Refactor CopyTexture method determination

gpu/command_buffer/service/gles2_cmd_decoder.cc

Index: gpu/command_buffer/service/gles2_cmd_decoder.cc
diff --git a/gpu/command_buffer/service/gles2_cmd_decoder.cc b/gpu/command_buffer/service/gles2_cmd_decoder.cc
index 46620828f85d7d7c261a207988eae4ecfe5f2ea0..a47aa446d0697a85b4155464f49f966b9aa6e8e7 100644
--- a/gpu/command_buffer/service/gles2_cmd_decoder.cc
+++ b/gpu/command_buffer/service/gles2_cmd_decoder.cc
@@ -2030,14 +2030,19 @@ class GLES2DecoderImpl : public GLES2Decoder, public ErrorStateClient {
                                            TextureRef* source_texture_ref,
                                            TextureRef* dest_texture_ref);
   bool CanUseCopyTextureCHROMIUMInternalFormat(GLenum dest_internal_format);
-  CopyTextureMethod ValidateCopyTextureCHROMIUMInternalFormats(
-      const char* function_name,
-      GLint source_level,
-      GLenum source_internal_format,
-      GLenum source_type,
-      GLenum dest_target,
-      GLint dest_level,
-      GLenum dest_internal_format);
+  bool ValidateCopyTextureCHROMIUMInternalFormats(const char* function_name,
+                                                  GLenum source_internal_format,
+                                                  GLenum dest_internal_format);
+  CopyTextureMethod getCopyTextureCHROMIUMMethod(GLenum source_target,
+                                                 GLint source_level,
+                                                 GLenum source_internal_format,
+                                                 GLenum source_type,
+                                                 GLenum dest_target,
+                                                 GLint dest_level,
+                                                 GLenum dest_internal_format,
+                                                 bool flip_y,
+                                                 bool premultiply_alpha,
+                                                 bool unpremultiply_alpha);
   bool ValidateCompressedCopyTextureCHROMIUM(const char* function_name,
                                              TextureRef* source_texture_ref,
                                              TextureRef* dest_texture_ref);
@@ -16309,13 +16314,9 @@ bool GLES2DecoderImpl::CanUseCopyTextureCHROMIUMInternalFormat(
   }
 }
 
-CopyTextureMethod GLES2DecoderImpl::ValidateCopyTextureCHROMIUMInternalFormats(
+bool GLES2DecoderImpl::ValidateCopyTextureCHROMIUMInternalFormats(
     const char* function_name,
-    GLint source_level,
     GLenum source_internal_format,
-    GLenum source_type,
-    GLenum dest_target,
-    GLint dest_level,
     GLenum dest_internal_format) {
   bool valid_dest_format = false;
   // TODO(qiankun.miao@intel.com): ALPHA, LUMINANCE and LUMINANCE_ALPHA formats
@@ -16393,16 +16394,31 @@ CopyTextureMethod GLES2DecoderImpl::ValidateCopyTextureCHROMIUMInternalFormats(
         GLES2Util::GetStringEnum(source_internal_format);
     LOCAL_SET_GL_ERROR(GL_INVALID_OPERATION, function_name,
                        msg.c_str());
-    return NOT_COPYABLE;
+    return false;
   }
   if (!valid_dest_format) {
     std::string msg = "invalid dest internal format " +
         GLES2Util::GetStringEnum(dest_internal_format);
     LOCAL_SET_GL_ERROR(GL_INVALID_OPERATION, function_name,
                        msg.c_str());
-    return NOT_COPYABLE;
+    return false;
   }
 
+  return true;
+}
+
+CopyTextureMethod GLES2DecoderImpl::getCopyTextureCHROMIUMMethod(
+    GLenum source_target,
+    GLint source_level,
+    GLenum source_internal_format,
+    GLenum source_type,
+    GLenum dest_target,
+    GLint dest_level,
+    GLenum dest_internal_format,
+    bool flip_y,
+    bool premultiply_alpha,
+    bool unpremultiply_alpha) {
+  bool premultiply_alpha_change = premultiply_alpha ^ unpremultiply_alpha;
   bool source_format_color_renderable =
       Texture::ColorRenderable(GetFeatureInfo(), source_internal_format, false);
   bool dest_format_color_renderable =
@@ -16429,8 +16445,10 @@ CopyTextureMethod GLES2DecoderImpl::ValidateCopyTextureCHROMIUMInternalFormats(
   // in ES2 context. DIRECT_DRAW path isn't available for cube map dest texture
   // either due to it may be cube map incomplete. Go to DRAW_AND_COPY path in
   // these cases.
-  if (source_format_color_renderable && copy_tex_image_format_valid &&
-      source_level == 0)
+  if (source_target == GL_TEXTURE_2D &&
+      (dest_target == GL_TEXTURE_2D || dest_target == GL_TEXTURE_CUBE_MAP) &&
+      source_format_color_renderable && copy_tex_image_format_valid &&
+      source_level == 0 && !flip_y && !premultiply_alpha_change)
     return DIRECT_COPY;
   if (dest_format_color_renderable && dest_level == 0 &&
       dest_target != GL_TEXTURE_CUBE_MAP)
@@ -16534,12 +16552,8 @@ void GLES2DecoderImpl::DoCopyTextureCHROMIUM(
     return;
   }
 
-  CopyTextureMethod method = ValidateCopyTextureCHROMIUMInternalFormats(
-      kFunctionName, source_level, source_internal_format, source_type,
-      dest_binding_target, dest_level, internal_format);
-  // INVALID_OPERATION is already generated by
-  // ValidateCopyTextureCHROMIUMInternalFormats.
-  if (method == NOT_COPYABLE) {
+  if (!ValidateCopyTextureCHROMIUMInternalFormats(
+          kFunctionName, source_internal_format, internal_format)) {
     return;
   }
 
@@ -16669,6 +16683,11 @@ void GLES2DecoderImpl::DoCopyTextureCHROMIUM(
     }
   }
 
+  CopyTextureMethod method = getCopyTextureCHROMIUMMethod(
+      source_target, source_level, source_internal_format, source_type,
+      dest_binding_target, dest_level, internal_format,
+      unpack_flip_y == GL_TRUE, unpack_premultiply_alpha == GL_TRUE,
+      unpack_unmultiply_alpha == GL_TRUE);
   copy_texture_CHROMIUM_->DoCopyTexture(
       this, source_target, source_texture->service_id(), source_level,
       source_internal_format, dest_target, dest_texture->service_id(),
@@ -16786,27 +16805,11 @@ void GLES2DecoderImpl::DoCopySubTextureCHROMIUM(
     return;
   }
 
-  CopyTextureMethod method = ValidateCopyTextureCHROMIUMInternalFormats(
-      kFunctionName, source_level, source_internal_format, source_type,
-      dest_binding_target, dest_level, dest_internal_format);
-  // INVALID_OPERATION is already generated by
-  // ValidateCopyTextureCHROMIUMInternalFormats.
-  if (method == NOT_COPYABLE) {
+  if (!ValidateCopyTextureCHROMIUMInternalFormats(
+          kFunctionName, source_internal_format, dest_internal_format)) {
     return;
   }
 
-#if defined(OS_CHROMEOS) && defined(ARCH_CPU_X86_FAMILY)
-  // glDrawArrays is faster than glCopyTexSubImage2D on IA Mesa driver,
-  // although opposite in Android.
-  // TODO(dshwang): After Mesa fixes this issue, remove this hack.
-  // https://bugs.freedesktop.org/show_bug.cgi?id=98478, crbug.com/535198.
-  if (Texture::ColorRenderable(GetFeatureInfo(), dest_internal_format,
-                               dest_texture->IsImmutable()) &&
-      method == DIRECT_COPY) {
-    method = DIRECT_DRAW;
-  }
-#endif
-
   if (feature_info_->feature_flags().desktop_srgb_support) {
     bool enable_framebuffer_srgb =
         GLES2Util::GetColorEncodingFromInternalFormat(source_internal_format) ==
@@ -16892,6 +16895,24 @@ void GLES2DecoderImpl::DoCopySubTextureCHROMIUM(
       return;
     }
   }
+
+  CopyTextureMethod method = getCopyTextureCHROMIUMMethod(
+      source_target, source_level, source_internal_format, source_type,
+      dest_binding_target, dest_level, dest_internal_format,
+      unpack_flip_y == GL_TRUE, unpack_premultiply_alpha == GL_TRUE,
+      unpack_unmultiply_alpha == GL_TRUE);
+#if defined(OS_CHROMEOS) && defined(ARCH_CPU_X86_FAMILY)
+  // glDrawArrays is faster than glCopyTexSubImage2D on IA Mesa driver,
+  // although opposite in Android.
+  // TODO(dshwang): After Mesa fixes this issue, remove this hack.
+  // https://bugs.freedesktop.org/show_bug.cgi?id=98478, crbug.com/535198.
+  if (Texture::ColorRenderable(GetFeatureInfo(), dest_internal_format,
+                               dest_texture->IsImmutable()) &&
+      method == DIRECT_COPY) {
+    method = DIRECT_DRAW;
+  }
+#endif
+
   copy_texture_CHROMIUM_->DoCopySubTexture(
       this, source_target, source_texture->service_id(), source_level,
       source_internal_format, dest_target, dest_texture->service_id(),