Support browser side thumbnailing for GPU composited pages on Windows.

content/browser/gpu/gpu_surface_tracker.h

Index: content/browser/gpu/gpu_surface_tracker.h
diff --git a/content/browser/gpu/gpu_surface_tracker.h b/content/browser/gpu/gpu_surface_tracker.h
index 039c9d2b69637972429fae75544258165cbc5ca9..e80200d8de9b101b0b6a24667aedf2cc0543f597 100644
--- a/content/browser/gpu/gpu_surface_tracker.h
+++ b/content/browser/gpu/gpu_surface_tracker.h
@@ -6,13 +6,17 @@
 #define CONTENT_BROWSER_GPU_GPU_SURFACE_TRACKER_H_
 
 #include <map>
+#include <vector>
 
 #include "base/basictypes.h"
+#include "base/memory/scoped_ptr.h"
 #include "base/memory/singleton.h"
 #include "base/synchronization/lock.h"
 #include "ui/gfx/native_widget_types.h"
 #include "ui/gfx/size.h"
 
+class GpuSurfaceReader;
+
 // This class is responsible for managing rendering surfaces exposed to the
 // GPU process. Every surface gets registered to this class, and gets an ID.
 // All calls to and from the GPU process, with the exception of
@@ -24,6 +28,13 @@
 // it is unamibiguously identified.
 class GpuSurfaceTracker {
  public:
+  struct SurfaceInfo {

[apatrick_chromium, 2012/03/07 20:39:37]

If it weren't for GpuSurfaceReader, this could remain private.

[mazda, 2012/03/08 13:14:28]

Done.

+    int renderer_id;
+    int render_widget_id;
+    gfx::AcceleratedWidget native_widget;
+    gfx::GLSurfaceHandle handle;
+  };
+
   // Gets the global instance of the surface tracker.
   static GpuSurfaceTracker* Get() { return GetInstance(); }
 
@@ -58,6 +69,12 @@ class GpuSurfaceTracker {
   // Note: This is an O(log N) lookup.
   gfx::GLSurfaceHandle GetSurfaceHandle(int surface_id);
 
+  // Copies the image data of the the given surface to |out|. The image data
+  // is transformed so that it fits in |size|.
+  bool CopySurface(int surface_id,
+                   const gfx::Size& size,
+                   std::vector<unsigned char>* out);
+
 #if defined(OS_WIN) && !defined(USE_AURA)
   // This is a member of GpuSurfaceTracker because it holds the lock for its
   // duration. This prevents the AcceleratedSurface that it posts to from being
@@ -76,12 +93,6 @@ class GpuSurfaceTracker {
   static GpuSurfaceTracker* GetInstance();
 
  private:
-  struct SurfaceInfo {
-    int renderer_id;
-    int render_widget_id;
-    gfx::AcceleratedWidget native_widget;
-    gfx::GLSurfaceHandle handle;
-  };
   typedef std::map<int, SurfaceInfo> SurfaceMap;
 
   friend struct DefaultSingletonTraits<GpuSurfaceTracker>;
@@ -92,6 +103,7 @@ class GpuSurfaceTracker {
   base::Lock lock_;
   SurfaceMap surface_map_;
   int next_surface_id_;
+  scoped_ptr<GpuSurfaceReader> reader_;
 
   DISALLOW_COPY_AND_ASSIGN(GpuSurfaceTracker);
 };