skia2/include/images/SkImageRef.h

106 lines
3.6 KiB
C++

/*
* Copyright 2008 The Android Open Source Project
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef SkImageRef_DEFINED
#define SkImageRef_DEFINED
#include "SkPixelRef.h"
#include "SkBitmap.h"
#include "SkImageDecoder.h"
#include "SkString.h"
class SkImageRefPool;
class SkStreamRewindable;
// define this to enable dumping whenever we add/remove/purge an imageref
//#define DUMP_IMAGEREF_LIFECYCLE
class SkImageRef : public SkPixelRef {
public:
/** Create a new imageref from a stream. NOTE: the stream is not copied, but
since it may be accessed from another thread, the caller must ensure
that this imageref is the only owner of the stream. i.e. - sole
ownership of the stream object is transferred to this imageref object.
@param stream The stream containing the encoded image data. This may be
retained (by calling ref()), so the caller should not
explicitly delete it.
@param config The preferred config of the decoded bitmap.
@param sampleSize Requested sampleSize for decoding. Defaults to 1.
*/
SkImageRef(SkStreamRewindable*, SkBitmap::Config config, int sampleSize = 1,
SkBaseMutex* mutex = NULL);
virtual ~SkImageRef();
/** this value is passed onto the decoder. Default is true
*/
void setDitherImage(bool dither) { fDoDither = dither; }
/** Return true if the image can be decoded. If so, and bitmap is non-null,
call its setConfig() with the corresponding values, but explicitly will
not set its pixels or colortable. Use SkPixelRef::lockPixels() for that.
If there has been an error decoding the bitmap, this will return false
and ignore the bitmap parameter.
*/
bool getInfo(SkBitmap* bm);
/** Return true if the image can be decoded and is opaque. Calling this
method will decode and set the pixels in the specified bitmap and
sets the isOpaque flag.
*/
bool isOpaque(SkBitmap* bm);
SkImageDecoderFactory* getDecoderFactory() const { return fFactory; }
// returns the factory parameter
SkImageDecoderFactory* setDecoderFactory(SkImageDecoderFactory*);
protected:
/** Override if you want to install a custom allocator.
When this is called we will have already acquired the mutex!
*/
virtual bool onDecode(SkImageDecoder* codec, SkStreamRewindable*, SkBitmap*,
SkBitmap::Config, SkImageDecoder::Mode);
/* Overrides from SkPixelRef
When these are called, we will have already acquired the mutex!
*/
virtual void* onLockPixels(SkColorTable**);
// override this in your subclass to clean up when we're unlocking pixels
virtual void onUnlockPixels() {}
SkImageRef(SkFlattenableReadBuffer&, SkBaseMutex* mutex = NULL);
virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
SkBitmap fBitmap;
private:
SkStreamRewindable* setStream(SkStreamRewindable*);
// called with mutex already held. returns true if the bitmap is in the
// requested state (or further, i.e. has pixels)
bool prepareBitmap(SkImageDecoder::Mode);
SkImageDecoderFactory* fFactory; // may be null
SkStreamRewindable* fStream;
SkBitmap::Config fConfig;
int fSampleSize;
bool fDoDither;
bool fErrorInDecoding;
friend class SkImageRefPool;
SkImageRef* fPrev, *fNext;
size_t ramUsed() const;
typedef SkPixelRef INHERITED;
};
#endif