Move LayerSorter to exist locally only in layer_tree_host_common

cc/layer_tree_host_common.cc

 // Copyright 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/layer_tree_host_common.h"
 
 #include <algorithm>
 
+#include "base/debug/trace_event.h"
 #include "cc/layer.h"
 #include "cc/layer_impl.h"
 #include "cc/layer_iterator.h"
 #include "cc/layer_sorter.h"
 #include "cc/math_util.h"
 #include "cc/render_surface.h"
 #include "cc/render_surface_impl.h"
 #include "ui/gfx/point_conversions.h"
 #include "ui/gfx/rect_conversions.h"
 #include "ui/gfx/transform.h"
 
 namespace cc {
 
 ScrollAndScaleSet::ScrollAndScaleSet()
 {
 }
 
 ScrollAndScaleSet::~ScrollAndScaleSet()
 {
 }
 
+static void sortLayers(std::vector<Layer*>::iterator first, std::vector<Layer*>::iterator end, LayerSorter* layerSorter)
+{
+    NOTREACHED();
+}
+
+static void sortLayers(std::vector<LayerImpl*>::iterator first, std::vector<LayerImpl*>::iterator end, LayerSorter* layerSorter)
+{
+    DCHECK(layerSorter);
+    TRACE_EVENT0("cc", "layer_tree_host_common::sortLayers");
+    layerSorter->sort(first, end);
+}
+
 gfx::Rect LayerTreeHostCommon::calculateVisibleRect(const gfx::Rect& targetSurfaceRect, const gfx::Rect& layerBoundRect, const gfx::Transform& transform)
 {
     // Is this layer fully contained within the target surface?
     gfx::Rect layerInSurfaceSpace = MathUtil::mapClippedRect(transform, layerBoundRect);
     if (targetSurfaceRect.Contains(layerInSurfaceSpace))
         return layerBoundRect;
 
     // If the layer doesn't fill up the entire surface, then find the part of
     // the surface rect where the layer could be visible. This avoids trying to
     // project surface rect points that are behind the projection point.
@@ skipping 343 matching lines @@
     if (maskLayer)
         maskLayer->setContentsScale(contentsScale);
 
     Layer* replicaMaskLayer = layer->replicaLayer() ? layer->replicaLayer()->maskLayer() : 0;
     if (replicaMaskLayer)
         replicaMaskLayer->setContentsScale(contentsScale);
 }
 
 // Recursively walks the layer tree starting at the given node and computes all the
 // necessary transformations, clipRects, render surfaces, etc.
-template<typename LayerType, typename LayerList, typename RenderSurfaceType, typename LayerSorter>
+template<typename LayerType, typename LayerList, typename RenderSurfaceType>
 static void calculateDrawPropertiesInternal(LayerType* layer, const gfx::Transform& parentMatrix,
     const gfx::Transform& fullHierarchyMatrix, const gfx::Transform& currentScrollCompensationMatrix,
     const gfx::Rect& clipRectFromAncestor, bool ancestorClipsSubtree,
     RenderSurfaceType* nearestAncestorThatMovesPixels, LayerList& renderSurfaceLayerList, LayerList& layerList,
     LayerSorter* layerSorter, int maxTextureSize, float deviceScaleFactor, float pageScaleFactor, gfx::Rect& drawableContentRectOfSubtree)
 {
     // This function computes the new matrix transformations recursively for this
     // layer and all its descendants. It also computes the appropriate render surfaces.
     // Some important points to remember:
     //
@@ skipping 285 matching lines @@
 
     if (!layerShouldBeSkipped(layer))
         descendants.push_back(layer);
 
     gfx::Transform nextScrollCompensationMatrix = computeScrollCompensationMatrixForChildren(layer, parentMatrix, currentScrollCompensationMatrix);;
 
     gfx::Rect accumulatedDrawableContentRectOfChildren;
     for (size_t i = 0; i < layer->children().size(); ++i) {
         LayerType* child = LayerTreeHostCommon::getChildAsRawPtr(layer->children(), i);
         gfx::Rect drawableContentRectOfChildSubtree;
-        calculateDrawPropertiesInternal<LayerType, LayerList, RenderSurfaceType, LayerSorter>(child, sublayerMatrix, nextHierarchyMatrix, nextScrollCompensationMatrix,
-                                                                                              clipRectForSubtree, subtreeShouldBeClipped, nearestAncestorThatMovesPixels,
-                                                                                              renderSurfaceLayerList, descendants, layerSorter, maxTextureSize, deviceScaleFactor, pageScaleFactor, drawableContentRectOfChildSubtree);
+        calculateDrawPropertiesInternal<LayerType, LayerList, RenderSurfaceType>(child, sublayerMatrix, nextHierarchyMatrix, nextScrollCompensationMatrix,
+                                                                                 clipRectForSubtree, subtreeShouldBeClipped, nearestAncestorThatMovesPixels,
+                                                                                 renderSurfaceLayerList, descendants, layerSorter, maxTextureSize, deviceScaleFactor, pageScaleFactor, drawableContentRectOfChildSubtree);
         if (!drawableContentRectOfChildSubtree.IsEmpty()) {
             accumulatedDrawableContentRectOfChildren.Union(drawableContentRectOfChildSubtree);
             if (child->renderSurface())
                 descendants.push_back(child);
         }
     }
 
     // Compute the total drawableContentRect for this subtree (the rect is in targetSurface space)
     gfx::Rect localDrawableContentRectOfSubtree = accumulatedDrawableContentRectOfChildren;
     if (layer->drawsContent())
@@ skipping 97 matching lines @@
 
     markLayerAsUpdated(layer);
 
     // If neither this layer nor any of its children were added, early out.
     if (sortingStartIndex == descendants.size())
         return;
 
     // If preserves-3d then sort all the descendants in 3D so that they can be
     // drawn from back to front. If the preserves-3d property is also set on the parent then
     // skip the sorting as the parent will sort all the descendants anyway.
-    if (descendants.size() && layer->preserves3D() && (!layer->parent() || !layer->parent()->preserves3D()))
+    if (layerSorter && descendants.size() && layer->preserves3D() && (!layer->parent() || !layer->parent()->preserves3D()))
         sortLayers(descendants.begin() + sortingStartIndex, descendants.end(), layerSorter);
 
     if (layer->renderSurface())
         drawableContentRectOfSubtree = gfx::ToEnclosingRect(layer->renderSurface()->drawableContentRect());
     else
         drawableContentRectOfSubtree = localDrawableContentRectOfSubtree;
 
     if (layer->hasContributingDelegatedRenderPasses())
         layer->renderTarget()->renderSurface()->addContributingDelegatedRenderPassLayer(layer);
 }
 
 void LayerTreeHostCommon::calculateDrawProperties(Layer* rootLayer, const gfx::Size& deviceViewportSize, float deviceScaleFactor, float pageScaleFactor, int maxTextureSize, std::vector<scoped_refptr<Layer> >& renderSurfaceLayerList)
 {
     gfx::Rect totalDrawableContentRect;
     gfx::Transform identityMatrix;
     gfx::Transform deviceScaleTransform;
     deviceScaleTransform.Scale(deviceScaleFactor, deviceScaleFactor);
     std::vector<scoped_refptr<Layer> > dummyLayerList;
 
     // The root layer's renderSurface should receive the deviceViewport as the initial clipRect.
     bool subtreeShouldBeClipped = true;
     gfx::Rect deviceViewportRect(gfx::Point(), deviceViewportSize);
 
     // This function should have received a root layer.
     DCHECK(isRootLayer(rootLayer));
 
-    cc::calculateDrawPropertiesInternal<Layer, std::vector<scoped_refptr<Layer> >, RenderSurface, void>(
+    cc::calculateDrawPropertiesInternal<Layer, std::vector<scoped_refptr<Layer> >, RenderSurface>(
         rootLayer, deviceScaleTransform, identityMatrix, identityMatrix,
         deviceViewportRect, subtreeShouldBeClipped, 0, renderSurfaceLayerList,
         dummyLayerList, 0, maxTextureSize,
         deviceScaleFactor, pageScaleFactor, totalDrawableContentRect);
 
     // The dummy layer list should not have been used.
     DCHECK(dummyLayerList.size() == 0);
     // A root layer renderSurface should always exist after calculateDrawProperties.
     DCHECK(rootLayer->renderSurface());
 }
 
-void LayerTreeHostCommon::calculateDrawProperties(LayerImpl* rootLayer, const gfx::Size& deviceViewportSize, float deviceScaleFactor, float pageScaleFactor, LayerSorter* layerSorter, int maxTextureSize, std::vector<LayerImpl*>& renderSurfaceLayerList)
+void LayerTreeHostCommon::calculateDrawProperties(LayerImpl* rootLayer, const gfx::Size& deviceViewportSize, float deviceScaleFactor, float pageScaleFactor, int maxTextureSize, std::vector<LayerImpl*>& renderSurfaceLayerList)
 {
     gfx::Rect totalDrawableContentRect;
     gfx::Transform identityMatrix;
     gfx::Transform deviceScaleTransform;
     deviceScaleTransform.Scale(deviceScaleFactor, deviceScaleFactor);
     std::vector<LayerImpl*> dummyLayerList;
-
+    LayerSorter layerSorter;
+    
     // The root layer's renderSurface should receive the deviceViewport as the initial clipRect.
     bool subtreeShouldBeClipped = true;
     gfx::Rect deviceViewportRect(gfx::Point(), deviceViewportSize);
 
     // This function should have received a root layer.
     DCHECK(isRootLayer(rootLayer));
 
-    cc::calculateDrawPropertiesInternal<LayerImpl, std::vector<LayerImpl*>, RenderSurfaceImpl, LayerSorter>(
+    cc::calculateDrawPropertiesInternal<LayerImpl, std::vector<LayerImpl*>, RenderSurfaceImpl>(
         rootLayer, deviceScaleTransform, identityMatrix, identityMatrix,
         deviceViewportRect, subtreeShouldBeClipped, 0, renderSurfaceLayerList,
-        dummyLayerList, layerSorter, maxTextureSize,
+        dummyLayerList, &layerSorter, maxTextureSize,
         deviceScaleFactor, pageScaleFactor, totalDrawableContentRect);
 
     // The dummy layer list should not have been used.
     DCHECK(dummyLayerList.size() == 0);
     // A root layer renderSurface should always exist after calculateDrawProperties.
     DCHECK(rootLayer->renderSurface());
 }
 
 static bool pointHitsRect(const gfx::PointF& screenSpacePoint, const gfx::Transform& localSpaceToScreenSpaceTransform, gfx::RectF localSpaceRect)
 {
@@ skipping 112 matching lines @@
 
         foundLayer = currentLayer;
         break;
     }
 
     // This can potentially return 0, which means the screenSpacePoint did not successfully hit test any layers, not even the root layer.
     return foundLayer;
 }
 
 }  // namespace cc