Check gl version before querying GL_MAX_SAMPLES

gpu/config/gpu_info_collector.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/config/gpu_info_collector.h"
 
 #include <string>
 #include <vector>
 
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/metrics/sparse_histogram.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_piece.h"
 #include "base/strings/string_split.h"
 #include "base/trace_event/trace_event.h"
 #include "ui/gl/gl_bindings.h"
 #include "ui/gl/gl_context.h"
 #include "ui/gl/gl_implementation.h"
 #include "ui/gl/gl_surface.h"
+#include "ui/gl/gl_version_info.h"
 
 namespace {
 
 scoped_refptr<gfx::GLSurface> InitializeGLSurface() {
   scoped_refptr<gfx::GLSurface> surface(
       gfx::GLSurface::CreateOffscreenGLSurface(gfx::Size()));
   if (!surface.get()) {
     LOG(ERROR) << "gfx::GLContext::CreateOffscreenGLSurface failed";
     return NULL;
   }
@@ skipping 64 matching lines @@
   if (!context.get()) {
     LOG(ERROR) << "Could not create context for info collection.";
     return kCollectInfoFatalFailure;
   }
 
   gpu_info->gl_renderer = GetGLString(GL_RENDERER);
   gpu_info->gl_vendor = GetGLString(GL_VENDOR);
   gpu_info->gl_extensions = gfx::GetGLExtensionsFromCurrentContext();
   gpu_info->gl_version = GetGLString(GL_VERSION);
   std::string glsl_version_string = GetGLString(GL_SHADING_LANGUAGE_VERSION);
+
+  gfx::GLVersionInfo gl_info(gpu_info->gl_version.c_str(),
+                             gpu_info->gl_renderer.c_str(),
+                             gpu_info->gl_extensions.c_str());
   GLint max_samples = 0;
-  glGetIntegerv(GL_MAX_SAMPLES, &max_samples);
+  if (gl_info.IsAtLeastGL(3, 0) || gl_info.IsAtLeastGLES(3, 0))

[Zhenyao Mo, 2015/11/25 18:09:25]

It's more complicated.  You also need to consider the extension support, say,
EXT_multisampled_render_to_texture.

+    glGetIntegerv(GL_MAX_SAMPLES, &max_samples);
   gpu_info->max_msaa_samples = base::IntToString(max_samples);
   UMA_HISTOGRAM_SPARSE_SLOWLY("GPU.MaxMSAASampleCount", max_samples);
 
   gfx::GLWindowSystemBindingInfo window_system_binding_info;
   if (GetGLWindowSystemBindingInfo(&window_system_binding_info)) {
     gpu_info->gl_ws_vendor = window_system_binding_info.vendor;
     gpu_info->gl_ws_version = window_system_binding_info.version;
     gpu_info->gl_ws_extensions = window_system_binding_info.extensions;
     gpu_info->direct_rendering = window_system_binding_info.direct_rendering;
   }
@@ skipping 51 matching lines @@
   basic_gpu_info->video_decode_accelerator_supported_profiles =
       context_gpu_info.video_decode_accelerator_supported_profiles;
   basic_gpu_info->video_encode_accelerator_supported_profiles =
       context_gpu_info.video_encode_accelerator_supported_profiles;
   basic_gpu_info->jpeg_decode_accelerator_supported =
       context_gpu_info.jpeg_decode_accelerator_supported;
 }
 
 }  // namespace gpu