if ENABLE(DASHBOARD_SUPPORT)
586         // If regions change, trigger a relayout to re-calc regions.
587         if (m_rareNonInheritedData->dashboardRegions != other.m_rareNonInheritedData->dashboardRegions)
588             return true;
589 #endif
590
591         if (!arePointingToEqualData(m_rareNonInheritedData->willChange, other.m_rareNonInheritedData->willChange)) {
592             changedContextSensitiveProperties |= ContextSensitivePropertyWillChange;
593             // Don't return; keep looking for another change
594         }
595     }
596
597     if (m_rareInheritedData.get() != other.m_rareInheritedData.get()) {
598         if (m_rareInheritedData->indent != other.m_rareInheritedData->indent
599 #if ENABLE(CSS3_TEXT)
600             || m_rareInheritedData->textAlignLast != other.m_rareInheritedData->textAlignLast
601             || m_rareInheritedData->textJustify != other.m_rareInheritedData->textJustify
602             || m_rareInheritedData->textIndentLine != other.m_rareInheritedData->textIndentLine
603 #endif
604             || m_rareInheritedData->effectiveZoom != other.m_rareInheritedData->effectiveZoom
605             || m_rareInheritedData->textZoom != other.m_rareInheritedData->textZoom
606 #if ENABLE(TEXT_AUTOSIZING)
607             || m_rareInheritedData->textSizeAdjust != other.m_rareInheritedData->textSizeAdjust
608 #endif
609             || m_rareInheritedData->wordBreak != other.m_rareInheritedData->wordBreak
610             || m_rareInheritedData->overflowWrap != other.m_rareInheritedData->overflowWrap
611             || m_rareInheritedData->nbspMode != other.m_rareInheritedData->nbspMode
612             || m_rareInheritedData->lineBreak != other.m_rareInheritedData->lineBreak
613             || m_rareInheritedData->textSecurity != other.m_rareInheritedData->textSecurity
614             || m_rareInheritedData->hyphens != other.m_rareInheritedData->hyphens
615             || m_rareInheritedData->hyphenationLimitBefore != other.m_rareInheritedData->hyphenationLimitBefore
616             || m_rareInheritedData->hyphenationLimitAfter != other.m_rareInheritedData->hyphenationLimitAfter
617             || m_rareInheritedData->hyphenationString != other.m_rareInheritedData->hyphenationString
618             || m_rareInheritedData->rubyPosition != other.m_rareInheritedData->rubyPosition
619             || m_rareInheritedData->textEmphasisMark != other.m_rareInheritedData->textEmphasisMark
620             || m_rareInheritedData->textEmphasisPosition != other.m_rareInheritedData->textEmphasisPosition
621             || m_rareInheritedData->textEmphasisCustomMark != other.m_rareInheritedData->textEmphasisCustomMark
622             || m_rareInheritedData->textOrientation != other.m_rareInheritedData->textOrientation
623             || m_rareInheritedData->tabSize != other.m_rareInheritedData->tabSize
624             || m_rareInheritedData->lineBoxContain != other.m_rareInheritedData->lineBoxContain
625             || m_rareInheritedData->lineGrid != other.m_rareInheritedData->lineGrid
626 #if ENABLE(CSS_IMAGE_ORIENTATION)
627             || m_rareInheritedData->imageOrientation != other.m_rareInheritedData->imageOrientation
628 #endif
629 #if ENABLE(CSS_IMAGE_RESOLUTION)
630             || m_rareInheritedData->imageResolutionSource != other.m_rareInheritedData->imageResolutionSource
631             || m_rareInheritedData->imageResolutionSnap != other.m_rareInheritedData->imageResolutionSnap
632             || m_rareInheritedData->imageResolution != other.m_rareInheritedData->imageResolution
633 #endif
634             || m_rareInheritedData->lineSnap != other.m_rareInheritedData->lineSnap
635             || m_rareInheritedData->lineAlign != other.m_rareInheritedData->lineAlign
636             || m_rareInheritedData->hangingPunctuation != other.m_rareInheritedData->hangingPunctuation
637 #if ENABLE(ACCELERATED_OVERFLOW_SCROLLING)
638             || m_rareInheritedData->useTouchOverflowScrolling != other.m_rareInheritedData->useTouchOverflowScrolling
639 #endif
640             || m_rareInheritedData->listStyleImage != other.m_rareInheritedData->listStyleImage) // FIXME: needs arePointingToEqualData()?
641             return true;
642
643         if (textStrokeWidth() != other.textStrokeWidth())
644             return true;
645     }
646
647     if (m_inheritedData->lineHeight != other.m_inheritedData->lineHeight
648 #if ENABLE(TEXT_AUTOSIZING)
649         || m_inheritedData->specifiedLineHeight != other.m_inheritedData->specifiedLineHeight
650 #endif
651         || m_inheritedData->fontCascade != other.m_inheritedData->fontCascade
652         || m_inheritedData->horizontalBorderSpacing != other.m_inheritedData->horizontalBorderSpacing
653         || m_inheritedData->verticalBorderSpacing != other.m_inheritedData->verticalBorderSpacing
654         || m_inheritedFlags.boxDirection != other.m_inheritedFlags.boxDirection
655         || m_inheritedFlags.rtlOrdering != other.m_inheritedFlags.rtlOrdering
656         || m_nonInheritedFlags.position() != other.m_nonInheritedFlags.position()
657         || m_nonInheritedFlags.floating() != other.m_nonInheritedFlags.floating()
658         || m_nonInheritedFlags.originalDisplay() != other.m_nonInheritedFlags.originalDisplay())
659         return true;
660
661
662     if ((m_nonInheritedFlags.effectiveDisplay()) >= TABLE) {
663         if (m_inheritedFlags.borderCollapse != other.m_inheritedFlags.borderCollapse
664             || m_inheritedFlags.emptyCells != other.m_inheritedFlags.emptyCells
665             || m_inheritedFlags.captionSide != other.m_inheritedFlags.captionSide
666             || m_nonInheritedFlags.tableLayout() != other.m_nonInheritedFlags.tableLayout())
667             return true;
668
669         // In the collapsing border model, 'hidden' suppresses other borders, while 'none'
670         // does not, so these style differences can be width differences.
671         if (m_inheritedFlags.borderCollapse
672             && ((borderTopStyle() == BHIDDEN && other.borderTopStyle() == BNONE)
673                 || (borderTopStyle() == BNONE && other.borderTopStyle() == BHIDDEN)
674                 || (borderBottomStyle() == BHIDDEN && other.borderBottomStyle() == BNONE)
675                 || (borderBottomStyle() == BNONE && other.borderBottomStyle() == BHIDDEN)
676                 || (borderLeftStyle() == BHIDDEN && other.borderLeftStyle() == BNONE)
677                 || (borderLeftStyle() == BNONE && other.borderLeftStyle() == BHIDDEN)
678                 || (borderRightStyle() == BHIDDEN && other.borderRightStyle() == BNONE)
679                 || (borderRightStyle() == BNONE && other.borderRightStyle() == BHIDDEN)))
680             return true;
681     }
682
683     if (m_nonInheritedFlags.effectiveDisplay() == LIST_ITEM) {
684         if (m_inheritedFlags.listStyleType != other.m_inheritedFlags.listStyleType
685             || m_inheritedFlags.listStylePosition != other.m_inheritedFlags.listStylePosition)
686             return true;
687     }
688
689     if (m_inheritedFlags.textAlign != other.m_inheritedFlags.textAlign
690         || m_inheritedFlags.textTransform != other.m_inheritedFlags.textTransform
691         || m_inheritedFlags.direction != other.m_inheritedFlags.direction
692         || m_inheritedFlags.whiteSpace != other.m_inheritedFlags.whiteSpace
693         || m_nonInheritedFlags.clear() != other.m_nonInheritedFlags.clear()
694         || m_nonInheritedFlags.unicodeBidi() != other.m_nonInheritedFlags.unicodeBidi())
695         return true;
696
697     // Check block flow direction.
698     if (m_inheritedFlags.writingMode != other.m_inheritedFlags.writingMode)
699         return true;
700
701     // Check text combine mode.
702     if (m_rareNonInheritedData->textCombine != other.m_rareNonInheritedData->textCombine)
703         return true;
704
705     // Check breaks.
706     if (m_rareNonInheritedData->breakBefore != other.m_rareNonInheritedData->breakBefore
707         || m_rareNonInheritedData->breakAfter != other.m_rareNonInheritedData->breakAfter
708         || m_rareNonInheritedData->breakInside != other.m_rareNonInheritedData->breakInside)
709         return true;
710
711     // Overflow returns a layout hint.
712     if (m_nonInheritedFlags.overflowX() != other.m_nonInheritedFlags.overflowX()
713         || m_nonInheritedFlags.overflowY() != other.m_nonInheritedFlags.overflowY())
714         return true;
715
716     // If our border widths change, then we need to layout.  Other changes to borders
717     // only necessitate a repaint.
718     if (borderLeftWidth() != other.borderLeftWidth()
719         || borderTopWidth() != other.borderTopWidth()
720         || borderBottomWidth() != other.borderBottomWidth()
721         || borderRightWidth() != other.borderRightWidth())
722         return true;
723
724     // If the counter directives change, trigger a relayout to re-calculate counter values and rebuild the counter node tree.
725     if (!arePointingToEqualData(m_rareNonInheritedData->counterDirectives, other.m_rareNonInheritedData->counterDirectives))
726         return true;
727
728     if ((visibility() == COLLAPSE) != (other.visibility() == COLLAPSE))
729         return true;
730
731     if (m_rareNonInheritedData->hasOpacity() != other.m_rareNonInheritedData->hasOpacity()) {
732         // FIXME: We would like to use SimplifiedLayout here, but we can't quite do that yet.
733         // We need to make sure SimplifiedLayout can operate correctly on RenderInlines (we will need
734         // to add a selfNeedsSimplifiedLayout bit in order to not get confused and taint every line).
735         // In addition we need to solve the floating object issue when layers come and go. Right now
736         // a full layout is necessary to keep floating object lists sane.
737         return true;
738     }
739
740     if (m_rareNonInheritedData->hasFilters() != other.m_rareNonInheritedData->hasFilters())
741         return true;
742
743 #if ENABLE(FILTERS_LEVEL_2)
744     if (m_rareNonInheritedData->hasBackdropFilters() != other.m_rareNonInheritedData->hasBackdropFilters())
745         return true;
746 #endif
747
748     if (!arePointingToEqualData(m_rareInheritedData->quotes, other.m_rareInheritedData->quotes))
749         return true;
750
751     if (position() != StaticPosition) {
752         if (m_surroundData->offset != other.m_surroundData->offset) {
753             // FIXME: We would like to use SimplifiedLayout for relative positioning, but we can't quite do that yet.
754             // We need to make sure SimplifiedLayout can operate correctly on RenderInlines (we will need
755             // to add a selfNeedsSimplifiedLayout bit in order to not get confused and taint every line).
756             if (position() != AbsolutePosition)
757                 return true;
758
759             // Optimize for the case where a positioned layer is moving but not changing size.
760             if (!positionChangeIsMovementOnly(m_surroundData->offset, other.m_surroundData->offset, m_boxData->width()))
761                 return true;
762         }
763     }
764
765     bool hasFirstLineStyle = hasPseudoStyle(FIRST_LINE);
766     if (hasFirstLineStyle != other.hasPseudoStyle(FIRST_LINE))
767         return true;
768     if (hasFirstLineStyle) {
769         auto* firstLineStyle = getCachedPseudoStyle(FIRST_LINE);
770         if (!firstLineStyle)
771             return true;
772         auto* otherFirstLineStyle = other.getCachedPseudoStyle(FIRST_LINE);
773         if (!otherFirstLineStyle)
774             return true;
775         // FIXME: Not all first line style changes actually need layout.
776         if (*firstLineStyle != *otherFirstLineStyle)
777             return true;
778     }
779
780     return false;
781 }
782
783 bool RenderStyle::changeRequiresPositionedLayoutOnly(const RenderStyle& other, unsigned&) const
784 {
785     if (position() == StaticPosition)
786         return false;
787
788     if (m_surroundData->offset != other.m_surroundData->offset) {
789         // Optimize for the case where a positioned layer is moving but not changing size.
790         if (position() == AbsolutePosition && positionChangeIsMovementOnly(m_surroundData->offset, other.m_surroundData->offset, m_boxData->width()))
791             return true;
792     }
793     
794     return false;
795 }
796
797 bool RenderStyle::changeRequiresLayerRepaint(const RenderStyle& other, unsigned& changedContextSensitiveProperties) const
798 {
799     // StyleResolver has ensured that zIndex is non-auto only if it's applicable.
800     if (m_boxData->zIndex() != other.m_boxData->zIndex() || m_boxData->hasAutoZIndex() != other.m_boxData->hasAutoZIndex())
801         return true;
802
803     if (position() != StaticPosition) {
804         if (m_visualData->clip != other.m_visualData->clip || m_visualData->hasClip != other.m_visualData->hasClip) {
805             changedContextSensitiveProperties |= ContextSensitivePropertyClipRect;
806             return true;
807         }
808     }
809
810 #if ENABLE(CSS_COMPOSITING)
811     if (m_rareNonInheritedData->effectiveBlendMode != other.m_rareNonInheritedData->effectiveBlendMode)
812         return true;
813 #endif
814
815     if (m_rareNonInheritedData->opacity != other.m_rareNonInheritedData->opacity) {
816         changedContextSensitiveProperties |= ContextSensitivePropertyOpacity;
817         // Don't return; keep looking for another change.
818     }
819
820     if (m_rareNonInheritedData->filter != other.m_rareNonInheritedData->filter) {
821         changedContextSensitiveProperties |= ContextSensitivePropertyFilter;
822         // Don't return; keep looking for another change.
823     }
824
825 #if ENABLE(FILTERS_LEVEL_2)
826     if (m_rareNonInheritedData->backdropFilter != other.m_rareNonInheritedData->backdropFilter) {
827         changedContextSensitiveProperties |= ContextSensitivePropertyFilter;
828         // Don't return; keep looking for another change.
829     }
830 #endif
831
832     if (m_rareNonInheritedData->mask != other.m_rareNonInheritedData->mask
833         || m_rareNonInheritedData->maskBoxImage != other.m_rareNonInheritedData->maskBoxImage)
834         return true;
835
836     return false;
837 }
838
839 bool RenderStyle::changeRequiresRepaint(const RenderStyle& other, unsigned& changedContextSensitiveProperties) const
840 {
841     if (m_inheritedFlags.visibility != other.m_inheritedFlags.visibility
842         || m_inheritedFlags.printColorAdjust != other.m_inheritedFlags.printColorAdjust
843         || m_inheritedFlags.insideLink != other.m_inheritedFlags.insideLink
844         || m_inheritedFlags.insideDefaultButton != other.m_inheritedFlags.insideDefaultButton
845         || m_surroundData->border != other.m_surroundData->border
846         || !m_backgroundData->isEquivalentForPainting(*other.m_backgroundData)
847         || m_rareInheritedData->userModify != other.m_rareInheritedData->userModify
848         || m_rareInheritedData->userSelect != other.m_rareInheritedData->userSelect
849         || m_rareNonInheritedData->userDrag != other.m_rareNonInheritedData->userDrag
850         || m_rareNonInheritedData->borderFit != other.m_rareNonInheritedData->borderFit
851         || m_rareNonInheritedData->objectFit != other.m_rareNonInheritedData->objectFit
852         || m_rareNonInheritedData->objectPosition != other.m_rareNonInheritedData->objectPosition
853         || m_rareInheritedData->imageRendering != other.m_rareInheritedData->imageRendering)
854         return true;
855
856     if (m_rareNonInheritedData->shapeOutside != other.m_rareNonInheritedData->shapeOutside)
857         return true;
858
859     // FIXME: this should probably be moved to changeRequiresLayerRepaint().
860     if (m_rareNonInheritedData->clipPath != other.m_rareNonInheritedData->clipPath) {
861         changedContextSensitiveProperties |= ContextSensitivePropertyClipPath;
862         // Don't return; keep looking for another change.
863     }
864
865     return false;
866 }
867
868 bool RenderStyle::changeRequiresRepaintIfTextOrBorderOrOutline(const RenderStyle& other, unsigned&) const
869 {
870     if (m_inheritedData->color != other.m_inheritedData->color
871         || m_inheritedFlags.textDecorations != other.m_inheritedFlags.textDecorations
872         || m_visualData->textDecoration != other.m_visualData->textDecoration
873         || m_rareNonInheritedData->textDecorationStyle != other.m_rareNonInheritedData->textDecorationStyle
874         || m_rareNonInheritedData->textDecorationColor != other.m_rareNonInheritedData->textDecorationColor
875         || m_rareInheritedData->textDecorationSkip != other.m_rareInheritedData->textDecorationSkip
876         || m_rareInheritedData->textFillColor != other.m_rareInheritedData->textFillColor
877         || m_rareInheritedData->textStrokeColor != other.m_rareInheritedData->textStrokeColor
878         || m_rareInheritedData->textEmphasisColor != other.m_rareInheritedData->textEmphasisColor
879         || m_rareInheritedData->textEmphasisFill != other.m_rareInheritedData->textEmphasisFill)
880         return true;
881
882     return false;
883 }
884
885 bool RenderStyle::changeRequiresRecompositeLayer(const RenderStyle& other, unsigned&) const
886 {
887     if (m_rareNonInheritedData.get() != other.m_rareNonInheritedData.get()) {
888         if (m_rareNonInheritedData->transformStyle3D != other.m_rareNonInheritedData->transformStyle3D
889             || m_rareNonInheritedData->backfaceVisibility != other.m_rareNonInheritedData->backfaceVisibility
890             || m_rareNonInheritedData->perspective != other.m_rareNonInheritedData->perspective
891             || m_rareNonInheritedData->perspectiveOriginX != other.m_rareNonInheritedData->perspectiveOriginX
892             || m_rareNonInheritedData->perspectiveOriginY != other.m_rareNonInheritedData->perspectiveOriginY)
893             return true;
894     }
895
896     return false;
897 }
898
899 StyleDifference RenderStyle::diff(const RenderStyle& other, unsigned& changedContextSensitiveProperties) const
900 {
901     changedContextSensitiveProperties = ContextSensitivePropertyNone;
902
903     StyleDifference svgChange = StyleDifferenceEqual;
904     if (m_svgStyle != other.m_svgStyle) {
905         svgChange = m_svgStyle->diff(other.m_svgStyle.get());
906         if (svgChange == StyleDifferenceLayout)
907             return svgChange;
908     }
909
910     // These properties affect the cached stroke bounding box rects.
911     if (m_rareInheritedData->capStyle != other.m_rareInheritedData->capStyle
912         || m_rareInheritedData->joinStyle != other.m_rareInheritedData->joinStyle
913         || m_rareInheritedData->strokeWidth != other.m_rareInheritedData->strokeWidth)
914         return StyleDifferenceLayout;
915
916     if (changeRequiresLayout(other, changedContextSensitiveProperties))
917         return StyleDifferenceLayout;
918
919     // SVGRenderStyle::diff() might have returned StyleDifferenceRepaint, eg. if fill changes.
920     // If eg. the font-size changed at the same time, we're not allowed to return StyleDifferenceRepaint,
921     // but have to return StyleDifferenceLayout, that's why  this if branch comes after all branches
922     // that are relevant for SVG and might return StyleDifferenceLayout.
923     if (svgChange != StyleDifferenceEqual)
924         return svgChange;
925
926     if (changeRequiresPositionedLayoutOnly(other, changedContextSensitiveProperties))
927         return StyleDifferenceLayoutPositionedMovementOnly;
928
929     if (changeRequiresLayerRepaint(other, changedContextSensitiveProperties))
930         return StyleDifferenceRepaintLayer;
931
932     if (changeRequiresRepaint(other, changedContextSensitiveProperties))
933         return StyleDifferenceRepaint;
934
935     if (changeRequiresRecompositeLayer(other, changedContextSensitiveProperties))
936         return StyleDifferenceRecompositeLayer;
937
938     if (changeRequiresRepaintIfTextOrBorderOrOutline(other, changedContextSensitiveProperties))
939         return StyleDifferenceRepaintIfTextOrBorderOrOutline;
940
941     // Cursors are not checked, since they will be set appropriately in response to mouse events,
942     // so they don't need to cause any repaint or layout.
943
944     // 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
945     // the resulting transition properly.
946     return StyleDifferenceEqual;
947 }
948
949 bool RenderStyle::diffRequiresLayerRepaint(const RenderStyle& style, bool isComposited) const
950 {
951     unsigned changedContextSensitiveProperties = 0;
952
953     if (changeRequiresRepaint(style, changedContextSensitiveProperties))
954         return true;
955
956     if (isComposited && changeRequiresLayerRepaint(style, changedContextSensitiveProperties))
957         return changedContextSensitiveProperties & ContextSensitivePropertyClipRect;
958
959     return false;
960 }
961
962 void RenderStyle::setClip(Length&& top, Length&& right, Length&& bottom, Length&& left)
963 {
964     auto& data = m_visualData.access();
965     data.clip.top() = WTFMove(top);
966     data.clip.right() = WTFMove(right);
967     data.clip.bottom() = WTFMove(bottom);
968     data.clip.left() = WTFMove(left);
969 }
970
971 void RenderStyle::addCursor(RefPtr<StyleImage>&& image, const IntPoint& hotSpot)
972 {
973     auto& cursorData = m_rareInheritedData.access().cursorData;
974     if (!cursorData)
975         cursorData = CursorList::create();
976     cursorData->append(CursorData(WTFMove(image), hotSpot));
977 }
978
979 void RenderStyle::setCursorList(RefPtr<CursorList>&& list)
980 {
981     m_rareInheritedData.access().cursorData = WTFMove(list);
982 }
983
984 void RenderStyle::setQuotes(RefPtr<QuotesData>&& q)
985 {
986     if (m_rareInheritedData->quotes == q || (m_rareInheritedData->quotes && q && *m_rareInheritedData->quotes == *q))
987         return;
988
989     m_rareInheritedData.access().quotes = WTFMove(q);
990 }
991
992 void RenderStyle::setWillChange(RefPtr<WillChangeData>&& willChangeData)
993 {
994     if (arePointingToEqualData(m_rareNonInheritedData->willChange.get(), willChangeData.get()))
995         return;
996
997     m_rareNonInheritedData.access().willChange = WTFMove(willChangeData);
998 }
999
1000 void RenderStyle::clearCursorList()
1001 {
1002     if (m_rareInheritedData->cursorData)
1003         m_rareInheritedData.access().cursorData = nullptr;
1004 }
1005
1006 void RenderStyle::clearContent()
1007 {
1008     if (m_rareNonInheritedData->content)
1009         m_rareNonInheritedData.access().content = nullptr;
1010 }
1011
1012 static inline ContentData& lastContent(ContentData& firstContent)
1013 {
1014     auto* lastContent = &firstContent;
1015     for (auto* content = &firstContent; content; content = content->next())
1016         lastContent = content;
1017     return *lastContent;
1018 }
1019
1020 void RenderStyle::setContent(std::unique_ptr<ContentData> contentData, bool add)
1021 {
1022     auto& data = m_rareNonInheritedData.access();
1023     if (add && data.content)
1024         lastContent(*data.content).setNext(WTFMove(contentData));
1025     else {
1026         data.content = WTFMove(contentData);
1027         auto& altText = data.altText;
1028         if (!altText.isNull())
1029             data.content->setAltText(altText);
1030     }
1031 }
1032
1033 void RenderStyle::setContent(RefPtr<StyleImage>&& image, bool add)
1034 {
1035     if (!image)
1036         return;
1037     setContent(std::make_unique<ImageContentData>(image.releaseNonNull()), add);
1038 }
1039
1040 void RenderStyle::setContent(const String& string, bool add)
1041 {
1042     auto& data = m_rareNonInheritedData.access();
1043     if (add && data.content) {
1044         auto& last = lastContent(*data.content);
1045         if (!is<TextContentData>(last))
1046             last.setNext(std::make_unique<TextContentData>(string));
1047         else {
1048             auto& textContent = downcast<TextContentData>(last);
1049             textContent.setText(textContent.text() + string);
1050         }
1051     } else {
1052         data.content = std::make_unique<TextContentData>(string);
1053         auto& altText = data.altText;
1054         if (!altText.isNull())
1055             data.content->setAltText(altText);
1056     }
1057 }
1058
1059 void RenderStyle::setContent(std::unique_ptr<CounterContent> counter, bool add)
1060 {
1061     if (!counter)
1062         return;
1063     setContent(std::make_unique<CounterContentData>(WTFMove(counter)), add);
1064 }
1065
1066 void RenderStyle::setContent(QuoteType quote, bool add)
1067 {
1068     setContent(std::make_unique<QuoteContentData>(quote), add);
1069 }
1070
1071 void RenderStyle::setContentAltText(const String& string)
1072 {
1073     auto& data = m_rareNonInheritedData.access();
1074     data.altText = string;
1075     if (data.content)
1076         data.content->setAltText(string);
1077 }
1078
1079 const String& RenderStyle::contentAltText() const
1080 {
1081     return m_rareNonInheritedData->altText;
1082 }
1083
1084 void RenderStyle::setHasAttrContent()
1085 {
1086     setUnique();
1087     SET_VAR(m_rareNonInheritedData, hasAttrContent, true);
1088 }
1089
1090 static inline bool requireTransformOrigin(const Vector<RefPtr<TransformOperation>>& transformOperations, RenderStyle::ApplyTransformOrigin applyOrigin)
1091 {
1092     // The transform-origin property brackets the transform with translate operations.
1093     // When the only transform is a translation, the transform-origin is irrelevant.
1094
1095     if (applyOrigin != RenderStyle::IncludeTransformOrigin)
1096         return false;
1097
1098     for (auto& operation : transformOperations) {
1099         // FIXME: Use affectedByTransformOrigin().
1100         auto type = operation->type();
1101         if (type != TransformOperation::TRANSLATE
1102             && type != TransformOperation::TRANSLATE_3D
1103             && type != TransformOperation::TRANSLATE_X
1104             && type != TransformOperation::TRANSLATE_Y
1105             && type != TransformOperation::TRANSLATE_Z)
1106             return true;
1107     }
1108
1109     return false;
1110 }
1111
1112 void RenderStyle::applyTransform(TransformationMatrix& transform, const FloatRect& boundingBox, ApplyTransformOrigin applyOrigin) const
1113 {
1114     auto& operations = m_rareNonInheritedData->transform->operations.operations();
1115     bool applyTransformOrigin = requireTransformOrigin(operations, applyOrigin);
1116
1117     float offsetX = transformOriginX().isPercent() ? boundingBox.x() : 0;
1118     float offsetY = transformOriginY().isPercent() ? boundingBox.y() : 0;
1119
1120     if (applyTransformOrigin) {
1121         transform.translate3d(floatValueForLength(transformOriginX(), boundingBox.width()) + offsetX,
1122                               floatValueForLength(transformOriginY(), boundingBox.height()) + offsetY,
1123                               transformOriginZ());
1124     }
1125
1126     for (auto& operation : operations)
1127         operation->apply(transform, boundingBox.size());
1128
1129     if (applyTransformOrigin) {
1130         transform.translate3d(-floatValueForLength(transformOriginX(), boundingBox.width()) - offsetX,
1131                               -floatValueForLength(transformOriginY(), boundingBox.height()) - offsetY,
1132                               -transformOriginZ());
1133     }
1134 }
1135
1136 void RenderStyle::setPageScaleTransform(float scale)
1137 {
1138     if (scale == 1)
1139         return;
1140     TransformOperations transform;
1141     transform.operations().append(ScaleTransformOperation::create(scale, scale, ScaleTransformOperation::SCALE));
1142     setTransform(transform);
1143     setTransformOriginX(Length(0, Fixed));
1144     setTransformOriginY(Length(0, Fixed));
1145 }
1146
1147 void RenderStyle::setTextShadow(std::unique_ptr<ShadowData> shadowData, bool add)
1148 {
1149     ASSERT(!shadowData || (!shadowData->spread() && shadowData->style() == Normal));
1150
1151     auto& rareData = m_rareInheritedData.access();
1152     if (!add) {
1153         rareData.textShadow = WTFMove(shadowData);
1154         return;
1155     }
1156
1157     shadowData->setNext(WTFMove(rareData.textShadow));
1158     rareData.textShadow = WTFMove(shadowData);
1159 }
1160
1161 void RenderStyle::setBoxShadow(std::unique_ptr<ShadowData> shadowData, bool add)
1162 {
1163     auto& rareData = m_rareNonInheritedData.access();
1164     if (!add) {
1165         rareData.boxShadow = WTFMove(shadowData);
1166         return;
1167     }
1168
1169     shadowData->setNext(WTFMove(rareData.boxShadow));
1170     rareData.boxShadow = WTFMove(shadowData);
1171 }
1172
1173 static RoundedRect::Radii calcRadiiFor(const BorderData& border, const LayoutSize& size)
1174 {
1175     return {
1176         sizeForLengthSize(border.topLeft(), size),
1177         sizeForLengthSize(border.topRight(), size),
1178         sizeForLengthSize(border.bottomLeft(), size),
1179         sizeForLengthSize(border.bottomRight(), size)
1180     };
1181 }
1182
1183 StyleImage* RenderStyle::listStyleImage() const { return m_rareInheritedData->listStyleImage.get(); }
1184
1185 void RenderStyle::setListStyleImage(RefPtr<StyleImage>&& v)
1186 {
1187     if (m_rareInheritedData->listStyleImage != v)
1188         m_rareInheritedData.access().listStyleImage = WTFMove(v);
1189 }
1190
1191 const Color& RenderStyle::color() const
1192 {
1193     return m_inheritedData->color;
1194 }
1195
1196 const Color& RenderStyle::visitedLinkColor() const
1197 {
1198     return m_inheritedData->visitedLinkColor;
1199 }
1200
1201 void RenderStyle::setColor(const Color& v)
1202 {
1203     SET_VAR(m_inheritedData, color, v);
1204 }
1205
1206 void RenderStyle::setVisitedLinkColor(const Color& v)
1207 {
1208     SET_VAR(m_inheritedData, visitedLinkColor, v);
1209 }
1210
1211 float RenderStyle::horizontalBorderSpacing() const
1212 {
1213     return m_inheritedData->horizontalBorderSpacing;
1214 }
1215
1216 float RenderStyle::verticalBorderSpacing() const
1217 {
1218     return m_inheritedData->verticalBorderSpacing;
1219 }
1220
1221 void RenderStyle::setHorizontalBorderSpacing(float v)
1222 {
1223     SET_VAR(m_inheritedData, horizontalBorderSpacing, v);
1224 }
1225
1226 void RenderStyle::setVerticalBorderSpacing(float v)
1227 {
1228     SET_VAR(m_inheritedData, verticalBorderSpacing, v);
1229 }
1230
1231 RoundedRect RenderStyle::getRoundedBorderFor(const LayoutRect& borderRect, bool includeLogicalLeftEdge, bool includeLogicalRightEdge) const
1232 {
1233     RoundedRect roundedRect(borderRect);
1234     if (hasBorderRadius()) {
1235         RoundedRect::Radii radii = calcRadiiFor(m_surroundData->border, borderRect.size());
1236         radii.scale(calcBorderRadiiConstraintScaleFor(borderRect, radii));
1237         roundedRect.includeLogicalEdges(radii, isHorizontalWritingMode(), includeLogicalLeftEdge, includeLogicalRightEdge);
1238     }
1239     return roundedRect;
1240 }
1241
1242 RoundedRect RenderStyle::getRoundedInnerBorderFor(const LayoutRect& borderRect, bool includeLogicalLeftEdge, bool includeLogicalRightEdge) const
1243 {
1244     bool horizontal = isHorizontalWritingMode();
1245     auto leftWidth = (!horizontal || includeLogicalLeftEdge) ? borderLeftWidth() : 0;
1246     auto rightWidth = (!horizontal || includeLogicalRightEdge) ? borderRightWidth() : 0;
1247     auto topWidth = (horizontal || includeLogicalLeftEdge) ? borderTopWidth() : 0;
1248     auto bottomWidth = (horizontal || includeLogicalRightEdge) ? borderBottomWidth() : 0;
1249     return getRoundedInnerBorderFor(borderRect, topWidth, bottomWidth, leftWidth, rightWidth, includeLogicalLeftEdge, includeLogicalRightEdge);
1250 }
1251
1252 RoundedRect RenderStyle::getRoundedInnerBorderFor(const LayoutRect& borderRect, LayoutUnit topWidth, LayoutUnit bottomWidth,
1253     LayoutUnit leftWidth, LayoutUnit rightWidth, bool includeLogicalLeftEdge, bool includeLogicalRightEdge) const
1254 {
1255     RoundedRect roundedRect { { borderRect.x() + leftWidth, borderRect.y() + topWidth,
1256         borderRect.width() - leftWidth - rightWidth, borderRect.height() - topWidth - bottomWidth } };
1257     if (hasBorderRadius()) {
1258         auto radii = getRoundedBorderFor(borderRect).radii();
1259         radii.shrink(topWidth, bottomWidth, leftWidth, rightWidth);
1260         roundedRect.includeLogicalEdges(radii, isHorizontalWritingMode(), includeLogicalLeftEdge, includeLogicalRightEdge);
1261     }
1262     return roundedRect;
1263 }
1264
1265 static bool allLayersAreFixed(const FillLayer& layers)
1266 {
1267     for (auto* layer = &layers; layer; layer = layer->next()) {
1268         if (!(layer->image() && layer->attachment() == FixedBackgroundAttachment))
1269             return false;
1270     }
1271     return true;
1272 }
1273
1274 bool RenderStyle::hasEntirelyFixedBackground() const
1275 {
1276     return allLayersAreFixed(backgroundLayers());
1277 }
1278
1279 const CounterDirectiveMap* RenderStyle::counterDirectives() const
1280 {
1281     return m_rareNonInheritedData->counterDirectives.get();
1282 }
1283
1284 CounterDirectiveMap& RenderStyle::accessCounterDirectives()
1285 {
1286     auto& map = m_rareNonInheritedData.access().counterDirectives;
1287     if (!map)
1288         map = std::make_unique<CounterDirectiveMap>();
1289     return *map;
1290 }
1291
1292 const CounterDirectives RenderStyle::getCounterDirectives(const AtomicString& identifier) const
1293 {
1294     if (const CounterDirectiveMap* directives = counterDirectives())
1295         return directives->get(identifier);
1296     return CounterDirectives();
1297 }
1298
1299 const AtomicString& RenderStyle::hyphenString() const
1300 {
1301     ASSERT(hyphens() != HyphensNone);
1302
1303     auto& hyphenationString = m_rareInheritedData->hyphenationString;
1304     if (!hyphenationString.isNull())
1305         return hyphenationString;
1306
1307     // FIXME: This should depend on locale.
1308     static NeverDestroyed<AtomicString> hyphenMinusString(&hyphenMinus, 1);
1309     static NeverDestroyed<AtomicString> hyphenString(&hyphen, 1);
1310     return fontCascade().primaryFont().glyphForCharacter(hyphen) ? hyphenString : hyphenMinusString;
1311 }
1312
1313 const AtomicString& RenderStyle::textEmphasisMarkString() const
1314 {
1315     switch (textEmphasisMark()) {
1316     case TextEmphasisMarkNone:
1317         return nullAtom;
1318     case TextEmphasisMarkCustom:
1319         return textEmphasisCustomMark();
1320     case TextEmphasisMarkDot: {
1321         static NeverDestroyed<AtomicString> filledDotString(&bullet, 1);
1322         static NeverDestroyed<AtomicString> openDotString(&whiteBullet, 1);
1323         return textEmphasisFill() == TextEmphasisFillFilled ? filledDotString : openDotString;
1324     }
1325     case TextEmphasisMarkCircle: {
1326         static NeverDestroyed<AtomicString> filledCircleString(&blackCircle, 1);
1327         static NeverDestroyed<AtomicString> openCircleString(&whiteCircle, 1);
1328         return textEmphasisFill() == TextEmphasisFillFilled ? filledCircleString : openCircleString;
1329     }
1330     case TextEmphasisMarkDoubleCircle: {
1331         static NeverDestroyed<AtomicString> filledDoubleCircleString(&fisheye, 1);
1332         static NeverDestroyed<AtomicString> openDoubleCircleString(&bullseye, 1);
1333         return textEmphasisFill() == TextEmphasisFillFilled ? filledDoubleCircleString : openDoubleCircleString;
1334     }
1335     case TextEmphasisMarkTriangle: {
1336         static NeverDestroyed<AtomicString> filledTriangleString(&blackUpPointingTriangle, 1);
1337         static NeverDestroyed<AtomicString> openTriangleString(&whiteUpPointingTriangle, 1);
1338         return textEmphasisFill() == TextEmphasisFillFilled ? filledTriangleString : openTriangleString;
1339     }
1340     case TextEmphasisMarkSesame: {
1341         static NeverDestroyed<AtomicString> filledSesameString(&sesameDot, 1);
1342         static NeverDestroyed<AtomicString> openSesameString(&whiteSesameDot, 1);
1343         return textEmphasisFill() == TextEmphasisFillFilled ? filledSesameString : openSesameString;
1344     }
1345     case TextEmphasisMarkAuto:
1346         ASSERT_NOT_REACHED();
1347         return nullAtom;
1348     }
1349
1350     ASSERT_NOT_REACHED();
1351     return nullAtom;
1352 }
1353
1354 #if ENABLE(DASHBOARD_SUPPORT)
1355
1356 const Vector<StyleDashboardRegion>& RenderStyle::initialDashboardRegions()
1357 {
1358     static NeverDestroyed<Vector<StyleDashboardRegion>> emptyList;
1359     return emptyList;
1360 }
1361
1362 const Vector<StyleDashboardRegion>& RenderStyle::noneDashboardRegions()
1363 {
1364     static NeverDestroyed<Vector<StyleDashboardRegion>> noneList;
1365     static bool noneListInitialized = false;
1366     if (!noneListInitialized) {
1367         noneList.get().append(StyleDashboardRegion { emptyString(), { }, StyleDashboardRegion::None });
1368         noneListInitialized = true;
1369     }
1370     return noneList;
1371 }
1372
1373 #endif
1374
1375 void RenderStyle::adjustAnimations()
1376 {
1377     auto* animationList = m_rareNonInheritedData->animations.get();
1378     if (!animationList)
1379         return;
1380
1381     // Get rid of empty animations and anything beyond them
1382     for (size_t i = 0, size = animationList->size(); i < size; ++i) {
1383         if (animationList->animation(i).isEmpty()) {
1384             animationList->resize(i);
1385             break;
1386         }
1387     }
1388
1389     if (animationList->isEmpty()) {
1390         clearAnimations();
1391         return;
1392     }
1393
1394     // Repeat patterns into layers that don't have some properties set.
1395     animationList->fillUnsetProperties();
1396 }
1397
1398 void RenderStyle::adjustTransitions()
1399 {
1400     auto* transitionList = m_rareNonInheritedData->transitions.get();
1401     if (!transitionList)
1402         return;
1403
1404     // Get rid of empty transitions and anything beyond them
1405     for (size_t i = 0, size = transitionList->size(); i < size; ++i) {
1406         if (transitionList->animation(i).isEmpty()) {
1407             transitionList->resize(i);
1408             break;
1409         }
1410     }
1411
1412     if (transitionList->isEmpty()) {
1413         clearTransitions();
1414         return;
1415     }
1416
1417     // Repeat patterns into layers that don't have some properties set.
1418     transitionList->fillUnsetProperties();
1419
1420     // Make sure there are no duplicate properties.
1421     // This is an O(n^2) algorithm but the lists tend to be short, so it is probably OK.
1422     for (size_t i = 0; i < transitionList->size(); ++i) {
1423         for (size_t j = i + 1; j < transitionList->size(); ++j) {
1424             if (transitionList->animation(i).property() == transitionList->animation(j).property()) {
1425                 // toss i
1426                 transitionList->remove(i);
1427                 j = i;
1428             }
1429         }
1430     }
1431 }
1432
1433 AnimationList& RenderStyle::ensureAnimations()
1434 {
1435     if (!m_rareNonInheritedData.access().animations)
1436         m_rareNonInheritedData.access().animations = std::make_unique<AnimationList>();
1437     return *m_rareNonInheritedData->animations;
1438 }
1439
1440 AnimationList& RenderStyle::ensureTransitions()
1441 {
1442     if (!m_rareNonInheritedData.access().transitions)
1443         m_rareNonInheritedData.access().transitions = std::make_unique<AnimationList>();
1444     return *m_rareNonInheritedData->transitions;
1445 }
1446
1447 const Animation* RenderStyle::transitionForProperty(CSSPropertyID property) const
1448 {
1449     auto* transitions = this->transitions();
1450     if (!transitions)
1451         return nullptr;
1452     for (size_t i = 0, size = transitions->size(); i < size; ++i) {
1453         auto& animation = transitions->animation(i);
1454         if (animation.animationMode() == Animation::AnimateAll || animation.property() == property)
1455             return &animation;
1456     }
1457     return nullptr;
1458 }
1459
1460 const FontCascade& RenderStyle::fontCascade() const
1461 {
1462     return m_inheritedData->fontCascade;
1463 }
1464
1465 const FontMetrics& RenderStyle::fontMetrics() const
1466 {
1467     return m_inheritedData->fontCascade.fontMetrics();
1468 }
1469
1470 const FontCascadeDescription& RenderStyle::fontDescription() const
1471 {
1472     return m_inheritedData->fontCascade.fontDescription();
1473 }
1474
1475 float RenderStyle::specifiedFontSize() const
1476 {
1477     return fontDescription().specifiedSize();
1478 }
1479
1480 float RenderStyle::computedFontSize() const
1481 {
1482     return fontDescription().computedSize();
1483 }
1484
1485 int RenderStyle::fontSize() const
1486 {
1487     return m_inheritedData->fontCascade.pixelSize();
1488 }
1489
1490 const Length& RenderStyle::wordSpacing() const
1491 {
1492     return m_rareInheritedData->wordSpacing;
1493 }
1494
1495 float RenderStyle::letterSpacing() const
1496 {
1497     return m_inheritedData->fontCascade.letterSpacing();
1498 }
1499
1500 bool RenderStyle::setFontDescription(const FontCascadeDescription& description)
1501 {
1502     if (m_inheritedData->fontCascade.fontDescription() == description)
1503         return false;
1504     auto& cascade = m_inheritedData.access().fontCascade;
1505     cascade = { description, cascade.letterSpacing(), cascade.wordSpacing() };
1506     return true;
1507 }
1508
1509 const Length& RenderStyle::specifiedLineHeight() const
1510 {
1511 #if ENABLE(TEXT_AUTOSIZING)
1512     return m_inheritedData->specifiedLineHeight;
1513 #else
1514     return m_inheritedData->lineHeight;
1515 #endif
1516 }
1517
1518 #if ENABLE(TEXT_AUTOSIZING)
1519
1520 void RenderStyle::setSpecifiedLineHeight(Length&& height)
1521 {
1522     SET_VAR(m_inheritedData, specifiedLineHeight, WTFMove(height));
1523 }
1524
1525 #endif
1526
1527 const Length& RenderStyle::lineHeight() const
1528 {
1529     return m_inheritedData->lineHeight;
1530 }
1531
1532 void RenderStyle::setLineHeight(Length&& height)
1533 {
1534     SET_VAR(m_inheritedData, lineHeight, WTFMove(height));
1535 }
1536
1537 int RenderStyle::computedLineHeight() const
1538 {
1539     const Length& lh = lineHeight();
1540
1541     // Negative value means the line height is not set. Use the font's built-in spacing.
1542     if (lh.isNegative())
1543         return fontMetrics().lineSpacing();
1544
1545     if (lh.isPercentOrCalculated())
1546         return minimumValueForLength(lh, fontSize());
1547
1548     return clampTo<int>(lh.value());
1549 }
1550
1551 void RenderStyle::setWordSpacing(Length&& value)
1552 {
1553     float fontWordSpacing;
1554     switch (value.type()) {
1555     case Auto:
1556         fontWordSpacing = 0;
1557         break;
1558     case Percent:
1559         fontWordSpacing = value.percent() * fontCascade().spaceWidth() / 100;
1560         break;
1561     case Fixed:
1562         fontWordSpacing = value.value();
1563         break;
1564     case Calculated:
1565         fontWordSpacing = value.nonNanCalculatedValue(maxValueForCssLength);
1566         break;
1567     default:
1568         ASSERT_NOT_REACHED();
1569         fontWordSpacing = 0;
1570         break;
1571     }
1572     m_inheritedData.access().fontCascade.setWordSpacing(fontWordSpacing);
1573     m_rareInheritedData.access().wordSpacing = WTFMove(value);
1574 }
1575
1576 void RenderStyle::setLetterSpacing(float v) { m_inheritedData.access().fontCascade.setLetterSpacing(v); }
1577
1578 void RenderStyle::setFontSize(float size)
1579 {
1580     // size must be specifiedSize if Text Autosizing is enabled, but computedSize if text
1581     // zoom is enabled (if neither is enabled it's irrelevant as they're probably the same).
1582
1583     ASSERT(std::isfinite(size));
1584     if (!std::isfinite(size) || size < 0)
1585         size = 0;
1586     else
1587         size = std::min(maximumAllowedFontSize, size);
1588
1589     FontSelector* currentFontSelector = fontCascade().fontSelector();
1590     auto description = fontDescription();
1591     description.setSpecifiedSize(size);
1592     description.setComputedSize(size);
1593
1594     setFontDescription(description);
1595     fontCascade().update(currentFontSelector);
1596 }
1597
1598 #if ENABLE(VARIATION_FONTS)
1599 void RenderStyle::setFontVariationSettings(FontVariationSettings settings)
1600 {
1601     FontSelector* currentFontSelector = fontCascade().fontSelector();
1602     auto description = fontDescription();
1603     description.setVariationSettings(WTFMove(settings));
1604
1605     setFontDescription(description);
1606     fontCascade().update(currentFontSelector);
1607 }
1608 #endif
1609
1610 void RenderStyle::getShadowExtent(const ShadowData* shadow, LayoutUnit& top, LayoutUnit& right, LayoutUnit& bottom, LayoutUnit& left) const
1611 {
1612     top = 0;
1613     right = 0;
1614     bottom = 0;
1615     left = 0;
1616
1617     for ( ; shadow; shadow = shadow->next()) {
1618         if (shadow->style() == Inset)
1619             continue;
1620
1621         int extentAndSpread = shadow->paintingExtent() + shadow->spread();
1622         top = std::min<LayoutUnit>(top, shadow->y() - extentAndSpread);
1623         right = std::max<LayoutUnit>(right, shadow->x() + extentAndSpread);
1624         bottom = std::max<LayoutUnit>(bottom, shadow->y() + extentAndSpread);
1625         left = std::min<LayoutUnit>(left, shadow->x() - extentAndSpread);
1626     }
1627 }
1628
1629 LayoutBoxExtent RenderStyle::getShadowInsetExtent(const ShadowData* shadow) const
1630 {
1631     LayoutUnit top = 0;
1632     LayoutUnit right = 0;
1633     LayoutUnit bottom = 0;
1634     LayoutUnit left = 0;
1635
1636     for ( ; shadow; shadow = shadow->next()) {
1637         if (shadow->style() == Normal)
1638             continue;
1639
1640         int extentAndSpread = shadow->paintingExtent() + shadow->spread();
1641         top = std::max<LayoutUnit>(top, shadow->y() + extentAndSpread);
1642         right = std::min<LayoutUnit>(right, shadow->x() - extentAndSpread);
1643         bottom = std::min<LayoutUnit>(bottom, shadow->y() - extentAndSpread);
1644         left = std::max<LayoutUnit>(left, shadow->x() + extentAndSpread);
1645     }
1646
1647     return LayoutBoxExtent(top, right, bottom, left);
1648 }
1649
1650 void RenderStyle::getShadowHorizontalExtent(const ShadowData* shadow, LayoutUnit &left, LayoutUnit &right) const
1651 {
1652     left = 0;
1653     right = 0;
1654
1655     for ( ; shadow; shadow = shadow->next()) {
1656         if (shadow->style() == Inset)
1657             continue;
1658
1659         int extentAndSpread = shadow->paintingExtent() + shadow->spread();
1660         left = std::min<LayoutUnit>(left, shadow->x() - extentAndSpread);
1661         right = std::max<LayoutUnit>(right, shadow->x() + extentAndSpread);
1662     }
1663 }
1664
1665 void RenderStyle::getShadowVerticalExtent(const ShadowData* shadow, LayoutUnit &top, LayoutUnit &bottom) const
1666 {
1667     top = 0;
1668     bottom = 0;
1669
1670     for ( ; shadow; shadow = shadow->next()) {
1671         if (shadow->style() == Inset)
1672             continue;
1673
1674         int extentAndSpread = shadow->paintingExtent() + shadow->spread();
1675         top = std::min<LayoutUnit>(top, shadow->y() - extentAndSpread);
1676         bottom = std::max<LayoutUnit>(bottom, shadow->y() + extentAndSpread);
1677     }
1678 }
1679
1680 Color RenderStyle::colorIncludingFallback(int colorProperty, bool visitedLink) const
1681 {
1682     Color result;
1683     EBorderStyle borderStyle = BNONE;
1684     switch (colorProperty) {
1685     case CSSPropertyBackgroundColor:
1686         return visitedLink ? visitedLinkBackgroundColor() : backgroundColor(); // Background color doesn't fall back.
1687     case CSSPropertyBorderLeftColor:
1688         result = visitedLink ? visitedLinkBorderLeftColor() : borderLeftColor();
1689         borderStyle = borderLeftStyle();
1690         break;
1691     case CSSPropertyBorderRightColor:
1692         result = visitedLink ? visitedLinkBorderRightColor() : borderRightColor();
1693         borderStyle = borderRightStyle();
1694         break;
1695     case CSSPropertyBorderTopColor:
1696         result = visitedLink ? visitedLinkBorderTopColor() : borderTopColor();
1697         borderStyle = borderTopStyle();
1698         break;
1699     case CSSPropertyBorderBottomColor:
1700         result = visitedLink ? visitedLinkBorderBottomColor() : borderBottomColor();
1701         borderStyle = borderBottomStyle();
1702         break;
1703     case CSSPropertyColor:
1704         result = visitedLink ? visitedLinkColor() : color();
1705         break;
1706     case CSSPropertyOutlineColor:
1707         result = visitedLink ? visitedLinkOutlineColor() : outlineColor();
1708         break;
1709     case CSSPropertyColumnRuleColor:
1710         result = visitedLink ? visitedLinkColumnRuleColor() : columnRuleColor();
1711         break;
1712     case CSSPropertyWebkitTextDecorationColor:
1713         // Text decoration color fallback is handled in RenderObject::decorationColor.
1714         return visitedLink ? visitedLinkTextDecorationColor() : textDecorationColor();
1715     case CSSPropertyWebkitTextEmphasisColor:
1716         result = visitedLink ? visitedLinkTextEmphasisColor() : textEmphasisColor();
1717         break;
1718     case CSSPropertyWebkitTextFillColor:
1719         result = visitedLink ? visitedLinkTextFillColor() : textFillColor();
1720         break;
1721     case CSSPropertyWebkitTextStrokeColor:
1722         result = visitedLink ? visitedLinkTextStrokeColor() : textStrokeColor();
1723         break;
1724     default:
1725         ASSERT_NOT_REACHED();
1726         break;
1727     }
1728
1729     if (!result.isValid()) {
1730         if (!visitedLink && (borderStyle == INSET || borderStyle == OUTSET || borderStyle == RIDGE || borderStyle == GROOVE))
1731             result = Color(238, 238, 238);
1732         else
1733             result = visitedLink ? visitedLinkColor() : color();
1734     }
1735     return result;
1736 }
1737
1738 Color RenderStyle::visitedDependentColor(int colorProperty) const
1739 {
1740     Color unvisitedColor = colorIncludingFallback(colorProperty, false);
1741     if (insideLink() != InsideVisitedLink)
1742         return unvisitedColor;
1743
1744     Color visitedColor = colorIncludingFallback(colorProperty, true);
1745
1746     // Text decoration color validity is preserved (checked in RenderObject::decorationColor).
1747     if (colorProperty == CSSPropertyWebkitTextDecorationColor)
1748         return visitedColor;
1749
1750     // FIXME: Technically someone could explicitly specify the color transparent, but for now we'll just
1751     // assume that if the background color is transparent that it wasn't set. Note that it's weird that
1752     // we're returning unvisited info for a visited link, but given our restriction that the alpha values
1753     // have to match, it makes more sense to return the unvisited background color if specified than it
1754     // does to return black. This behavior matches what Firefox 4 does as well.
1755     if (colorProperty == CSSPropertyBackgroundColor && visitedColor == Color::transparent)
1756         return unvisitedColor;
1757
1758     // Take the alpha from the unvisited color, but get the RGB values from the visited color.
1759     return visitedColor.colorWithAlpha(unvisitedColor.alphaAsFloat());
1760 }
1761
1762 const BorderValue& RenderStyle::borderBefore() const
1763 {
1764     switch (writingMode()) {
1765     case TopToBottomWritingMode:
1766         return borderTop();
1767     case BottomToTopWritingMode:
1768         return borderBottom();
1769     case LeftToRightWritingMode:
1770         return borderLeft();
1771     case RightToLeftWritingMode:
1772         return borderRight();
1773     }
1774     ASSERT_NOT_REACHED();
1775     return borderTop();
1776 }
1777
1778 const BorderValue& RenderStyle::borderAfter() const
1779 {
1780     switch (writingMode()) {
1781     case TopToBottomWritingMode:
1782         return borderBottom();
1783     case BottomToTopWritingMode:
1784         return borderTop();
1785     case LeftToRightWritingMode:
1786         return borderRight();
1787     case RightToLeftWritingMode:
1788         return borderLeft();
1789     }
1790     ASSERT_NOT_REACHED();
1791     return borderBottom();
1792 }
1793
1794 const BorderValue& RenderStyle::borderStart() const
1795 {
1796     if (isHorizontalWritingMode())
1797         return isLeftToRightDirection() ? borderLeft() : borderRight();
1798     return isLeftToRightDirection() ? borderTop() : borderBottom();
1799 }
1800
1801 const BorderValue& RenderStyle::borderEnd() const
1802 {
1803     if (isHorizontalWritingMode())
1804         return isLeftToRightDirection() ? borderRight() : borderLeft();
1805     return isLeftToRightDirection() ? borderBottom() : borderTop();
1806 }
1807
1808 float RenderStyle::borderBeforeWidth() const
1809 {
1810     switch (writingMode()) {
1811     case TopToBottomWritingMode:
1812         return borderTopWidth();
1813     case BottomToTopWritingMode:
1814         return borderBottomWidth();
1815     case LeftToRightWritingMode:
1816         return borderLeftWidth();
1817     case RightToLeftWritingMode:
1818         return borderRightWidth();
1819     }
1820     ASSERT_NOT_REACHED();
1821     return borderTopWidth();
1822 }
1823
1824 float RenderStyle::borderAfterWidth() const
1825 {
1826     switch (writingMode()) {
1827     case TopToBottomWritingMode:
1828         return borderBottomWidth();
1829     case BottomToTopWritingMode:
1830         return borderTopWidth();
1831     case LeftToRightWritingMode:
1832         return borderRightWidth();
1833     case RightToLeftWritingMode:
1834         return borderLeftWidth();
1835     }
1836     ASSERT_NOT_REACHED();
1837     return borderBottomWidth();
1838 }
1839
1840 float RenderStyle::borderStartWidth() const
1841 {
1842     if (isHorizontalWritingMode())
1843         return isLeftToRightDirection() ? borderLeftWidth() : borderRightWidth();
1844     return isLeftToRightDirection() ? borderTopWidth() : borderBottomWidth();
1845 }
1846
1847 float RenderStyle::borderEndWidth() const
1848 {
1849     if (isHorizontalWritingMode())
1850         return isLeftToRightDirection() ? borderRightWidth() : borderLeftWidth();
1851     return isLeftToRightDirection() ? borderBottomWidth() : borderTopWidth();
1852 }
1853
1854 void RenderStyle::setMarginStart(Length&& margin)
1855 {
1856     if (isHorizontalWritingMode()) {
1857         if (isLeftToRightDirection())
1858             setMarginLeft(WTFMove(margin));
1859         else
1860             setMarginRight(WTFMove(margin));
1861     } else {
1862         if (isLeftToRightDirection())
1863             setMarginTop(WTFMove(margin));
1864         else
1865             setMarginBottom(WTFMove(margin));
1866     }
1867 }
1868
1869 void RenderStyle::setMarginEnd(Length&& margin)
1870 {
1871     if (isHorizontalWritingMode()) {
1872         if (isLeftToRightDirection())
1873             setMarginRight(WTFMove(margin));
1874         else
1875             setMarginLeft(WTFMove(margin));
1876     } else {
1877         if (isLeftToRightDirection())
1878             setMarginBottom(WTFMove(margin));
1879         else
1880             setMarginTop(WTFMove(margin));
1881     }
1882 }
1883
1884 TextEmphasisMark RenderStyle::textEmphasisMark() const
1885 {
1886     auto mark = static_cast<TextEmphasisMark>(m_rareInheritedData->textEmphasisMark);
1887     if (mark != TextEmphasisMarkAuto)
1888         return mark;
1889     if (isHorizontalWritingMode())
1890         return TextEmphasisMarkDot;
1891     return TextEmphasisMarkSesame;
1892 }
1893
1894 #if ENABLE(TOUCH_EVENTS)
1895
1896 Color RenderStyle::initialTapHighlightColor()
1897 {
1898     return RenderTheme::tapHighlightColor();
1899 }
1900
1901 #endif
1902
1903 LayoutBoxExtent RenderStyle::imageOutsets(const NinePieceImage& image) const
1904 {
1905     return LayoutBoxExtent(NinePieceImage::computeOutset(image.outset().top(), borderTopWidth()),
1906                            NinePieceImage::computeOutset(image.outset().right(), borderRightWidth()),
1907                            NinePieceImage::computeOutset(image.outset().bottom(), borderBottomWidth()),
1908                            NinePieceImage::computeOutset(image.outset().left(), borderLeftWidth()));
1909 }
1910
1911 std::pair<FontOrientation, NonCJKGlyphOrientation> RenderStyle::fontAndGlyphOrientation()
1912 {
1913     // FIXME: TextOrientationSideways should map to sideways-left in vertical-lr, which is not supported yet.
1914
1915     if (isHorizontalWritingMode())
1916         return { Horizontal, NonCJKGlyphOrientation::Mixed };
1917
1918     switch (textOrientation()) {
1919     case TextOrientation::Mixed:
1920         return { Vertical, NonCJKGlyphOrientation::Mixed };
1921     case TextOrientation::Upright:
1922         return { Vertical, NonCJKGlyphOrientation::Upright };
1923     case TextOrientation::Sideways:
1924         return { Horizontal, NonCJKGlyphOrientation::Mixed };
1925     default:
1926         ASSERT_NOT_REACHED();
1927         return { Horizontal, NonCJKGlyphOrientation::Mixed };
1928     }
1929 }
1930
1931 void RenderStyle::setBorderImageSource(RefPtr<StyleImage>&& image)
1932 {
1933     if (m_surroundData->border.m_image.image() == image.get())
1934         return;
1935     m_surroundData.access().border.m_image.setImage(WTFMove(image));
1936 }
1937
1938 void RenderStyle::setBorderImageSlices(LengthBox&& slices)
1939 {
1940     if (m_surroundData->border.m_image.imageSlices() == slices)
1941         return;
1942     m_surroundData.access().border.m_image.setImageSlices(WTFMove(slices));
1943 }
1944
1945 void RenderStyle::setBorderImageWidth(LengthBox&& slices)
1946 {
1947     if (m_surroundData->border.m_image.borderSlices() == slices)
1948         return;
1949     m_surroundData.access().border.m_image.setBorderSlices(WTFMove(slices));
1950 }
1951
1952 void RenderStyle::setBorderImageOutset(LengthBox&& outset)
1953 {
1954     if (m_surroundData->border.m_image.outset() == outset)
1955         return;
1956     m_surroundData.access().border.m_image.setOutset(WTFMove(outset));
1957 }
1958
1959 void RenderStyle::setColumnStylesFromPaginationMode(const Pagination::Mode& paginationMode)
1960 {
1961     if (paginationMode == Pagination::Unpaginated)
1962         return;
1963     
1964     setColumnFill(ColumnFillAuto);
1965     
1966     switch (paginationMode) {
1967     case Pagination::LeftToRightPaginated:
1968         setColumnAxis(HorizontalColumnAxis);
1969         if (isHorizontalWritingMode())
1970             setColumnProgression(isLeftToRightDirection() ? NormalColumnProgression : ReverseColumnProgression);
1971         else
1972             setColumnProgression(isFlippedBlocksWritingMode() ? ReverseColumnProgression : NormalColumnProgression);
1973         break;
1974     case Pagination::RightToLeftPaginated:
1975         setColumnAxis(HorizontalColumnAxis);
1976         if (isHorizontalWritingMode())
1977             setColumnProgression(isLeftToRightDirection() ? ReverseColumnProgression : NormalColumnProgression);
1978         else
1979             setColumnProgression(isFlippedBlocksWritingMode() ? NormalColumnProgression : ReverseColumnProgression);
1980         break;
1981     case Pagination::TopToBottomPaginated:
1982         setColumnAxis(VerticalColumnAxis);
1983         if (isHorizontalWritingMode())
1984             setColumnProgression(isFlippedBlocksWritingMode() ? ReverseColumnProgression : NormalColumnProgression);
1985         else
1986             setColumnProgression(isLeftToRightDirection() ? NormalColumnProgression : ReverseColumnProgression);
1987         break;
1988     case Pagination::BottomToTopPaginated:
1989         setColumnAxis(VerticalColumnAxis);
1990         if (isHorizontalWritingMode())
1991             setColumnProgression(isFlippedBlocksWritingMode() ? NormalColumnProgression : ReverseColumnProgression);
1992         else
1993             setColumnProgression(isLeftToRightDirection() ? ReverseColumnProgression : NormalColumnProgression);
1994         break;
1995     case Pagination::Unpaginated:
1996         ASSERT_NOT_REACHED();
1997         break;
1998     }
1999 }
2000
2001 #if ENABLE(CSS_SCROLL_SNAP)
2002
2003 ScrollSnapType RenderStyle::initialScrollSnapType()
2004 {
2005     return { };
2006 }
2007
2008 ScrollSnapAlign RenderStyle::initialScrollSnapAlign()
2009 {
2010     return { };
2011 }
2012
2013 const StyleScrollSnapArea& RenderStyle::scrollSnapArea() const
2014 {
2015     return *m_rareNonInheritedData->scrollSnapArea;
2016 }
2017
2018 const StyleScrollSnapPort& RenderStyle::scrollSnapPort() const
2019 {
2020     return *m_rareNonInheritedData->scrollSnapPort;
2021 }
2022
2023 const ScrollSnapType& RenderStyle::scrollSnapType() const
2024 {
2025     return m_rareNonInheritedData->scrollSnapPort->type;
2026 }
2027
2028 const LengthBox& RenderStyle::scrollPadding() const
2029 {
2030     return m_rareNonInheritedData->scrollSnapPort->scrollPadding;
2031 }
2032
2033 const Length& RenderStyle::scrollPaddingTop() const
2034 {
2035     return scrollPadding().top();
2036 }
2037
2038 const Length& RenderStyle::scrollPaddingBottom() const
2039 {
2040     return scrollPadding().bottom();
2041 }
2042
2043 const Length& RenderStyle::scrollPaddingLeft() const
2044 {
2045     return scrollPadding().left();
2046 }
2047
2048 const Length& RenderStyle::scrollPaddingRight() const
2049 {
2050     return scrollPadding().right();
2051 }
2052
2053 const ScrollSnapAlign& RenderStyle::scrollSnapAlign() const
2054 {
2055     return m_rareNonInheritedData->scrollSnapArea->alignment;
2056 }
2057
2058 const LengthBox& RenderStyle::scrollSnapMargin() const
2059 {
2060     return m_rareNonInheritedData->scrollSnapArea->scrollSnapMargin;
2061 }
2062
2063 const Length& RenderStyle::scrollSnapMarginTop() const
2064 {
2065     return scrollSnapMargin().top();
2066 }
2067
2068 const Length& RenderStyle::scrollSnapMarginBottom() const
2069 {
2070     return scrollSnapMargin().bottom();
2071 }
2072
2073 const Length& RenderStyle::scrollSnapMarginLeft() const
2074 {
2075     return scrollSnapMargin().left();
2076 }
2077
2078 const Length& RenderStyle::scrollSnapMarginRight() const
2079 {
2080     return scrollSnapMargin().right();
2081 }
2082
2083 void RenderStyle::setScrollSnapType(const ScrollSnapType& type)
2084 {
2085     SET_NESTED_VAR(m_rareNonInheritedData, scrollSnapPort, type, type);
2086 }
2087
2088 void RenderStyle::setScrollPaddingTop(Length&& length)
2089 {
2090     SET_NESTED_VAR(m_rareNonInheritedData, scrollSnapPort, scrollPadding.top(), WTFMove(length));
2091 }
2092
2093 void RenderStyle::setScrollPaddingBottom(Length&& length)
2094 {
2095     SET_NESTED_VAR(m_rareNonInheritedData, scrollSnapPort, scrollPadding.bottom(), WTFMove(length));
2096 }
2097
2098 void RenderStyle::setScrollPaddingLeft(Length&& length)
2099 {
2100     SET_NESTED_VAR(m_rareNonInheritedData, scrollSnapPort, scrollPadding.left(), WTFMove(length));
2101 }
2102
2103 void RenderStyle::setScrollPaddingRight(Length&& length)
2104 {
2105     SET_NESTED_VAR(m_rareNonInheritedData, scrollSnapPort, scrollPadding.right(), WTFMove(length));
2106 }
2107
2108 void RenderStyle::setScrollSnapAlign(const ScrollSnapAlign& alignment)
2109 {
2110     SET_NESTED_VAR(m_rareNonInheritedData, scrollSnapArea, alignment, alignment);
2111 }
2112
2113 void RenderStyle::setScrollSnapMarginTop(Length&& length)
2114 {
2115     SET_NESTED_VAR(m_rareNonInheritedData, scrollSnapArea, scrollSnapMargin.top(), WTFMove(length));
2116 }
2117
2118 void RenderStyle::setScrollSnapMarginBottom(Length&& length)
2119 {
2120     SET_NESTED_VAR(m_rareNonInheritedData, scrollSnapArea, scrollSnapMargin.bottom(), WTFMove(length));
2121 }
2122
2123 void RenderStyle::setScrollSnapMarginLeft(Length&& length)
2124 {
2125     SET_NESTED_VAR(m_rareNonInheritedData, scrollSnapArea, scrollSnapMargin.left(), WTFMove(length));
2126 }
2127
2128 void RenderStyle::setScrollSnapMarginRight(Length&& length)
2129 {
2130     SET_NESTED_VAR(m_rareNonInheritedData, scrollSnapArea, scrollSnapMargin.right(), WTFMove(length));
2131 }
2132
2133 #endif
2134
2135 bool RenderStyle::hasReferenceFilterOnly() const
2136 {
2137     if (!hasFilter())
2138         return false;
2139     auto& filterOperations = m_rareNonInheritedData->filter->operations;
2140     return filterOperations.size() == 1 && filterOperations.at(0)->type() == FilterOperation::REFERENCE;
2141 }
2142
2143 void RenderStyle::checkVariablesInCustomProperties()
2144 {
2145     if (!m_rareInheritedData->customProperties->containsVariables)
2146         return;
2147
2148     auto& customPropertyData = m_rareInheritedData.access().customProperties.access();
2149
2150     // Our first pass checks the variables for validity and replaces any properties that became
2151     // invalid with empty values.
2152     auto& customProperties = customPropertyData.values;
2153     HashSet<AtomicString> invalidProperties;
2154     for (auto entry : customProperties) {
2155         if (!entry.value->containsVariables())
2156             continue;
2157         HashSet<AtomicString> seenProperties;
2158         entry.value->checkVariablesForCycles(entry.key, customProperties, seenProperties, invalidProperties);
2159     }
2160     
2161     // Now insert invalid values.
2162     if (!invalidProperties.isEmpty()) {
2163         auto invalidValue = CSSCustomPropertyValue::createInvalid();
2164         for (auto& property : invalidProperties)
2165             customProperties.set(property, invalidValue.copyRef());
2166     }
2167
2168     // Now that all of the properties have been tested for validity and replaced with
2169     // invalid values if they failed, we can perform variable substitution on the valid values.
2170     Vector<Ref<CSSCustomPropertyValue>> resolvedValues;
2171     for (auto entry : customProperties) {
2172         if (!entry.value->containsVariables())
2173             continue;
2174         entry.value->resolveVariableReferences(customProperties, resolvedValues);
2175     }
2176     
2177     // With all results computed, we can now mutate our table to eliminate the variables and
2178     // hold the final values. This way when we inherit, we don't end up resubstituting variables, etc.
2179     for (auto& resolvedValue : resolvedValues)
2180         customProperties.set(resolvedValue->name(), resolvedValue.copyRef());
2181
2182     customPropertyData.containsVariables = false;
2183 }
2184
2185 float RenderStyle::outlineWidth() const
2186 {
2187     if (m_backgroundData->outline.style() == BNONE)
2188         return 0;
2189     if (outlineStyleIsAuto())
2190         return std::max(m_backgroundData->outline.width(), RenderTheme::platformFocusRingWidth());
2191     return m_backgroundData->outline.width();
2192 }
2193
2194 float RenderStyle::outlineOffset() const
2195 {
2196     if (m_backgroundData->outline.style() == BNONE)
2197         return 0;
2198     if (outlineStyleIsAuto())
2199         return (m_backgroundData->outline.offset() + RenderTheme::platformFocusRingOffset(outlineWidth()));
2200     return m_backgroundData->outline.offset();
2201 }
2202
2203 bool RenderStyle::shouldPlaceBlockDirectionScrollbarOnLeft() const
2204 {
2205     return !isLeftToRightDirection() && isHorizontalWritingMode();
2206 }
2207
2208 #if ENABLE(DASHBOARD_SUPPORT)
2209
2210 void RenderStyle::setDashboardRegion(int type, const String& label, Length&& top, Length&& right, Length&& bottom, Length&& left, bool append)
2211 {
2212     if (!append)
2213         m_rareNonInheritedData.access().dashboardRegions.clear();
2214     m_rareNonInheritedData.access().dashboardRegions.append({ label, { WTFMove(top), WTFMove(right), WTFMove(bottom), WTFMove(left) }, type });
2215 }
2216
2217 #endif
2218
2219 Vector<PaintType, 3> RenderStyle::paintTypesForPaintOrder(PaintOrder order)
2220 {
2221     Vector<PaintType, 3> paintOrder;
2222     switch (order) {
2223     case PaintOrder::Normal:
2224         FALLTHROUGH;
2225     case PaintOrder::Fill:
2226         paintOrder.append(PaintType::Fill);
2227         paintOrder.append(PaintType::Stroke);
2228         paintOrder.append(PaintType::Markers);
2229         break;
2230     case PaintOrder::FillMarkers:
2231         paintOrder.append(PaintType::Fill);
2232         paintOrder.append(PaintType::Markers);
2233         paintOrder.append(PaintType::Stroke);
2234         break;
2235     case PaintOrder::Stroke:
2236         paintOrder.append(PaintType::Stroke);
2237         paintOrder.append(PaintType::Fill);
2238         paintOrder.append(PaintType::Markers);
2239         break;
2240     case PaintOrder::StrokeMarkers:
2241         paintOrder.append(PaintType::Stroke);
2242         paintOrder.append(PaintType::Markers);
2243         paintOrder.append(PaintType::Fill);
2244         break;
2245     case PaintOrder::Markers:
2246         paintOrder.append(PaintType::Markers);
2247         paintOrder.append(PaintType::Fill);
2248         paintOrder.append(PaintType::Stroke);
2249         break;
2250     case PaintOrder::MarkersStroke:
2251         paintOrder.append(PaintType::Markers);
2252         paintOrder.append(PaintType::Stroke);
2253         paintOrder.append(PaintType::Fill);
2254         break;
2255     };
2256     return paintOrder;
2257 }
2258
2259 float RenderStyle::computedStrokeWidth(const IntSize& viewportSize) const
2260 {
2261     if (!hasExplicitlySetStrokeWidth())
2262         return textStrokeWidth();
2263     
2264     const Length& length = strokeWidth();
2265
2266     if (length.isPercent()) {
2267         // According to the spec, https://drafts.fxtf.org/paint/#stroke-width, the percentage is relative to the scaled viewport size.
2268         // The scaled viewport size is the geometric mean of the viewport width and height.
2269         ExceptionOr<float> result = length.value() * (viewportSize.width() + viewportSize.height()) / 200.0f;
2270         if (result.hasException())
2271             return 0;
2272         return result.releaseReturnValue();
2273     }
2274     
2275     if (length.isAuto() || !length.isSpecified())
2276         return 0;
2277     
2278     return floatValueForLength(length, viewportSize.width());
2279 }
2280
2281 bool RenderStyle::hasPositiveStrokeWidth() const
2282 {
2283     if (!hasExplicitlySetStrokeWidth())
2284         return textStrokeWidth() > 0;
2285
2286     return strokeWidth().isPositive();
2287 }
2288
2289 } // namespace WebCore