skia2/include/images/SkImageRef.h
2009-09-24 17:21:05 +00:00

108 lines
3.7 KiB
C++

/*
* Copyright (C) 2008 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef SkImageRef_DEFINED
#define SkImageRef_DEFINED
#include "SkPixelRef.h"
#include "SkBitmap.h"
#include "SkImageDecoder.h"
#include "SkString.h"
class SkImageRefPool;
class SkStream;
// 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(SkStream*, SkBitmap::Config config, int sampleSize = 1);
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);
SkImageDecoderFactory* getDecoderFactory() const { return fFactory; }
// returns the factory parameter
SkImageDecoderFactory* setDecoderFactory(SkImageDecoderFactory*);
// overrides
virtual void flatten(SkFlattenableWriteBuffer&) const;
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, SkStream*, 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&);
SkBitmap fBitmap;
private:
SkStream* setStream(SkStream*);
// 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
SkStream* fStream;
SkBitmap::Config fConfig;
int fSampleSize;
bool fDoDither;
bool fErrorInDecoding;
friend class SkImageRefPool;
SkImageRef* fPrev, *fNext;
size_t ramUsed() const;
typedef SkPixelRef INHERITED;
};
#endif