Support dynamic switching between integrated and discrete GPUs on Mac OS X.

content/browser/renderer_host/accelerated_plugin_view_mac.mm

 // Copyright (c) 2011 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.
 
 #import "content/browser/renderer_host/accelerated_plugin_view_mac.h"
 
+#include <vector>
+
 #include "base/command_line.h"
 #include "base/debug/trace_event.h"
 #include "content/browser/browser_thread.h"
 #include "content/browser/renderer_host/render_widget_host_view_mac.h"
+#include "ui/gfx/gl/gl_context.h"
 #include "ui/gfx/gl/gl_switches.h"
 #include "ui/gfx/scoped_ns_graphics_context_save_gstate_mac.h"
 
 @implementation AcceleratedPluginView
 
 - (void)drawView {
   CHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   TRACE_EVENT0("browser", "AcceleratedPluginViewMac::drawView");
 
   if (renderWidgetHostView_) {
     // TODO(thakis): Pixel or view coordinates for size?
     renderWidgetHostView_->DrawAcceleratedSurfaceInstance(
         cglContext_, pluginHandle_, [super frame].size);
   }
 
   CGLFlushDrawable(cglContext_);
   CGLSetCurrentContext(0);
 }
 
 - (id)initWithRenderWidgetHostViewMac:(RenderWidgetHostViewMac*)r
                          pluginHandle:(gfx::PluginWindowHandle)pluginHandle {
   if ((self = [super initWithFrame:NSZeroRect])) {
     renderWidgetHostView_ = r;
     pluginHandle_ = pluginHandle;
 
     [self setAutoresizingMask:NSViewMaxXMargin|NSViewMinYMargin];
 
-    NSOpenGLPixelFormatAttribute attributes[] =
-        { NSOpenGLPFAAccelerated, NSOpenGLPFADoubleBuffer, 0};
+    std::vector<NSOpenGLPixelFormatAttribute> attributes;
+    attributes.push_back(NSOpenGLPFAAccelerated);
+    attributes.push_back(NSOpenGLPFADoubleBuffer);
+    if (gfx::GLContext::SupportsDualGpus())
+      attributes.push_back(NSOpenGLPFAAllowOfflineRenderers);
+    attributes.push_back(0);
 
     // TODO(zmo): remove the diagnostic error messages once we figure out the
     // cause of the failure and a fix.
 
     glPixelFormat_.reset([[NSOpenGLPixelFormat alloc]
-        initWithAttributes:attributes]);
+        initWithAttributes:&attributes.front()]);
     if (!glPixelFormat_)
       LOG(ERROR) << "NSOpenGLPixelFormat initWithAttributes failed";
 
     glContext_.reset([[NSOpenGLContext alloc] initWithFormat:glPixelFormat_
                                                 shareContext:nil]);
     if (!glContext_)
       LOG(ERROR) << "NSOpenGLContext initWithFormat failed";
 
     // We "punch a hole" in the window, and have the WindowServer render the
     // OpenGL surface underneath so we can draw over it.
@@ skipping 191 matching lines @@
   return YES;
 }
 
 - (void)viewDidMoveToSuperview {
   TRACE_EVENT0("browser", "AcceleratedPluginView::viewDidMoveToSuperview");
   if (![self superview])
     [self onRenderWidgetHostViewGone];
 }
 @end