Improve performance of dragged tab renderering....

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;
+typedef struct _GdkDrawable GdkDrawable;
 
 // BackingStore ----------------------------------------------------------------
 
 // Represents a backing store for the pixels in a RenderWidgetHost.
 class BackingStore {
  public:
 #if defined(OS_WIN) || defined(OS_MACOSX)
   BackingStore(RenderWidgetHost* widget, const gfx::Size& size);
 #elif defined(OS_LINUX)
   // Create a backing store on the X server. The visual is an Xlib Visual
@@ skipping 32 matching lines @@
   //   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);
 
   // Paints the server-side backing store data to a SkBitmap. On failure, the
   // return bitmap will be isNull().
   SkBitmap PaintRectToBitmap(const gfx::Rect& rect);
 #endif
 
+#if defined(TOOLKIT_GTK)
+  // Paint the backing store into the target's |dest_rect|.
+  void PaintToRect(const gfx::Rect& dest_rect, GdkDrawable* 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,
@@ skipping 45 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_