skia2/include/images/SkImageRef.h
scroggo@google.com b5571b3324 Change SkImageDecoders to take an SkStreamRewindable.
Only affects factories, static functions that will use the factories,
and subset decoding, which all require rewinding. The decoders
themselves continue to take an SkStream. This is merely documentation
stating which functions will possibly rewind the passed in SkStream.

This is part of the general change to coordinate SkStreams with
Android's streams, which don't necessarily support rewinding in all
cases.

Update callers to use SkStreamRewindable.

BUG=skia:1572
R=bungeman@google.com, reed@google.com

Review URL: https://codereview.chromium.org/23477009

git-svn-id: http://skia.googlecode.com/svn/trunk@11460 2bbb7eff-a529-9590-31e7-b0007b416f81
2013-09-25 21:34:24 +00:00

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