This class is the smart container for pixel memory, and is used with SkBitmap. More...

#include <SkPixelRef.h>

Inheritance diagram for SkPixelRef:

Classes
struct	GenIDChangeListener

struct	LockRec
	To access the actual pixels of a pixelref, it must be "locked". More...

struct	LockRequest

struct	LockResult

Public Member Functions
	SkPixelRef (const SkImageInfo &)

const SkImageInfo &	info () const

void *	pixels () const
	Return the pixel memory returned from lockPixels, or null if the lockCount is 0.

SkColorTable *	colorTable () const
	Return the current colorTable (if any) if pixels are locked, or null.

size_t	rowBytes () const

bool	isLocked () const

int	getLockCount () const

bool	lockPixels ()
	Call to access the pixel memory. More...

bool	lockPixels (LockRec *rec)
	Call to access the pixel memory. More...

void	unlockPixels ()
	Call to balanace a previous call to lockPixels(). More...

bool	lockPixelsAreWritable () const
	Some bitmaps can return a copy of their pixels for lockPixels(), but that copy, if modified, will not be pushed back. More...

uint32_t	getGenerationID () const
	Returns a non-zero, unique value corresponding to the pixels in this pixelref. More...

void	notifyPixelsChanged ()
	Call this if you have changed the contents of the pixels. More...

void	changeAlphaType (SkAlphaType at)
	Change the info's AlphaType. More...

bool	isImmutable () const
	Returns true if this pixelref is marked as immutable, meaning that the contents of its pixels will not change for the lifetime of the pixelref.

void	setImmutable ()
	Marks this pixelref is immutable, meaning that the contents of its pixels will not change for the lifetime of the pixelref. More...

const char *	getURI () const
	Return the optional URI string associated with this pixelref. More...

void	setURI (const char uri[])
	Copy a URI string to this pixelref, or clear the URI if the uri is null.

void	setURI (const char uri[], size_t len)
	Copy a URI string to this pixelref.

void	setURI (const SkString &uri)
	Assign a URI string to this pixelref.

SkData *	refEncodedData ()
	If the pixelRef has an encoded (i.e. More...

bool	requestLock (const LockRequest &, LockResult *)

bool	queryYUV8 (SkYUVSizeInfo sizeInfo, SkYUVColorSpace colorSpace) const
	If this can efficiently return YUV data, this should return true. More...

bool	getYUV8Planes (const SkYUVSizeInfo &sizeInfo, void *planes[3])
	Returns true on success and false on failure. More...

bool	readPixels (SkBitmap dst, SkColorType colorType, const SkIRect subset=NULL)
	Populates dst with the pixels of this pixelRef, converting them to colorType. More...

void	addGenIDChangeListener (GenIDChangeListener *listener)

void	notifyAddedToCache ()

virtual SkDiscardableMemory *	diagnostic_only_getDiscardable () const

bool	isLazyGenerated () const
	Returns true if the pixels are generated on-the-fly (when required).

Public Member Functions inherited from SkRefCntBase
	SkRefCntBase ()
	Default construct, initializing the reference count to 1.

virtual	~SkRefCntBase ()
	Destruct, asserting that the reference count is 1.

int32_t	getRefCnt () const
	Return the reference count. More...

void	validate () const

bool	unique () const
	May return true if the caller is the only owner. More...

void	ref () const
	Increment the reference count. More...

void	unref () const
	Decrement the reference count. More...

Protected Member Functions
virtual bool	onNewLockPixels (LockRec *)=0
	On success, returns true and fills out the LockRec for the pixels. More...

virtual void	onUnlockPixels ()=0
	Balancing the previous successful call to onNewLockPixels. More...

virtual bool	onLockPixelsAreWritable () const
	Default impl returns true.

virtual bool	onReadPixels (SkBitmap dst, SkColorType colorType, const SkIRect subsetOrNull)
	For pixelrefs that don't have access to their raw pixels, they may be able to make a copy of them (e.g. More...

virtual SkData *	onRefEncodedData ()

virtual void	onNotifyPixelsChanged ()

virtual bool	onQueryYUV8 (SkYUVSizeInfo , SkYUVColorSpace ) const

virtual bool	onGetYUV8Planes (const SkYUVSizeInfo &, void *[3])

virtual size_t	getAllocatedSizeInBytes () const
	Returns the size (in bytes) of the internally allocated memory. More...

virtual bool	onRequestLock (const LockRequest &, LockResult *)

virtual bool	onIsLazyGenerated () const

SkBaseMutex *	mutex () const
	Return the mutex associated with this pixelref. More...

void	setPreLocked (void , size_t rowBytes, SkColorTable )

Protected Member Functions inherited from SkRefCntBase
void	internal_dispose_restore_refcnt_to_1 () const
	Allow subclasses to call this if they've overridden internal_dispose so they can reset fRefCnt before the destructor is called or if they choose not to call the destructor (e.g. More...

Private Types
enum	{ kMutable, kTemporarilyImmutable, kImmutable }

typedef SkRefCnt	INHERITED

Private Member Functions
bool	lockPixelsInsideMutex ()

bool	genIDIsUnique () const

void	needsNewGenID ()

void	callGenIDChangeListeners ()

void	setTemporarilyImmutable ()

void	restoreMutability ()

bool	isPreLocked () const

void	cloneGenID (const SkPixelRef &)

void	setImmutableWithID (uint32_t genID)

Private Attributes
SkMutex	fMutex

const SkImageInfo	fInfo

LockRec	fRec

int	fLockCount

SkAtomic< uint32_t >	fTaggedGenID

SkTDArray< GenIDChangeListener * >	fGenIDChangeListeners

SkString	fURI

SkAtomic< bool >	fAddedToCache

enum SkPixelRef:: { ... }	fMutability

bool	fPreLocked

Friends
class	SkSurface_Raster

class	SkImage_Raster

class	SkSpecialImage_Raster

class	SkBitmap

class	SkImage_Gpu

class	SkImageCacherator

class	SkSpecialImage_Gpu

Detailed Description

This class is the smart container for pixel memory, and is used with SkBitmap.

A pixelref is installed into a bitmap, and then the bitmap can access the actual pixel memory by calling lockPixels/unlockPixels.

This class can be shared/accessed between multiple threads.

Member Function Documentation

void SkPixelRef::changeAlphaType ( SkAlphaType at )

Change the info's AlphaType.

Note that this does not automatically invalidate the generation ID. If the pixel values themselves have changed, then you must explicitly call notifyPixelsChanged() as well.

virtual size_t SkPixelRef::getAllocatedSizeInBytes ( ) const

protectedvirtual

Returns the size (in bytes) of the internally allocated memory.

This should be implemented in all serializable SkPixelRef derived classes. SkBitmap::fPixelRefOffset + SkBitmap::getSafeSize() should never overflow this value, otherwise the rendering code may attempt to read memory out of bounds.

Returns: default impl returns 0.

Reimplemented in SkMallocPixelRef.

uint32_t SkPixelRef::getGenerationID ( ) const

Returns a non-zero, unique value corresponding to the pixels in this pixelref.

Each time the pixels are changed (and notifyPixelsChanged is called), a different generation ID will be returned.

const char* SkPixelRef::getURI ( ) const

inline

Return the optional URI string associated with this pixelref.

May be null.

bool SkPixelRef::getYUV8Planes	(	const SkYUVSizeInfo &	sizeInfo,
		void *	planes[3]
	)

inline

Returns true on success and false on failure.

Copies YUV data into the provided YUV planes.

Parameters

sizeInfo	Needs to exactly match the values returned by the query, except the WidthBytes may be larger than the recommendation (but not smaller).
planes	Memory for each of the Y, U, and V planes.

bool SkPixelRef::lockPixels ( )

Call to access the pixel memory.

Return true on success. Balance this with a call to unlockPixels().

bool SkPixelRef::lockPixels ( LockRec * rec )

Call to access the pixel memory.

On success, return true and fill out the specified rec. On failure, return false and ignore the rec parameter. Balance this with a call to unlockPixels().

bool SkPixelRef::lockPixelsAreWritable ( ) const

Some bitmaps can return a copy of their pixels for lockPixels(), but that copy, if modified, will not be pushed back.

These bitmaps should not be used as targets for a raster device/canvas (since all pixels modifications will be lost when unlockPixels() is called.)

SkBaseMutex* SkPixelRef::mutex ( ) const

inlineprotected

Return the mutex associated with this pixelref.

This value is assigned in the constructor, and cannot change during the lifetime of the object.

void SkPixelRef::notifyPixelsChanged ( )

Call this if you have changed the contents of the pixels.

This will in- turn cause a different generation ID value to be returned from getGenerationID().

virtual bool SkPixelRef::onNewLockPixels ( LockRec * )

protectedpure virtual

On success, returns true and fills out the LockRec for the pixels.

On failure returns false and ignores the LockRec parameter.

The caller will have already acquired a mutex for thread safety, so this method need not do that.

Implemented in SkMallocPixelRef.

virtual bool SkPixelRef::onReadPixels	(	SkBitmap *	dst,
		SkColorType	colorType,
		const SkIRect *	subsetOrNull
	)

protectedvirtual

For pixelrefs that don't have access to their raw pixels, they may be able to make a copy of them (e.g.

if the pixels are on the GPU).

The base class implementation returns false;

virtual void SkPixelRef::onUnlockPixels ( )

protectedpure virtual

Balancing the previous successful call to onNewLockPixels.

The locked pixel address will no longer be referenced, so the subclass is free to move or discard that memory.

The caller will have already acquired a mutex for thread safety, so this method need not do that.

Implemented in SkMallocPixelRef.

bool SkPixelRef::queryYUV8	(	SkYUVSizeInfo *	sizeInfo,
		SkYUVColorSpace *	colorSpace
	)		const

inline

If this can efficiently return YUV data, this should return true.

Otherwise this returns false and does not modify any of the parameters.

Parameters

sizeInfo	Output parameter indicating the sizes and required allocation widths of the Y, U, and V planes.
colorSpace	Output parameter.

bool SkPixelRef::readPixels	(	SkBitmap *	dst,
		SkColorType	colorType,
		const SkIRect *	subset = `NULL`
	)

Populates dst with the pixels of this pixelRef, converting them to colorType.

SkData* SkPixelRef::refEncodedData ( )

inline

If the pixelRef has an encoded (i.e.

compressed) representation, return a ref to its data. If the pixelRef is uncompressed or otherwise does not have this form, return NULL.

If non-null is returned, the caller is responsible for calling unref() on the data when it is finished.

void SkPixelRef::setImmutable ( )

Marks this pixelref is immutable, meaning that the contents of its pixels will not change for the lifetime of the pixelref.

This state can be set on a pixelref, but it cannot be cleared once it is set.

void SkPixelRef::unlockPixels ( )

Call to balanace a previous call to lockPixels().

Returns the pixels (or null) after the unlock. NOTE: lock calls can be nested, but the matching number of unlock calls must be made in order to free the memory (if the subclass implements caching/deferred-decoding.)

The documentation for this class was generated from the following file:

include/core/SkPixelRef.h

Classes

Public Member Functions

Protected Member Functions

Private Types

Private Member Functions

Private Attributes

Friends

Detailed Description

Member Function Documentation