Deserialize pictures with custom image-deserializer

include/core/SkImageDeserializer.h

+/*
+ * Copyright 2016 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef SkImageDeserializer_DEFINED
+#define SkImageDeserializer_DEFINED
+
+#include "SkRefCnt.h"
+
+struct SkIRect;
+class SkData;
+class SkImage;
+
+class SK_API SkImageDeserializer {
+public:
+    virtual ~SkImageDeserializer() {}
+
+    /**
+     *  Given a data containing serialized content, return an SkImage from it.
+     *
+     *  The default implementation is to call SkImage::MakeFromEncoded(...)
+     */
+    virtual sk_sp<SkImage> deserialize(sk_sp<SkData>, const SkIRect* subset);

[mtklein, 2016/08/10 21:48:31]

const sk_sp<SkData>& ?

Passing by value (i.e. always reffing the data) seems like a detail specific to
SkImage::MakeFromEncoded().  We could pretty easily imagine an
SkImageDeserializer that doesn't need to ref the data.

[reed1, 2016/08/10 23:43:19]

Happy to go either way. Will switch to pointer.

+};
+
+#endif