SkARGB32_Shader_Blitter Class Reference

#include <SkCoreBlitters.h>

Inheritance diagram for SkARGB32_Shader_Blitter:

Public Member Functions
	SkARGB32_Shader_Blitter (const SkPixmap &device, const SkPaint &paint, SkShaderBase::Context *shaderContext)
	~SkARGB32_Shader_Blitter () override
void	blitH (int x, int y, int width) override
	Blit a horizontal run of one or more pixels.
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.
void	blitAntiH (int x, int y, const SkAlpha[], const int16_t[]) override
void	blitMask (const SkMask &, const SkIRect &) override
Public Member Functions inherited from SkShaderBlitter
	SkShaderBlitter (const SkPixmap &device, const SkPaint &paint, SkShaderBase::Context *shaderContext)
	~SkShaderBlitter () override
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 void	blitAntiH2 (int x, int y, U8CPU a0, U8CPU a1)
virtual void	blitAntiV2 (int x, int y, U8CPU a0, U8CPU a1)
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 SkShaderBlitter
sk_sp< SkShader >	fShader
SkShaderBase::Context *	fShaderContext
Protected Attributes inherited from SkRasterBlitter
const SkPixmap	fDevice
Protected Attributes inherited from SkBlitter
SkAutoMalloc	fBlitMemory

Detailed Description

Definition at line 114 of file SkCoreBlitters.h.

Constructor & Destructor Documentation

SkARGB32_Shader_Blitter()

SkARGB32_Shader_Blitter::SkARGB32_Shader_Blitter	(	const SkPixmap &	device,
		const SkPaint &	paint,
		SkShaderBase::Context *	shaderContext
	)

Definition at line 1719 of file SkBlitter_ARGB32.cpp.

    : INHERITED(device, paint, shaderContext)
{
    fBuffer = (SkPMColor*)sk_malloc_throw(device.width() * (sizeof(SkPMColor)));
 
    SkASSERT(paint.isSrcOver());
 
    int flags = 0;
    if (!(shaderContext->getFlags() & SkShaderBase::kOpaqueAlpha_Flag)) {
        flags |= SkBlitRow::kSrcPixelAlpha_Flag32;
    }
    // we call this on the output from the shader
    fProc32 = SkBlitRow::Factory32(flags);
    // we call this on the output from the shader + alpha from the aa buffer
    fProc32Blend = SkBlitRow::Factory32(flags | SkBlitRow::kGlobalAlpha_Flag32);
 
    fShadeDirectlyIntoDevice =
            SkToBool(shaderContext->getFlags() & SkShaderBase::kOpaqueAlpha_Flag);
}

~SkARGB32_Shader_Blitter()

SkARGB32_Shader_Blitter::~SkARGB32_Shader_Blitter ( )

override

Definition at line 1740 of file SkBlitter_ARGB32.cpp.

                                                  {
    sk_free(fBuffer);
}

Member Function Documentation

blitAntiH()

void SkARGB32_Shader_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 1784 of file SkBlitter_ARGB32.cpp.

                                                              {
    SkPMColor* span = fBuffer;
    uint32_t*  device = fDevice.writable_addr32(x, y);
    auto*      shaderContext = fShaderContext;
 
    if (fShadeDirectlyIntoDevice || (shaderContext->getFlags() & SkShaderBase::kOpaqueAlpha_Flag)) {
        for (;;) {
            int count = *runs;
            if (count <= 0) {
                break;
            }
            int aa = *antialias;
            if (aa) {
                if (aa == 255) {
                    // cool, have the shader draw right into the device
                    shaderContext->shadeSpan(x, y, device, count);
                } else {
                    shaderContext->shadeSpan(x, y, span, count);
                    fProc32Blend(device, span, count, aa);
                }
            }
            device += count;
            runs += count;
            antialias += count;
            x += count;
        }
    } else {
        for (;;) {
            int count = *runs;
            if (count <= 0) {
                break;
            }
            int aa = *antialias;
            if (aa) {
                shaderContext->shadeSpan(x, y, span, count);
                if (aa == 255) {
                    fProc32(device, span, count, 255);
                } else {
                    fProc32Blend(device, span, count, aa);
                }
            }
            device += count;
            runs += count;
            antialias += count;
            x += count;
        }
    }
}

blitH()

void SkARGB32_Shader_Blitter::blitH ( int  x, int  y, int  width  )

overridevirtual

Blit a horizontal run of one or more pixels.

Implements SkBlitter.

Definition at line 1744 of file SkBlitter_ARGB32.cpp.

                                                           {
    SkASSERT(x >= 0 && y >= 0 && x + width <= fDevice.width());
 
    uint32_t* device = fDevice.writable_addr32(x, y);
 
    if (fShadeDirectlyIntoDevice) {
        fShaderContext->shadeSpan(x, y, device, width);
    } else {
        SkPMColor*  span = fBuffer;
        fShaderContext->shadeSpan(x, y, span, width);
        fProc32(device, span, width, 255);
    }
}

blitMask()

void SkARGB32_Shader_Blitter::blitMask ( const SkMask &  mask, const SkIRect &  clip  )

overridevirtual

Blit a pattern of pixels defined by a rectangle-clipped mask; typically used for text.

Reimplemented from SkBlitter.

Definition at line 1957 of file SkBlitter_ARGB32.cpp.

                                                                              {
    SkASSERT(mask.fBounds.contains(clip));
 
    void (*blend_row)(SkPMColor*, const void* mask, const SkPMColor*, int) = nullptr;
 
    bool opaque = (fShaderContext->getFlags() & SkShaderBase::kOpaqueAlpha_Flag);
 
    if (mask.fFormat == SkMask::kA8_Format && opaque) {
        blend_row = blend_row_A8_opaque;
    } else if (mask.fFormat == SkMask::kA8_Format) {
        blend_row = blend_row_A8;
    } else if (mask.fFormat == SkMask::kLCD16_Format && opaque) {
        blend_row = blend_row_LCD16_opaque;
    } else if (mask.fFormat == SkMask::kLCD16_Format) {
        blend_row = blend_row_lcd16;
    } else {
        this->INHERITED::blitMask(mask, clip);
        return;
    }
 
    const int x = clip.fLeft;
    const int width = clip.width();
    int y = clip.fTop;
    int height = clip.height();
 
    char* dstRow = (char*)fDevice.writable_addr32(x, y);
    const size_t dstRB = fDevice.rowBytes();
    const uint8_t* maskRow = (const uint8_t*)mask.getAddr(x, y);
    const size_t maskRB = mask.fRowBytes;
 
    SkPMColor* span = fBuffer;
    SkASSERT(blend_row);
    do {
        fShaderContext->shadeSpan(x, y, span, width);
        blend_row(reinterpret_cast<SkPMColor*>(dstRow), maskRow, span, width);
        dstRow += dstRB;
        maskRow += maskRB;
        y += 1;
    } while (--height > 0);
}

blitRect()

void SkARGB32_Shader_Blitter::blitRect ( int  x, int  y, int  width, int  height  )

overridevirtual

Blit a solid rectangle one or more pixels wide.

Reimplemented from SkBlitter.

Definition at line 1758 of file SkBlitter_ARGB32.cpp.

                                                                          {
    SkASSERT(x >= 0 && y >= 0 &&
             x + width <= fDevice.width() && y + height <= fDevice.height());
 
    uint32_t*  device = fDevice.writable_addr32(x, y);
    size_t     deviceRB = fDevice.rowBytes();
    auto*      shaderContext = fShaderContext;
    SkPMColor* span = fBuffer;
 
    if (fShadeDirectlyIntoDevice) {
        do {
            shaderContext->shadeSpan(x, y, device, width);
            y += 1;
            device = (uint32_t*)((char*)device + deviceRB);
        } while (--height > 0);
    } else {
        SkBlitRow::Proc32 proc = fProc32;
        do {
            shaderContext->shadeSpan(x, y, span, width);
            proc(device, span, width, 255);
            y += 1;
            device = (uint32_t*)((char*)device + deviceRB);
        } while (--height > 0);
    }
}

blitV()

void SkARGB32_Shader_Blitter::blitV ( int  x, int  y, int  height, SkAlpha  alpha  )

overridevirtual

Blit a vertical run of pixels with a constant alpha value.

Reimplemented from SkBlitter.

Definition at line 1998 of file SkBlitter_ARGB32.cpp.

                                                                           {
    SkASSERT(x >= 0 && y >= 0 && y + height <= fDevice.height());
 
    uint32_t* device = fDevice.writable_addr32(x, y);
    size_t    deviceRB = fDevice.rowBytes();
 
    if (fShadeDirectlyIntoDevice) {
        if (255 == alpha) {
            do {
                fShaderContext->shadeSpan(x, y, device, 1);
                y += 1;
                device = (uint32_t*)((char*)device + deviceRB);
            } while (--height > 0);
        } else {
            do {
                SkPMColor c;
                fShaderContext->shadeSpan(x, y, &c, 1);
                *device = SkFourByteInterp(c, *device, alpha);
                y += 1;
                device = (uint32_t*)((char*)device + deviceRB);
            } while (--height > 0);
        }
    } else {
        SkPMColor* span = fBuffer;
        SkBlitRow::Proc32 proc = (255 == alpha) ? fProc32 : fProc32Blend;
        do {
            fShaderContext->shadeSpan(x, y, span, 1);
            proc(device, span, 1, alpha);
            y += 1;
            device = (uint32_t*)((char*)device + deviceRB);
        } while (--height > 0);
    }
}

---

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