Enable texture readback support for Android

content/public/browser/android/compositor.h

 // 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.
 
 #ifndef CONTENT_PUBLIC_BROWSER_ANDROID_COMPOSITOR_H_
 #define CONTENT_PUBLIC_BROWSER_ANDROID_COMPOSITOR_H_
 
 #include "base/callback.h"
 #include "ui/gfx/native_widget_types.h"
 #include "ui/gfx/rect.h"
@@ skipping 52 matching lines @@
 
   // Generates an OpenGL compressed texture and returns a texture handle.  May
   // return 0 if the current context is lost.
   virtual WebKit::WebGLId GenerateCompressedTexture(gfx::Size& size,
                                                     int data_size,
                                                     void* data) = 0;
 
   // Deletes an OpenGL texture.
   virtual void DeleteTexture(WebKit::WebGLId texture_id) = 0;
 
+  // Grabs a copy of |texture_id| and saves it into |bitmap|.  No scaling is
+  // done.  It is assumed that the texture size matches that of the bitmap.
+  virtual void CopyTextureToBitmap(WebKit::WebGLId texture_id,
+                                   gfx::JavaBitmap& bitmap) = 0;

[no sievers, 2012/10/20 00:42:36]

Do you really need to add this generic interface?
Isn't the one in ContentViewCore enough?

[David Trainor- moved to gerrit, 2012/10/22 08:31:07]

For ContentViewCore#getBitmap it is, but for some of the other delayed capture
work the RWHV might be destroyed, in which case I need a way to grab the bitmap
from a texture.  ContentViewCore has a method to copy and scale the RWHV's
texture to a new one, which I can readback here even if the original one is
gone.

On 2012/10/20 00:42:36, Daniel Sievers wrote:

  protected:
   Compositor() {}
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_ANDROID_COMPOSITOR_H_