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

webkit/gpu/webgraphicscontext3d_in_process_impl.cc

 // 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.
 
 #include "webkit/gpu/webgraphicscontext3d_in_process_impl.h"
 
 #include <string.h>
 
 #include <algorithm>
 #include <string>
@@ skipping 146 matching lines @@
     // and force them to drop their contexts, sending a context lost event if
     // necessary.
     if (webView) webView->mainFrame()->collectGarbage();
 
     gl_surface_ = gfx::GLSurface::CreateOffscreenGLSurface(false,
                                                            gfx::Size(1, 1));
     if (!gl_surface_.get())
       return false;
   }
 
+  // TODO(kbr): This implementation doesn't yet support lost contexts
+  // and therefore can't yet properly support GPU switching.
+  gfx::GpuPreference gpu_preference = gfx::PreferDiscreteGpu;
+
   gl_context_ = gfx::GLContext::CreateGLContext(share_group,
-                                                gl_surface_.get());
+                                                gl_surface_.get(),
+                                                gpu_preference);
   if (!gl_context_.get()) {
     if (!is_gles2_)
       return false;
 
     // Embedded systems have smaller limit on number of GL contexts. Sometimes
     // failure of GL context creation is because of existing GL contexts
     // referenced by JavaScript garbages. Collect garbage and try again.
     // TODO: Besides this solution, kbr@chromium.org suggested: upon receiving
     // a page unload event, iterate down any live WebGraphicsContext3D instances
     // and force them to drop their contexts, sending a context lost event if
     // necessary.
     if (webView) webView->mainFrame()->collectGarbage();
 
     gl_context_ = gfx::GLContext::CreateGLContext(share_group,
-                                                  gl_surface_.get());
+                                                  gl_surface_.get(),
+                                                  gpu_preference);
     if (!gl_context_.get())
       return false;
   }
 
   attributes_ = attributes;
 
   // FIXME: for the moment we disable multisampling for the compositor.
   // It actually works in this implementation, but there are a few
   // considerations. First, we likely want to reduce the fuzziness in
   // these tests as much as possible because we want to run pixel tests.
@@ skipping 1470 matching lines @@
   if (length > 1) {
     entry->translated_source.reset(new char[length]);
     ShGetObjectCode(compiler, entry->translated_source.get());
   }
   entry->is_valid = true;
   return true;
 }
 
 }  // namespace gpu
 }  // namespace webkit