Proposed SkCanvas API for preLoading textures to VRAM v2.0

include/core/SkPicture.h

Index: include/core/SkPicture.h
===================================================================
--- include/core/SkPicture.h	(revision 13812)
+++ include/core/SkPicture.h	(working copy)
@@ -34,6 +34,27 @@
 public:
     SK_DECLARE_INST_COUNT(SkPicture)
 
+    // AccelData provides a base class for device-specific acceleration
+    // data. It is added to the picture via a call to a device's optimize 
+    // method.
+    class AccelData : public SkRefCnt {
+    public:
+        typedef uint8_t Domain;
+        typedef uint32_t Key;
+
+        AccelData(Key key) : fKey(key) { }
+
+        const Key& getKey() const { return fKey; }
+
+        // This entry point allows user's to get a unique domain prefix
+        // for their keys
+        static Domain GenerateDomain();
+    private:
+        Key fKey;
+
+        typedef SkRefCnt INHERITED;
+    };
+
     /** The constructor prepares the picture to record.
         @param width the width of the virtual device the picture records.
         @param height the height of the virtual device the picture records.
@@ -44,6 +65,18 @@
     */
     SkPicture(const SkPicture& src);
 
+    /**  PRIVATE / EXPERIMENTAL -- do not call */
+    void EXPERIMENTAL_addAccelData(const AccelData* data) { 
+        SkRefCnt_SafeAssign(fAccelData, data); 
+    }
+    /**  PRIVATE / EXPERIMENTAL -- do not call */
+    const AccelData* EXPERIMENTAL_getAccelData(AccelData::Key key) const { 
+        if (NULL != fAccelData && fAccelData->getKey() == key) {
+            return fAccelData; 
+        }
+        return NULL;
+    }
+
     /**
      *  Function signature defining a function that sets up an SkBitmap from encoded data. On
      *  success, the SkBitmap should have its Config, width, height, rowBytes and pixelref set.
@@ -262,9 +295,10 @@
     // fPlayback, fRecord, fWidth & fHeight are protected to allow derived classes to
     // install their own SkPicturePlayback-derived players,SkPictureRecord-derived
     // recorders and set the picture size
-    SkPicturePlayback* fPlayback;
-    SkPictureRecord* fRecord;
-    int fWidth, fHeight;
+    SkPicturePlayback*    fPlayback;
+    SkPictureRecord*      fRecord;
+    int                   fWidth, fHeight;
+    const AccelData*      fAccelData;
 
     // Create a new SkPicture from an existing SkPicturePlayback. Ref count of
     // playback is unchanged.