Compute if a layer is clipped outside CalcDrawProps

cc/layers/draw_properties.h

 // Copyright 2012 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.
 
 #ifndef CC_LAYERS_DRAW_PROPERTIES_H_
 #define CC_LAYERS_DRAW_PROPERTIES_H_
 
 #include "base/memory/scoped_ptr.h"
 #include "cc/trees/occlusion.h"
 #include "third_party/skia/include/core/SkXfermode.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/gfx/transform.h"
 
 namespace cc {
 
 // Container for properties that layers need to compute before they can be
 // drawn.
 template <typename LayerType>
 struct CC_EXPORT DrawProperties {
   DrawProperties()
       : opacity(0.f),
         blend_mode(SkXfermode::kSrcOver_Mode),
         opacity_is_animating(false),
         screen_space_opacity_is_animating(false),
         target_space_transform_is_animating(false),
         screen_space_transform_is_animating(false),
         can_use_lcd_text(false),
         is_clipped(false),
+        is_clipped_from_property_trees(false),
         render_target(nullptr),
         num_unclipped_descendants(0),
         layer_or_descendant_has_copy_request(false),
         layer_or_descendant_has_input_handler(false),
         has_child_with_a_scroll_parent(false),
         index_of_first_descendants_addition(0),
         num_descendants_added(0),
         index_of_first_render_surface_layer_list_addition(0),
         num_render_surfaces_added(0),
         last_drawn_render_surface_layer_list_id(0),
@@ skipping 27 matching lines @@
   bool opacity_is_animating;
   bool screen_space_opacity_is_animating;
   bool target_space_transform_is_animating;
   bool screen_space_transform_is_animating;
 
   // True if the layer can use LCD text.
   bool can_use_lcd_text;
 
   // True if the layer needs to be clipped by clip_rect.
   bool is_clipped;
+  bool is_clipped_from_property_trees;

[ajuma, 2015/07/07 17:58:48]

So far I think we've been adding 'from_property_trees' values directly on
Layer/LayerImpl rather than adding them to DrawProperties. Also, the setter for
this on Layer will need to SetNeedsPushProperties when this value changes.

[enne (OOO), 2015/07/07 18:25:48]

This is a bit odd to have both at this point in time where we are only doing CDP
on the main thread in unit tests.  Does is_clipped ever change on the compositor
thread?  It looks like the CHECK_EQ is expecting it not to.

Also, draw properties aren't pushed in general.  Can this be a layer property? 

I think what I'd like to see is have Layer::is_clipped set by the property tree
builder and pushed to LayerImpl::is_clipped.  If there are somehow unit tests
that are still calling main thread CDP only and are failing, then maybe just
make sure they call the property tree builder too.

How's that sound?

[jaydasika, 2015/07/07 18:35:28]

moved it from draw_properties to Layer/LayerImpl.

 
   // The layer whose coordinate space this layer draws into. This can be
   // either the same layer (draw_properties_.render_target == this) or an
   // ancestor of this layer.
   LayerType* render_target;
 
   // This rect is a bounding box around what part of the layer is visible, in
   // the layer's coordinate space.
   gfx::Rect visible_layer_rect;
 
@@ skipping 48 matching lines @@
   float maximum_animation_contents_scale;
 
   // The scale during the layer animation start at which content should be
   // rastered at to be crisp.
   float starting_animation_contents_scale;
 };
 
 }  // namespace cc
 
 #endif  // CC_LAYERS_DRAW_PROPERTIES_H_