Mark layers that can use LCD text based on layer transform and opacity.

cc/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_DRAW_PROPERTIES_H_
 #define CC_DRAW_PROPERTIES_H_
 
 #include "base/memory/scoped_ptr.h"
 #include "ui/gfx/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, typename RenderSurfaceType>
 struct CC_EXPORT DrawProperties {
     DrawProperties()
         : opacity(0)
         , 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)
         , render_target(0)
     {
     }
 
     // Transforms objects from content space to target surface space, where
     // this layer would be drawn.
     gfx::Transform target_space_transform;
 
     // Transforms objects from content space to screen space (viewport space).
     gfx::Transform screen_space_transform;
 
     // DrawProperties::opacity may be different than LayerType::opacity,
     // particularly in the case when a renderSurface re-parents the layer's
     // opacity, or when opacity is compounded by the hierarchy.
     float opacity;
 
     // XXXIsAnimating flags are used to indicate whether the drawProperties
     // are actually meaningful on the main thread. When the properties are
     // animating, the main thread may not have the same values that are used
     // to draw.
     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 clipRect.
     bool is_clipped;
 
     // The layer whose coordinate space this layer draws into. This can be
     // either the same layer (m_drawProperties.render_target == this) or an
     // ancestor of this layer.
     LayerType* render_target;
 
     // The surface that this layer and its subtree would contribute to.
     scoped_ptr<RenderSurfaceType> render_surface;
 
     // This rect is in the layer's content space.
     gfx::Rect visible_content_rect;
 
     // In target surface space, the rect that encloses the clipped, drawable
     // content of the layer.
     gfx::Rect drawable_content_rect;
 
     // In target surface space, the original rect that clipped this
     // layer. This value is used to avoid unnecessarily changing GL scissor
     // state.
     gfx::Rect clip_rect;
 };
 
 }  // namespace cc
 
 #endif  // CC_DRAW_PROPERTIES_H_