Changeset 172183 in webkit

Timestamp:

Aug 6, 2014, 4:05:34 PM (11 years ago)

Author:

Simon Fraser

Message:

REGRESSION (r168119): Album flipping animation doesn’t work
​https://bugs.webkit.org/show_bug.cgi?id=132801
Source/WebCore:

<rdar://problem/16878497>, <rdar://problem/17908085>

Reviewed by Dean Jackson.

In r168119 I avoided creating backing store for backface-visibility:hidden unless
some ancestor was 3d-transformed. However, when starting transitions or animations
that apply transforms, we don't do a layout, and therefore don't update the RenderLayer
flags that mark an ancestor as having a transform. This broke various content which
used backface-visibility:hidden for "flip" animations.

Make a low-risk fix that looks for the pattern of CSS properties used for flipping,
making a compositing layer for backface-visibility:hidden if the stacking context element
has transform-style: preserve-3d.

Test: compositing/backing/backface-visibility-flip.html

• rendering/RenderLayerCompositor.cpp:

(WebCore::RenderLayerCompositor::requiresCompositingForBackfaceVisibility):

LayoutTests:

Reviewed by Dean Jackson.

Test that starts a transform animation and dumps layers.

• compositing/backing/backface-visibility-flip-expected.txt: Added.
• compositing/backing/backface-visibility-flip.html: Added.

Location:

trunk

Files:

• LayoutTests/ChangeLog (modified) (1 diff)
• LayoutTests/compositing/backing/backface-visibility-flip-expected.txt (added)
• LayoutTests/compositing/backing/backface-visibility-flip.html (added)
• Source/WebCore/ChangeLog (modified) (1 diff)
• Source/WebCore/rendering/RenderLayerCompositor.cpp (modified) (1 diff)

trunk/LayoutTests/ChangeLog

@@ +1 @@
+2014-08-06  Simon Fraser  <simon.fraser@apple.com>
+
+        REGRESSION (r168119): Album flipping animation doesn’t work
+        https://bugs.webkit.org/show_bug.cgi?id=132801
+
+        Reviewed by Dean Jackson.
+        
+        Test that starts a transform animation and dumps layers.
+
+        * compositing/backing/backface-visibility-flip-expected.txt: Added.
+        * compositing/backing/backface-visibility-flip.html: Added.
+
 2014-08-06  Brent Fulgham  <bfulgham@apple.com>
 

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2014-08-06  Simon Fraser  <simon.fraser@apple.com>
+
+        REGRESSION (r168119): Album flipping animation doesn’t work
+        https://bugs.webkit.org/show_bug.cgi?id=132801
+        <rdar://problem/16878497>, <rdar://problem/17908085>
+
+        Reviewed by Dean Jackson.
+        
+        In r168119 I avoided creating backing store for backface-visibility:hidden unless
+        some ancestor was 3d-transformed. However, when starting transitions or animations
+        that apply transforms, we don't do a layout, and therefore don't update the RenderLayer
+        flags that mark an ancestor as having a transform. This broke various content which
+        used backface-visibility:hidden for "flip" animations.
+        
+        Make a low-risk fix that looks for the pattern of CSS properties used for flipping,
+        making a compositing layer for backface-visibility:hidden if the stacking context element
+        has transform-style: preserve-3d.
+
+        Test: compositing/backing/backface-visibility-flip.html
+
+        * rendering/RenderLayerCompositor.cpp:
+        (WebCore::RenderLayerCompositor::requiresCompositingForBackfaceVisibility):
+
 2014-08-06  Brent Fulgham  <bfulgham@apple.com>
 

trunk/Source/WebCore/rendering/RenderLayerCompositor.cpp

@@ -2393 +2393 @@
         return false;
 
-    return renderer.style().backfaceVisibility() == BackfaceVisibilityHidden && renderer.layer()->has3DTransformedAncestor();
+    if (renderer.style().backfaceVisibility() != BackfaceVisibilityHidden)
+        return false;
+        
+    if (renderer.layer()->has3DTransformedAncestor())
+        return true;
+    
+    // FIXME: workaround for webkit.org/b/132801
+    RenderLayer* stackingContext = renderer.layer()->stackingContainer();
+    if (stackingContext && stackingContext->renderer().style().transformStyle3D() == TransformStyle3DPreserve3D)
+        return true;
+
+    return false;
 }