Changeset 238354 in webkit

Timestamp:

Nov 17, 2018 2:12:30 PM (6 years ago)

Author:

Simon Fraser

Message:

Clarify RenderLayerCompositor::hasAnyAdditionalCompositedLayers() and related code.
​https://bugs.webkit.org/show_bug.cgi?id=191810

Reviewed by Zalan Bujtas.

Rename m_compositedLayerCount to m_contentLayersCount and have it track layers other
than the RenderView's layer.

hasAnyAdditionalCompositedLayers() is really about whether we can drop out of compositing
because no content layer is composited, and overlays don't require compositing, so
rename it.

• rendering/RenderLayerCompositor.cpp:

(WebCore::RenderLayerCompositor::updateCompositingLayers):
(WebCore::RenderLayerCompositor::computeCompositingRequirements):
(WebCore::RenderLayerCompositor::needsCompositingForContentOrOverlays const):
(WebCore::RenderLayerCompositor::layerBecameComposited):
(WebCore::RenderLayerCompositor::layerBecameNonComposited):
(WebCore::RenderLayerCompositor::layerTreeAsText):
(WebCore::RenderLayerCompositor::hasAnyAdditionalCompositedLayers const): Deleted.

• rendering/RenderLayerCompositor.h:

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• rendering/RenderLayerCompositor.cpp (modified) (7 diffs)
• rendering/RenderLayerCompositor.h (modified) (4 diffs)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2018-11-17  Simon Fraser  <simon.fraser@apple.com>
+
+        Clarify RenderLayerCompositor::hasAnyAdditionalCompositedLayers() and related code.
+        https://bugs.webkit.org/show_bug.cgi?id=191810
+
+        Reviewed by Zalan Bujtas.
+
+        Rename m_compositedLayerCount to m_contentLayersCount and have it track layers other
+        than the RenderView's layer.
+
+        hasAnyAdditionalCompositedLayers() is really about whether we can drop out of compositing
+        because no content layer is composited, and overlays don't require compositing, so
+        rename it.
+
+        * rendering/RenderLayerCompositor.cpp:
+        (WebCore::RenderLayerCompositor::updateCompositingLayers):
+        (WebCore::RenderLayerCompositor::computeCompositingRequirements):
+        (WebCore::RenderLayerCompositor::needsCompositingForContentOrOverlays const):
+        (WebCore::RenderLayerCompositor::layerBecameComposited):
+        (WebCore::RenderLayerCompositor::layerBecameNonComposited):
+        (WebCore::RenderLayerCompositor::layerTreeAsText):
+        (WebCore::RenderLayerCompositor::hasAnyAdditionalCompositedLayers const): Deleted.
+        * rendering/RenderLayerCompositor.h:
+
 2018-11-17  Simon Fraser  <simon.fraser@apple.com>
 

trunk/Source/WebCore/rendering/RenderLayerCompositor.cpp

@@ -633 +633 @@
 }
 
-bool RenderLayerCompositor::hasAnyAdditionalCompositedLayers(const RenderLayer& rootLayer) const
-{
-    int layerCount = m_compositedLayerCount + page().pageOverlayController().overlayCount();
-    return layerCount > (rootLayer.isComposited() ? 1 : 0);
-}
-
 void RenderLayerCompositor::cancelCompositingLayerUpdate()
 {
@@ -647 +641 @@
 bool RenderLayerCompositor::updateCompositingLayers(CompositingUpdateType updateType, RenderLayer* updateRoot)
 {
-    LOG_WITH_STREAM(Compositing, stream << "RenderLayerCompositor " << this << " updateCompositingLayers " << updateType << " root " << updateRoot);
+    LOG_WITH_STREAM(Compositing, stream << "RenderLayerCompositor " << this << " updateCompositingLayers " << updateType << " contentLayersCount " << m_contentLayersCount);
 
 #if ENABLE(TREE_DEBUGGING)
@@ -740 +734 @@
             // Even when childList is empty, don't drop out of compositing mode if there are
             // composited layers that we didn't hit in our traversal (e.g. because of visibility:hidden).
-            if (childList.isEmpty() && !hasAnyAdditionalCompositedLayers(*updateRoot))
+            if (childList.isEmpty() && !needsCompositingForContentOrOverlays())
                 destroyRootLayer();
             else if (m_rootContentLayer)
@@ -767 +761 @@
         LOG(Compositing, "RenderLayerCompositor::updateCompositingLayers - post");
         showPaintOrderTree(m_renderView.layer());
-        LOG(Compositing, "RenderLayerCompositor::updateCompositingLayers - GraphicsLayers post");
+        LOG(Compositing, "RenderLayerCompositor::updateCompositingLayers - GraphicsLayers post, contentLayersCount %d", m_contentLayersCount);
         showGraphicsLayerTree(m_rootContentLayer.get());
     }
@@ -968 +962 @@
     // if there are composited layers that we didn't hit in our traversal (e.g. because of visibility:hidden).
     RequiresCompositingData rootLayerQueryData;
-    if (layer.isRenderViewLayer() && !childState.subtreeIsCompositing && !requiresCompositingLayer(layer, rootLayerQueryData) && !m_forceCompositingMode && !hasAnyAdditionalCompositedLayers(layer)) {
+    if (layer.isRenderViewLayer() && !childState.subtreeIsCompositing && !requiresCompositingLayer(layer, rootLayerQueryData) && !m_forceCompositingMode && !needsCompositingForContentOrOverlays()) {
         // Don't drop out of compositing on iOS, because we may flash. See <rdar://problem/8348337>.
 #if !PLATFORM(IOS_FAMILY)
@@ -1241 +1235 @@
 }
 
+bool RenderLayerCompositor::needsCompositingForContentOrOverlays() const
+{
+    return m_contentLayersCount + page().pageOverlayController().overlayCount();
+}
+
+void RenderLayerCompositor::layerBecameComposited(const RenderLayer& layer)
+{
+    if (&layer != m_renderView.layer())
+        ++m_contentLayersCount;
+}
+
 void RenderLayerCompositor::layerBecameNonComposited(const RenderLayer& layer)
 {
     // Inform the inspector that the given RenderLayer was destroyed.
+    // FIXME: "destroyed" is a misnomer.
     InspectorInstrumentation::renderLayerDestroyed(&page(), layer);
 
-    ASSERT(m_compositedLayerCount > 0);
-    --m_compositedLayerCount;
+    if (&layer == m_renderView.layer()) {
+        ASSERT(m_contentLayersCount > 0);
+        --m_contentLayersCount;
+    }
 }
 
@@ -1908 +1916 @@
     // Dump an empty layer tree only if the only composited layer is the main frame's tiled backing,
     // so that tests expecting us to drop out of accelerated compositing when there are no layers succeed.
-    if (!hasAnyAdditionalCompositedLayers(rootRenderLayer()) && documentUsesTiledBacking() && !(layerTreeBehavior & LayerTreeAsTextIncludeTileCaches))
+    if (!hasContentCompositingLayers() && documentUsesTiledBacking() && !(layerTreeBehavior & LayerTreeAsTextIncludeTileCaches))
         layerTreeText = emptyString();
 

trunk/Source/WebCore/rendering/RenderLayerCompositor.h

@@ -106 +106 @@
     bool inForcedCompositingMode() const { return m_forceCompositingMode; }
 
+    // True when some content element other than the root is composited.
+    bool hasContentCompositingLayers() const { return m_contentLayersCount; }
+
     // Returns true if the accelerated compositing is enabled
     bool hasAcceleratedCompositing() const { return m_hasAcceleratedCompositing; }
@@ -217 +220 @@
     void clearBackingForAllLayers();
     
-    void layerBecameComposited(const RenderLayer&) { ++m_compositedLayerCount; }
+    void layerBecameComposited(const RenderLayer&);
     void layerBecameNonComposited(const RenderLayer&);
     
@@ -387 +390 @@
 
     void appendDocumentOverlayLayers(Vector<Ref<GraphicsLayer>>&);
-    bool hasAnyAdditionalCompositedLayers(const RenderLayer& rootLayer) const;
+
+    bool needsCompositingForContentOrOverlays() const;
 
     void ensureRootLayer();
@@ -506 +510 @@
     bool m_isTrackingRepaints { false }; // Used for testing.
 
-    int m_compositedLayerCount { 0 };
+    unsigned m_contentLayersCount { 0 };
     unsigned m_layersWithTiledBackingCount { 0 };
     unsigned m_layerFlushCount { 0 };