Compute if a layer is drawn without LayerTree hierarchy

cc/trees/property_tree_builder.cc

 // Copyright 2014 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/trees/property_tree_builder.h"
 
 #include <stddef.h>
 
 #include <map>
 #include <set>
@@ skipping 30 matching lines @@
   const LayerType* outer_viewport_scroll_layer;
   const LayerType* overscroll_elasticity_layer;
   gfx::Vector2dF elastic_overscroll;
   float page_scale_factor;
   bool in_subtree_of_page_scale_layer;
   bool affected_by_inner_viewport_bounds_delta;
   bool affected_by_outer_viewport_bounds_delta;
   bool should_flatten;
   bool target_is_clipped;
   bool is_hidden;
+  bool contributes_to_copy_request;
   const gfx::Transform* device_transform;
   gfx::Vector2dF scroll_compensation_adjustment;
   gfx::Transform compound_transform_since_render_target;
   bool axis_align_since_render_target;
   int sequence_number;
 };
 
 template <typename LayerType>
 struct DataForRecursionFromChild {
   int num_copy_requests_in_subtree;
@@ skipping 506 matching lines @@
     data_for_children->compound_transform_since_render_target *=
         layer->transform();
     return false;
   }
 
   EffectNode node;
   node.owner_id = layer->id();
   node.data.opacity = layer->opacity();
   node.data.screen_space_opacity = layer->opacity();
   node.data.has_render_surface = should_create_render_surface;
+  // A node contributes to copy request when it is in the subtree of a layer
+  // with a copy request and is visible inside the copy request.
+  data_for_children->contributes_to_copy_request =
+      layer->HasCopyRequest() ||
+      (data_from_ancestor.contributes_to_copy_request &&
+       layer->opacity() != 0.f);
+  node.data.contributes_to_copy_request =

[ajuma, 2016/01/15 15:02:47]

Does this value need to get updated on the compositor side after copy requests
are serviced?

[jaydasika, 2016/01/19 20:02:49]

Done.

+      data_for_children->contributes_to_copy_request;
 
   if (!is_root) {
     // The effect node's transform id is used only when we create a render
     // surface. So, we can leave the default value when we don't create a render
     // surface.
     if (should_create_render_surface) {
       // In this case, we will create a transform node, so it's safe to use the
       // next available id from the transform tree as this effect node's
       // transform id.
       node.data.transform_id =
@@ skipping 43 matching lines @@
     layer->set_draw_blend_mode(SkXfermode::kSrcOver_Mode);
   } else {
     layer->set_draw_blend_mode(layer->blend_mode());
   }
 
   bool created_transform_node = AddTransformNodeIfNeeded(
       data_from_parent, layer, created_render_surface, &data_for_children);
   AddClipNodeIfNeeded(data_from_parent, layer, created_render_surface,
                       created_transform_node, &data_for_children);
 
-  data_for_children.is_hidden =
-      layer->hide_layer_and_subtree() || data_from_parent.is_hidden;
-  layer->set_is_hidden_from_property_trees(data_for_children.is_hidden);
-
   for (size_t i = 0; i < layer->children().size(); ++i) {
     if (!layer->child_at(i)->scroll_parent()) {
       DataForRecursionFromChild<LayerType> data_from_child;
       BuildPropertyTreesInternal(layer->child_at(i), data_for_children,
                                  &data_from_child);
       data_to_parent->Merge(data_from_child);
     } else {
       // The child should be included in its scroll parent's list of scroll
       // children.
       DCHECK(layer->child_at(i)->scroll_parent()->scroll_children()->count(
@@ skipping 71 matching lines @@
   data_for_recursion.outer_viewport_scroll_layer = outer_viewport_scroll_layer;
   data_for_recursion.overscroll_elasticity_layer = overscroll_elasticity_layer;
   data_for_recursion.elastic_overscroll = elastic_overscroll;
   data_for_recursion.page_scale_factor = page_scale_factor;
   data_for_recursion.in_subtree_of_page_scale_layer = false;
   data_for_recursion.affected_by_inner_viewport_bounds_delta = false;
   data_for_recursion.affected_by_outer_viewport_bounds_delta = false;
   data_for_recursion.should_flatten = false;
   data_for_recursion.target_is_clipped = false;
   data_for_recursion.is_hidden = false;
+  data_for_recursion.contributes_to_copy_request = false;
   data_for_recursion.device_transform = &device_transform;
 
   data_for_recursion.transform_tree->clear();
   data_for_recursion.clip_tree->clear();
   data_for_recursion.effect_tree->clear();
   data_for_recursion.compound_transform_since_render_target = gfx::Transform();
   data_for_recursion.axis_align_since_render_target = true;
   data_for_recursion.sequence_number = property_trees->sequence_number;
   data_for_recursion.transform_tree->set_device_scale_factor(
       device_scale_factor);
@@ skipping 50 matching lines @@
     const gfx::Transform& device_transform,
     PropertyTrees* property_trees) {
   BuildPropertyTreesTopLevelInternal(
       root_layer, page_scale_layer, inner_viewport_scroll_layer,
       outer_viewport_scroll_layer, overscroll_elasticity_layer,
       elastic_overscroll, page_scale_factor, device_scale_factor, viewport,
       device_transform, property_trees);
 }
 
 }  // namespace cc