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<dl class="meta">
<dt>Revision</dt> <dd><a href="http://trac.webkit.org/projects/webkit/changeset/188514">188514</a></dd>
<dt>Author</dt> <dd>simon.fraser@apple.com</dd>
<dt>Date</dt> <dd>2015-08-15 13:13:24 -0700 (Sat, 15 Aug 2015)</dd>
</dl>
<h3>Log Message</h3>
<pre>Have will-change create stacking context when necessary
https://bugs.webkit.org/show_bug.cgi?id=148060
Reviewed by Zalan Bujtas.
Source/WebCore:
If will-change includes a property whose non-initial value can create
stacking context, create stacking context for that element.
Test: fast/css/will-change/will-change-creates-stacking-context.html
* css/StyleResolver.cpp:
(WebCore::StyleResolver::adjustRenderStyle):
* rendering/style/RenderStyle.h: Add willChangeCreatesStackingContext(),
which on most cases is a fast, inlined 'return false'. Otherwise ask
the WillChangeData.
* rendering/style/WillChangeData.cpp:
(WebCore::propertyCreatesStackingContext):
(WebCore::WillChangeData::createsStackingContext):
* rendering/style/WillChangeData.h:
LayoutTests:
Ref test for will-change creating stacking context.
* fast/css/will-change/resources/will-change-stacking-helper.js: Added.
(makeStackingBlock):
* fast/css/will-change/will-change-creates-stacking-context-expected.html: Added.
* fast/css/will-change/will-change-creates-stacking-context.html: Added.
* platform/efl/TestExpectations: Mark image failure on EFL, since some CSS
properties in the test are disabled there.</pre>
<h3>Modified Paths</h3>
<ul>
<li><a href="#trunkLayoutTestsChangeLog">trunk/LayoutTests/ChangeLog</a></li>
<li><a href="#trunkLayoutTestsplatformeflTestExpectations">trunk/LayoutTests/platform/efl/TestExpectations</a></li>
<li><a href="#trunkLayoutTestsplatformmacmavericksTestExpectations">trunk/LayoutTests/platform/mac-mavericks/TestExpectations</a></li>
<li><a href="#trunkSourceWebCoreChangeLog">trunk/Source/WebCore/ChangeLog</a></li>
<li><a href="#trunkSourceWebCorecssStyleResolvercpp">trunk/Source/WebCore/css/StyleResolver.cpp</a></li>
<li><a href="#trunkSourceWebCorerenderingstyleRenderStyleh">trunk/Source/WebCore/rendering/style/RenderStyle.h</a></li>
<li><a href="#trunkSourceWebCorerenderingstyleWillChangeDatacpp">trunk/Source/WebCore/rendering/style/WillChangeData.cpp</a></li>
<li><a href="#trunkSourceWebCorerenderingstyleWillChangeDatah">trunk/Source/WebCore/rendering/style/WillChangeData.h</a></li>
</ul>
<h3>Added Paths</h3>
<ul>
<li>trunk/LayoutTests/fast/css/will-change/</li>
<li>trunk/LayoutTests/fast/css/will-change/resources/</li>
<li><a href="#trunkLayoutTestsfastcsswillchangeresourceswillchangestackinghelperjs">trunk/LayoutTests/fast/css/will-change/resources/will-change-stacking-helper.js</a></li>
<li><a href="#trunkLayoutTestsfastcsswillchangewillchangecreatesstackingcontextexpectedhtml">trunk/LayoutTests/fast/css/will-change/will-change-creates-stacking-context-expected.html</a></li>
<li><a href="#trunkLayoutTestsfastcsswillchangewillchangecreatesstackingcontexthtml">trunk/LayoutTests/fast/css/will-change/will-change-creates-stacking-context.html</a></li>
</ul>
</div>
<div id="patch">
<h3>Diff</h3>
<a id="trunkLayoutTestsChangeLog"></a>
<div class="modfile"><h4>Modified: trunk/LayoutTests/ChangeLog (188513 => 188514)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/LayoutTests/ChangeLog 2015-08-15 18:09:01 UTC (rev 188513)
+++ trunk/LayoutTests/ChangeLog 2015-08-15 20:13:24 UTC (rev 188514)
</span><span class="lines">@@ -1,3 +1,19 @@
</span><ins>+2015-08-15 Simon Fraser <simon.fraser@apple.com>
+
+ Have will-change create stacking context when necessary
+ https://bugs.webkit.org/show_bug.cgi?id=148060
+
+ Reviewed by Zalan Bujtas.
+
+ Ref test for will-change creating stacking context.
+
+ * fast/css/will-change/resources/will-change-stacking-helper.js: Added.
+ (makeStackingBlock):
+ * fast/css/will-change/will-change-creates-stacking-context-expected.html: Added.
+ * fast/css/will-change/will-change-creates-stacking-context.html: Added.
+ * platform/efl/TestExpectations: Mark image failure on EFL, since some CSS
+ properties in the test are disabled there.
+
</ins><span class="cx"> 2015-08-14 Simon Fraser <simon.fraser@apple.com>
</span><span class="cx">
</span><span class="cx"> Implement parsing for CSS will-change
</span></span></pre></div>
<a id="trunkLayoutTestsfastcsswillchangeresourceswillchangestackinghelperjs"></a>
<div class="addfile"><h4>Added: trunk/LayoutTests/fast/css/will-change/resources/will-change-stacking-helper.js (0 => 188514)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/LayoutTests/fast/css/will-change/resources/will-change-stacking-helper.js (rev 0)
+++ trunk/LayoutTests/fast/css/will-change/resources/will-change-stacking-helper.js 2015-08-15 20:13:24 UTC (rev 188514)
</span><span class="lines">@@ -0,0 +1,51 @@
</span><ins>+var willChangeValues = [
+ { 'property' : 'auto', 'stacking' : false },
+ { 'property' : 'background', 'stacking' : false },
+ { 'property' : 'will-change', 'stacking' : false },
+
+ { 'property' : 'clip-path', 'stacking' : true },
+ { 'property' : 'mask', 'stacking' : true },
+ { 'property' : 'opacity', 'stacking' : true },
+ { 'property' : 'position', 'stacking' : true },
+ { 'property' : 'z-index', 'stacking' : true },
+ { 'property' : 'mix-blend-mode', 'stacking' : true },
+ { 'property' : 'isolation', 'stacking' : true },
+ { 'property' : 'perspective', 'stacking' : true },
+ { 'property' : 'transform', 'stacking' : true },
+ { 'property' : 'transform-style', 'stacking' : true },
+
+ { 'property' : '-webkit-filter', 'stacking' : true },
+ { 'property' : '-webkit-clip-path', 'stacking' : true },
+ { 'property' : '-webkit-backface-visibility', 'stacking' : true },
+ { 'property' : '-webkit-box-reflect', 'stacking' : true },
+ { 'property' : '-webkit-backdrop-filter', 'stacking' : true },
+ { 'property' : '-webkit-mask', 'stacking' : true },
+ { 'property' : '-webkit-mask-image', 'stacking' : true },
+ { 'property' : '-webkit-mask-box-image', 'stacking' : true },
+ { 'property' : '-webkit-transform', 'stacking' : true },
+ { 'property' : '-webkit-transform-style', 'stacking' : true },
+ { 'property' : '-webkit-flow-from', 'stacking' : true },
+];
+
+function makeStackingBlock(stackingProperty, value)
+{
+ var container = document.createElement('div');
+ container.className = 'container';
+
+ var potentialStackingContext = document.createElement('div');
+ potentialStackingContext.className = 'potential-stacking-context';
+ potentialStackingContext.style[stackingProperty] = value;
+
+ var child = document.createElement('div');
+ child.className = 'child';
+ potentialStackingContext.appendChild(child);
+
+ container.appendChild(potentialStackingContext);
+
+ var interposer = document.createElement('div');
+ interposer.className = 'interposer';
+ container.appendChild(interposer);
+
+ document.body.appendChild(container);
+}
+
</ins></span></pre></div>
<a id="trunkLayoutTestsfastcsswillchangewillchangecreatesstackingcontextexpectedhtml"></a>
<div class="addfile"><h4>Added: trunk/LayoutTests/fast/css/will-change/will-change-creates-stacking-context-expected.html (0 => 188514)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/LayoutTests/fast/css/will-change/will-change-creates-stacking-context-expected.html (rev 0)
+++ trunk/LayoutTests/fast/css/will-change/will-change-creates-stacking-context-expected.html 2015-08-15 20:13:24 UTC (rev 188514)
</span><span class="lines">@@ -0,0 +1,57 @@
</span><ins>+<!DOCTYPE html>
+
+<html>
+<head>
+ <style>
+ .container {
+ display: inline-block;
+ margin: 25px;
+ width: 50px;
+ height: 50px;
+ position: relative;
+ border: 1px solid black;
+ }
+
+ .container div {
+ width: 100%;
+ height: 100%;
+ }
+
+ .potential-stacking-context {
+ position: relative;
+ z-index: auto;
+ background-color: silver;
+ }
+
+ .child {
+ position: absolute;
+ top: 10px;
+ left: 10px;
+ z-index: 1;
+ background-color: orange;
+ }
+
+ .interposer {
+ position: absolute;
+ top: 20px;
+ left: 20px;
+ z-index: 0;
+ background-color: green;
+ }
+ </style>
+
+ <script src="resources/will-change-stacking-helper.js"></script>
+ <script>
+ function doTest()
+ {
+ for (value of willChangeValues) {
+ makeStackingBlock('z-index', value.stacking ? '0' : 'auto');
+ }
+ }
+
+ window.addEventListener('load', doTest, false);
+ </script>
+</head>
+<body>
+</body>
+</html>
</ins></span></pre></div>
<a id="trunkLayoutTestsfastcsswillchangewillchangecreatesstackingcontexthtml"></a>
<div class="addfile"><h4>Added: trunk/LayoutTests/fast/css/will-change/will-change-creates-stacking-context.html (0 => 188514)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/LayoutTests/fast/css/will-change/will-change-creates-stacking-context.html (rev 0)
+++ trunk/LayoutTests/fast/css/will-change/will-change-creates-stacking-context.html 2015-08-15 20:13:24 UTC (rev 188514)
</span><span class="lines">@@ -0,0 +1,57 @@
</span><ins>+<!DOCTYPE html>
+
+<html>
+<head>
+ <style>
+ .container {
+ display: inline-block;
+ margin: 25px;
+ width: 50px;
+ height: 50px;
+ position: relative;
+ border: 1px solid black;
+ }
+
+ .container div {
+ width: 100%;
+ height: 100%;
+ }
+
+ .potential-stacking-context {
+ position: relative;
+ z-index: auto;
+ background-color: silver;
+ }
+
+ .child {
+ position: absolute;
+ top: 10px;
+ left: 10px;
+ z-index: 1;
+ background-color: orange;
+ }
+
+ .interposer {
+ position: absolute;
+ top: 20px;
+ left: 20px;
+ z-index: 0;
+ background-color: green;
+ }
+ </style>
+
+ <script src="resources/will-change-stacking-helper.js"></script>
+ <script>
+ function doTest()
+ {
+ for (value of willChangeValues) {
+ makeStackingBlock('will-change', value.property);
+ }
+ }
+
+ window.addEventListener('load', doTest, false);
+ </script>
+</head>
+<body>
+</body>
+</html>
</ins></span></pre></div>
<a id="trunkLayoutTestsplatformeflTestExpectations"></a>
<div class="modfile"><h4>Modified: trunk/LayoutTests/platform/efl/TestExpectations (188513 => 188514)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/LayoutTests/platform/efl/TestExpectations 2015-08-15 18:09:01 UTC (rev 188513)
+++ trunk/LayoutTests/platform/efl/TestExpectations 2015-08-15 20:13:24 UTC (rev 188514)
</span><span class="lines">@@ -404,6 +404,9 @@
</span><span class="cx"> # CSS image-resolution is not yet enabled.
</span><span class="cx"> webkit.org/b/85262 fast/css/image-resolution
</span><span class="cx">
</span><ins>+# Some CSS properties not supported on EFL
+fast/css/will-change/will-change-creates-stacking-context.html [ ImageOnlyFailure ]
+
</ins><span class="cx"> # Perf tests are really slow in debug builds and there are few benefits in running them.
</span><span class="cx"> [ Debug ] perf [ WontFix ]
</span><span class="cx">
</span></span></pre></div>
<a id="trunkLayoutTestsplatformmacmavericksTestExpectations"></a>
<div class="modfile"><h4>Modified: trunk/LayoutTests/platform/mac-mavericks/TestExpectations (188513 => 188514)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/LayoutTests/platform/mac-mavericks/TestExpectations 2015-08-15 18:09:01 UTC (rev 188513)
+++ trunk/LayoutTests/platform/mac-mavericks/TestExpectations 2015-08-15 20:13:24 UTC (rev 188514)
</span><span class="lines">@@ -9,6 +9,7 @@
</span><span class="cx"> # No support for Filters Level 2
</span><span class="cx"> compositing/media-controls-bar-appearance.html [ Skip ]
</span><span class="cx"> compositing/media-controls-bar-appearance-big.html [ Skip ]
</span><ins>+fast/css/will-change/will-change-creates-stacking-context.html [ ImageOnlyFailure ]
</ins><span class="cx">
</span><span class="cx"> # No support for non-HLS Media Selection Group
</span><span class="cx"> media/accessiblity-describes-video.html [ Skip ]
</span></span></pre></div>
<a id="trunkSourceWebCoreChangeLog"></a>
<div class="modfile"><h4>Modified: trunk/Source/WebCore/ChangeLog (188513 => 188514)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/Source/WebCore/ChangeLog 2015-08-15 18:09:01 UTC (rev 188513)
+++ trunk/Source/WebCore/ChangeLog 2015-08-15 20:13:24 UTC (rev 188514)
</span><span class="lines">@@ -1,3 +1,25 @@
</span><ins>+2015-08-15 Simon Fraser <simon.fraser@apple.com>
+
+ Have will-change create stacking context when necessary
+ https://bugs.webkit.org/show_bug.cgi?id=148060
+
+ Reviewed by Zalan Bujtas.
+
+ If will-change includes a property whose non-initial value can create
+ stacking context, create stacking context for that element.
+
+ Test: fast/css/will-change/will-change-creates-stacking-context.html
+
+ * css/StyleResolver.cpp:
+ (WebCore::StyleResolver::adjustRenderStyle):
+ * rendering/style/RenderStyle.h: Add willChangeCreatesStackingContext(),
+ which on most cases is a fast, inlined 'return false'. Otherwise ask
+ the WillChangeData.
+ * rendering/style/WillChangeData.cpp:
+ (WebCore::propertyCreatesStackingContext):
+ (WebCore::WillChangeData::createsStackingContext):
+ * rendering/style/WillChangeData.h:
+
</ins><span class="cx"> 2015-08-15 Commit Queue <commit-queue@webkit.org>
</span><span class="cx">
</span><span class="cx"> Unreviewed, rolling out r188508.
</span></span></pre></div>
<a id="trunkSourceWebCorecssStyleResolvercpp"></a>
<div class="modfile"><h4>Modified: trunk/Source/WebCore/css/StyleResolver.cpp (188513 => 188514)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/Source/WebCore/css/StyleResolver.cpp 2015-08-15 18:09:01 UTC (rev 188513)
+++ trunk/Source/WebCore/css/StyleResolver.cpp 2015-08-15 20:13:24 UTC (rev 188514)
</span><span class="lines">@@ -1269,6 +1269,7 @@
</span><span class="cx"> || style.position() == StickyPosition
</span><span class="cx"> || (style.position() == FixedPosition && documentSettings() && documentSettings()->fixedPositionCreatesStackingContext())
</span><span class="cx"> || style.hasFlowFrom()
</span><ins>+ || style.willChangeCreatesStackingContext()
</ins><span class="cx"> ))
</span><span class="cx"> style.setZIndex(0);
</span><span class="cx">
</span></span></pre></div>
<a id="trunkSourceWebCorerenderingstyleRenderStyleh"></a>
<div class="modfile"><h4>Modified: trunk/Source/WebCore/rendering/style/RenderStyle.h (188513 => 188514)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/Source/WebCore/rendering/style/RenderStyle.h 2015-08-15 18:09:01 UTC (rev 188513)
+++ trunk/Source/WebCore/rendering/style/RenderStyle.h 2015-08-15 20:13:24 UTC (rev 188514)
</span><span class="lines">@@ -113,7 +113,6 @@
</span><span class="cx"> class StyleInheritedData;
</span><span class="cx"> class StyleResolver;
</span><span class="cx"> class TransformationMatrix;
</span><del>-class WillChangeData;
</del><span class="cx">
</span><span class="cx"> struct ScrollSnapPoints;
</span><span class="cx">
</span><span class="lines">@@ -1802,6 +1801,14 @@
</span><span class="cx"> WillChangeData* willChange() const { return rareNonInheritedData->m_willChange.get(); }
</span><span class="cx"> void setWillChange(PassRefPtr<WillChangeData>);
</span><span class="cx">
</span><ins>+ bool willChangeCreatesStackingContext() const
+ {
+ if (!willChange())
+ return false;
+
+ return willChange()->createsStackingContext();
+ }
+
</ins><span class="cx"> const AtomicString& hyphenString() const;
</span><span class="cx">
</span><span class="cx"> bool inheritedNotEqual(const RenderStyle*) const;
</span></span></pre></div>
<a id="trunkSourceWebCorerenderingstyleWillChangeDatacpp"></a>
<div class="modfile"><h4>Modified: trunk/Source/WebCore/rendering/style/WillChangeData.cpp (188513 => 188514)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/Source/WebCore/rendering/style/WillChangeData.cpp 2015-08-15 18:09:01 UTC (rev 188513)
+++ trunk/Source/WebCore/rendering/style/WillChangeData.cpp 2015-08-15 20:13:24 UTC (rev 188514)
</span><span class="lines">@@ -60,6 +60,55 @@
</span><span class="cx"> return false;
</span><span class="cx"> }
</span><span class="cx">
</span><ins>+// "If any non-initial value of a property would create a stacking context on the element,
+// specifying that property in will-change must create a stacking context on the element."
+static bool propertyCreatesStackingContext(CSSPropertyID property)
+{
+ switch (property) {
+ case CSSPropertyClipPath:
+ case CSSPropertyWebkitClipPath:
+ case CSSPropertyMask:
+ case CSSPropertyOpacity:
+ case CSSPropertyPosition:
+ case CSSPropertyZIndex:
+ case CSSPropertyWebkitBackfaceVisibility:
+ case CSSPropertyWebkitBoxReflect:
+#if ENABLE(CSS_COMPOSITING)
+ case CSSPropertyMixBlendMode:
+ case CSSPropertyIsolation:
+#endif
+ case CSSPropertyWebkitFilter:
+#if ENABLE(FILTERS_LEVEL_2)
+ case CSSPropertyWebkitBackdropFilter:
+#endif
+ case CSSPropertyWebkitMask:
+ case CSSPropertyWebkitMaskImage:
+ case CSSPropertyWebkitMaskBoxImage:
+ case CSSPropertyPerspective:
+ case CSSPropertyTransform:
+ case CSSPropertyTransformStyle:
+ case CSSPropertyWebkitTransformStyle:
+#if ENABLE(CSS_REGIONS)
+ case CSSPropertyWebkitFlowFrom:
+#endif
+#if ENABLE(ACCELERATED_OVERFLOW_SCROLLING)
+ case CSSPropertyWebkitOverflowScrolling:
+#endif
+ return true;
+ default:
+ return false;
+ }
+}
+
+bool WillChangeData::createsStackingContext() const
+{
+ for (const auto& feature : m_animatableFeatures) {
+ if (feature.feature() == Property && propertyCreatesStackingContext(feature.property()))
+ return true;
+ }
+ return false;
+}
+
</ins><span class="cx"> void WillChangeData::addFeature(Feature feature, CSSPropertyID propertyID)
</span><span class="cx"> {
</span><span class="cx"> ASSERT(feature == Property || propertyID == CSSPropertyInvalid);
</span></span></pre></div>
<a id="trunkSourceWebCorerenderingstyleWillChangeDatah"></a>
<div class="modfile"><h4>Modified: trunk/Source/WebCore/rendering/style/WillChangeData.h (188513 => 188514)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/Source/WebCore/rendering/style/WillChangeData.h 2015-08-15 18:09:01 UTC (rev 188513)
+++ trunk/Source/WebCore/rendering/style/WillChangeData.h 2015-08-15 20:13:24 UTC (rev 188514)
</span><span class="lines">@@ -53,6 +53,7 @@
</span><span class="cx"> bool containsScrollPosition() const;
</span><span class="cx"> bool containsContents() const;
</span><span class="cx"> bool containsProperty(CSSPropertyID) const;
</span><ins>+ bool createsStackingContext() const;
</ins><span class="cx">
</span><span class="cx"> enum Feature {
</span><span class="cx"> ScrollPosition,
</span></span></pre>
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