gpu, cmaa: Don't blend isolated L shape because it's not a closed geometry.

gpu/command_buffer/service/gles2_cmd_apply_framebuffer_attachment_cmaa_intel.cc

 // Copyright 2016 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 "gpu/command_buffer/service/gles2_cmd_apply_framebuffer_attachment_cmaa_intel.h"
 
 #include "base/logging.h"
 #include "gpu/command_buffer/service/framebuffer_manager.h"
 #include "gpu/command_buffer/service/gles2_cmd_decoder.h"
 #include "ui/gl/gl_context.h"
@@ skipping 1548 matching lines @@
                            bool(packedEdgesL & 0x08u) &&
                            bool(packedEdgesT & 0x01u);
           bool large_l3 = (packedEdgesC == (0x04u | 0x08u)) &&
                            bool(packedEdgesR & 0x08u) &&
                            bool(packedEdgesT & 0x04u);
           bool large_l4 = (packedEdgesC == (0x02u | 0x04u)) &&
                            bool(packedEdgesR & 0x02u) &&
                            bool(packedEdgesB & 0x04u);
           if (large_l1 || large_l2 || large_l3 || large_l4)
             continue;
+
+          // Don't blend isolated L shape because it's not a closed geometry.
+          // isolated_l1 isolated_l2 isolated_l3 isolated_l4
+          //   _                                   _
+          //   X|          X|         |X          |X
+          //               ¯¯         ¯¯
+          bool isolated_l1 = (packedEdgesC == (0x01u | 0x02u)) &&
+                           bool((packedEdgesL & 0x02u) == 0x00u) &&

[Zhenyao Mo, 2016/07/05 01:47:27]

I didn't review the original CLs, but chrome doesn't allow c style type cast. 
You will need to do static_cast here (or is it really necessary?

Also, indent is off.

[Zhenyao Mo, 2016/07/05 01:50:39]

Never mind.  Just realized it's shader source, so it doesn't matter. But could
you still fix indent for readability purpose?

[dshwang, 2016/07/05 11:41:26]

Yes, I will apply clang-format.

+                           bool((packedEdgesT & 0x04u) == 0x00u) &&
+                           bool((packedEdgesR & 0x08u) == 0x00u) &&
+                           bool((packedEdgesB & 0x01u) == 0x00u);
+          bool isolated_l2 = (packedEdgesC == (0x01u | 0x08u)) &&
+                           bool((packedEdgesL & 0x08u) == 0x00u) &&
+                           bool((packedEdgesT & 0x01u) == 0x00u) &&
+                           bool((packedEdgesR & 0x02u) == 0x00u) &&
+                           bool((packedEdgesB & 0x04u) == 0x00u);
+          bool isolated_l3 = (packedEdgesC == (0x04u | 0x08u)) &&
+                           bool((packedEdgesL & 0x02u) == 0x00u) &&
+                           bool((packedEdgesT & 0x04u) == 0x00u) &&
+                           bool((packedEdgesR & 0x08u) == 0x00u) &&
+                           bool((packedEdgesB & 0x01u) == 0x00u);
+          bool isolated_l4 = (packedEdgesC == (0x02u | 0x04u)) &&
+                           bool((packedEdgesL & 0x08u) == 0x00u) &&
+                           bool((packedEdgesT & 0x01u) == 0x00u) &&
+                           bool((packedEdgesR & 0x02u) == 0x00u) &&
+                           bool((packedEdgesB & 0x04u) == 0x00u);
+          if (isolated_l1 || isolated_l2 || isolated_l3 || isolated_l4)
+            continue;
         }
 
         // 2.) U-like shape (surrounded with edges from 3 sides)
         if (numberOfEdges == 3.0) {
           // with value of 0.13, the pixel will retain approx 72% of its
           // colour and the remaining 28% will be picked from its 3
           // neighbours (which are unlikely to be blurred too but could be)
           blurCoeff = 0.13;
         }
 
@@ skipping 290 matching lines @@
       \n#ifdef OUT_FBO\n
         outColor = pixel;
       \n#else\n
         imageStore(outTexture, screenPosI, pixel);
       \n#endif\n
       }
     );
 /* clang-format on */
 
 }  // namespace gpu