SkARGB32_Black_Blitter Class Reference

#include <SkCoreBlitters.h>

Inheritance diagram for SkARGB32_Black_Blitter:

Public Member Functions
	SkARGB32_Black_Blitter (const SkPixmap &device, const SkPaint &paint)
void	blitAntiH (int x, int y, const SkAlpha antialias[], const int16_t runs[]) override
void	blitAntiH2 (int x, int y, U8CPU a0, U8CPU a1) override
void	blitAntiV2 (int x, int y, U8CPU a0, U8CPU a1) override
Public Member Functions inherited from SkARGB32_Opaque_Blitter
	SkARGB32_Opaque_Blitter (const SkPixmap &device, const SkPaint &paint)
void	blitMask (const SkMask &, const SkIRect &) override
void	blitAntiH2 (int x, int y, U8CPU a0, U8CPU a1) override
void	blitAntiV2 (int x, int y, U8CPU a0, U8CPU a1) override
Public Member Functions inherited from SkARGB32_Blitter
	SkARGB32_Blitter (const SkPixmap &device, const SkPaint &paint)
void	blitH (int x, int y, int width) override
	Blit a horizontal run of one or more pixels.
void	blitAntiH (int x, int y, const SkAlpha antialias[], const int16_t runs[]) override
void	blitV (int x, int y, int height, SkAlpha alpha) override
	Blit a vertical run of pixels with a constant alpha value.
void	blitRect (int x, int y, int width, int height) override
	Blit a solid rectangle one or more pixels wide.
Public Member Functions inherited from SkRasterBlitter
	SkRasterBlitter (const SkPixmap &device)
Public Member Functions inherited from SkBlitter
virtual	~SkBlitter ()
virtual void	blitAntiRect (int x, int y, int width, int height, SkAlpha leftAlpha, SkAlpha rightAlpha)
void	blitFatAntiRect (const SkRect &rect)
virtual bool	isNullBlitter () const
virtual int	requestRowsPreserved () const
virtual void *	allocBlitMemory (size_t sz)
void	blitRectRegion (const SkIRect &rect, const SkRegion &clip)
void	blitRegion (const SkRegion &clip)

Additional Inherited Members
Static Public Member Functions inherited from SkBlitter
static bool	UseLegacyBlitter (const SkPixmap &, const SkPaint &, const SkMatrix &)
static SkBlitter *	Choose (const SkPixmap &dst, const SkMatrix &ctm, const SkPaint &paint, SkArenaAlloc *, bool drawCoverage, sk_sp< SkShader > clipShader, const SkSurfaceProps &props)
static SkBlitter *	ChooseSprite (const SkPixmap &dst, const SkPaint &, const SkPixmap &src, int left, int top, SkArenaAlloc *, sk_sp< SkShader > clipShader)
Protected Attributes inherited from SkARGB32_Blitter
SkColor	fColor
SkPMColor	fPMColor
Protected Attributes inherited from SkRasterBlitter
const SkPixmap	fDevice
Protected Attributes inherited from SkBlitter
SkAutoMalloc	fBlitMemory

Detailed Description

Definition at line 102 of file SkCoreBlitters.h.

Constructor & Destructor Documentation

SkARGB32_Black_Blitter()

SkARGB32_Black_Blitter::SkARGB32_Black_Blitter ( const SkPixmap &  device, const SkPaint &  paint  )

inline

Definition at line 104 of file SkCoreBlitters.h.

        : INHERITED(device, paint) {}

Member Function Documentation

blitAntiH()

void SkARGB32_Black_Blitter::blitAntiH ( int  x, int  y, const SkAlpha  antialias[], const int16_t  runs[]  )

overridevirtual

Blit a horizontal run of antialiased pixels; runs[] is a sparse zero-terminated run-length encoding of spans of constant alpha values. The runs[] and antialias[] work together to represent long runs of pixels with the same alphas. The runs[] contains the number of pixels with the same alpha, and antialias[] contain the coverage value for that number of pixels. The runs[] (and antialias[]) are encoded in a clever way. The runs array is zero terminated, and has enough entries for each pixel plus one, in most cases some of the entries will not contain valid data. An entry in the runs array contains the number of pixels (np) that have the same alpha value. The next np value is found np entries away. For example, if runs[0] = 7, then the next valid entry will by at runs[7]. The runs array and antialias[] are coupled by index. So, if the np entry is at runs[45] = 12 then the alpha value can be found at antialias[45] = 0x88. This would mean to use an alpha value of 0x88 for the next 12 pixels starting at pixel 45.

Implements SkBlitter.

Definition at line 1669 of file SkBlitter_ARGB32.cpp.

                                                             {
    uint32_t*   device = fDevice.writable_addr32(x, y);
    SkPMColor   black = (SkPMColor)(SK_A32_MASK << SK_A32_SHIFT);
 
    for (;;) {
        int count = runs[0];
        SkASSERT(count >= 0);
        if (count <= 0) {
            return;
        }
        unsigned aa = antialias[0];
        if (aa) {
            if (aa == 255) {
                SkOpts::memset32(device, black, count);
            } else {
                SkPMColor src = aa << SK_A32_SHIFT;
                unsigned dst_scale = 256 - aa;
                int n = count;
                do {
                    --n;
                    device[n] = src + SkAlphaMulQ(device[n], dst_scale);
                } while (n > 0);
            }
        }
        runs += count;
        antialias += count;
        device += count;
    }
}

blitAntiH2()

void SkARGB32_Black_Blitter::blitAntiH2 ( int  x, int  y, U8CPU  a0, U8CPU  a1  )

overridevirtual

Reimplemented from SkBlitter.

Definition at line 1700 of file SkBlitter_ARGB32.cpp.

                                                                        {
    uint32_t* device = fDevice.writable_addr32(x, y);
    SkDEBUGCODE((void)fDevice.writable_addr32(x + 1, y);)
 
    device[0] = (a0 << SK_A32_SHIFT) + SkAlphaMulQ(device[0], 256 - a0);
    device[1] = (a1 << SK_A32_SHIFT) + SkAlphaMulQ(device[1], 256 - a1);
}

blitAntiV2()

void SkARGB32_Black_Blitter::blitAntiV2 ( int  x, int  y, U8CPU  a0, U8CPU  a1  )

overridevirtual

Reimplemented from SkBlitter.

Definition at line 1708 of file SkBlitter_ARGB32.cpp.

                                                                        {
    uint32_t* device = fDevice.writable_addr32(x, y);
    SkDEBUGCODE((void)fDevice.writable_addr32(x, y + 1);)
 
    device[0] = (a0 << SK_A32_SHIFT) + SkAlphaMulQ(device[0], 256 - a0);
    device = (uint32_t*)((char*)device + fDevice.rowBytes());
    device[0] = (a1 << SK_A32_SHIFT) + SkAlphaMulQ(device[0], 256 - a1);
}

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

• third_party/skia/src/core/SkCoreBlitters.h
• third_party/skia/src/core/SkBlitter_ARGB32.cpp