cc/trees/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_TREES_LAYER_TREE_HOST_COMMON_H_
   6 #define CC_TREES_LAYER_TREE_HOST_COMMON_H_
   7
   8 #include <vector>
   9
  10 #include "base/memory/ref_counted.h"
  11 #include "cc/base/cc_export.h"
  12 #include "cc/base/scoped_ptr_vector.h"
  13 #include "cc/layers/layer_lists.h"
  14 #include "ui/gfx/rect.h"
  15 #include "ui/gfx/transform.h"
  16 #include "ui/gfx/vector2d.h"
  17
  18 namespace cc {
  19
  20 class LayerImpl;
  21 class Layer;
  22
  23 class CC_EXPORT LayerTreeHostCommon {
  24  public:
  25   static gfx::Rect CalculateVisibleRect(gfx::Rect target_surface_rect,
  26                                         gfx::Rect layer_bound_rect,
  27                                         const gfx::Transform& transform);
  28
  29   static void CalculateDrawProperties(
  30       Layer* root_layer,
  31       gfx::Size device_viewport_size,
  32       float device_scale_factor,
  33       float page_scale_factor,
  34       Layer* page_scale_application_layer,
  35       int max_texture_size,
  36       bool can_use_lcd_text,
  37       LayerList* render_surface_layer_list);
  38   static void CalculateDrawProperties(
  39       LayerImpl* root_layer,
  40       gfx::Size device_viewport_size,
  41       float device_scale_factor,
  42       float page_scale_factor,
  43       LayerImpl* page_scale_application_layer,
  44       int max_texture_size,
  45       bool can_use_lcd_text,
  46       LayerImplList* render_surface_layer_list,
  47       bool update_tile_priorities);
  48
  49   // Performs hit testing for a given render_surface_layer_list.
  50   static LayerImpl* FindLayerThatIsHitByPoint(
  51       gfx::PointF screen_space_point,
  52       const LayerImplList& render_surface_layer_list);
  53
  54   static LayerImpl* FindLayerThatIsHitByPointInTouchHandlerRegion(
  55       gfx::PointF screen_space_point,
  56       const LayerImplList& render_surface_layer_list);
  57
  58   static bool LayerHasTouchEventHandlersAt(gfx::PointF screen_space_point,
  59                                            LayerImpl* layer_impl);
  60
  61   template <typename LayerType>
  62   static bool RenderSurfaceContributesToTarget(LayerType*,
  63                                                int target_surface_layer_id);
  64
  65   template <class Function, typename LayerType>
  66   static void CallFunctionForSubtree(LayerType* root_layer);
  67
  68   // Returns a layer with the given id if one exists in the subtree starting
  69   // from the given root layer (including mask and replica layers).
  70   template <typename LayerType>
  71   static LayerType* FindLayerInSubtree(LayerType* root_layer, int layer_id);
  72
  73   static Layer* get_child_as_raw_ptr(
  74       const LayerList& children,
  75       size_t index) {
  76     return children[index].get();
  77   }
  78
  79   static LayerImpl* get_child_as_raw_ptr(
  80       const OwnedLayerImplList& children,
  81       size_t index) {
  82     return children[index];
  83   }
  84
  85   struct ScrollUpdateInfo {
  86     int layer_id;
  87     gfx::Vector2d scroll_delta;
  88   };
  89 };
  90
  91 struct CC_EXPORT ScrollAndScaleSet {
  92   ScrollAndScaleSet();
  93   ~ScrollAndScaleSet();
  94
  95   std::vector<LayerTreeHostCommon::ScrollUpdateInfo> scrolls;
  96   float page_scale_delta;
  97 };
  98
  99 template <typename LayerType>
 100 bool LayerTreeHostCommon::RenderSurfaceContributesToTarget(
 101     LayerType* layer,
 102     int target_surface_layer_id) {
 103   // A layer will either contribute its own content, or its render surface's
 104   // content, to the target surface. The layer contributes its surface's content
 105   // when both the following are true:
 106   //  (1) The layer actually has a render surface, and
 107   //  (2) The layer's render surface is not the same as the target surface.
 108   //
 109   // Otherwise, the layer just contributes itself to the target surface.
 110
 111   return layer->render_surface() && layer->id() != target_surface_layer_id;
 112 }
 113
 114 template <typename LayerType>
 115 LayerType* LayerTreeHostCommon::FindLayerInSubtree(LayerType* root_layer,
 116                                                    int layer_id) {
 117   if (root_layer->id() == layer_id)
 118     return root_layer;
 119
 120   if (root_layer->mask_layer() && root_layer->mask_layer()->id() == layer_id)
 121     return root_layer->mask_layer();
 122
 123   if (root_layer->replica_layer() &&
 124       root_layer->replica_layer()->id() == layer_id)
 125     return root_layer->replica_layer();
 126
 127   for (size_t i = 0; i < root_layer->children().size(); ++i) {
 128     if (LayerType* found = FindLayerInSubtree(
 129             get_child_as_raw_ptr(root_layer->children(), i), layer_id))
 130       return found;
 131   }
 132   return NULL;
 133 }
 134
 135 template <class Function, typename LayerType>
 136 void LayerTreeHostCommon::CallFunctionForSubtree(LayerType* root_layer) {
 137   Function()(root_layer);
 138
 139   if (LayerType* mask_layer = root_layer->mask_layer())
 140     Function()(mask_layer);
 141   if (LayerType* replica_layer = root_layer->replica_layer()) {
 142     Function()(replica_layer);
 143     if (LayerType* mask_layer = replica_layer->mask_layer())
 144       Function()(mask_layer);
 145   }
 146
 147   for (size_t i = 0; i < root_layer->children().size(); ++i) {
 148     CallFunctionForSubtree<Function>(
 149         get_child_as_raw_ptr(root_layer->children(), i));
 150   }
 151 }
 152
 153 }  // namespace cc
 154
 155 #endif  // CC_TREES_LAYER_TREE_HOST_COMMON_H_