1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/gfx/skia/trunk/src/lazy/SkCachingPixelRef.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,69 @@
1.4 +/*
1.5 + * Copyright 2013 Google Inc.
1.6 + *
1.7 + * Use of this source code is governed by a BSD-style license that can be
1.8 + * found in the LICENSE file.
1.9 + */
1.10 +
1.11 +#ifndef SkCachingPixelRef_DEFINED
1.12 +#define SkCachingPixelRef_DEFINED
1.13 +
1.14 +#include "SkImageInfo.h"
1.15 +#include "SkImageGenerator.h"
1.16 +#include "SkPixelRef.h"
1.17 +
1.18 +class SkColorTable;
1.19 +
1.20 +/**
1.21 + * PixelRef which defers decoding until SkBitmap::lockPixels() is
1.22 + * called. Caches the decoded images in the global
1.23 + * SkScaledImageCache. When the pixels are unlocked, this cache may
1.24 + * or be destroyed before the next lock. If so, onLockPixels will
1.25 + * attempt to re-decode.
1.26 + *
1.27 + * Decoding is handled by the SkImageGenerator
1.28 + */
1.29 +class SkCachingPixelRef : public SkPixelRef {
1.30 +public:
1.31 + SK_DECLARE_INST_COUNT(SkCachingPixelRef)
1.32 + /**
1.33 + * Takes ownership of SkImageGenerator. If this method fails for
1.34 + * whatever reason, it will return false and immediatetely delete
1.35 + * the generator. If it succeeds, it will modify destination
1.36 + * bitmap.
1.37 + *
1.38 + * If Install fails or when the SkCachingPixelRef that is
1.39 + * installed into destination is destroyed, it will call
1.40 + * SkDELETE() on the generator. Therefore, generator should be
1.41 + * allocated with SkNEW() or SkNEW_ARGS().
1.42 + */
1.43 + static bool Install(SkImageGenerator* gen, SkBitmap* dst);
1.44 +
1.45 +protected:
1.46 + virtual ~SkCachingPixelRef();
1.47 + virtual bool onNewLockPixels(LockRec*) SK_OVERRIDE;
1.48 + virtual void onUnlockPixels() SK_OVERRIDE;
1.49 + virtual bool onLockPixelsAreWritable() const SK_OVERRIDE { return false; }
1.50 +
1.51 + virtual SkData* onRefEncodedData() SK_OVERRIDE {
1.52 + return fImageGenerator->refEncodedData();
1.53 + }
1.54 + // No need to flatten this object. When flattening an SkBitmap,
1.55 + // SkWriteBuffer will check the encoded data and write that
1.56 + // instead.
1.57 + // Future implementations of SkWriteBuffer will need to
1.58 + // special case for onRefEncodedData as well.
1.59 + SK_DECLARE_UNFLATTENABLE_OBJECT()
1.60 +
1.61 +private:
1.62 + SkImageGenerator* const fImageGenerator;
1.63 + bool fErrorInDecoding;
1.64 + void* fScaledCacheId;
1.65 + const size_t fRowBytes;
1.66 +
1.67 + SkCachingPixelRef(const SkImageInfo&, SkImageGenerator*, size_t rowBytes);
1.68 +
1.69 + typedef SkPixelRef INHERITED;
1.70 +};
1.71 +
1.72 +#endif // SkCachingPixelRef_DEFINED
