Changeset 252070 in webkit

Timestamp:

Nov 5, 2019, 12:11:32 PM (7 years ago)

Author:

Simon Fraser

Message:

Content can disappear with a combination of <video> with controls and clipping
​https://bugs.webkit.org/show_bug.cgi?id=203834
Source/WebCore:

rdar://problem/56559648

Reviewed by Zalan Bujtas.

<video> with controls triggered a bug where a backing-sharing layer also claimed
that it didn't need any backing store. RenderLayerCompositor::requiresOwnBackingStore()
could early-return with 'false' if a layer had an indirect compositing reason of "Clipping",
while also backing-sharing. We need to check for backing-sharing first.

Test: compositing/shared-backing/clipping-and-shared-backing.html

• rendering/RenderLayerBacking.cpp:

(WebCore::RenderLayerBacking::setBackingSharingLayers):

• rendering/RenderLayerCompositor.cpp:

(WebCore::RenderLayerCompositor::requiresOwnBackingStore const):

LayoutTests:

Reviewed by Zalan Bujtas.

• compositing/shared-backing/clipping-and-shared-backing-expected.html: Added.
• compositing/shared-backing/clipping-and-shared-backing.html: Added.

Location:

trunk

Files:

• LayoutTests/ChangeLog (modified) (1 diff)
• LayoutTests/compositing/shared-backing/clipping-and-shared-backing-expected.html (added)
• LayoutTests/compositing/shared-backing/clipping-and-shared-backing.html (added)
• Source/WebCore/ChangeLog (modified) (1 diff)
• Source/WebCore/rendering/RenderLayerBacking.cpp (modified) (1 diff)
• Source/WebCore/rendering/RenderLayerCompositor.cpp (modified) (2 diffs)

trunk/LayoutTests/ChangeLog

@@ +1 @@
+2019-11-05  Simon Fraser  <simon.fraser@apple.com>
+
+        Content can disappear with a combination of <video> with controls and clipping
+        https://bugs.webkit.org/show_bug.cgi?id=203834
+
+        Reviewed by Zalan Bujtas.
+
+        * compositing/shared-backing/clipping-and-shared-backing-expected.html: Added.
+        * compositing/shared-backing/clipping-and-shared-backing.html: Added.
+
 2019-11-05  Said Abou-Hallawa  <sabouhallawa@apple.com>
 

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2019-11-05  Simon Fraser  <simon.fraser@apple.com>
+
+        Content can disappear with a combination of <video> with controls and clipping
+        https://bugs.webkit.org/show_bug.cgi?id=203834
+        rdar://problem/56559648
+
+        Reviewed by Zalan Bujtas.
+        
+        <video> with controls triggered a bug where a backing-sharing layer also claimed
+        that it didn't need any backing store. RenderLayerCompositor::requiresOwnBackingStore()
+        could early-return with 'false' if a layer had an indirect compositing reason of "Clipping",
+        while also backing-sharing. We need to check for backing-sharing first.
+
+        Test: compositing/shared-backing/clipping-and-shared-backing.html
+
+        * rendering/RenderLayerBacking.cpp:
+        (WebCore::RenderLayerBacking::setBackingSharingLayers):
+        * rendering/RenderLayerCompositor.cpp:
+        (WebCore::RenderLayerCompositor::requiresOwnBackingStore const):
+
 2019-11-05  Said Abou-Hallawa  <sabouhallawa@apple.com>
 

trunk/Source/WebCore/rendering/RenderLayerBacking.cpp

@@ -295 +295 @@
     clearBackingSharingLayerProviders(m_backingSharingLayers);
 
-    if (sharingLayers != m_backingSharingLayers)
+    if (sharingLayers != m_backingSharingLayers) {
+        if (sharingLayers.size())
+            setRequiresOwnBackingStore(true);
         setContentsNeedDisplay(); // This could be optimized to only repaint rects for changed layers.
+    }
 
     auto oldSharingLayers = WTFMove(m_backingSharingLayers);

trunk/Source/WebCore/rendering/RenderLayerCompositor.cpp

@@ -2423 +2423 @@
         return true;
 
+    if (layer.isComposited() && layer.backing()->hasBackingSharingLayers())
+        return true;
+
     if (layer.mustCompositeForIndirectReasons()) {
         IndirectCompositingReason reason = layer.indirectCompositingReason();
@@ -2433 +2436 @@
     }
 
+    // FIXME: We really need to keep track of the ancestor layer that has its own backing store.
     if (!ancestorCompositedBounds.contains(layerCompositedBoundsInAncestor))
-        return true;
-
-    if (layer.isComposited() && layer.backing()->hasBackingSharingLayers())
         return true;