cc/layer_tree_host_common.h

   1 // Copyright 2011 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CC_LAYER_TREE_HOST_COMMON_H_
   6 #define CC_LAYER_TREE_HOST_COMMON_H_
   7
   8 #include "base/memory/ref_counted.h"
   9 #include "cc/cc_export.h"
  10 #include "cc/scoped_ptr_vector.h"
  11 #include "ui/gfx/rect.h"
  12 #include "ui/gfx/vector2d.h"
  13 #include <public/WebTransformationMatrix.h>
  14
  15 namespace cc {
  16
  17 class LayerImpl;
  18 class LayerSorter;
  19 class Layer;
  20
  21 class CC_EXPORT LayerTreeHostCommon {
  22 public:
  23     static gfx::Rect calculateVisibleRect(const gfx::Rect& targetSurfaceRect, const gfx::Rect& layerBoundRect, const WebKit::WebTransformationMatrix&);
  24
  25     static void calculateDrawTransforms(Layer* rootLayer, const gfx::Size& deviceViewportSize, float deviceScaleFactor, float pageScaleFactor, int maxTextureSize, std::vector<scoped_refptr<Layer> >& renderSurfaceLayerList);
  26     static void calculateDrawTransforms(LayerImpl* rootLayer, const gfx::Size& deviceViewportSize, float deviceScaleFactor, float pageScaleFactor, LayerSorter*, int maxTextureSize, std::vector<LayerImpl*>& renderSurfaceLayerList);
  27
  28     // Performs hit testing for a given renderSurfaceLayerList.
  29     static LayerImpl* findLayerThatIsHitByPoint(const gfx::PointF& screenSpacePoint, std::vector<LayerImpl*>& renderSurfaceLayerList);
  30
  31     template<typename LayerType> static bool renderSurfaceContributesToTarget(LayerType*, int targetSurfaceLayerID);
  32
  33     // Returns a layer with the given id if one exists in the subtree starting
  34     // from the given root layer (including mask and replica layers).
  35     template<typename LayerType> static LayerType* findLayerInSubtree(LayerType* rootLayer, int layerId);
  36
  37     static Layer* getChildAsRawPtr(const std::vector<scoped_refptr<Layer> >& children, size_t index)
  38     {
  39         return children[index].get();
  40     }
  41
  42     static LayerImpl* getChildAsRawPtr(const ScopedPtrVector<LayerImpl>& children, size_t index)
  43     {
  44         return children[index];
  45     }
  46
  47     struct ScrollUpdateInfo {
  48         int layerId;
  49         gfx::Vector2d scrollDelta;
  50     };
  51 };
  52
  53 struct CC_EXPORT ScrollAndScaleSet {
  54     ScrollAndScaleSet();
  55     ~ScrollAndScaleSet();
  56
  57     std::vector<LayerTreeHostCommon::ScrollUpdateInfo> scrolls;
  58     float pageScaleDelta;
  59 };
  60
  61 template<typename LayerType>
  62 bool LayerTreeHostCommon::renderSurfaceContributesToTarget(LayerType* layer, int targetSurfaceLayerID)
  63 {
  64     // A layer will either contribute its own content, or its render surface's content, to
  65     // the target surface. The layer contributes its surface's content when both the
  66     // following are true:
  67     //  (1) The layer actually has a renderSurface, and
  68     //  (2) The layer's renderSurface is not the same as the targetSurface.
  69     //
  70     // Otherwise, the layer just contributes itself to the target surface.
  71
  72     return layer->renderSurface() && layer->id() != targetSurfaceLayerID;
  73 }
  74
  75 template<typename LayerType>
  76 LayerType* LayerTreeHostCommon::findLayerInSubtree(LayerType* rootLayer, int layerId)
  77 {
  78     if (rootLayer->id() == layerId)
  79         return rootLayer;
  80
  81     if (rootLayer->maskLayer() && rootLayer->maskLayer()->id() == layerId)
  82         return rootLayer->maskLayer();
  83
  84     if (rootLayer->replicaLayer() && rootLayer->replicaLayer()->id() == layerId)
  85         return rootLayer->replicaLayer();
  86
  87     for (size_t i = 0; i < rootLayer->children().size(); ++i) {
  88         if (LayerType* found = findLayerInSubtree(getChildAsRawPtr(rootLayer->children(), i), layerId))
  89             return found;
  90     }
  91     return 0;
  92 }
  93
  94 }  // namespace cc
  95
  96 #endif  // CC_LAYER_TREE_HOST_COMMON_H_