Pixmap provides a utility to pair SkImageInfo with pixels and row bytes. Pixmap is a low level class which provides convenience functions to access raster destinations. Canvas can not draw Pixmap, nor does Pixmap provide a direct drawing destination.
Use Bitmap to draw pixels referenced by Pixmap; use Surface to draw into pixels referenced by Pixmap.
Pixmap does not try to manage the lifetime of the pixel memory. Use Pixel Ref to manage pixel memory; Pixel Ref is safe across threads.
SkPixmap global, struct, and class related member functions share a topic.
SkPixmap can be constructed or initialized by these functions, including C++ class constructors.
SkPixmap member functions read and modify the structure properties.
Creates an empty Pixmap 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 Pixmap has been created.
empty Pixmap
width: 0 height: 0 color: kUnknown_SkColorType alpha: kUnknown_SkAlphaType width: 25 height: 35 color: kRGBA_8888_SkColorType alpha: kOpaque_SkAlphaType
SkPixmap(const SkImageInfo& info, const void* addr, size t rowBytes) reset[2][3] SkAlphaType SkColorType
Creates Pixmap 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 Pixmap goes out of scope, addr is unaffected.
Pixmap may be later modified by reset to change its size, pixel type, or storage.
initialized Pixmap
image alpha only = false copy alpha only = true
SkPixmap() reset[2][3] SkAlphaType SkColorType
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.
width: 25 height: 35 color: kRGBA_8888_SkColorType alpha: kOpaque_SkAlphaType width: 0 height: 0 color: kUnknown_SkColorType alpha: kUnknown_SkAlphaType
SkPixmap() SkAlphaType SkColorType
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 Pixmap goes out of scope, addr is unaffected.
SkPixmap(const SkImageInfo& info, const void* addr, size t rowBytes) reset[2][3] SkAlphaType SkColorType
Changes Color Space in Image Info; preserves width, height, SkAlphaType, and SkColorType in Image, and leaves pixel address and row bytes unchanged. Color Space reference count is incremented.
is unique is not unique
Color Space SkImageInfo::makeColorSpace
To be deprecated soon.
Sets subset width, height, pixel address to intersection of Pixmap 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.
true if intersection of Pixmap and area is not empty
reset[2][3] SkIRect::intersect[2][3]
Returns width, height, Alpha Type, Color Type, and Color Space.
reference to ImageInfo
width: 384 height: 384 color: BGRA_8888 alpha: Opaque
Image Info
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 Bitmap creator to ensure that row bytes is a useful value.
byte length of pixel row
rowBytes: 2 minRowBytes: 4 rowBytes: 8 minRowBytes: 4
addr[2] info SkImageInfo::minRowBytes
Returns pixel address, the base address corresponding to the pixel origin.
It is up to the Pixmap creator to ensure that pixel address is a useful value.
pixel address
#Volatile pixels address: 0x7f2a440bb010 inset address: 0x7f2a440fb210
addr(int x, int y) addr8[2] addr16[2] addr32[2] addr64[2] info rowBytes
Returns pixel count in each pixel row. Should be equal or less than:
rowBytes / info.bytesPerPixel().
pixel width in Image Info
pixmap width: 16 info width: 16
height SkImageInfo::width()
Returns pixel row count.
pixel height in Image Info
pixmap height: 32 info height: 32
width ImageInfo::height()
Returns Color Type, one of: kUnknown_SkColorType, kAlpha_8_SkColorType, kRGB_565_SkColorType, kARGB_4444_SkColorType, kRGBA_8888_SkColorType, kRGB_888x_SkColorType, kBGRA_8888_SkColorType, kRGBA_1010102_SkColorType, kRGB_101010x_SkColorType, kGray_8_SkColorType, kRGBA_F16_SkColorType.
Color Type in Image Info
color type: kAlpha_8_SkColorType
alphaType SkImageInfo::colorType
Returns Alpha Type, one of: kUnknown_SkAlphaType, kOpaque_SkAlphaType, kPremul_SkAlphaType, kUnpremul_SkAlphaType.
Alpha Type in Image Info
alpha type: kPremul_SkAlphaType
colorType SkImageInfo::alphaType
Returns Color Space, the range of colors, associated with Image Info. The reference count of Color Space is unchanged. The returned Color Space is immutable.
Color Space in Image Info, or nullptr
gammaCloseToSRGB: false gammaIsLinear: true isSRGB: false
Color Space SkImageInfo::colorSpace
Returns true if Alpha Type is kOpaque_SkAlphaType. Does not check if Color Type allows Alpha, or if any pixel value has transparency.
true if Image Info has opaque Alpha Type
isOpaque: false isOpaque: false isOpaque: true isOpaque: true
computeIsOpaque SkImageInfo::isOpaque
Returns IRect { 0, 0, width, height }.
integral rectangle from origin to width and height
width: 0 height: 0 empty: true width: 0 height: 2 empty: true width: 2 height: 0 empty: true width: 2 height: 2 empty: false
height width IRect
Returns number of pixels that fit on row. Should be greater than or equal to width.
maximum pixels per row
rowBytes: 4 rowBytesAsPixels: 1 rowBytes: 5 rowBytesAsPixels: 1 rowBytes: 6 rowBytesAsPixels: 1 rowBytes: 7 rowBytesAsPixels: 1 rowBytes: 8 rowBytesAsPixels: 2
rowBytes shiftPerPixel width SkImageInfo::bytesPerPixel
Returns bit shift converting row bytes to row pixels. Returns zero for kUnknown_SkColorType.
one of: 0, 1, 2, 3; left shift to convert pixels to bytes
color: kUnknown_SkColorType bytesPerPixel: 0 shiftPerPixel: 0 color: kAlpha_8_SkColorType bytesPerPixel: 1 shiftPerPixel: 0 color: kRGB_565_SkColorType bytesPerPixel: 2 shiftPerPixel: 1 color: kARGB_4444_SkColorType bytesPerPixel: 2 shiftPerPixel: 1 color: kRGBA_8888_SkColorType bytesPerPixel: 4 shiftPerPixel: 2 color: kBGRA_8888_SkColorType bytesPerPixel: 4 shiftPerPixel: 2 color: kGray_8_SkColorType bytesPerPixel: 1 shiftPerPixel: 0 color: kRGBA_F16_SkColorType bytesPerPixel: 8 shiftPerPixel: 3
rowBytes rowBytesAsPixels width SkImageInfo::bytesPerPixel
Returns minimum memory required for pixel storage. Does not include unused memory on last row when rowBytesAsPixels exceeds width. Returns zero 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.
size in bytes of image buffer
width: 1 height: 1 computeByteSize: 4 width: 1 height: 1000 computeByteSize: 4999 width: 1 height: 1000000 computeByteSize: 4999999 width: 1000 height: 1 computeByteSize: 4000 width: 1000 height: 1000 computeByteSize: 4999000 width: 1000 height: 1000000 computeByteSize: 4999999000 width: 1000000 height: 1 computeByteSize: 4000000 width: 1000000 height: 1000 computeByteSize: 4999000000 width: 1000000 height: 1000000 computeByteSize: 4999999000000
SkImageInfo::computeByteSize
Returns true if all pixels are opaque. Color Type determines how pixels are encoded, and whether pixel describes Alpha. Returns true for Color Types without alpha in each pixel; for other Color Types, returns true if all pixels have alpha values equivalent to 1.0 or greater.
For Color Types kRGB_565_SkColorType or kGray_8_SkColorType: always returns true. For Color Types kAlpha_8_SkColorType, kBGRA_8888_SkColorType, kRGBA_8888_SkColorType: returns true if all pixel Alpha values are 255. For Color Type 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.
true if all pixels have opaque values or Color Type is opaque
computeIsOpaque: false computeIsOpaque: true computeIsOpaque: false computeIsOpaque: true
isOpaque Color Type Alpha
Returns pixel at (x, y) as Unpremultiplied Color. Returns black with Alpha if Color Type 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 Color Type is kUnknown_SkColorType or pixel address is nullptr.
Color Space in Image Info is ignored. Some Color precision may be lost in the conversion to Unpremultiplied Color; original pixel data may have additional precision.
pixel converted to Unpremultiplied Color
Premultiplied: (0, 0) 0x00000000 0x2a0e002a 0x55380055 0x7f7f007f (0, 1) 0x2a000e2a 0x551c1c55 0x7f542a7f 0xaaaa38aa (0, 2) 0x55003855 0x7f2a547f 0xaa7171aa 0xd4d48dd4 (0, 3) 0x7f007f7f 0xaa38aaaa 0xd48dd4d4 0xffffffff Unpremultiplied: (0, 0) 0x00000000 0x2a5500ff 0x55a800ff 0x7fff00ff (0, 1) 0x2a0055ff 0x555454ff 0x7fa954ff 0xaaff54ff (0, 2) 0x5500a8ff 0x7f54a9ff 0xaaaaaaff 0xd4ffaaff (0, 3) 0x7f00ffff 0xaa54ffff 0xd4aaffff 0xffffffff
getAlphaf addr[2] readPixels[2][3][4]
Looks 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).
alpha converted to normalized float
getColor
Returns readable pixel address at (x, y). Returns nullptr if Pixel Ref 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 Color Type is kUnknown_SkColorType.
Performs a lookup of pixel size; for better performance, call one of: addr8, addr16, addr32, addr64, or addrF16.
readable generic pointer to pixel
pixmap.addr(1, 2) == &storage[1 + 2 * w]
addr8[2] addr16[2] addr32[2] addr64[2] addrF16[2] getColor writable addr[2] SkBitmap::getAddr
Returns readable base pixel address. Result is addressable as unsigned 8-bit bytes. Will trigger an assert() if Color Type is not kAlpha_8_SkColorType or kGray_8_SkColorType, and is built with SK_DEBUG defined.
One byte corresponds to one pixel.
readable unsigned 8-bit pointer to pixels
pixmap.addr8() == storage
addr[2] addr16[2] addr32[2] addr64[2] addrF16[2] getColor writable addr[2] writable addr8
Returns readable base pixel address. Result is addressable as unsigned 16-bit words. Will trigger an assert() if Color Type is not kRGB_565_SkColorType or kARGB_4444_SkColorType, and is built with SK_DEBUG defined.
One word corresponds to one pixel.
readable unsigned 16-bit pointer to pixels
pixmap.addr16() == storage
addr[2] addr8[2] addr32[2] addr64[2] addrF16[2] getColor writable addr[2] writable addr16
Returns readable base pixel address. Result is addressable as unsigned 32-bit words. Will trigger an assert() if Color Type is not kRGBA_8888_SkColorType or kBGRA_8888_SkColorType, and is built with SK_DEBUG defined.
One word corresponds to one pixel.
readable unsigned 32-bit pointer to pixels
pixmap.addr32() == storage
addr[2] addr8[2] addr16[2] addr64[2] addrF16[2] getColor writable addr[2] writable addr32
Returns readable base pixel address. Result is addressable as unsigned 64-bit words. Will trigger an assert() if Color Type is not kRGBA_F16_SkColorType and is built with SK_DEBUG defined.
One word corresponds to one pixel.
readable unsigned 64-bit pointer to pixels
pixmap.addr64() == storage
addr[2] addr8[2] addr16[2] addr32[2] addrF16[2] getColor writable addr[2] writable addr64
Returns readable base pixel address. Result is addressable as unsigned 16-bit words. Will trigger an assert() if Color Type 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.
readable unsigned 16-bit pointer to first component of pixels
pixmap.addrF16() == storage
addr[2] addr8[2] addr16[2] addr32[2] addr64[2] getColor writable addr[2] writable addrF16
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 Color Type is not kAlpha_8_SkColorType or kGray_8_SkColorType, and is built with SK_DEBUG defined.
readable unsigned 8-bit pointer to pixel at (x, y)
pixmap.addr8(1, 2) == &storage[1 + 2 * w]
addr[2] addr16[2] addr32[2] addr64[2] addrF16[2] getColor writable addr[2] writable addr8
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 Color Type is not kRGB_565_SkColorType or kARGB_4444_SkColorType, and is built with SK_DEBUG defined.
readable unsigned 16-bit pointer to pixel at (x, y)
pixmap.addr16(1, 2) == &storage[1 + 2 * w]
addr[2] addr8[2] addr32[2] addr64[2] addrF16[2] getColor writable addr[2] writable addr16
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 Color Type is not kRGBA_8888_SkColorType or kBGRA_8888_SkColorType, and is built with SK_DEBUG defined.
readable unsigned 32-bit pointer to pixel at (x, y)
pixmap.addr32(1, 2) == &storage[1 + 2 * w]
addr[2] addr8[2] addr16[2] addr64[2] addrF16[2] getColor writable addr[2] writable addr64
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 Color Type is not kRGBA_F16_SkColorType and is built with SK_DEBUG defined.
readable unsigned 64-bit pointer to pixel at (x, y)
pixmap.addr64(1, 2) == &storage[1 + 2 * w]
addr[2] addr8[2] addr16[2] addr32[2] addrF16[2] getColor writable addr[2] writable addr64
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 Color Type 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.
readable unsigned 16-bit pointer to pixel component at (x, y)
pixmap.addrF16(1, 2) == &storage[1 * wordsPerPixel + 2 * rowWords]
addr[2] addr8[2] addr16[2] addr32[2] addr64[2] getColor writable addr[2] writable addrF16
Returns writable base pixel address.
writable generic base pointer to pixels
pixmap.writable_addr() == (void *)storage pixmap.getColor(0, 1) == 0x00000000 pixmap.getColor(0, 0) == 0xFFFFFFFF
writable addr8 writable addr16 writable addr32 writable addr64 writable addrF16 addr[2]
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 Color Type is kUnknown_SkColorType.
writable generic pointer to pixel
pixmap.writable_addr() == (void *)storage pixmap.getColor(0, 0) == 0x00000000 pixmap.getColor(1, 2) == 0xFFFFFFFF
writable addr8 writable addr16 writable addr32 writable addr64 writable addrF16 addr[2]
Returns writable pixel address at (x, y). Result is addressable as unsigned 8-bit bytes. Will trigger an assert() if Color Type is not kAlpha_8_SkColorType or kGray_8_SkColorType, and is built with SK_DEBUG defined.
One byte corresponds to one pixel.
writable unsigned 8-bit pointer to pixels
writable addr[2] writable addr16 writable addr32 writable addr64 writable addrF16 addr[2] addr8[2]
Returns writable addr pixel address at (x, y). Result is addressable as unsigned 16-bit words. Will trigger an assert() if Color Type is not kRGB_565_SkColorType or kARGB_4444_SkColorType, and is built with SK_DEBUG defined.
One word corresponds to one pixel.
writable unsigned 16-bit pointer to pixel
writable addr[2] writable addr8 writable addr32 writable addr64 writable addrF16 addr[2] addr16[2]
Returns writable pixel address at (x, y). Result is addressable as unsigned 32-bit words. Will trigger an assert() if Color Type is not kRGBA_8888_SkColorType or kBGRA_8888_SkColorType, and is built with SK_DEBUG defined.
One word corresponds to one pixel.
writable unsigned 32-bit pointer to pixel
writable addr[2] writable addr8 writable addr16 writable addr64 writable addrF16 addr[2] addr32[2]
Returns writable pixel address at (x, y). Result is addressable as unsigned 64-bit words. Will trigger an assert() if Color Type is not kRGBA_F16_SkColorType and is built with SK_DEBUG defined.
One word corresponds to one pixel.
writable unsigned 64-bit pointer to pixel
writable addr[2] writable addr8 writable addr16 writable addr32 writable addrF16 addr[2] addr64[2]
Returns writable pixel address at (x, y). Result is addressable as unsigned 16-bit words. Will trigger an assert() if Color Type 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.
writable unsigned 16-bit pointer to first component of pixel
writable addr[2] writable addr8 writable addr16 writable addr32 writable addr64 addr[2] addrF16[2]
Copies a Rect of pixels to dstPixels. Copy starts at (0, 0), and does not exceed Pixmap (width, height).
dstInfo specifies width, height, Color Type, Alpha Type, and Color Space of destination. dstRowBytes specifics the gap from one destination row to the next. Returns true if pixels are copied. Returns false if dstInfo.addr equals nullptr, or dstRowBytes is less than dstInfo.minRowBytes.
Pixels are copied only if pixel conversion is possible. If Pixmap colorType is kGray_8_SkColorType, or kAlpha_8_SkColorType; dstInfo.colorType must match. If Pixmap colorType is kGray_8_SkColorType, dstInfo.colorSpace must match. If Pixmap alphaType is kOpaque_SkAlphaType, dstInfo.alphaType must match. If Pixmap colorSpace is nullptr, dstInfo.colorSpace must match. Returns false if pixel conversion is not possible.
Returns false if Pixmap width or height is zero or negative.
true if pixels are copied to dstPixels
erase[2][3] SkBitmap::readPixels[2][3] SkCanvas::drawBitmap SkCanvas::readPixels[2][3] SkImage::readPixels[2] SkSurface::readPixels[2][3]
Copies a Rect of pixels to dstPixels. Copy starts at (srcX, srcY), and does not exceed Pixmap (width, height).
dstInfo specifies width, height, Color Type, Alpha Type, and Color Space of destination. dstRowBytes specifics the gap from one destination row to the next. Returns true if pixels are copied. Returns false if dstInfo.addr equals nullptr, or dstRowBytes is less than dstInfo.minRowBytes.
Pixels are copied only if pixel conversion is possible. If Pixmap colorType is kGray_8_SkColorType, or kAlpha_8_SkColorType; dstInfo.colorType must match. If Pixmap colorType is kGray_8_SkColorType, dstInfo.colorSpace must match. If Pixmap alphaType is kOpaque_SkAlphaType, dstInfo.alphaType must match. If Pixmap 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 Pixmap width or height is zero or negative. Returns false if:
abs(srcX) >= Pixmap width, or if abs(srcY) >= Pixmap height.
true if pixels are copied to dstPixels
erase[2][3] SkBitmap::readPixels[2][3] SkCanvas::drawBitmap SkCanvas::readPixels[2][3] SkImage::readPixels[2] SkSurface::readPixels[2][3]
Copies a Rect of pixels to dst. Copy starts at (srcX, srcY), and does not exceed Pixmap (width, height). dst specifies width, height, Color Type, Alpha Type, and Color Space of destination. Returns true if pixels are copied. Returns false if dst.addr equals nullptr, or dst.rowBytes is less than dst SkImageInfo::minRowBytes.
Pixels are copied only if pixel conversion is possible. If Pixmap colorType is kGray_8_SkColorType, or kAlpha_8_SkColorType; dst.info.colorType must match. If Pixmap colorType is kGray_8_SkColorType, dst.info.colorSpace must match. If Pixmap alphaType is kOpaque_SkAlphaType, dst.info.alphaType must match. If Pixmap 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 Pixmap width or height is zero or negative. Returns false if:
abs(srcX) >= Pixmap width, or if abs(srcY) >= Pixmap height.
true if pixels are copied to dst
erase[2][3] SkBitmap::readPixels[2][3] SkCanvas::drawBitmap SkCanvas::readPixels[2][3] SkImage::readPixels[2] SkSurface::readPixels[2][3]
Copies pixels inside bounds to dst. dst specifies width, height, Color Type, Alpha Type, and Color Space of destination. Returns true if pixels are copied. Returns false if dst.addr equals nullptr, or dst.rowBytes is less than dst SkImageInfo::minRowBytes.
Pixels are copied only if pixel conversion is possible. If Pixmap colorType is kGray_8_SkColorType, or kAlpha_8_SkColorType; dst Color Type must match. If Pixmap colorType is kGray_8_SkColorType, dst Color Space must match. If Pixmap alphaType is kOpaque_SkAlphaType, dst Alpha Type must match. If Pixmap colorSpace is nullptr, dst Color Space must match. Returns false if pixel conversion is not possible.
Returns false if Pixmap width or height is zero or negative.
true if pixels are copied to dst
erase[2][3] SkBitmap::readPixels[2][3] SkCanvas::drawBitmap SkCanvas::readPixels[2][3] SkImage::readPixels[2] SkSurface::readPixels[2][3]
Copies Bitmap 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.addr is nullptr, or dst.rowBytes is less than dst SkImageInfo::minRowBytes.
Pixels are copied only if pixel conversion is possible. If Pixmap colorType is kGray_8_SkColorType, or kAlpha_8_SkColorType; dst Color Type must match. If Pixmap colorType is kGray_8_SkColorType, dst Color Space must match. If Pixmap alphaType is kOpaque_SkAlphaType, dst Alpha Type must match. If Pixmap colorSpace is nullptr, dst Color Space must match. Returns false if pixel conversion is not possible.
Returns false if Bitmap width or height is zero or negative.
Scales the image, with filterQuality, to match dst.width and dst.height. filterQuality kNone_SkFilterQuality is fastest, typically implemented with Filter Quality Nearest Neighbor. kLow_SkFilterQuality is typically implemented with Filter Quality Bilerp. kMedium_SkFilterQuality is typically implemented with Filter Quality Bilerp, and Filter Quality MipMap when size is reduced. kHigh_SkFilterQuality is slowest, typically implemented with Filter Quality BiCubic.
true if pixels are scaled to fit dst
SkCanvas::drawBitmap SkImage::scalePixels
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.
true if pixels are changed
SkBitmap::erase SkCanvas::clear SkCanvas::drawColor
Writes color to pixels inside bounds; returns true on success. Returns false if colorType is kUnknown_SkColorType, or if bounds is empty.
true if pixels are changed
SkBitmap::erase SkCanvas::clear SkCanvas::drawColor
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.
true if pixels are changed
SkBitmap::erase SkCanvas::clear SkCanvas::drawColor