SkCachingPixelRef to use SkImageGenerator

src/lazy/SkCachingPixelRef.h

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkCachingPixelRef_DEFINED
 #define SkCachingPixelRef_DEFINED
 
-#include "SkImage.h"
+#include "SkImageInfo.h"
+#include "SkImageGenerator.h"
 #include "SkPixelRef.h"
 
 class SkColorTable;
 
 /**
  *  PixelRef which defers decoding until SkBitmap::lockPixels() is
  *  called.  Caches the decoded images in the global
  *  SkScaledImageCache.  When the pixels are unlocked, this cache may
  *  or be destroyed before the next lock.  If so, onLockPixels will
  *  attempt to re-decode.
  *
- *  Decoding is handled by the pure-virtual functions onDecodeInfo()
- *  and onDecodePixels().  Subclasses of this class need only provide
- *  those two functions.
+ *  Decoding is handled by the SkImageGenerator
  */
 class SkCachingPixelRef : public SkPixelRef {
 public:
-    SkCachingPixelRef();
-    virtual ~SkCachingPixelRef();
+    /**
+     *  Takes ownership of SkImageGenerator.  If this method fails for
+     *  whatever reason, it will return false and immediatetely delete
+     *  the generator.  If it succeeds, it will modify destination
+     *  bitmap.
+     *
+     *  If Install fails or when the SkCachingPixelRef that is
+     *  installed into destination is destroyed, it will call
+     *  SkDELETE() on the generator.  Therefore, generator should be
+     *  allocated with SkNEW() or SkNEW_ARGS().
+     */
+    static bool Install(SkImageGenerator* gen, SkBitmap* dst);
 
 protected:
+    virtual ~SkCachingPixelRef();
     virtual void* onLockPixels(SkColorTable** colorTable) SK_OVERRIDE;
     virtual void onUnlockPixels() SK_OVERRIDE;
     virtual bool onLockPixelsAreWritable() const SK_OVERRIDE { return false; }
-    virtual bool onImplementsDecodeInto() SK_OVERRIDE  { return true; }
-    virtual bool onDecodeInto(int pow2, SkBitmap*) SK_OVERRIDE;
 
-    /**
-     *  Configure the supplied bitmap for this pixelRef, based on
-     *  information provided by onDecodeInfo().  Does not set the
-     *  bitmap's pixelRef. */
-    bool configure(SkBitmap* bitmap);
-
-    /**
-     *  Cache info from onDecodeInfo(). Returns false on failure.
-     */
-    bool getInfo(SkImageInfo* info);
-
-    /**
-     *  Return some information about the pixels, allowing this class
-     *  to allocate pixels.  @return false if anything goes wrong.
-     */
-    virtual bool onDecodeInfo(SkImageInfo* info) = 0;
-    /**
-     *  Decode into the given pixels, a block of memory of size
-     *  (info.fHeight - 1) * rowBytes + (info.fWidth * bytesPerPixel)
-     *
-     *  @param info Should be identical to the info returned by
-     *         onDecodeInfo so that the implementation can confirm
-     *         that the caller knows what it is asking for (config,
-     *         size).  Thiscontract also allows the caller to specify
-     *         different output-configs, which the implementation can
-     *         decide to support or not.
-     *
-     *  @return false if anything goes wrong.
-     */
-    virtual bool onDecodePixels(const SkImageInfo& info,
-                                void* pixels,
-                                size_t rowBytes) = 0;
+    virtual SkData* onRefEncodedData() SK_OVERRIDE {
+        return fImageGenerator->refEncodedData();
+    }
+    // No need to flatten this object. When flattening an SkBitmap,
+    // SkOrderedWriteBuffer will check the encoded data and write that
+    // instead.
+    // Future implementations of SkFlattenableWriteBuffer will need to
+    // special case for onRefEncodedData as well.
+    SK_DECLARE_UNFLATTENABLE_OBJECT()
 
 private:
-    bool                        fErrorInDecoding;
-    void*                       fScaledCacheId;
-    SkImageInfo                 fInfo;
+    SkImageGenerator* const fImageGenerator;
+    bool                    fErrorInDecoding;
+    void*                   fScaledCacheId;
+    const SkImageInfo       fInfo;
+    const size_t            fRowBytes;
 
+    SkCachingPixelRef(SkImageGenerator* imageGenerator,
+                      const SkImageInfo& info,
+                      size_t rowBytes);
     typedef SkPixelRef INHERITED;
 };
 
 #endif  // SkCachingPixelRef_DEFINED
+