cc: Support anti-aliasing for solid color layers.

cc/solid_color_draw_quad.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_SOLID_COLOR_DRAW_QUAD_H_
 #define CC_SOLID_COLOR_DRAW_QUAD_H_
 
 #include "base/memory/scoped_ptr.h"
 #include "cc/cc_export.h"
 #include "cc/draw_quad.h"
 #include "third_party/skia/include/core/SkColor.h"
 
 namespace cc {
 
 class CC_EXPORT SolidColorDrawQuad : public DrawQuad {
  public:
   static scoped_ptr<SolidColorDrawQuad> Create();
 
   void SetNew(const SharedQuadState* shared_quad_state,
               gfx::Rect rect,
-              SkColor color);
+              SkColor color,
+              bool left_edge_aa,
+              bool top_edge_aa,
+              bool right_edge_aa,
+              bool bottom_edge_aa);
 
   void SetAll(const SharedQuadState* shared_quad_state,
               gfx::Rect rect,
               gfx::Rect opaque_rect,
               gfx::Rect visible_rect,
               bool needs_blending,
-              SkColor color);
+              SkColor color,
+              bool left_edge_aa,
+              bool top_edge_aa,
+              bool right_edge_aa,
+              bool bottom_edge_aa);
 
   SkColor color;
 
+  // TODO(danakj): Stick the data used to compute these things in the quad

[danakj, 2012/12/21 20:50:18]

Maybe we can address this TODO at the same time?

It seems like the data could/should go in shared_quad_state, then all the solid
color quad callsites won't need to change in this CL. And the gl_renderer can do
AA for all quad types given the right inputs in the shared_quad_state.

[reveman, 2012/12/21 20:58:05]

hm, not sure I understand. isn't the shared state shared between all tiles?
these aa properties will be different between each tile as they are set based on
if the tile is at the edge of the layer or not.

[danakj, 2012/12/21 22:18:58]

Ah, yes. I guess we need some piece of data on each tile (if it's the edge). But
other data used in the decision could go on the shared_quad_state (maybe it's
all there already, I didn't look at this too hard yet).

[reveman, 2012/12/21 23:33:46]

the only piece of data shared between tiles is:
bool useAA = m_tiler->hasBorderTexels() && !isAxisAlignedInTarget;

which I don't think is necessary. The isAxisAlignedInTarget check is done in
drawTileQuad already so I think we change this into:
DCHECK(m_tiler->hasBorderTexels() || isAxisAlignedInTarget)

+  // instead so the parent compositor can decide to use AA on its own.
+  bool left_edge_aa;
+  bool top_edge_aa;
+  bool right_edge_aa;
+  bool bottom_edge_aa;
+
+  bool IsAntialiased() const {
+    return left_edge_aa || top_edge_aa || right_edge_aa || bottom_edge_aa;
+  }
+
   static const SolidColorDrawQuad* MaterialCast(const DrawQuad*);
  private:
   SolidColorDrawQuad();
 };
 
 }
 
 #endif  // CC_SOLID_COLOR_DRAW_QUAD_H_