CMAA: Avoid DCHECK failure for unsupported internalformats

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_copy_texture_chromium.h"
 #include "gpu/command_buffer/service/gles2_cmd_decoder.h"
 #include "gpu/command_buffer/service/texture_manager.h"
 #include "ui/gl/gl_context.h"
 #include "ui/gl/gl_gl_api_implementation.h"
 #include "ui/gl/gl_version_info.h"
 
 #define SHADER(Src) #Src
 
+namespace {
+
+bool CanUseCopyTextureCHROMIUM(GLenum internal_format) {
+  switch (internal_format) {
+    case GL_RGB:
+    case GL_RGBA:
+    case GL_RGB8:
+    case GL_RGBA8:
+    case GL_BGRA_EXT:
+    case GL_BGRA8_EXT:
+    case GL_SRGB_EXT:
+    case GL_SRGB_ALPHA_EXT:
+    case GL_R8:
+    case GL_R8UI:
+    case GL_RG8:
+    case GL_RG8UI:
+    case GL_SRGB8:
+    case GL_RGB565:
+    case GL_RGB8UI:
+    case GL_SRGB8_ALPHA8:
+    case GL_RGB5_A1:
+    case GL_RGBA4:
+    case GL_RGBA8UI:
+    case GL_RGB9_E5:
+    case GL_R16F:
+    case GL_R32F:
+    case GL_RG16F:
+    case GL_RG32F:
+    case GL_RGB16F:
+    case GL_RGB32F:
+    case GL_RGBA16F:
+    case GL_RGBA32F:
+    case GL_R11F_G11F_B10F:
+      return true;
+    default:
+      return false;
+  }
+}
+
+}  // namespace
+
 namespace gpu {
 namespace gles2 {
 
 ApplyFramebufferAttachmentCMAAINTELResourceManager::
     ApplyFramebufferAttachmentCMAAINTELResourceManager()
     : initialized_(false),
       textures_initialized_(false),
       is_in_gamma_correct_mode_(false),
       supports_usampler_(true),
       supports_r8_image_(true),
@@ skipping 219 matching lines @@
       TextureRef* texture =
           texture_manager->GetTexture(attachment->object_name());
       const bool rgba_immutable =
           texture->texture()->IsImmutable() &&
           TextureManager::ExtractFormatFromStorageFormat(internal_format) ==
               GL_RGBA;
       const bool do_copy = !rgba_immutable;
 
       // CMAA Effect
       if (do_copy) {
+        if (!CanUseCopyTextureCHROMIUM(internal_format)) {
+          DLOG(ERROR) << "Apply CMAA on framebuffer with attachment in "

[qiankun, 2017/02/13 08:52:25]

I am not sure if the format limitation should be handled as a gl error, for
example, INVALID_OPERATION. There is no such format limitation in the extension
spec:
https://www.khronos.org/registry/OpenGL/extensions/INTEL/INTEL_framebuffer_CM....
So, it may be issue of this implementation in chrome. Dongseong, can you confirm
this?

[Zhenyao Mo, 2017/02/13 18:36:17]

I think for Chrome to generate an INVALID_OPERATION in such situation is fine -
much better than failing silently (DLOG usually isn't very useful)

[qiankun, 2017/02/14 08:08:17]

Generete INVALID_OPERATION for such invalid situation.

+                      << GLES2Util::GetStringEnum(internal_format)
+                      << " internalformat.";
+          return;
+        }
         ApplyCMAAEffectTexture(source_texture, rgba8_texture_, do_copy);
 
         // Source format for DoCopySubTexture is always GL_RGBA8.
         CopyTextureMethod method = DIRECT_COPY;
         bool copy_tex_image_format_valid =
             !GLES2Util::IsIntegerFormat(internal_format) &&
             GLES2Util::GetColorEncodingFromInternalFormat(internal_format) !=
                 GL_SRGB &&
             internal_format != GL_BGRA_EXT && internal_format != GL_BGRA8_EXT;
         if (GLES2Util::IsSizedColorFormat(internal_format)) {
@@ skipping 1614 matching lines @@
     \n#endif\n
     \n#if defined DISPLAY_EDGES\n
       DisplayEdges();
     \n#endif\n
     }
   );
 /* clang-format on */
 
 }  // namespace gles2
 }  // namespace gpu