UI Resource Manager

cc/resources/scoped_ui_resource.h

+// Copyright 2013 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 CC_RESOURCES_SCOPED_UI_RESOURCE_H_
+#define CC_RESOURCES_SCOPED_UI_RESOURCE_H_
+
+#include "base/memory/ref_counted.h"
+#include "cc/resources/ui_resource_bitmap.h"
+#include "ui/gfx/size.h"
+
+namespace cc {
+
+class LayerTreeHost;
+typedef int UIResourceId;

[aelias_OOO_until_Jul13, 2013/07/25 23:45:11]

I'm not sure every compiler out there is happy with redefined typedefs and this
can be considered duplicated code anyway, I suggest just including the header.

[powei, 2013/07/26 23:07:27]

Where should this definition live?  It could be in layer_tree_host.h, but then
including layer_tree_host everywhere we want to use UIResourceId does not seem
appropriate.  Should I just make a stub class (ui_resource_manager or
ui_resource_id) that has this definition? 

[aelias_OOO_until_Jul13, 2013/07/26 23:35:31]

ui_resource_client.h seems OK.

+
+class ScopedUIResource : public base::RefCounted<ScopedUIResource> {

[aelias_OOO_until_Jul13, 2013/07/25 23:45:11]

I don't see a reason to refcount this class, please remove this and hold it in a
scoped_ptr<> in ScrollbarLayer instead.

[powei, 2013/07/26 23:07:27]

Done.  Switched back to client-based.

+ public:
+  static scoped_refptr<ScopedUIResource> Create(
+      LayerTreeHost* host,
+      scoped_refptr<UIResourceBitmap> bitmap);
+
+  ~ScopedUIResource() { ClearResource(); }

[aelias_OOO_until_Jul13, 2013/07/25 23:45:11]

This needs to call ReleaseResource, not ClearResource.  This code is leaking the
UIResourceID as it stands.  So you'll need to hold the LayerTreeHost as a
member.

Also, make this non-inline (I think clang will complain).

[powei, 2013/07/26 23:07:27]

Done.

+
+  void ClearResource();
+  void ResetResource(LayerTreeHost* host,

[aelias_OOO_until_Jul13, 2013/07/25 23:45:11]

On second thought, this method isn't needed after all, sorry for suggesting it. 
The user can just create a new ScopedUIResource instead.  It doesn't look like
ClearResource and ReleaseResource are useful either.  Please delete all the
public methods except for id().

[powei, 2013/07/26 23:07:27]

Done.

+                     scoped_refptr<UIResourceBitmap> bitmap);
+  void ReleaseResource(LayerTreeHost* host);
+  UIResourceId id() const { return id_; }
+
+ protected:
+  ScopedUIResource(LayerTreeHost* host, scoped_refptr<UIResourceBitmap> bitmap);
+
+  UIResourceId id_;
+  scoped_refptr<UIResourceBitmap> bitmap_;
+
+ private:
+  scoped_refptr<UIResourceBitmap> GetBitmap(bool resource_lost);
+};
+
+}  // namespace cc
+
+#endif  // CC_RESOURCES_SCOPED_UI_RESOURCE_H_