Select theme resources from ResourceBundle at requested scale factor.

ui/base/resource/resource_bundle.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 UI_BASE_RESOURCE_RESOURCE_BUNDLE_H_
 #define UI_BASE_RESOURCE_RESOURCE_BUNDLE_H_
 #pragma once
 
 #include "build/build_config.h"
 
@@ skipping 112 matching lines @@
   gfx::Image& GetNativeImageNamed(int resource_id, ImageRTL rtl);
 
   // Same as GetNativeImageNamed() except that RTL is not enabled.
   gfx::Image& GetNativeImageNamed(int resource_id);
 
   // Loads the raw bytes of a data resource into |bytes|,
   // without doing any processing or interpretation of
   // the resource. Returns whether we successfully read the resource.
   base::RefCountedStaticMemory* LoadDataResourceBytes(int resource_id) const;
 
+  // Loads and returns the raw bytes of an image data resource nearest the
+  // target scale factor without doing any processing or interpretation of the
+  // resource. Returns a RefCountedStaticMemory pointer to the image bytes on
+  // success or NULL on failure to locate the resource.
+  base::RefCountedStaticMemory* LoadImageResourceBytes(

[sail, 2012/05/09 16:09:41]

Instead of adding additional APIs we should just add the scale factor parameter
to the existing API.

Otherwise the ResourceBundle API becomes huge and hard to manage.

[flackr, 2012/05/09 19:57:01]

We could do this but the scale factor doesn't make sense for non-image resources
(html, css, js, etc), or locale resources I think. This only applies to image
resources.

[sail, 2012/05/09 20:08:19]

For for loading images we'll now have two APIs, one that has scale factor and
one that doesn't.

Is there a way to assert that the API that doesn't take a scale factor won't be
called for non-image resources?

[flackr, 2012/05/09 20:15:42]

I assume you were tongue twisted and meant to say assert that the API that
doesn't take a scale factor won't be called for image resources :-). We could
add a type to DataPack or have a separate vector for image packs, and only
search image packs from the *Image* functions and only search file packs from
the other functions.

[flackr, 2012/05/09 20:16:53]

Alternately as a low road approach we could assert that only one data pack
contains the requested resource when using the non *Image* functions.

+      int resource_id,
+      float scale_factor) const;
+
+  // Returns the contents of an image resource in a StringPiece nearest the
+  // scale factor |scale_factor| given the resource id.
+  base::StringPiece GetRawImageResource(int resource_id,

[sail, 2012/05/09 16:09:41]

same

+                                        float scale_factor) const;
+
   // Return the contents of a resource in a StringPiece given the resource id.
   base::StringPiece GetRawDataResource(int resource_id) const;
 
   // Get a localized string given a message id.  Returns an empty
   // string if the message_id is not found.
   string16 GetLocalizedString(int message_id);
 
   // Returns the font for the specified style.
   const gfx::Font& GetFont(FontStyle style);
 
@@ skipping 78 matching lines @@
 
   DISALLOW_COPY_AND_ASSIGN(ResourceBundle);
 };
 
 }  // namespace ui
 
 // TODO(beng): Someday, maybe, get rid of this.
 using ui::ResourceBundle;
 
 #endif  // UI_BASE_RESOURCE_RESOURCE_BUNDLE_H_