SkPixmap provides a utility to pair SkImageInfo with pixels and row bytes. More...

#include <SkPixmap.h>

Public Member Functions
	SkPixmap ()
	Creates an empty SkPixmap without pixels, with kUnknown_SkColorType, with kUnknown_SkAlphaType, and with a width and height of zero. More...

	SkPixmap (const SkImageInfo &info, const void *addr, size_t rowBytes)
	Creates SkPixmap from info width, height, SkAlphaType, and SkColorType. More...

void	reset ()
	Sets width, height, row bytes to zero; pixel address to nullptr; SkColorType to kUnknown_SkColorType; and SkAlphaType to kUnknown_SkAlphaType. More...

void	reset (const SkImageInfo &info, const void *addr, size_t rowBytes)
	Sets width, height, SkAlphaType, and SkColorType from info. More...

void	setColorSpace (sk_sp< SkColorSpace > colorSpace)
	Changes SkColorSpace in SkImageInfo; preserves width, height, SkAlphaType, and SkColorType in SkImage, and leaves pixel address and row bytes unchanged. More...

bool	reset (const SkMask &mask)
	Deprecated. More...

bool	extractSubset (SkPixmap *subset, const SkIRect &area) const
	Sets subset width, height, pixel address to intersection of SkPixmap with area, if intersection is not empty; and return true. More...

const SkImageInfo &	info () const
	Returns width, height, SkAlphaType, SkColorType, and SkColorSpace. More...

size_t	rowBytes () const
	Returns row bytes, the interval from one pixel row to the next. More...

const void *	addr () const
	Returns pixel address, the base address corresponding to the pixel origin. More...

int	width () const
	Returns pixel count in each pixel row. More...

int	height () const
	Returns pixel row count. More...

SkISize	dimensions () const
	Return the dimensions of the pixmap (from its ImageInfo) More...

SkColorType	colorType () const

SkAlphaType	alphaType () const

SkColorSpace *	colorSpace () const
	Returns SkColorSpace, the range of colors, associated with SkImageInfo. More...

sk_sp< SkColorSpace >	refColorSpace () const
	Returns smart pointer to SkColorSpace, the range of colors, associated with SkImageInfo. More...

bool	isOpaque () const
	Returns true if SkAlphaType is kOpaque_SkAlphaType. More...

SkIRect	bounds () const
	Returns SkIRect { 0, 0, width(), height() }. More...

int	rowBytesAsPixels () const
	Returns number of pixels that fit on row. More...

int	shiftPerPixel () const
	Returns bit shift converting row bytes to row pixels. More...

size_t	computeByteSize () const
	Returns minimum memory required for pixel storage. More...

bool	computeIsOpaque () const
	Returns true if all pixels are opaque. More...

SkColor	getColor (int x, int y) const
	Returns pixel at (x, y) as unpremultiplied color. More...

SkColor4f	getColor4f (int x, int y) const
	Returns pixel at (x, y) as unpremultiplied color as an SkColor4f. More...

float	getAlphaf (int x, int y) const
	Look up the pixel at (x,y) and return its alpha component, normalized to [0..1]. More...

const void *	addr (int x, int y) const
	Returns readable pixel address at (x, y). More...

const uint8_t *	addr8 () const
	Returns readable base pixel address. More...

const uint16_t *	addr16 () const
	Returns readable base pixel address. More...

const uint32_t *	addr32 () const
	Returns readable base pixel address. More...

const uint64_t *	addr64 () const
	Returns readable base pixel address. More...

const uint16_t *	addrF16 () const
	Returns readable base pixel address. More...

const uint8_t *	addr8 (int x, int y) const
	Returns readable pixel address at (x, y). More...

const uint16_t *	addr16 (int x, int y) const
	Returns readable pixel address at (x, y). More...

const uint32_t *	addr32 (int x, int y) const
	Returns readable pixel address at (x, y). More...

const uint64_t *	addr64 (int x, int y) const
	Returns readable pixel address at (x, y). More...

const uint16_t *	addrF16 (int x, int y) const
	Returns readable pixel address at (x, y). More...

void *	writable_addr () const
	Returns writable base pixel address. More...

void *	writable_addr (int x, int y) const
	Returns writable pixel address at (x, y). More...

uint8_t *	writable_addr8 (int x, int y) const
	Returns writable pixel address at (x, y). More...

uint16_t *	writable_addr16 (int x, int y) const
	Returns writable_addr pixel address at (x, y). More...

uint32_t *	writable_addr32 (int x, int y) const
	Returns writable pixel address at (x, y). More...

uint64_t *	writable_addr64 (int x, int y) const
	Returns writable pixel address at (x, y). More...

uint16_t *	writable_addrF16 (int x, int y) const
	Returns writable pixel address at (x, y). More...

bool	readPixels (const SkImageInfo &dstInfo, void *dstPixels, size_t dstRowBytes) const
	Copies a SkRect of pixels to dstPixels. More...

bool	readPixels (const SkImageInfo &dstInfo, void *dstPixels, size_t dstRowBytes, int srcX, int srcY) const
	Copies a SkRect of pixels to dstPixels. More...

bool	readPixels (const SkPixmap &dst, int srcX, int srcY) const
	Copies a SkRect of pixels to dst. More...

bool	readPixels (const SkPixmap &dst) const
	Copies pixels inside bounds() to dst. More...

bool	scalePixels (const SkPixmap &dst, const SkSamplingOptions &) const
	Copies SkBitmap to dst, scaling pixels to fit dst.width() and dst.height(), and converting pixels to match dst.colorType() and dst.alphaType(). More...

bool	erase (SkColor color, const SkIRect &subset) const
	Writes color to pixels bounded by subset; returns true on success. More...

bool	erase (SkColor color) const
	Writes color to pixels inside bounds(); returns true on success. More...

bool	erase (const SkColor4f &color, const SkIRect *subset=nullptr) const
	Writes color to pixels bounded by subset; returns true on success. More...

Detailed Description

SkPixmap provides a utility to pair SkImageInfo with pixels and row bytes.

SkPixmap is a low level class which provides convenience functions to access raster destinations. SkCanvas can not draw SkPixmap, nor does SkPixmap provide a direct drawing destination.

Use SkBitmap to draw pixels referenced by SkPixmap; use SkSurface to draw into pixels referenced by SkPixmap.

SkPixmap does not try to manage the lifetime of the pixel memory. Use SkPixelRef to manage pixel memory; SkPixelRef is safe across threads.

Constructor & Destructor Documentation

◆ SkPixmap() [1/2]

SkPixmap::SkPixmap ( )

inline

Creates an empty SkPixmap without pixels, with kUnknown_SkColorType, with kUnknown_SkAlphaType, and with a width and height of zero.

Use reset() to associate pixels, SkColorType, SkAlphaType, width, and height after SkPixmap has been created.

Returns: empty SkPixmap

◆ SkPixmap() [2/2]

SkPixmap::SkPixmap	(	const SkImageInfo &	info,
		const void *	addr,
		size_t	rowBytes
	)

inline

Creates SkPixmap from info width, height, SkAlphaType, and SkColorType.

addr points to pixels, or nullptr. rowBytes should be info.width() times info.bytesPerPixel(), or larger.

No parameter checking is performed; it is up to the caller to ensure that addr and rowBytes agree with info.

The memory lifetime of pixels is managed by the caller. When SkPixmap goes out of scope, addr is unaffected.

SkPixmap may be later modified by reset() to change its size, pixel type, or storage.

Parameters

info	width, height, SkAlphaType, SkColorType of SkImageInfo
addr	pointer to pixels allocated by caller; may be nullptr
rowBytes	size of one row of addr; width times pixel size, or larger

Returns: initialized SkPixmap

Member Function Documentation

◆ addr() [1/2]

const void* SkPixmap::addr ( ) const

inline

Returns pixel address, the base address corresponding to the pixel origin.

It is up to the SkPixmap creator to ensure that pixel address is a useful value.

Returns: pixel address

◆ addr() [2/2]

const void* SkPixmap::addr	(	int	x,
		int	y
	)		const

inline

Returns readable pixel address at (x, y).

Returns nullptr if SkPixelRef is nullptr.

Input is not validated: out of bounds values of x or y trigger an assert() if built with SK_DEBUG defined. Returns nullptr if SkColorType is kUnknown_SkColorType.

Performs a lookup of pixel size; for better performance, call one of: addr8, addr16, addr32, addr64, or addrF16().

Parameters

x	column index, zero or greater, and less than width()
y	row index, zero or greater, and less than height()

Returns: readable generic pointer to pixel

◆ addr16() [1/2]

const uint16_t* SkPixmap::addr16 ( ) const

inline

Returns readable base pixel address.

Result is addressable as unsigned 16-bit words. Will trigger an assert() if SkColorType is not kRGB_565_SkColorType or kARGB_4444_SkColorType, and is built with SK_DEBUG defined.

One word corresponds to one pixel.

Returns: readable unsigned 16-bit pointer to pixels

◆ addr16() [2/2]

const uint16_t* SkPixmap::addr16	(	int	x,
		int	y
	)		const

inline

Returns readable pixel address at (x, y).

Input is not validated: out of bounds values of x or y trigger an assert() if built with SK_DEBUG defined.

Will trigger an assert() if SkColorType is not kRGB_565_SkColorType or kARGB_4444_SkColorType, and is built with SK_DEBUG defined.

Parameters

x	column index, zero or greater, and less than width()
y	row index, zero or greater, and less than height()

Returns: readable unsigned 16-bit pointer to pixel at (x, y)

◆ addr32() [1/2]

const uint32_t* SkPixmap::addr32 ( ) const

inline

Returns readable base pixel address.

Result is addressable as unsigned 32-bit words. Will trigger an assert() if SkColorType is not kRGBA_8888_SkColorType or kBGRA_8888_SkColorType, and is built with SK_DEBUG defined.

One word corresponds to one pixel.

Returns: readable unsigned 32-bit pointer to pixels

◆ addr32() [2/2]

const uint32_t* SkPixmap::addr32	(	int	x,
		int	y
	)		const

inline

Returns readable pixel address at (x, y).

Input is not validated: out of bounds values of x or y trigger an assert() if built with SK_DEBUG defined.

Will trigger an assert() if SkColorType is not kRGBA_8888_SkColorType or kBGRA_8888_SkColorType, and is built with SK_DEBUG defined.

Parameters

x	column index, zero or greater, and less than width()
y	row index, zero or greater, and less than height()

Returns: readable unsigned 32-bit pointer to pixel at (x, y)

◆ addr64() [1/2]

const uint64_t* SkPixmap::addr64 ( ) const

inline

Returns readable base pixel address.

Result is addressable as unsigned 64-bit words. Will trigger an assert() if SkColorType is not kRGBA_F16_SkColorType and is built with SK_DEBUG defined.

One word corresponds to one pixel.

Returns: readable unsigned 64-bit pointer to pixels

◆ addr64() [2/2]

const uint64_t* SkPixmap::addr64	(	int	x,
		int	y
	)		const

inline

Returns readable pixel address at (x, y).

Input is not validated: out of bounds values of x or y trigger an assert() if built with SK_DEBUG defined.

Will trigger an assert() if SkColorType is not kRGBA_F16_SkColorType and is built with SK_DEBUG defined.

Parameters

x	column index, zero or greater, and less than width()
y	row index, zero or greater, and less than height()

Returns: readable unsigned 64-bit pointer to pixel at (x, y)

◆ addr8() [1/2]

const uint8_t* SkPixmap::addr8 ( ) const

inline

Returns readable base pixel address.

Result is addressable as unsigned 8-bit bytes. Will trigger an assert() if SkColorType is not kAlpha_8_SkColorType or kGray_8_SkColorType, and is built with SK_DEBUG defined.

One byte corresponds to one pixel.

Returns: readable unsigned 8-bit pointer to pixels

◆ addr8() [2/2]

const uint8_t* SkPixmap::addr8	(	int	x,
		int	y
	)		const

inline

Returns readable pixel address at (x, y).

Input is not validated: out of bounds values of x or y trigger an assert() if built with SK_DEBUG defined.

Will trigger an assert() if SkColorType is not kAlpha_8_SkColorType or kGray_8_SkColorType, and is built with SK_DEBUG defined.

Parameters

x	column index, zero or greater, and less than width()
y	row index, zero or greater, and less than height()

Returns: readable unsigned 8-bit pointer to pixel at (x, y)

◆ addrF16() [1/2]

const uint16_t* SkPixmap::addrF16 ( ) const

inline

Returns readable base pixel address.

Result is addressable as unsigned 16-bit words. Will trigger an assert() if SkColorType is not kRGBA_F16_SkColorType and is built with SK_DEBUG defined.

Each word represents one color component encoded as a half float. Four words correspond to one pixel.

Returns: readable unsigned 16-bit pointer to first component of pixels

◆ addrF16() [2/2]

const uint16_t* SkPixmap::addrF16	(	int	x,
		int	y
	)		const

inline

Returns readable pixel address at (x, y).

Input is not validated: out of bounds values of x or y trigger an assert() if built with SK_DEBUG defined.

Will trigger an assert() if SkColorType is not kRGBA_F16_SkColorType and is built with SK_DEBUG defined.

Each unsigned 16-bit word represents one color component encoded as a half float. Four words correspond to one pixel.

Parameters

x	column index, zero or greater, and less than width()
y	row index, zero or greater, and less than height()

Returns: readable unsigned 16-bit pointer to pixel component at (x, y)

◆ alphaType()

SkAlphaType SkPixmap::alphaType ( ) const

inline

◆ bounds()

SkIRect SkPixmap::bounds ( ) const

inline

Returns SkIRect { 0, 0, width(), height() }.

Returns: integral rectangle from origin to width() and height()

◆ colorSpace()

SkColorSpace* SkPixmap::colorSpace ( ) const

Returns SkColorSpace, the range of colors, associated with SkImageInfo.

The reference count of SkColorSpace is unchanged. The returned SkColorSpace is immutable.

Returns: SkColorSpace in SkImageInfo, or nullptr

◆ colorType()

SkColorType SkPixmap::colorType ( ) const

inline

◆ computeByteSize()

size_t SkPixmap::computeByteSize ( ) const

inline

Returns minimum memory required for pixel storage.

Does not include unused memory on last row when rowBytesAsPixels() exceeds width(). Returns SIZE_MAX if result does not fit in size_t. Returns zero if height() or width() is 0. Returns height() times rowBytes() if colorType() is kUnknown_SkColorType.

Returns: size in bytes of image buffer

◆ computeIsOpaque()

bool SkPixmap::computeIsOpaque ( ) const

Returns true if all pixels are opaque.

SkColorType determines how pixels are encoded, and whether pixel describes alpha. Returns true for SkColorType without alpha in each pixel; for other SkColorType, returns true if all pixels have alpha values equivalent to 1.0 or greater.

For SkColorType kRGB_565_SkColorType or kGray_8_SkColorType: always returns true. For SkColorType kAlpha_8_SkColorType, kBGRA_8888_SkColorType, kRGBA_8888_SkColorType: returns true if all pixel alpha values are 255. For SkColorType kARGB_4444_SkColorType: returns true if all pixel alpha values are 15. For kRGBA_F16_SkColorType: returns true if all pixel alpha values are 1.0 or greater.

Returns false for kUnknown_SkColorType.

Returns: true if all pixels have opaque values or SkColorType is opaque

example: https://fiddle.skia.org/c/@Pixmap_computeIsOpaque

◆ dimensions()

SkISize SkPixmap::dimensions ( ) const

inline

Return the dimensions of the pixmap (from its ImageInfo)

◆ erase() [1/3]

bool SkPixmap::erase	(	const SkColor4f &	color,
		const SkIRect *	subset = `nullptr`
	)		const

Writes color to pixels bounded by subset; returns true on success.

if subset is nullptr, writes colors pixels inside bounds(). Returns false if colorType() is kUnknown_SkColorType, if subset is not nullptr and does not intersect bounds(), or if subset is nullptr and bounds() is empty.

Parameters

color	unpremultiplied color to write
subset	bounding integer SkRect of pixels to write; may be nullptr

Returns: true if pixels are changed

◆ erase() [2/3]

bool SkPixmap::erase ( SkColor color ) const

inline

Writes color to pixels inside bounds(); returns true on success.

Returns false if colorType() is kUnknown_SkColorType, or if bounds() is empty.

Parameters

color sRGB unpremultiplied color to write

Returns: true if pixels are changed

◆ erase() [3/3]

bool SkPixmap::erase	(	SkColor	color,
		const SkIRect &	subset
	)		const

Writes color to pixels bounded by subset; returns true on success.

Returns false if colorType() is kUnknown_SkColorType, or if subset does not intersect bounds().

Parameters

color	sRGB unpremultiplied color to write
subset	bounding integer SkRect of written pixels

Returns: true if pixels are changed

example: https://fiddle.skia.org/c/@Pixmap_erase

◆ extractSubset()

bool SkPixmap::extractSubset	(	SkPixmap *	subset,
		const SkIRect &	area
	)		const

Sets subset width, height, pixel address to intersection of SkPixmap with area, if intersection is not empty; and return true.

Otherwise, leave subset unchanged and return false.

Failing to read the return value generates a compile time warning.

Parameters

subset	storage for width, height, pixel address of intersection
area	bounds to intersect with SkPixmap

Returns: true if intersection of SkPixmap and area is not empty

◆ getAlphaf()

float SkPixmap::getAlphaf	(	int	x,
		int	y
	)		const

Look up the pixel at (x,y) and return its alpha component, normalized to [0..1].

This is roughly equivalent to SkGetColorA(getColor()), but can be more efficent (and more precise if the pixels store more than 8 bits per component).

Parameters

x	column index, zero or greater, and less than width()
y	row index, zero or greater, and less than height()

Returns: alpha converted to normalized float

◆ getColor()

SkColor SkPixmap::getColor	(	int	x,
		int	y
	)		const

Returns pixel at (x, y) as unpremultiplied color.

Returns black with alpha if SkColorType is kAlpha_8_SkColorType.

Input is not validated: out of bounds values of x or y trigger an assert() if built with SK_DEBUG defined; and returns undefined values or may crash if SK_RELEASE is defined. Fails if SkColorType is kUnknown_SkColorType or pixel address is nullptr.

SkColorSpace in SkImageInfo is ignored. Some color precision may be lost in the conversion to unpremultiplied color; original pixel data may have additional precision.

Parameters

x	column index, zero or greater, and less than width()
y	row index, zero or greater, and less than height()

Returns: pixel converted to unpremultiplied color

example: https://fiddle.skia.org/c/@Pixmap_getColor

◆ getColor4f()

SkColor4f SkPixmap::getColor4f	(	int	x,
		int	y
	)		const

Returns pixel at (x, y) as unpremultiplied color as an SkColor4f.

Returns black with alpha if SkColorType is kAlpha_8_SkColorType.

Input is not validated: out of bounds values of x or y trigger an assert() if built with SK_DEBUG defined; and returns undefined values or may crash if SK_RELEASE is defined. Fails if SkColorType is kUnknown_SkColorType or pixel address is nullptr.

SkColorSpace in SkImageInfo is ignored. Some color precision may be lost in the conversion to unpremultiplied color; original pixel data may have additional precision, though this is less likely than for getColor(). Rounding errors may occur if the underlying type has lower precision.

Parameters

x	column index, zero or greater, and less than width()
y	row index, zero or greater, and less than height()

Returns: pixel converted to unpremultiplied float color

◆ height()

int SkPixmap::height ( ) const

inline

Returns pixel row count.

Returns: pixel height in SkImageInfo

◆ info()

const SkImageInfo& SkPixmap::info ( ) const

inline

Returns width, height, SkAlphaType, SkColorType, and SkColorSpace.

Returns: reference to SkImageInfo

◆ isOpaque()

bool SkPixmap::isOpaque ( ) const

inline

Returns true if SkAlphaType is kOpaque_SkAlphaType.

Does not check if SkColorType allows alpha, or if any pixel value has transparency.

Returns: true if SkImageInfo has opaque SkAlphaType

◆ readPixels() [1/4]

bool SkPixmap::readPixels	(	const SkImageInfo &	dstInfo,
		void *	dstPixels,
		size_t	dstRowBytes
	)		const

inline

Copies a SkRect of pixels to dstPixels.

Copy starts at (0, 0), and does not exceed SkPixmap (width(), height()).

dstInfo specifies width, height, SkColorType, SkAlphaType, and SkColorSpace of destination. dstRowBytes specifics the gap from one destination row to the next. Returns true if pixels are copied. Returns false if dstInfo address equals nullptr, or dstRowBytes is less than dstInfo.minRowBytes().

Pixels are copied only if pixel conversion is possible. If SkPixmap colorType() is kGray_8_SkColorType, or kAlpha_8_SkColorType; dstInfo.colorType() must match. If SkPixmap colorType() is kGray_8_SkColorType, dstInfo.colorSpace() must match. If SkPixmap alphaType() is kOpaque_SkAlphaType, dstInfo.alphaType() must match. If SkPixmap colorSpace() is nullptr, dstInfo.colorSpace() must match. Returns false if pixel conversion is not possible.

Returns false if SkPixmap width() or height() is zero or negative.

Parameters

dstInfo	destination width, height, SkColorType, SkAlphaType, SkColorSpace
dstPixels	destination pixel storage
dstRowBytes	destination row length

Returns: true if pixels are copied to dstPixels

◆ readPixels() [2/4]

bool SkPixmap::readPixels	(	const SkImageInfo &	dstInfo,
		void *	dstPixels,
		size_t	dstRowBytes,
		int	srcX,
		int	srcY
	)		const

Copies a SkRect of pixels to dstPixels.

Copy starts at (srcX, srcY), and does not exceed SkPixmap (width(), height()).

dstInfo specifies width, height, SkColorType, SkAlphaType, and SkColorSpace of destination. dstRowBytes specifics the gap from one destination row to the next. Returns true if pixels are copied. Returns false if dstInfo address equals nullptr, or dstRowBytes is less than dstInfo.minRowBytes().

Pixels are copied only if pixel conversion is possible. If SkPixmap colorType() is kGray_8_SkColorType, or kAlpha_8_SkColorType; dstInfo.colorType() must match. If SkPixmap colorType() is kGray_8_SkColorType, dstInfo.colorSpace() must match. If SkPixmap alphaType() is kOpaque_SkAlphaType, dstInfo.alphaType() must match. If SkPixmap colorSpace() is nullptr, dstInfo.colorSpace() must match. Returns false if pixel conversion is not possible.

srcX and srcY may be negative to copy only top or left of source. Returns false if SkPixmap width() or height() is zero or negative. Returns false if: abs(srcX) >= Pixmap width(), or if abs(srcY) >= Pixmap height().

Parameters

dstInfo	destination width, height, SkColorType, SkAlphaType, SkColorSpace
dstPixels	destination pixel storage
dstRowBytes	destination row length
srcX	column index whose absolute value is less than width()
srcY	row index whose absolute value is less than height()

Returns: true if pixels are copied to dstPixels

◆ readPixels() [3/4]

bool SkPixmap::readPixels ( const SkPixmap & dst ) const

inline

Copies pixels inside bounds() to dst.

dst specifies width, height, SkColorType, SkAlphaType, and SkColorSpace of destination. Returns true if pixels are copied. Returns false if dst address equals nullptr, or dst.rowBytes() is less than dst SkImageInfo::minRowBytes.

Pixels are copied only if pixel conversion is possible. If SkPixmap colorType() is kGray_8_SkColorType, or kAlpha_8_SkColorType; dst SkColorType must match. If SkPixmap colorType() is kGray_8_SkColorType, dst SkColorSpace must match. If SkPixmap alphaType() is kOpaque_SkAlphaType, dst SkAlphaType must match. If SkPixmap colorSpace() is nullptr, dst SkColorSpace must match. Returns false if pixel conversion is not possible.

Returns false if SkPixmap width() or height() is zero or negative.

Parameters

dst	SkImageInfo and pixel address to write to

Returns: true if pixels are copied to dst

◆ readPixels() [4/4]

bool SkPixmap::readPixels	(	const SkPixmap &	dst,
		int	srcX,
		int	srcY
	)		const

inline

Copies a SkRect of pixels to dst.

Copy starts at (srcX, srcY), and does not exceed SkPixmap (width(), height()). dst specifies width, height, SkColorType, SkAlphaType, and SkColorSpace of destination. Returns true if pixels are copied. Returns false if dst address equals nullptr, or dst.rowBytes() is less than dst SkImageInfo::minRowBytes.

Pixels are copied only if pixel conversion is possible. If SkPixmap colorType() is kGray_8_SkColorType, or kAlpha_8_SkColorType; dst.info().colorType must match. If SkPixmap colorType() is kGray_8_SkColorType, dst.info().colorSpace must match. If SkPixmap alphaType() is kOpaque_SkAlphaType, dst.info().alphaType must match. If SkPixmap colorSpace() is nullptr, dst.info().colorSpace must match. Returns false if pixel conversion is not possible.

srcX and srcY may be negative to copy only top or left of source. Returns false SkPixmap width() or height() is zero or negative. Returns false if: abs(srcX) >= Pixmap width(), or if abs(srcY) >= Pixmap height().

Parameters

dst	SkImageInfo and pixel address to write to
srcX	column index whose absolute value is less than width()
srcY	row index whose absolute value is less than height()

Returns: true if pixels are copied to dst

◆ refColorSpace()

sk_sp<SkColorSpace> SkPixmap::refColorSpace ( ) const

Returns smart pointer to SkColorSpace, the range of colors, associated with SkImageInfo.

The smart pointer tracks the number of objects sharing this SkColorSpace reference so the memory is released when the owners destruct.

The returned SkColorSpace is immutable.

Returns: SkColorSpace in SkImageInfo wrapped in a smart pointer

◆ reset() [1/3]

void SkPixmap::reset ( )

Sets width, height, row bytes to zero; pixel address to nullptr; SkColorType to kUnknown_SkColorType; and SkAlphaType to kUnknown_SkAlphaType.

The prior pixels are unaffected; it is up to the caller to release pixels memory if desired.

example: https://fiddle.skia.org/c/@Pixmap_reset

◆ reset() [2/3]

void SkPixmap::reset	(	const SkImageInfo &	info,
		const void *	addr,
		size_t	rowBytes
	)

Sets width, height, SkAlphaType, and SkColorType from info.

Sets pixel address from addr, which may be nullptr. Sets row bytes from rowBytes, which should be info.width() times info.bytesPerPixel(), or larger.

Does not check addr. Asserts if built with SK_DEBUG defined and if rowBytes is too small to hold one row of pixels.

The memory lifetime pixels are managed by the caller. When SkPixmap goes out of scope, addr is unaffected.

Parameters

info	width, height, SkAlphaType, SkColorType of SkImageInfo
addr	pointer to pixels allocated by caller; may be nullptr
rowBytes	size of one row of addr; width times pixel size, or larger

example: https://fiddle.skia.org/c/@Pixmap_reset_2

◆ reset() [3/3]

bool SkPixmap::reset ( const SkMask & mask )

Deprecated.

◆ rowBytes()

size_t SkPixmap::rowBytes ( ) const

inline

Returns row bytes, the interval from one pixel row to the next.

Row bytes is at least as large as: width() * info().bytesPerPixel().

Returns zero if colorType() is kUnknown_SkColorType. It is up to the SkBitmap creator to ensure that row bytes is a useful value.

Returns: byte length of pixel row

◆ rowBytesAsPixels()

int SkPixmap::rowBytesAsPixels ( ) const

inline

Returns number of pixels that fit on row.

Should be greater than or equal to width().

Returns: maximum pixels per row

◆ scalePixels()

bool SkPixmap::scalePixels	(	const SkPixmap &	dst,
		const SkSamplingOptions &
	)		const

Copies SkBitmap to dst, scaling pixels to fit dst.width() and dst.height(), and converting pixels to match dst.colorType() and dst.alphaType().

Returns true if pixels are copied. Returns false if dst address is nullptr, or dst.rowBytes() is less than dst SkImageInfo::minRowBytes.

Pixels are copied only if pixel conversion is possible. If SkPixmap colorType() is kGray_8_SkColorType, or kAlpha_8_SkColorType; dst SkColorType must match. If SkPixmap colorType() is kGray_8_SkColorType, dst SkColorSpace must match. If SkPixmap alphaType() is kOpaque_SkAlphaType, dst SkAlphaType must match. If SkPixmap colorSpace() is nullptr, dst SkColorSpace must match. Returns false if pixel conversion is not possible.

Returns false if SkBitmap width() or height() is zero or negative.

Parameters

dst	SkImageInfo and pixel address to write to

Returns: true if pixels are scaled to fit dst

example: https://fiddle.skia.org/c/@Pixmap_scalePixels

◆ setColorSpace()

void SkPixmap::setColorSpace ( sk_sp< SkColorSpace > colorSpace )

Changes SkColorSpace in SkImageInfo; preserves width, height, SkAlphaType, and SkColorType in SkImage, and leaves pixel address and row bytes unchanged.

SkColorSpace reference count is incremented.

Parameters

colorSpace SkColorSpace moved to SkImageInfo

example: https://fiddle.skia.org/c/@Pixmap_setColorSpace

◆ shiftPerPixel()

int SkPixmap::shiftPerPixel ( ) const

inline

Returns bit shift converting row bytes to row pixels.

Returns zero for kUnknown_SkColorType.

Returns: one of: 0, 1, 2, 3; left shift to convert pixels to bytes

◆ width()

int SkPixmap::width ( ) const

inline

Returns pixel count in each pixel row.

Should be equal or less than: rowBytes() / info().bytesPerPixel().

Returns: pixel width in SkImageInfo

◆ writable_addr() [1/2]

void* SkPixmap::writable_addr ( ) const

inline

Returns writable base pixel address.

Returns: writable generic base pointer to pixels

◆ writable_addr() [2/2]

void* SkPixmap::writable_addr	(	int	x,
		int	y
	)		const

inline

Returns writable pixel address at (x, y).

Input is not validated: out of bounds values of x or y trigger an assert() if built with SK_DEBUG defined. Returns zero if SkColorType is kUnknown_SkColorType.

Parameters

x	column index, zero or greater, and less than width()
y	row index, zero or greater, and less than height()

Returns: writable generic pointer to pixel

◆ writable_addr16()

uint16_t* SkPixmap::writable_addr16	(	int	x,
		int	y
	)		const

inline

Returns writable_addr pixel address at (x, y).

Result is addressable as unsigned 16-bit words. Will trigger an assert() if SkColorType is not kRGB_565_SkColorType or kARGB_4444_SkColorType, and is built with SK_DEBUG defined.

One word corresponds to one pixel.

Parameters

x	column index, zero or greater, and less than width()
y	row index, zero or greater, and less than height()

Returns: writable unsigned 16-bit pointer to pixel

◆ writable_addr32()

uint32_t* SkPixmap::writable_addr32	(	int	x,
		int	y
	)		const

inline

Returns writable pixel address at (x, y).

Result is addressable as unsigned 32-bit words. Will trigger an assert() if SkColorType is not kRGBA_8888_SkColorType or kBGRA_8888_SkColorType, and is built with SK_DEBUG defined.

One word corresponds to one pixel.

Parameters

x	column index, zero or greater, and less than width()
y	row index, zero or greater, and less than height()

Returns: writable unsigned 32-bit pointer to pixel

◆ writable_addr64()

uint64_t* SkPixmap::writable_addr64	(	int	x,
		int	y
	)		const

inline

Returns writable pixel address at (x, y).

Result is addressable as unsigned 64-bit words. Will trigger an assert() if SkColorType is not kRGBA_F16_SkColorType and is built with SK_DEBUG defined.

One word corresponds to one pixel.

Parameters

x	column index, zero or greater, and less than width()
y	row index, zero or greater, and less than height()

Returns: writable unsigned 64-bit pointer to pixel

◆ writable_addr8()

uint8_t* SkPixmap::writable_addr8	(	int	x,
		int	y
	)		const

inline

Returns writable pixel address at (x, y).

Result is addressable as unsigned 8-bit bytes. Will trigger an assert() if SkColorType is not kAlpha_8_SkColorType or kGray_8_SkColorType, and is built with SK_DEBUG defined.

One byte corresponds to one pixel.

Parameters

x	column index, zero or greater, and less than width()
y	row index, zero or greater, and less than height()

Returns: writable unsigned 8-bit pointer to pixels

◆ writable_addrF16()

uint16_t* SkPixmap::writable_addrF16	(	int	x,
		int	y
	)		const

inline

Returns writable pixel address at (x, y).

Result is addressable as unsigned 16-bit words. Will trigger an assert() if SkColorType is not kRGBA_F16_SkColorType and is built with SK_DEBUG defined.

Each word represents one color component encoded as a half float. Four words correspond to one pixel.

Parameters

x	column index, zero or greater, and less than width()
y	row index, zero or greater, and less than height()

Returns: writable unsigned 16-bit pointer to first component of pixel

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

/CHECKOUT/include/core/SkPixmap.h

Public Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ SkPixmap() [1/2]

◆ SkPixmap() [2/2]

Member Function Documentation

◆ addr() [1/2]

◆ addr() [2/2]

◆ addr16() [1/2]

◆ addr16() [2/2]

◆ addr32() [1/2]

◆ addr32() [2/2]

◆ addr64() [1/2]

◆ addr64() [2/2]

◆ addr8() [1/2]

◆ addr8() [2/2]

◆ addrF16() [1/2]

◆ addrF16() [2/2]

◆ alphaType()

◆ bounds()

◆ colorSpace()

◆ colorType()

◆ computeByteSize()

◆ computeIsOpaque()

◆ dimensions()

◆ erase() [1/3]

◆ erase() [2/3]

◆ erase() [3/3]

◆ extractSubset()

◆ getAlphaf()

◆ getColor()

◆ getColor4f()

◆ height()

◆ info()

◆ isOpaque()

◆ readPixels() [1/4]

◆ readPixels() [2/4]

◆ readPixels() [3/4]

◆ readPixels() [4/4]

◆ refColorSpace()

◆ reset() [1/3]

◆ reset() [2/3]

◆ reset() [3/3]

◆ rowBytes()

◆ rowBytesAsPixels()

◆ scalePixels()

◆ setColorSpace()

◆ shiftPerPixel()

◆ width()

◆ writable_addr() [1/2]

◆ writable_addr() [2/2]

◆ writable_addr16()

◆ writable_addr32()

◆ writable_addr64()

◆ writable_addr8()

◆ writable_addrF16()