Make compositingState explicit

Source/core/rendering/RenderObject.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  *           (C) 2004 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2009 Google Inc. All rights reserved.
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 1349 matching lines @@
     }
 
     if (repaintContainer->hasFilter() && repaintContainer->layer() && repaintContainer->layer()->requiresFullLayerImageForFilters()) {
         repaintContainer->layer()->setFilterBackendNeedsRepaintingInRect(r);
         return;
     }
 
     RenderView* v = view();
     if (repaintContainer->isRenderView()) {
         ASSERT(repaintContainer == v);
-        bool viewHasCompositedLayer = v->hasLayer() && v->layer()->isComposited();
+        bool viewHasCompositedLayer = v->hasLayer() && v->layer()->compositingState() == PaintsIntoOwnBacking;
         if (!viewHasCompositedLayer) {
             IntRect repaintRectangle = r;
             if (viewHasCompositedLayer &&  v->layer()->transform())
                 repaintRectangle = v->layer()->transform()->mapRect(r);
             v->repaintViewRectangle(repaintRectangle);
             return;
         }
     }
 
     if (v->usesCompositing()) {
-        ASSERT(repaintContainer->hasLayer() && repaintContainer->layer()->isComposited());
+        ASSERT(repaintContainer->hasLayer() && repaintContainer->layer()->compositingState() == PaintsIntoOwnBacking);
         repaintContainer->layer()->setBackingNeedsRepaintInRect(r);
     }
 }
 
 void RenderObject::repaint() const
 {
     // Don't repaint if we're unrooted (note that view() still returns the view when unrooted)
     RenderView* view;
     if (!isRooted(&view))
         return;
@@ skipping 344 matching lines @@
 {
     if (!isText() && style && !RuntimeEnabledFeatures::webAnimationsCSSEnabled()) {
         setStyle(animation()->updateAnimations(this, style.get()));
         return;
     }
     setStyle(style);
 }
 
 StyleDifference RenderObject::adjustStyleDifference(StyleDifference diff, unsigned contextSensitiveProperties) const
 {
-    // If transform changed, and we are not composited, need to do a layout.
+    // If transform changed, and the layer does not paint into its own separate backing, then we need to do a layout.
+    // FIXME: The comment above is what the code does, but it is technically not following spec. This means we will
+    // not to layout for 3d transforms, but we should be invoking a simplified relayout. Is it possible we are avoiding
+    // doing this for some performance reason at this time?
     if (contextSensitiveProperties & ContextSensitivePropertyTransform) {
         // Text nodes share style with their parents but transforms don't apply to them,
         // hence the !isText() check.
         // FIXME: when transforms are taken into account for overflow, we will need to do a layout.
-        if (!isText() && (!hasLayer() || !toRenderLayerModelObject(this)->layer()->isComposited())) {
+        if (!isText() && (!hasLayer() || toRenderLayerModelObject(this)->layer()->compositingState() != PaintsIntoOwnBacking)) {
             // We need to set at least SimplifiedLayout, but if PositionedMovementOnly is already set
             // then we actually need SimplifiedLayoutAndPositionedMovement.
             if (!hasLayer())
                 diff = StyleDifferenceLayout; // FIXME: Do this for now since SimplifiedLayout cannot handle updating floating objects lists.
             else if (diff < StyleDifferenceLayoutPositionedMovementOnly)
                 diff = StyleDifferenceSimplifiedLayout;
             else if (diff < StyleDifferenceSimplifiedLayout)
                 diff = StyleDifferenceSimplifiedLayoutAndPositionedMovement;
         } else if (diff < StyleDifferenceRecompositeLayer)
             diff = StyleDifferenceRecompositeLayer;
     }
 
-    // If opacity changed, and we are not composited, need to repaint (also
+    // If opacity or filters changed, and the layer does not paint into its own separate backing, then we need to repaint (also
     // ignoring text nodes)
     if (contextSensitiveProperties & ContextSensitivePropertyOpacity) {
-        if (!isText() && (!hasLayer() || !toRenderLayerModelObject(this)->layer()->isComposited()))
+        if (!isText() && (!hasLayer() || toRenderLayerModelObject(this)->layer()->compositingState() != PaintsIntoOwnBacking))
             diff = StyleDifferenceRepaintLayer;
         else if (diff < StyleDifferenceRecompositeLayer)
             diff = StyleDifferenceRecompositeLayer;
     }
-
     if ((contextSensitiveProperties & ContextSensitivePropertyFilter) && hasLayer()) {
         RenderLayer* layer = toRenderLayerModelObject(this)->layer();
-        if (!layer->isComposited() || layer->paintsWithFilters())
+        if (layer->compositingState() != PaintsIntoOwnBacking || layer->paintsWithFilters())
             diff = StyleDifferenceRepaintLayer;
         else if (diff < StyleDifferenceRecompositeLayer)
             diff = StyleDifferenceRecompositeLayer;
     }
 
     // The answer to requiresLayer() for plugins, iframes, and canvas can change without the actual
     // style changing, since it depends on whether we decide to composite these elements. When the
     // layer status of one of these elements changes, we need to force a layout.
     if (diff == StyleDifferenceEqual && style() && isLayerModelObject()) {
         if (hasLayer() != toRenderLayerModelObject(this)->requiresLayer())
@@ skipping 940 matching lines @@
 void RenderObject::updateDragState(bool dragOn)
 {
     bool valueChanged = (dragOn != isDragging());
     setIsDragging(dragOn);
     if (valueChanged && node() && (style()->affectedByDrag() || (node()->isElementNode() && toElement(node())->childrenAffectedByDrag())))
         node()->setNeedsStyleRecalc();
     for (RenderObject* curr = firstChild(); curr; curr = curr->nextSibling())
         curr->updateDragState(dragOn);
 }
 
-bool RenderObject::isComposited() const
+CompositingState RenderObject::compositingState() const
 {
-    return hasLayer() && toRenderLayerModelObject(this)->layer()->isComposited();
+    return hasLayer() ? toRenderLayerModelObject(this)->layer()->compositingState() : NotComposited;
 }
 
 bool RenderObject::hitTest(const HitTestRequest& request, HitTestResult& result, const HitTestLocation& locationInContainer, const LayoutPoint& accumulatedOffset, HitTestFilter hitTestFilter)
 {
     bool inside = false;
     if (hitTestFilter != HitTestSelf) {
         // First test the foreground layer (lines and inlines).
         inside = nodeAtPoint(request, result, locationInContainer, accumulatedOffset, HitTestForeground);
 
         // Test floats next.
@@ skipping 606 matching lines @@
 {
     if (object1) {
         const WebCore::RenderObject* root = object1;
         while (root->parent())
             root = root->parent();
         root->showRenderTreeAndMark(object1, "*", object2, "-", 0);
     }
 }
 
 #endif