mac content shell drt: Hook up a dummy image transport

content/common/gpu/image_transport_surface_mac.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 "content/common/gpu/image_transport_surface.h"
 
 #include "base/mac/scoped_cftyperef.h"
 #include "base/memory/scoped_ptr.h"
 #include "content/common/gpu/gpu_messages.h"
 #include "content/common/gpu/texture_image_transport_surface.h"
+#include "content/shell/shell_switches.h"

[jochen (gone - plz use gerrit), 2013/02/26 14:12:07]

why do you need this?

[Nico, 2013/02/26 14:26:52]

Removed.

 #include "ui/gfx/native_widget_types.h"
 #include "ui/gl/gl_bindings.h"
 #include "ui/gl/gl_context.h"
 #include "ui/gl/gl_implementation.h"
 #include "ui/gl/gl_surface_cgl.h"
+#include "ui/gl/gl_surface_osmesa.h"
 #include "ui/surface/io_surface_support_mac.h"
 
 namespace content {
 namespace {
 
 // IOSurface dimensions will be rounded up to a multiple of this value in order
 // to reduce memory thrashing during resize. This must be a power of 2.
 const uint32 kIOSurfaceDimensionRoundup = 64;
 
 int RoundUpSurfaceDimension(int number) {
@@ skipping 377 matching lines @@
     UnrefIOSurface();
     return;
   }
 
   glFlush();
 
   glBindTexture(target, previous_texture_id);
   // The FBO remains bound for this GL context.
 }
 
+// A subclass of GLSurfaceOSMesa that doesn't print an error message when
+// SwapBuffers() is called.
+class DRTSurfaceOSMesa : public gfx::GLSurfaceOSMesa {
+ public:
+  // Size doesn't matter, the surface is resized to the right size later.
+  explicit DRTSurfaceOSMesa()

[jochen (gone - plz use gerrit), 2013/02/26 14:12:07]

no explicit

[Nico, 2013/02/26 14:26:52]

Done.

+      : GLSurfaceOSMesa(GL_RGBA, gfx::Size(1, 1)) {}
+
+  // Implement a subset of GLSurface.
+  virtual bool SwapBuffers() OVERRIDE;
+
+ private:
+  ~DRTSurfaceOSMesa() {}

[jochen (gone - plz use gerrit), 2013/02/26 14:12:07]

virtual

[Nico, 2013/02/26 14:26:52]

Done.

+  DISALLOW_COPY_AND_ASSIGN(DRTSurfaceOSMesa);
+};
+
+bool DRTSurfaceOSMesa::SwapBuffers() {
+  return true;
+}
+
+bool g_allow_os_mesa = false;
+
 }  // namespace
 
 // static
 scoped_refptr<gfx::GLSurface> ImageTransportSurface::CreateSurface(
     GpuChannelManager* manager,
     GpuCommandBufferStub* stub,
     const gfx::GLSurfaceHandle& surface_handle) {
   scoped_refptr<gfx::GLSurface> surface;
   if (surface_handle.transport_type == gfx::TEXTURE_TRANSPORT) {
      surface = new TextureImageTransportSurface(manager, stub, surface_handle);
   } else {
     DCHECK(surface_handle.transport_type == gfx::NATIVE_TRANSPORT);
     IOSurfaceSupport* io_surface_support = IOSurfaceSupport::Initialize();
 
     switch (gfx::GetGLImplementation()) {
       case gfx::kGLImplementationDesktopGL:
       case gfx::kGLImplementationAppleGL:
         if (!io_surface_support) {
           DLOG(WARNING) << "No IOSurface support";
           return NULL;
         } else {
           surface = new IOSurfaceImageTransportSurface(
               manager, stub, surface_handle.handle);
         }
         break;
       default:
-        NOTREACHED();
-        return NULL;
+        // Content shell in DRT mode spins up a gpu process which needs an
+        // image transport surface, but that surface isn't used to read pixel
+        // baselines. So this is mostly a dummy surface.
+        if (g_allow_os_mesa) {
+          surface = new DRTSurfaceOSMesa();

[jochen (gone - plz use gerrit), 2013/02/26 14:12:07]

does it matter that it prints the error message? Can't we just use new
GLsurfaceOSMesa() here?

[Nico, 2013/02/26 14:26:52]

Sure it matters, random error log spew is confusing.

(Also, GLSurfaceOSMesa() returns false from its swap method, which causes
context lost events all the time.)

+        } else {
+          NOTREACHED();
+          return NULL;
+        }
     }
   }
   if (surface->Initialize())
     return surface;
   else
     return NULL;
 }
 
+// static
+void ImageTransportSurface::SetAllowOSMesa(bool allow) {
+  g_allow_os_mesa = allow;
+}
+
 }  // namespace content