Adds kind-of-live thumbnail generation for a potential tab switcher.

chrome/browser/renderer_host/backing_store.h

 // Copyright (c) 2006-2008 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.
 
 #ifndef CHROME_BROWSER_RENDERER_HOST_BACKING_STORE_H_
 #define CHROME_BROWSER_RENDERER_HOST_BACKING_STORE_H_
 
 #include "base/basictypes.h"
 #include "base/gfx/rect.h"
 #include "base/gfx/size.h"
 #include "base/process.h"
 #include "build/build_config.h"
 #include "chrome/common/mru_cache.h"
 
 #if defined(OS_WIN)
 #include <windows.h>
 #elif defined(OS_MACOSX)
 #include "skia/ext/platform_canvas.h"
 #elif defined(OS_LINUX)
 #include "chrome/common/x11_util.h"
 #endif
 
 class RenderWidgetHost;
+class SkBitmap;
 class TransportDIB;
 
 // BackingStore ----------------------------------------------------------------
 
 // Represents a backing store for the pixels in a RenderWidgetHost.
 class BackingStore {
  public:
 #if defined(OS_WIN) || defined(OS_MACOSX)
-  explicit BackingStore(const gfx::Size& size);
+  BackingStore(RenderWidgetHost* widget, const gfx::Size& size);
 #elif defined(OS_LINUX)
-  // Create a backing store on the X server.
-  //   size: the size of the server-side pixmap
-  //   x_connection: the display to target
-  //   depth: the depth of the X window which will be drawn into
-  //   visual: An Xlib Visual describing the format of the target window
-  //   root_window: The X id of the root window
-  //   use_render: if true, the X server supports Xrender
-  //   use_shared_memory: if true, the X server is local
-  BackingStore(const gfx::Size& size, Display* x_connection, int depth,
-               void* visual, XID root_window, bool use_render,
-               bool use_shared_memory);
+  // Create a backing store on the X server. The visual is an Xlib Visual
+  // describing the format of the target window and the depth is the color
+  // depth of the X window which will be drawn into.
+  BackingStore(RenderWidgetHost* widget,
+               const gfx::Size& size,
+               void* visual,
+               int depth);
+
   // This is for unittesting only. An object constructed using this constructor
   // will silently ignore all paints
-  explicit BackingStore(const gfx::Size& size);
+  BackingStore(RenderWidgetHost* widget, const gfx::Size& size);
 #endif
   ~BackingStore();
 
+  RenderWidgetHost* render_widget_host() const { return render_widget_host_; }
   const gfx::Size& size() { return size_; }
 
 #if defined(OS_WIN)
   HDC hdc() { return hdc_; }
+
 #elif defined(OS_MACOSX)
   skia::PlatformCanvas* canvas() { return &canvas_; }
+
 #elif defined(OS_LINUX)
   // Copy from the server-side backing store to the target window
   //   display: the display of the backing store and target window
   //   damage: the area to copy
   //   target: the X id of the target window
   void ShowRect(const gfx::Rect& damage, XID target);
 #endif
 
   // Paints the bitmap from the renderer onto the backing store.
   void PaintRect(base::ProcessHandle process,
                  TransportDIB* bitmap,
                  const gfx::Rect& bitmap_rect);
 
   // Scrolls the given rect in the backing store, replacing the given region
   // identified by |bitmap_rect| by the bitmap in the file identified by the
   // given file handle.
   void ScrollRect(base::ProcessHandle process,
                   TransportDIB* bitmap, const gfx::Rect& bitmap_rect,
                   int dx, int dy,
                   const gfx::Rect& clip_rect,
                   const gfx::Size& view_size);
 
  private:
+  // The owner of this backing store.
+  RenderWidgetHost* render_widget_host_;
+
   // The size of the backing store.
   gfx::Size size_;
 
 #if defined(OS_WIN)
 
   // The backing store dc.
   HDC hdc_;
   // Handle to the backing store dib.
   HANDLE backing_store_dib_;
   // Handle to the original bitmap in the dc.
@@ skipping 26 matching lines @@
   // This is the RENDER picture pointing at |pixmap_|.
   XID picture_;
   // This is a default graphic context, used in XCopyArea
   void* pixmap_gc_;
 #endif
 
   DISALLOW_COPY_AND_ASSIGN(BackingStore);
 };
 
 #endif  // CHROME_BROWSER_RENDERER_HOST_BACKING_STORE_H_