[Command buffer] blitFramebuffer should not disable scissor test

gpu/command_buffer/service/gles2_cmd_decoder.cc

 // Copyright (c) 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.
 
 #include "gpu/command_buffer/service/gles2_cmd_decoder.h"
 
 #include <limits.h>
 #include <stddef.h>
 #include <stdint.h>
 #include <stdio.h>
@@ skipping 7704 matching lines @@
       ((mask & GL_COLOR_BUFFER_BIT) != 0);
   if (!enable_srgb ||
       read_buffer_samples > 0 ||
       !feature_info_->feature_flags().desktop_srgb_support ||
       gl_version_info().IsAtLeastGL(4, 4) ||
       (gl_version_info().IsAtLeastGL(4, 2) && encode_srgb_only)) {
     if (enable_srgb && gl_version_info().IsAtLeastGL(4, 2)) {
       state_.EnableDisableFramebufferSRGB(enable_srgb);
     }
 
-    // TODO(yunchao) Need to revisit here. In GLES spec, blitFramebuffer
-    // should do scissor test per fragment operation.
-    state_.SetDeviceCapabilityState(GL_SCISSOR_TEST, false);

[Zhenyao Mo, 2016/09/23 18:35:21]

You can only remove this conditionally.  The CHROMIUM extension does say
BlitFramebuffer isn't affected by scissor (probably just for coding convenience
at the time, now it's a messy situation).

So only remove this if it's ES3 contexts and then stop advertise that extension
in FeatureInfo when it's ES3.

     BlitFramebufferHelper(
         srcX0, srcY0, srcX1, srcY1, dstX0, dstY0, dstX1, dstY1, mask, filter);
-    state_.SetDeviceCapabilityState(GL_SCISSOR_TEST,
-                                  state_.enable_flags.scissor_test);
     return;
   }
 
   // emulate srgb for desktop core profile when GL version < 4.4
   // TODO(yunchao): Need to handle this situation:
   // There are multiple draw buffers. Some of them are srgb images.
   // The others are not.
   state_.EnableDisableFramebufferSRGB(true);
   if (!InitializeSRGBConverter(func_name)) {
     return;
   }
   GLenum src_format =
       TextureManager::ExtractFormatFromStorageFormat(src_internal_format);
   srgb_converter_->Blit(this, srcX0, srcY0, srcX1, srcY1,
                         dstX0, dstY0, dstX1, dstY1,
                         mask, filter,
                         GetBoundReadFramebufferSize(),
                         GetBoundReadFramebufferServiceId(),
                         src_internal_format, src_format, src_type,
                         GetBoundDrawFramebufferServiceId(),
-                        read_buffer_has_srgb, draw_buffers_has_srgb);
+                        read_buffer_has_srgb, draw_buffers_has_srgb,
+                        state_.enable_flags.scissor_test);
 }
 
 bool GLES2DecoderImpl::InitializeSRGBConverter(
     const char* function_name) {
   if (!srgb_converter_.get()) {
     LOCAL_COPY_REAL_GL_ERRORS_TO_WRAPPER(function_name);
     srgb_converter_.reset(
         new SRGBConverter(feature_info_.get()));
     srgb_converter_->InitializeSRGBConverter(this);
     if (LOCAL_PEEK_GL_ERROR(function_name) != GL_NO_ERROR) {
@@ skipping 10314 matching lines @@
 }
 
 // Include the auto-generated part of this file. We split this because it means
 // we can easily edit the non-auto generated parts right here in this file
 // instead of having to edit some template or the code generator.
 #include "base/macros.h"
 #include "gpu/command_buffer/service/gles2_cmd_decoder_autogen.h"
 
 }  // namespace gles2
 }  // namespace gpu