compositor-worker: plumb element id and mutable properties

third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp

 /*
  * Copyright (C) 2009, 2010, 2011 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 47 matching lines @@
 #include "platform/LengthFunctions.h"
 #include "platform/RuntimeEnabledFeatures.h"
 #include "platform/fonts/FontCache.h"
 #include "platform/geometry/TransformState.h"
 #include "platform/graphics/BitmapImage.h"
 #include "platform/graphics/GraphicsContext.h"
 #include "platform/graphics/paint/ClipDisplayItem.h"
 #include "platform/graphics/paint/CullRect.h"
 #include "platform/graphics/paint/PaintController.h"
 #include "platform/graphics/paint/TransformDisplayItem.h"
+#include "public/platform/WebCompositorMutableProperties.h"
 #include "wtf/CurrentTime.h"
 #include "wtf/text/StringBuilder.h"
 
 namespace blink {
 
 using namespace HTMLNames;
 
 static IntRect clipBox(LayoutBox* layoutObject);
 
 static IntRect contentsRect(const LayoutObject* layoutObject)
@@ skipping 472 matching lines @@
     if (layoutObject->isLayoutPart()) {
         if (PaintLayerCompositor::parentFrameContentLayers(toLayoutPart(layoutObject)))
             layerConfigChanged = true;
     }
 
     // Changes to either the internal hierarchy or the mask layer have an impact
     // on painting phases, so we need to update when either are updated.
     if (layerConfigChanged || maskLayerChanged)
         updatePaintingPhases();
 
+    updateElementIdAndMutableProperties();
+
     return layerConfigChanged;
 }
 
 static IntRect clipBox(LayoutBox* layoutObject)
 {
     LayoutRect result = LayoutRect(LayoutRect::infiniteIntRect());
     if (layoutObject->hasOverflowClip())
         result = layoutObject->overflowClipRect(LayoutPoint());
 
     if (layoutObject->hasClip())
@@ skipping 167 matching lines @@
         m_owningLayer.scrollableArea()->positionOverflowControls();
 
     if (RuntimeEnabledFeatures::cssCompositingEnabled()) {
         updateLayerBlendMode(layoutObject()->styleRef());
         updateIsRootForIsolatedGroup();
     }
 
     updateContentsRect();
     updateBackgroundColor();
     updateDrawsContent();
+    updateElementIdAndMutableProperties();
     updateContentsOpaque();
     updateAfterPartResize();
     updateRenderingContext();
     updateShouldFlattenTransform();
     updateChildrenTransform();
     updateScrollParent(scrollParent());
     registerScrollingLayers();
 
     updateCompositingReasons();
 }
@@ skipping 742 matching lines @@
     // selection layer (if they exist) as not flattening. Having them flatten
     // causes unclipped render surfaces which cause bugs.
     // http://crbug.com/521768
     if (hasScrollingLayer()) {
         m_scrollingContentsLayer->setShouldFlattenTransform(false);
         if (m_scrollingBlockSelectionLayer)
             m_scrollingBlockSelectionLayer->setShouldFlattenTransform(false);
     }
 }
 
+void CompositedLayerMapping::updateElementIdAndMutableProperties()
+{
+    if (!RuntimeEnabledFeatures::compositorWorkerEnabled())
+        return;
+
+    TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("compositor-worker"), "CompositedLayerMapping::updateElementId()");
+
+    uint64_t elementId = 0;
+    uint32_t mainMutableProperties = WebCompositorMutablePropertyNone;
+    uint32_t scrollMutableProperties = WebCompositorMutablePropertyNone;
+
+    if (m_owningLayer.layoutObject()->style()->hasCompositorProxy()) {
+        if (Node* owningNode = m_owningLayer.layoutObject()->generatingNode()) {
+            elementId = DOMNodeIds::idForNode(owningNode);
+            mainMutableProperties = WebCompositorMutablePropertyOpacity | WebCompositorMutablePropertyTransform;
+            scrollMutableProperties = WebCompositorMutablePropertyScrollLeft | WebCompositorMutablePropertyScrollTop;
+        }
+    }
+
+    m_graphicsLayer->setElementId(elementId);

[chrishtr, 2015/11/24 16:22:50]

Can an element which is indirectly composited end up with a CW? If so you need
to add CW as a reason to prevent squashing.

[Ian Vollick, 2015/11/25 18:28:45]

Nope, a CompositorProxy is a direct compositing reason.

+    m_graphicsLayer->setMutableProperties(mainMutableProperties);
+
+    if (m_scrollingContentsLayer.get()) {
+        m_scrollingContentsLayer->setElementId(elementId);
+        m_scrollingContentsLayer->setMutableProperties(scrollMutableProperties);
+    }
+}
+
 bool CompositedLayerMapping::updateForegroundLayer(bool needsForegroundLayer)
 {
     bool layerChanged = false;
     if (needsForegroundLayer) {
         if (!m_foregroundLayer) {
             m_foregroundLayer = createGraphicsLayer(CompositingReasonLayerForForeground);
             m_foregroundLayer->setPaintingPhase(GraphicsLayerPaintForeground);
             layerChanged = true;
         }
     } else if (m_foregroundLayer) {
@@ skipping 1002 matching lines @@
     } else if (graphicsLayer == m_scrollingBlockSelectionLayer.get()) {
         name = "Scrolling Block Selection Layer";
     } else {
         ASSERT_NOT_REACHED();
     }
 
     return name;
 }
 
 } // namespace blink