Refactor CopyTextureCHROMIUM internalformat validation

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 80d7234db1a14a553dffb18d6158a0b66afbb85b..c823faa86045760849505492ca0eb3fc9f753288 100644
--- a/gpu/command_buffer/service/gles2_cmd_decoder.cc
+++ b/gpu/command_buffer/service/gles2_cmd_decoder.cc
@@ -2028,8 +2028,11 @@ class GLES2DecoderImpl : public GLES2Decoder, public ErrorStateClient {
   bool CanUseCopyTextureCHROMIUMInternalFormat(GLenum dest_internal_format);
   CopyTextureMethod ValidateCopyTextureCHROMIUMInternalFormats(
       const char* function_name,
-      TextureRef* source_texture_ref,
       GLint source_level,
+      GLenum source_internal_format,
+      GLenum source_type,
+      GLenum dest_target,
+      GLint dest_level,
       GLenum dest_internal_format);
   bool ValidateCompressedCopyTextureCHROMIUM(const char* function_name,
                                              TextureRef* source_texture_ref,
@@ -16270,15 +16273,12 @@ bool GLES2DecoderImpl::CanUseCopyTextureCHROMIUMInternalFormat(
 
 CopyTextureMethod GLES2DecoderImpl::ValidateCopyTextureCHROMIUMInternalFormats(
     const char* function_name,
-    TextureRef* source_texture_ref,
     GLint source_level,
+    GLenum source_internal_format,
+    GLenum source_type,
+    GLenum dest_target,
+    GLint dest_level,
     GLenum dest_internal_format) {
-  GLenum source_type = 0;
-  GLenum source_internal_format = 0;
-  Texture* source_texture = source_texture_ref->texture();
-  source_texture->GetLevelType(source_texture->target(), source_level,
-                               &source_type, &source_internal_format);
-
   bool valid_dest_format = false;
   // TODO(qiankun.miao@intel.com): ALPHA, LUMINANCE and LUMINANCE_ALPHA formats
   // are not supported on GL core profile. See crbug.com/577144. Enable the
@@ -16372,12 +16372,26 @@ CopyTextureMethod GLES2DecoderImpl::ValidateCopyTextureCHROMIUMInternalFormats(
       dest_internal_format != GL_BGRA8_EXT &&
       ValidateCopyTexFormatHelper(dest_internal_format, source_internal_format,
                                   source_type, &output_error_msg);
-  if (source_format_color_renderable && copy_tex_image_format_valid)
-    return DIRECT_COPY;
 
-  if (dest_format_color_renderable)
+  // TODO(qiankun.miao@intel.com): for WebGL 2.0 or OpenGL ES 3.0, both
+  // DIRECT_DRAW path for dest_level > 0 and DIRECT_COPY path for source_level >
+  // 0 are not available due to a framebuffer completeness bug:
+  // crbug.com/678526. Once the bug is fixed, the limitation for WebGL 2.0 and
+  // OpenGL ES 3.0 can be lifted.
+  // For WebGL 1.0 or OpenGL ES 2.0, DIRECT_DRAW path isn't available for
+  // dest_level > 0 due to level > 0 isn't supported by glFramebufferTexture2D
+  // 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)
+    return DIRECT_COPY;
+  if (dest_format_color_renderable && dest_level == 0 &&
+      dest_target != GL_TEXTURE_CUBE_MAP)
     return DIRECT_DRAW;
 
+  // Draw to a fbo attaching level 0 of an intermediate texture,
+  // then copy from the fbo to dest texture level with glCopyTexImage2D.
   return DRAW_AND_COPY;
 }
 
@@ -16475,31 +16489,14 @@ void GLES2DecoderImpl::DoCopyTextureCHROMIUM(
   }
 
   CopyTextureMethod method = ValidateCopyTextureCHROMIUMInternalFormats(
-      kFunctionName, source_texture_ref, source_level, internal_format);
+      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) {
     return;
   }
 
-  // Draw to a fbo attaching level 0 of an intermediate texture,
-  // then copy from the fbo to dest texture level with glCopyTexImage2D.
-  // For WebGL 1.0 or OpenGL ES 2.0, DIRECT_DRAW path isn't available for
-  // dest_level > 0 due to level > 0 isn't supported by glFramebufferTexture2D
-  // 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.
-  // TODO(qiankun.miao@intel.com): for WebGL 2.0 or OpenGL ES 3.0, both
-  // DIRECT_DRAW path for dest_level > 0 and DIRECT_COPY path for source_level >
-  // 0 are not available due to a framebuffer completeness bug:
-  // crbug.com/678526. Once the bug is fixed, the limitation for WebGL 2.0 and
-  // OpenGL ES 3.0 can be lifted.
-  if (((dest_level > 0 || dest_binding_target == GL_TEXTURE_CUBE_MAP) &&
-       method == DIRECT_DRAW) ||
-      (source_level > 0 && method == DIRECT_COPY)) {
-    method = DRAW_AND_COPY;
-  }
-
   if (feature_info_->feature_flags().desktop_srgb_support) {
     bool enable_framebuffer_srgb =
         GLES2Util::GetColorEncodingFromInternalFormat(source_internal_format) ==
@@ -16744,7 +16741,8 @@ void GLES2DecoderImpl::DoCopySubTextureCHROMIUM(
   }
 
   CopyTextureMethod method = ValidateCopyTextureCHROMIUMInternalFormats(
-      kFunctionName, source_texture_ref, source_level, dest_internal_format);
+      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) {
@@ -16763,24 +16761,6 @@ void GLES2DecoderImpl::DoCopySubTextureCHROMIUM(
   }
 #endif
 
-  // Draw to a fbo attaching level 0 of an intermediate texture,
-  // then copy from the fbo to dest texture level with glCopyTexImage2D.
-  // For WebGL 1.0 or OpenGL ES 2.0, DIRECT_DRAW path isn't available for
-  // dest_level > 0 due to level > 0 isn't supported by glFramebufferTexture2D
-  // 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.
-  // TODO(qiankun.miao@intel.com): for WebGL 2.0 or OpenGL ES 3.0, both
-  // DIRECT_DRAW path for dest_level > 0 and DIRECT_COPY path for source_level >
-  // 0 are not available due to a framebuffer completeness bug:
-  // crbug.com/678526. Once the bug is fixed, the limitation for WebGL 2.0 and
-  // OpenGL ES 3.0 can be lifted.
-  if (((dest_level > 0 || dest_binding_target == GL_TEXTURE_CUBE_MAP) &&
-       method == DIRECT_DRAW) ||
-      (source_level > 0 && method == DIRECT_COPY)) {
-    method = DRAW_AND_COPY;
-  }
-
   if (feature_info_->feature_flags().desktop_srgb_support) {
     bool enable_framebuffer_srgb =
         GLES2Util::GetColorEncodingFromInternalFormat(source_internal_format) ==