new image from backend desc

include/core/SkImage.h

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkImage_DEFINED
 #define SkImage_DEFINED
 
@@ skipping 46 matching lines @@
 
     /**
      *  Construct a new SkImage based on the specified encoded data. Returns NULL on failure,
      *  which can mean that the format of the encoded data was not recognized/supported.
      *
      *  Regardless of success or failure, the caller is responsible for managing their ownership
      *  of the data.
      */
     static SkImage* NewFromData(SkData* data);
 
+    /**
+     *  Create a new image from the specified descriptor. Note - the caller is responsible for
+     *  managing the lifetime of the underlying platform texture.
+     *
+     *  Will return NULL if the specified descriptor is unsupported.
+     */
+    static SkImage* NewFromTexture(GrContext*, const GrBackendTextureDesc&,
+                                   SkAlphaType = kPremul_SkAlphaType);
+
+    /**
+     *  Create a new image by copying the pixels from the specified descriptor. No reference is
+     *  kept to the original platform texture.
+     *
+     *  Will return NULL if the specified descriptor is unsupported.
+     */
+    static SkImage* NewFromTextureCopy(GrContext*, const GrBackendTextureDesc&,
+                                       SkAlphaType = kPremul_SkAlphaType);
+
     int width() const { return fWidth; }
     int height() const { return fHeight; }
     uint32_t uniqueID() const { return fUniqueID; }
     virtual bool isOpaque() const { return false; }
 
     /**
      * Return the GrTexture that stores the image pixels. Calling getTexture
      * does not affect the reference count of the GrTexture object.
      * Will return NULL if the image does not use a texture.
      */
@@ skipping 91 matching lines @@
     const int       fWidth;
     const int       fHeight;
     const uint32_t  fUniqueID;
 
     static uint32_t NextUniqueID();
 
     typedef SkRefCnt INHERITED;
 };
 
 #endif