This change adds the apple software renderer as an option on Chrome/Mac. It's enabled by passing...

ui/gfx/gl/gl_surface_cgl.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 "ui/gfx/gl/gl_surface_cgl.h"
 
+#include <OpenGL/CGLRenderers.h>
+
 #include "base/basictypes.h"
 #include "base/logging.h"
 #include "base/mac/mac_util.h"
 #include "ui/gfx/gl/gl_bindings.h"
 #include "ui/gfx/gl/gl_context.h"
+#include "ui/gfx/gl/gl_implementation.h"
 
 namespace gfx {
 
 namespace {
 CGLPixelFormatObj g_pixel_format;
 }
 
 GLSurfaceCGL::GLSurfaceCGL() {
 }
 
 GLSurfaceCGL::~GLSurfaceCGL() {
 }
 
 bool GLSurfaceCGL::InitializeOneOff() {
   static bool initialized = false;
   if (initialized)
     return true;
 
   // This is called from the sandbox warmup code on Mac OS X.
   // GPU-related stuff is very slow without this, probably because
   // the sandbox prevents loading graphics drivers or some such.
   std::vector<CGLPixelFormatAttribute> attribs;
   if (GLContext::SupportsDualGpus()) {
     // Avoid switching to the discrete GPU just for this pixel
     // format selection.
     attribs.push_back(kCGLPFAAllowOfflineRenderers);
   }
+  if (GetGLImplementation() == kGLImplementationAppleGL) {
+    attribs.push_back(kCGLPFARendererID);
+    attribs.push_back(static_cast<CGLPixelFormatAttribute>(
+      kCGLRendererGenericFloatID));
+  }
   attribs.push_back(static_cast<CGLPixelFormatAttribute>(0));
 
   CGLPixelFormatObj format;
   GLint num_pixel_formats;
   if (CGLChoosePixelFormat(&attribs.front(),
                            &format,
                            &num_pixel_formats) != kCGLNoError) {
     LOG(ERROR) << "Error choosing pixel format.";
     return false;
   }
   if (!format) {
     LOG(ERROR) << "format == 0.";
     return false;
   }
   CGLReleasePixelFormat(format);
   DCHECK_NE(num_pixel_formats, 0);
   initialized = true;
   return true;
 }
 
 void* GLSurfaceCGL::GetPixelFormat() {
   return g_pixel_format;
 }
 
 PbufferGLSurfaceCGL::PbufferGLSurfaceCGL(const gfx::Size& size)

[Ken Russell (switch to Gerrit), 2011/12/06 19:23:47]

Can we just delete the PbufferGLSurfaceCGL at this point? Perhaps create a
NullGLSurfaceCGL or similar that's compatible with GLContextCGL? Fine to do this
as a subsequent cleanup but would be nice to do.

[Stephen White, 2011/12/06 19:49:04]

Good idea.

   : size_(size),
     pbuffer_(NULL) {
 }
 
 PbufferGLSurfaceCGL::~PbufferGLSurfaceCGL() {
   Destroy();
 }
 
 bool PbufferGLSurfaceCGL::Initialize() {
   if (CGLCreatePBuffer(size_.width(),
@@ skipping 29 matching lines @@
 
 gfx::Size PbufferGLSurfaceCGL::GetSize() {
   return size_;
 }
 
 void* PbufferGLSurfaceCGL::GetHandle() {
   return pbuffer_;
 }
 
 }  // namespace gfx