Browser side changes for software compositing

content/renderer/render_widget.cc

Index: content/renderer/render_widget.cc
diff --git a/content/renderer/render_widget.cc b/content/renderer/render_widget.cc
index 16872d83246fe385e7d37fd59e0d04bccbd4435d..70808859213bd3687851eeac17bef7e28d0f2961 100644
--- a/content/renderer/render_widget.cc
+++ b/content/renderer/render_widget.cc
@@ -24,7 +24,6 @@
 #include "content/common/view_messages.h"
 #include "content/public/common/content_switches.h"
 #include "content/renderer/gpu/compositor_output_surface.h"
-#include "content/renderer/gpu/compositor_software_output_device_gl_adapter.h"
 #include "content/renderer/gpu/input_handler_manager.h"
 #include "content/renderer/gpu/mailbox_output_surface.h"
 #include "content/renderer/gpu/render_widget_compositor.h"
@@ -57,6 +56,12 @@
 #include "webkit/plugins/npapi/webplugin.h"
 #include "webkit/plugins/ppapi/ppapi_plugin_instance.h"
 
+#if defined(USE_AURA)
+#include "content/renderer/gpu/compositor_software_output_device.h"
+#else
+#include "content/renderer/gpu/compositor_software_output_device_gl_adapter.h"
+#endif  // defined(USE_AURA)
+
 #if defined(OS_POSIX)
 #include "ipc/ipc_channel_posix.h"
 #include "third_party/skia/include/core/SkMallocPixelRef.h"
@@ -555,6 +560,16 @@ bool RenderWidget::ForceCompositingModeEnabled() {
 }
 
 scoped_ptr<cc::OutputSurface> RenderWidget::CreateOutputSurface() {
+  const CommandLine& command_line = *CommandLine::ForCurrentProcess();
+
+#if defined(USE_AURA)

[piman, 2013/04/03 18:31:26]

AURA is really a UI concept, which shouldn't have a place in the renderer.
I don't think we should make a decision here based on the ui side. If anything,
because we don't ship any platform with the kEnableSoftwareCompositingGLAdapter
flag, nor ever planning to do so, so I'd say let's just remove the
CompositorSoftwareOutputDeviceGLAdapter, with its flag, and add a new
--enable-software-compositing flag, that would always do the
CompositorSoftwareOutputDevice.

The advantage is that we can make it work for <webview> too, and possibly, in
time, on other platforms if we desire.

[slavi, 2013/04/03 21:38:22]

Done. 

I'll rename the flag in a separate CL that only concerns flags.

+  if (command_line.HasSwitch(switches::kEnableSoftwareCompositingGLAdapter)) {
+      return scoped_ptr<cc::OutputSurface>(
+          new CompositorOutputSurface(routing_id(), NULL,
+              new CompositorSoftwareOutputDevice()));
+  }
+#endif  // defined(USE_AURA)
+
   // Explicitly disable antialiasing for the compositor. As of the time of
   // this writing, the only platform that supported antialiasing for the
   // compositor was Mac OS X, because the on-screen OpenGL context creation
@@ -573,25 +588,23 @@ scoped_ptr<cc::OutputSurface> RenderWidget::CreateOutputSurface() {
   if (!context)
     return scoped_ptr<cc::OutputSurface>();
 
-  const CommandLine& command_line = *CommandLine::ForCurrentProcess();
+#if !defined(USE_AURA)
   if (command_line.HasSwitch(switches::kEnableSoftwareCompositingGLAdapter)) {
-      // In the absence of a software-based delegating renderer, use this
-      // stopgap adapter class to present the software renderer output using a
-      // 3d context.
       return scoped_ptr<cc::OutputSurface>(
           new CompositorOutputSurface(routing_id(), NULL,
               new CompositorSoftwareOutputDeviceGLAdapter(context)));
-  } else {
-      bool composite_to_mailbox =
-          command_line.HasSwitch(cc::switches::kCompositeToMailbox);
-      DCHECK(!composite_to_mailbox || command_line.HasSwitch(
-          cc::switches::kEnableCompositorFrameMessage));
-      // No swap throttling yet when compositing on the main thread.
-      DCHECK(!composite_to_mailbox || is_threaded_compositing_enabled_);
-      return scoped_ptr<cc::OutputSurface>(composite_to_mailbox ?
-          new MailboxOutputSurface(routing_id(), context, NULL) :
-              new CompositorOutputSurface(routing_id(), context, NULL));
   }
+#endif  // !defined(USE_AURA)
+
+  bool composite_to_mailbox =
+      command_line.HasSwitch(cc::switches::kCompositeToMailbox);
+  DCHECK(!composite_to_mailbox || command_line.HasSwitch(
+      cc::switches::kEnableCompositorFrameMessage));
+  // No swap throttling yet when compositing on the main thread.
+  DCHECK(!composite_to_mailbox || is_threaded_compositing_enabled_);
+  return scoped_ptr<cc::OutputSurface>(composite_to_mailbox ?
+      new MailboxOutputSurface(routing_id(), context, NULL) :
+          new CompositorOutputSurface(routing_id(), context, NULL));
 }
 
 void RenderWidget::OnViewContextSwapBuffersAborted() {