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/*
* Copyright (C) 2006 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "SkXfermode.h"
#include "SkColorPriv.h"
#define SkAlphaMulAlpha(a, b) SkMulDiv255Round(a, b)
static SkPMColor SkFourByteInterp(SkPMColor src, SkPMColor dst, U8CPU alpha) {
unsigned scale = SkAlpha255To256(alpha);
unsigned a = SkAlphaBlend(SkGetPackedA32(src), SkGetPackedA32(dst), scale);
unsigned r = SkAlphaBlend(SkGetPackedR32(src), SkGetPackedR32(dst), scale);
unsigned g = SkAlphaBlend(SkGetPackedG32(src), SkGetPackedG32(dst), scale);
unsigned b = SkAlphaBlend(SkGetPackedB32(src), SkGetPackedB32(dst), scale);
return SkPackARGB32(a, r, g, b);
}
#if 0
// idea for higher precision blends in xfer procs (and slightly faster)
// see DstATop as a probable caller
static U8CPU mulmuldiv255round(U8CPU a, U8CPU b, U8CPU c, U8CPU d) {
SkASSERT(a <= 255);
SkASSERT(b <= 255);
SkASSERT(c <= 255);
SkASSERT(d <= 255);
unsigned prod = SkMulS16(a, b) + SkMulS16(c, d) + 128;
unsigned result = (prod + (prod >> 8)) >> 8;
SkASSERT(result <= 255);
return result;
}
#endif
static inline unsigned saturated_add(unsigned a, unsigned b) {
SkASSERT(a <= 255);
SkASSERT(b <= 255);
unsigned sum = a + b;
if (sum > 255) {
sum = 255;
}
return sum;
}
static inline int clamp_signed_byte(int n) {
if (n < 0) {
n = 0;
} else if (n > 255) {
n = 255;
}
return n;
}
static inline int clamp_div255round(int prod) {
if (prod <= 0) {
return 0;
} else if (prod >= 255*255) {
return 255;
} else {
return SkDiv255Round(prod);
}
}
static inline int clamp_max(int value, int max) {
if (value > max) {
value = max;
}
return value;
}
///////////////////////////////////////////////////////////////////////////////
bool SkXfermode::asCoeff(Coeff* src, Coeff* dst) {
return false;
}
SkPMColor SkXfermode::xferColor(SkPMColor src, SkPMColor dst) {
// no-op. subclasses should override this
return dst;
}
void SkXfermode::xfer32(SK_RESTRICT SkPMColor dst[],
const SK_RESTRICT SkPMColor src[], int count,
const SK_RESTRICT SkAlpha aa[]) {
SkASSERT(dst && src && count >= 0);
if (NULL == aa) {
for (int i = count - 1; i >= 0; --i) {
dst[i] = this->xferColor(src[i], dst[i]);
}
} else {
for (int i = count - 1; i >= 0; --i) {
unsigned a = aa[i];
if (0 != a) {
SkPMColor dstC = dst[i];
SkPMColor C = this->xferColor(src[i], dstC);
if (0xFF != a) {
C = SkFourByteInterp(C, dstC, a);
}
dst[i] = C;
}
}
}
}
void SkXfermode::xfer16(SK_RESTRICT uint16_t dst[],
const SK_RESTRICT SkPMColor src[], int count,
const SK_RESTRICT SkAlpha aa[]) {
SkASSERT(dst && src && count >= 0);
if (NULL == aa) {
for (int i = count - 1; i >= 0; --i) {
SkPMColor dstC = SkPixel16ToPixel32(dst[i]);
dst[i] = SkPixel32ToPixel16_ToU16(this->xferColor(src[i], dstC));
}
} else {
for (int i = count - 1; i >= 0; --i) {
unsigned a = aa[i];
if (0 != a) {
SkPMColor dstC = SkPixel16ToPixel32(dst[i]);
SkPMColor C = this->xferColor(src[i], dstC);
if (0xFF != a) {
C = SkFourByteInterp(C, dstC, a);
}
dst[i] = SkPixel32ToPixel16_ToU16(C);
}
}
}
}
void SkXfermode::xfer4444(SK_RESTRICT SkPMColor16 dst[],
const SK_RESTRICT SkPMColor src[], int count,
const SK_RESTRICT SkAlpha aa[])
{
SkASSERT(dst && src && count >= 0);
if (NULL == aa) {
for (int i = count - 1; i >= 0; --i) {
SkPMColor dstC = SkPixel4444ToPixel32(dst[i]);
dst[i] = SkPixel32ToPixel4444(this->xferColor(src[i], dstC));
}
} else {
for (int i = count - 1; i >= 0; --i) {
unsigned a = aa[i];
if (0 != a) {
SkPMColor dstC = SkPixel4444ToPixel32(dst[i]);
SkPMColor C = this->xferColor(src[i], dstC);
if (0xFF != a) {
C = SkFourByteInterp(C, dstC, a);
}
dst[i] = SkPixel32ToPixel4444(C);
}
}
}
}
void SkXfermode::xferA8(SK_RESTRICT SkAlpha dst[],
const SkPMColor src[], int count,
const SK_RESTRICT SkAlpha aa[])
{
SkASSERT(dst && src && count >= 0);
if (NULL == aa) {
for (int i = count - 1; i >= 0; --i) {
SkPMColor res = this->xferColor(src[i], (dst[i] << SK_A32_SHIFT));
dst[i] = SkToU8(SkGetPackedA32(res));
}
} else {
for (int i = count - 1; i >= 0; --i) {
unsigned a = aa[i];
if (0 != a) {
SkAlpha dstA = dst[i];
unsigned A = SkGetPackedA32(this->xferColor(src[i],
(SkPMColor)(dstA << SK_A32_SHIFT)));
if (0xFF != a) {
A = SkAlphaBlend(A, dstA, SkAlpha255To256(a));
}
dst[i] = SkToU8(A);
}
}
}
}
///////////////////////////////////////////////////////////////////////////////
void SkProcXfermode::xfer32(SK_RESTRICT SkPMColor dst[],
const SK_RESTRICT SkPMColor src[], int count,
const SK_RESTRICT SkAlpha aa[]) {
SkASSERT(dst && src && count >= 0);
SkXfermodeProc proc = fProc;
if (NULL != proc) {
if (NULL == aa) {
for (int i = count - 1; i >= 0; --i) {
dst[i] = proc(src[i], dst[i]);
}
} else {
for (int i = count - 1; i >= 0; --i) {
unsigned a = aa[i];
if (0 != a) {
SkPMColor dstC = dst[i];
SkPMColor C = proc(src[i], dstC);
if (a != 0xFF) {
C = SkFourByteInterp(C, dstC, a);
}
dst[i] = C;
}
}
}
}
}
void SkProcXfermode::xfer16(SK_RESTRICT uint16_t dst[],
const SK_RESTRICT SkPMColor src[], int count,
const SK_RESTRICT SkAlpha aa[]) {
SkASSERT(dst && src && count >= 0);
SkXfermodeProc proc = fProc;
if (NULL != proc) {
if (NULL == aa) {
for (int i = count - 1; i >= 0; --i) {
SkPMColor dstC = SkPixel16ToPixel32(dst[i]);
dst[i] = SkPixel32ToPixel16_ToU16(proc(src[i], dstC));
}
} else {
for (int i = count - 1; i >= 0; --i) {
unsigned a = aa[i];
if (0 != a) {
SkPMColor dstC = SkPixel16ToPixel32(dst[i]);
SkPMColor C = proc(src[i], dstC);
if (0xFF != a) {
C = SkFourByteInterp(C, dstC, a);
}
dst[i] = SkPixel32ToPixel16_ToU16(C);
}
}
}
}
}
void SkProcXfermode::xfer4444(SK_RESTRICT SkPMColor16 dst[],
const SK_RESTRICT SkPMColor src[], int count,
const SK_RESTRICT SkAlpha aa[]) {
SkASSERT(dst && src && count >= 0);
SkXfermodeProc proc = fProc;
if (NULL != proc) {
if (NULL == aa) {
for (int i = count - 1; i >= 0; --i) {
SkPMColor dstC = SkPixel4444ToPixel32(dst[i]);
dst[i] = SkPixel32ToPixel4444(proc(src[i], dstC));
}
} else {
for (int i = count - 1; i >= 0; --i) {
unsigned a = aa[i];
if (0 != a) {
SkPMColor dstC = SkPixel4444ToPixel32(dst[i]);
SkPMColor C = proc(src[i], dstC);
if (0xFF != a) {
C = SkFourByteInterp(C, dstC, a);
}
dst[i] = SkPixel32ToPixel4444(C);
}
}
}
}
}
void SkProcXfermode::xferA8(SK_RESTRICT SkAlpha dst[],
const SK_RESTRICT SkPMColor src[], int count,
const SK_RESTRICT SkAlpha aa[]) {
SkASSERT(dst && src && count >= 0);
SkXfermodeProc proc = fProc;
if (NULL != proc) {
if (NULL == aa) {
for (int i = count - 1; i >= 0; --i) {
SkPMColor res = proc(src[i], dst[i] << SK_A32_SHIFT);
dst[i] = SkToU8(SkGetPackedA32(res));
}
} else {
for (int i = count - 1; i >= 0; --i) {
unsigned a = aa[i];
if (0 != a) {
SkAlpha dstA = dst[i];
SkPMColor res = proc(src[i], dstA << SK_A32_SHIFT);
unsigned A = SkGetPackedA32(res);
if (0xFF != a) {
A = SkAlphaBlend(A, dstA, SkAlpha255To256(a));
}
dst[i] = SkToU8(A);
}
}
}
}
}
SkProcXfermode::SkProcXfermode(SkFlattenableReadBuffer& buffer)
: SkXfermode(buffer) {
fProc = (SkXfermodeProc)buffer.readFunctionPtr();
}
void SkProcXfermode::flatten(SkFlattenableWriteBuffer& buffer) {
buffer.writeFunctionPtr((void*)fProc);
}
///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////
class SkProcCoeffXfermode : public SkProcXfermode {
public:
SkProcCoeffXfermode(SkXfermodeProc proc, Coeff sc, Coeff dc)
: INHERITED(proc), fSrcCoeff(sc), fDstCoeff(dc) {
}
virtual bool asCoeff(Coeff* sc, Coeff* dc) {
if (sc) {
*sc = fSrcCoeff;
}
if (dc) {
*dc = fDstCoeff;
}
return true;
}
virtual Factory getFactory() { return CreateProc; }
virtual void flatten(SkFlattenableWriteBuffer& buffer) {
this->INHERITED::flatten(buffer);
buffer.write32(fSrcCoeff);
buffer.write32(fDstCoeff);
}
protected:
SkProcCoeffXfermode(SkFlattenableReadBuffer& buffer)
: INHERITED(buffer) {
fSrcCoeff = (Coeff)buffer.readU32();
fDstCoeff = (Coeff)buffer.readU32();
}
private:
Coeff fSrcCoeff, fDstCoeff;
static SkFlattenable* CreateProc(SkFlattenableReadBuffer& buffer) {
return SkNEW_ARGS(SkProcCoeffXfermode, (buffer)); }
typedef SkProcXfermode INHERITED;
};
///////////////////////////////////////////////////////////////////////////////
// kClear_Mode, //!< [0, 0]
static SkPMColor clear_modeproc(SkPMColor src, SkPMColor dst) {
return 0;
}
// kSrc_Mode, //!< [Sa, Sc]
static SkPMColor src_modeproc(SkPMColor src, SkPMColor dst) {
return src;
}
// kDst_Mode, //!< [Da, Dc]
static SkPMColor dst_modeproc(SkPMColor src, SkPMColor dst) {
return dst;
}
// kSrcOver_Mode, //!< [Sa + Da - Sa*Da, Sc + (1 - Sa)*Dc]
static SkPMColor srcover_modeproc(SkPMColor src, SkPMColor dst) {
#if 0
// this is the old, more-correct way, but it doesn't guarantee that dst==255
// will always stay opaque
return src + SkAlphaMulQ(dst, SkAlpha255To256(255 - SkGetPackedA32(src)));
#else
// this is slightly faster, but more importantly guarantees that dst==255
// will always stay opaque
return src + SkAlphaMulQ(dst, 256 - SkGetPackedA32(src));
#endif
}
// kDstOver_Mode, //!< [Sa + Da - Sa*Da, Dc + (1 - Da)*Sc]
static SkPMColor dstover_modeproc(SkPMColor src, SkPMColor dst) {
// this is the reverse of srcover, just flipping src and dst
// see srcover's comment about the 256 for opaqueness guarantees
return dst + SkAlphaMulQ(src, 256 - SkGetPackedA32(dst));
}
// kSrcIn_Mode, //!< [Sa * Da, Sc * Da]
static SkPMColor srcin_modeproc(SkPMColor src, SkPMColor dst) {
return SkAlphaMulQ(src, SkAlpha255To256(SkGetPackedA32(dst)));
}
// kDstIn_Mode, //!< [Sa * Da, Sa * Dc]
static SkPMColor dstin_modeproc(SkPMColor src, SkPMColor dst) {
return SkAlphaMulQ(dst, SkAlpha255To256(SkGetPackedA32(src)));
}
// kSrcOut_Mode, //!< [Sa * (1 - Da), Sc * (1 - Da)]
static SkPMColor srcout_modeproc(SkPMColor src, SkPMColor dst) {
return SkAlphaMulQ(src, SkAlpha255To256(255 - SkGetPackedA32(dst)));
}
// kDstOut_Mode, //!< [Da * (1 - Sa), Dc * (1 - Sa)]
static SkPMColor dstout_modeproc(SkPMColor src, SkPMColor dst) {
return SkAlphaMulQ(dst, SkAlpha255To256(255 - SkGetPackedA32(src)));
}
// kSrcATop_Mode, //!< [Da, Sc * Da + (1 - Sa) * Dc]
static SkPMColor srcatop_modeproc(SkPMColor src, SkPMColor dst) {
unsigned sa = SkGetPackedA32(src);
unsigned da = SkGetPackedA32(dst);
unsigned isa = 255 - sa;
return SkPackARGB32(da,
SkAlphaMulAlpha(da, SkGetPackedR32(src)) +
SkAlphaMulAlpha(isa, SkGetPackedR32(dst)),
SkAlphaMulAlpha(da, SkGetPackedG32(src)) +
SkAlphaMulAlpha(isa, SkGetPackedG32(dst)),
SkAlphaMulAlpha(da, SkGetPackedB32(src)) +
SkAlphaMulAlpha(isa, SkGetPackedB32(dst)));
}
// kDstATop_Mode, //!< [Sa, Sa * Dc + Sc * (1 - Da)]
static SkPMColor dstatop_modeproc(SkPMColor src, SkPMColor dst) {
unsigned sa = SkGetPackedA32(src);
unsigned da = SkGetPackedA32(dst);
unsigned ida = 255 - da;
return SkPackARGB32(sa,
SkAlphaMulAlpha(ida, SkGetPackedR32(src)) +
SkAlphaMulAlpha(sa, SkGetPackedR32(dst)),
SkAlphaMulAlpha(ida, SkGetPackedG32(src)) +
SkAlphaMulAlpha(sa, SkGetPackedG32(dst)),
SkAlphaMulAlpha(ida, SkGetPackedB32(src)) +
SkAlphaMulAlpha(sa, SkGetPackedB32(dst)));
}
// kXor_Mode [Sa + Da - 2 * Sa * Da, Sc * (1 - Da) + (1 - Sa) * Dc]
static SkPMColor xor_modeproc(SkPMColor src, SkPMColor dst) {
unsigned sa = SkGetPackedA32(src);
unsigned da = SkGetPackedA32(dst);
unsigned isa = 255 - sa;
unsigned ida = 255 - da;
return SkPackARGB32(sa + da - (SkAlphaMulAlpha(sa, da) << 1),
SkAlphaMulAlpha(ida, SkGetPackedR32(src)) +
SkAlphaMulAlpha(isa, SkGetPackedR32(dst)),
SkAlphaMulAlpha(ida, SkGetPackedG32(src)) +
SkAlphaMulAlpha(isa, SkGetPackedG32(dst)),
SkAlphaMulAlpha(ida, SkGetPackedB32(src)) +
SkAlphaMulAlpha(isa, SkGetPackedB32(dst)));
}
///////////////////////////////////////////////////////////////////////////////
// kPlus_Mode
static SkPMColor plus_modeproc(SkPMColor src, SkPMColor dst) {
unsigned b = saturated_add(SkGetPackedB32(src), SkGetPackedB32(dst));
unsigned g = saturated_add(SkGetPackedG32(src), SkGetPackedG32(dst));
unsigned r = saturated_add(SkGetPackedR32(src), SkGetPackedR32(dst));
unsigned a = saturated_add(SkGetPackedA32(src), SkGetPackedA32(dst));
return SkPackARGB32(a, r, g, b);
}
// kMultiply_Mode
static SkPMColor multiply_modeproc(SkPMColor src, SkPMColor dst) {
int a = SkAlphaMulAlpha(SkGetPackedA32(src), SkGetPackedA32(dst));
int r = SkAlphaMulAlpha(SkGetPackedR32(src), SkGetPackedR32(dst));
int g = SkAlphaMulAlpha(SkGetPackedG32(src), SkGetPackedG32(dst));
int b = SkAlphaMulAlpha(SkGetPackedB32(src), SkGetPackedB32(dst));
return SkPackARGB32(a, r, g, b);
}
// kScreen_Mode
static inline int srcover_byte(int a, int b) {
return a + b - SkAlphaMulAlpha(a, b);
}
static SkPMColor screen_modeproc(SkPMColor src, SkPMColor dst) {
int a = srcover_byte(SkGetPackedA32(src), SkGetPackedA32(dst));
int r = srcover_byte(SkGetPackedR32(src), SkGetPackedR32(dst));
int g = srcover_byte(SkGetPackedG32(src), SkGetPackedG32(dst));
int b = srcover_byte(SkGetPackedB32(src), SkGetPackedB32(dst));
return SkPackARGB32(a, r, g, b);
}
// kOverlay_Mode
static inline int overlay_byte(int sc, int dc, int sa, int da) {
int tmp = sc * (255 - da) + dc * (255 - sa);
int rc;
if (2 * dc <= da) {
rc = 2 * sc * dc;
} else {
rc = sa * da - 2 * (da - dc) * (sa - sc);
}
return clamp_div255round(rc + tmp);
}
static SkPMColor overlay_modeproc(SkPMColor src, SkPMColor dst) {
int sa = SkGetPackedA32(src);
int da = SkGetPackedA32(dst);
int a = srcover_byte(sa, da);
int r = overlay_byte(SkGetPackedR32(src), SkGetPackedR32(dst), sa, da);
int g = overlay_byte(SkGetPackedG32(src), SkGetPackedG32(dst), sa, da);
int b = overlay_byte(SkGetPackedB32(src), SkGetPackedB32(dst), sa, da);
return SkPackARGB32(a, r, g, b);
}
// kDarken_Mode
static inline int darken_byte(int sc, int dc, int sa, int da) {
int sd = sc * da;
int ds = dc * sa;
if (sd < ds) {
// srcover
return sc + dc - SkDiv255Round(ds);
} else {
// dstover
return dc + sc - SkDiv255Round(sd);
}
}
static SkPMColor darken_modeproc(SkPMColor src, SkPMColor dst) {
int sa = SkGetPackedA32(src);
int da = SkGetPackedA32(dst);
int a = srcover_byte(sa, da);
int r = darken_byte(SkGetPackedR32(src), SkGetPackedR32(dst), sa, da);
int g = darken_byte(SkGetPackedG32(src), SkGetPackedG32(dst), sa, da);
int b = darken_byte(SkGetPackedB32(src), SkGetPackedB32(dst), sa, da);
return SkPackARGB32(a, r, g, b);
}
// kLighten_Mode
static inline int lighten_byte(int sc, int dc, int sa, int da) {
int sd = sc * da;
int ds = dc * sa;
if (sd > ds) {
// srcover
return sc + dc - SkDiv255Round(ds);
} else {
// dstover
return dc + sc - SkDiv255Round(sd);
}
}
static SkPMColor lighten_modeproc(SkPMColor src, SkPMColor dst) {
int sa = SkGetPackedA32(src);
int da = SkGetPackedA32(dst);
int a = srcover_byte(sa, da);
int r = lighten_byte(SkGetPackedR32(src), SkGetPackedR32(dst), sa, da);
int g = lighten_byte(SkGetPackedG32(src), SkGetPackedG32(dst), sa, da);
int b = lighten_byte(SkGetPackedB32(src), SkGetPackedB32(dst), sa, da);
return SkPackARGB32(a, r, g, b);
}
// kColorDodge_Mode
static inline int colordodge_byte(int sc, int dc, int sa, int da) {
int diff = sa - sc;
int rc;
if (0 == diff) {
rc = sa * da + sc * (255 - da) + dc * (255 - sa);
rc = SkDiv255Round(rc);
} else {
int tmp = (dc * sa << 15) / (da * diff);
rc = SkDiv255Round(sa * da) * tmp >> 15;
// don't clamp here, since we'll do it in our modeproc
}
return rc;
}
static SkPMColor colordodge_modeproc(SkPMColor src, SkPMColor dst) {
// added to avoid div-by-zero in colordodge_byte
if (0 == dst) {
return src;
}
int sa = SkGetPackedA32(src);
int da = SkGetPackedA32(dst);
int a = srcover_byte(sa, da);
int r = colordodge_byte(SkGetPackedR32(src), SkGetPackedR32(dst), sa, da);
int g = colordodge_byte(SkGetPackedG32(src), SkGetPackedG32(dst), sa, da);
int b = colordodge_byte(SkGetPackedB32(src), SkGetPackedB32(dst), sa, da);
r = clamp_max(r, a);
g = clamp_max(g, a);
b = clamp_max(b, a);
return SkPackARGB32(a, r, g, b);
}
// kColorBurn_Mode
static inline int colorburn_byte(int sc, int dc, int sa, int da) {
int rc;
if (dc == da && 0 == sc) {
rc = sa * da + dc * (255 - sa);
} else if (0 == sc) {
return SkAlphaMulAlpha(dc, 255 - sa);
} else {
int tmp = (sa * (da - dc) * 256) / (sc * da);
if (tmp > 256) {
tmp = 256;
}
int tmp2 = sa * da;
rc = tmp2 - (tmp2 * tmp >> 8) + sc * (255 - da) + dc * (255 - sa);
}
return SkDiv255Round(rc);
}
static SkPMColor colorburn_modeproc(SkPMColor src, SkPMColor dst) {
// added to avoid div-by-zero in colorburn_byte
if (0 == dst) {
return src;
}
int sa = SkGetPackedA32(src);
int da = SkGetPackedA32(dst);
int a = srcover_byte(sa, da);
int r = colorburn_byte(SkGetPackedR32(src), SkGetPackedR32(dst), sa, da);
int g = colorburn_byte(SkGetPackedG32(src), SkGetPackedG32(dst), sa, da);
int b = colorburn_byte(SkGetPackedB32(src), SkGetPackedB32(dst), sa, da);
return SkPackARGB32(a, r, g, b);
}
// kHardLight_Mode
static inline int hardlight_byte(int sc, int dc, int sa, int da) {
int rc;
if (2 * sc <= sa) {
rc = 2 * sc * dc;
} else {
rc = sa * da - 2 * (da - dc) * (sa - sc);
}
return clamp_div255round(rc + sc * (255 - da) + dc * (255 - sa));
}
static SkPMColor hardlight_modeproc(SkPMColor src, SkPMColor dst) {
int sa = SkGetPackedA32(src);
int da = SkGetPackedA32(dst);
int a = srcover_byte(sa, da);
int r = hardlight_byte(SkGetPackedR32(src), SkGetPackedR32(dst), sa, da);
int g = hardlight_byte(SkGetPackedG32(src), SkGetPackedG32(dst), sa, da);
int b = hardlight_byte(SkGetPackedB32(src), SkGetPackedB32(dst), sa, da);
return SkPackARGB32(a, r, g, b);
}
// returns 255 * sqrt(n/255)
static U8CPU sqrt_unit_byte(U8CPU n) {
return SkSqrtBits(n, 15+4);
}
// kSoftLight_Mode
static inline int softlight_byte(int sc, int dc, int sa, int da) {
int m = da ? dc * 256 / da : 0;
int rc;
if (2 * sc <= sa) {
rc = dc * (sa + ((2 * sc - sa) * (256 - m) >> 8));
} else if (4 * dc <= da) {
int tmp = (4 * m * (4 * m + 256) * (m - 256) >> 16) + 7 * m;
rc = dc * sa + (da * (2 * sc - sa) * tmp >> 8);
} else {
int tmp = sqrt_unit_byte(m) - m;
rc = dc * sa + (da * (2 * sc - sa) * tmp >> 8);
}
return clamp_div255round(rc + sc * (255 - da) + dc * (255 - sa));
}
static SkPMColor softlight_modeproc(SkPMColor src, SkPMColor dst) {
int sa = SkGetPackedA32(src);
int da = SkGetPackedA32(dst);
int a = srcover_byte(sa, da);
int r = softlight_byte(SkGetPackedR32(src), SkGetPackedR32(dst), sa, da);
int g = softlight_byte(SkGetPackedG32(src), SkGetPackedG32(dst), sa, da);
int b = softlight_byte(SkGetPackedB32(src), SkGetPackedB32(dst), sa, da);
return SkPackARGB32(a, r, g, b);
}
// kDifference_Mode
static inline int difference_byte(int sc, int dc, int sa, int da) {
int tmp = SkMin32(sc * da, dc * sa);
return clamp_signed_byte(sc + dc - 2 * SkDiv255Round(tmp));
}
static SkPMColor difference_modeproc(SkPMColor src, SkPMColor dst) {
int sa = SkGetPackedA32(src);
int da = SkGetPackedA32(dst);
int a = srcover_byte(sa, da);
int r = difference_byte(SkGetPackedR32(src), SkGetPackedR32(dst), sa, da);
int g = difference_byte(SkGetPackedG32(src), SkGetPackedG32(dst), sa, da);
int b = difference_byte(SkGetPackedB32(src), SkGetPackedB32(dst), sa, da);
return SkPackARGB32(a, r, g, b);
}
// kExclusion_Mode
static inline int exclusion_byte(int sc, int dc, int sa, int da) {
// this equations is wacky, wait for SVG to confirm it
int r = sc * da + dc * sa - 2 * sc * dc + sc * (255 - da) + dc * (255 - sa);
return clamp_div255round(r);
}
static SkPMColor exclusion_modeproc(SkPMColor src, SkPMColor dst) {
int sa = SkGetPackedA32(src);
int da = SkGetPackedA32(dst);
int a = srcover_byte(sa, da);
int r = exclusion_byte(SkGetPackedR32(src), SkGetPackedR32(dst), sa, da);
int g = exclusion_byte(SkGetPackedG32(src), SkGetPackedG32(dst), sa, da);
int b = exclusion_byte(SkGetPackedB32(src), SkGetPackedB32(dst), sa, da);
return SkPackARGB32(a, r, g, b);
}
///////////////////////////////////////////////////////////////////////////////
class SkClearXfermode : public SkProcCoeffXfermode {
public:
SkClearXfermode() : SkProcCoeffXfermode(clear_modeproc,
kZero_Coeff, kZero_Coeff) {}
virtual void xfer32(SK_RESTRICT SkPMColor dst[],
const SK_RESTRICT SkPMColor[], int count,
const SK_RESTRICT SkAlpha aa[]) {
SkASSERT(dst && count >= 0);
if (NULL == aa) {
memset(dst, 0, count << 2);
} else {
for (int i = count - 1; i >= 0; --i) {
unsigned a = aa[i];
if (0xFF == a) {
dst[i] = 0;
} else if (a != 0) {
dst[i] = SkAlphaMulQ(dst[i], SkAlpha255To256(255 - a));
}
}
}
}
virtual void xferA8(SK_RESTRICT SkAlpha dst[],
const SK_RESTRICT SkPMColor[], int count,
const SK_RESTRICT SkAlpha aa[]) {
SkASSERT(dst && count >= 0);
if (NULL == aa) {
memset(dst, 0, count);
} else {
for (int i = count - 1; i >= 0; --i) {
unsigned a = aa[i];
if (0xFF == a) {
dst[i] = 0;
} else if (0 != a) {
dst[i] = SkAlphaMulAlpha(dst[i], 255 - a);
}
}
}
}
virtual Factory getFactory() { return CreateProc; }
private:
SkClearXfermode(SkFlattenableReadBuffer& buffer)
: SkProcCoeffXfermode(buffer) {}
static SkFlattenable* CreateProc(SkFlattenableReadBuffer& buffer) {
return SkNEW_ARGS(SkClearXfermode, (buffer));
}
};
///////////////////////////////////////////////////////////////////////////////
class SkSrcXfermode : public SkProcCoeffXfermode {
public:
SkSrcXfermode() : SkProcCoeffXfermode(src_modeproc,
kOne_Coeff, kZero_Coeff) {}
virtual void xfer32(SK_RESTRICT SkPMColor dst[],
const SK_RESTRICT SkPMColor src[], int count,
const SK_RESTRICT SkAlpha aa[]) {
SkASSERT(dst && src && count >= 0);
if (NULL == aa) {
memcpy(dst, src, count << 2);
} else {
for (int i = count - 1; i >= 0; --i) {
unsigned a = aa[i];
if (a == 0xFF) {
dst[i] = src[i];
} else if (a != 0) {
dst[i] = SkFourByteInterp(src[i], dst[i], a);
}
}
}
}
virtual void xferA8(SK_RESTRICT SkAlpha dst[],
const SK_RESTRICT SkPMColor src[], int count,
const SK_RESTRICT SkAlpha aa[]) {
SkASSERT(dst && src && count >= 0);
if (NULL == aa) {
for (int i = count - 1; i >= 0; --i) {
dst[i] = SkToU8(SkGetPackedA32(src[i]));
}
} else {
for (int i = count - 1; i >= 0; --i) {
unsigned a = aa[i];
if (0 != a) {
unsigned srcA = SkGetPackedA32(src[i]);
if (a == 0xFF) {
dst[i] = SkToU8(srcA);
} else {
dst[i] = SkToU8(SkAlphaBlend(srcA, dst[i], a));
}
}
}
}
}
virtual Factory getFactory() { return CreateProc; }
private:
SkSrcXfermode(SkFlattenableReadBuffer& buffer)
: SkProcCoeffXfermode(buffer) {}
static SkFlattenable* CreateProc(SkFlattenableReadBuffer& buffer) {
return SkNEW_ARGS(SkSrcXfermode, (buffer));
}
};
class SkDstInXfermode : public SkProcCoeffXfermode {
public:
SkDstInXfermode() : SkProcCoeffXfermode(dstin_modeproc,
kZero_Coeff, kSA_Coeff) {}
virtual void xfer32(SK_RESTRICT SkPMColor dst[],
const SK_RESTRICT SkPMColor src[], int count,
const SK_RESTRICT SkAlpha aa[]) {
SkASSERT(dst && src);
if (count <= 0) {
return;
}
if (NULL != aa) {
return this->INHERITED::xfer32(dst, src, count, aa);
}
do {
unsigned a = SkGetPackedA32(*src);
*dst = SkAlphaMulQ(*dst, SkAlpha255To256(a));
dst++;
src++;
} while (--count != 0);
}
virtual Factory getFactory() { return CreateProc; }
private:
SkDstInXfermode(SkFlattenableReadBuffer& buffer) : INHERITED(buffer) {}
static SkFlattenable* CreateProc(SkFlattenableReadBuffer& buffer) {
return SkNEW_ARGS(SkDstInXfermode, (buffer));
}
typedef SkProcCoeffXfermode INHERITED;
};
class SkDstOutXfermode : public SkProcCoeffXfermode {
public:
SkDstOutXfermode() : SkProcCoeffXfermode(dstout_modeproc,
kZero_Coeff, kISA_Coeff) {}
virtual void xfer32(SK_RESTRICT SkPMColor dst[],
const SK_RESTRICT SkPMColor src[], int count,
const SK_RESTRICT SkAlpha aa[]) {
SkASSERT(dst && src);
if (count <= 0) {
return;
}
if (NULL != aa) {
return this->INHERITED::xfer32(dst, src, count, aa);
}
do {
unsigned a = SkGetPackedA32(*src);
*dst = SkAlphaMulQ(*dst, SkAlpha255To256(255 - a));
dst++;
src++;
} while (--count != 0);
}
virtual Factory getFactory() { return CreateProc; }
private:
SkDstOutXfermode(SkFlattenableReadBuffer& buffer)
: INHERITED(buffer) {}
static SkFlattenable* CreateProc(SkFlattenableReadBuffer& buffer) {
return SkNEW_ARGS(SkDstOutXfermode, (buffer));
}
typedef SkProcCoeffXfermode INHERITED;
};
///////////////////////////////////////////////////////////////////////////////
struct ProcCoeff {
SkXfermodeProc fProc;
SkXfermode::Coeff fSC;
SkXfermode::Coeff fDC;
};
#define CANNOT_USE_COEFF SkXfermode::Coeff(-1)
static const ProcCoeff gProcCoeffs[] = {
{ clear_modeproc, SkXfermode::kZero_Coeff, SkXfermode::kZero_Coeff },
{ src_modeproc, SkXfermode::kOne_Coeff, SkXfermode::kZero_Coeff },
{ dst_modeproc, SkXfermode::kZero_Coeff, SkXfermode::kOne_Coeff },
{ srcover_modeproc, SkXfermode::kOne_Coeff, SkXfermode::kISA_Coeff },
{ dstover_modeproc, SkXfermode::kIDA_Coeff, SkXfermode::kOne_Coeff },
{ srcin_modeproc, SkXfermode::kDA_Coeff, SkXfermode::kZero_Coeff },
{ dstin_modeproc, SkXfermode::kZero_Coeff, SkXfermode::kSA_Coeff },
{ srcout_modeproc, SkXfermode::kIDA_Coeff, SkXfermode::kZero_Coeff },
{ dstout_modeproc, SkXfermode::kZero_Coeff, SkXfermode::kISA_Coeff },
{ srcatop_modeproc, SkXfermode::kDA_Coeff, SkXfermode::kISA_Coeff },
{ dstatop_modeproc, SkXfermode::kIDA_Coeff, SkXfermode::kSA_Coeff },
{ xor_modeproc, SkXfermode::kIDA_Coeff, SkXfermode::kISA_Coeff },
{ plus_modeproc, CANNOT_USE_COEFF, CANNOT_USE_COEFF },
{ multiply_modeproc, CANNOT_USE_COEFF, CANNOT_USE_COEFF },
{ screen_modeproc, CANNOT_USE_COEFF, CANNOT_USE_COEFF },
{ overlay_modeproc, CANNOT_USE_COEFF, CANNOT_USE_COEFF },
{ darken_modeproc, CANNOT_USE_COEFF, CANNOT_USE_COEFF },
{ lighten_modeproc, CANNOT_USE_COEFF, CANNOT_USE_COEFF },
{ colordodge_modeproc, CANNOT_USE_COEFF, CANNOT_USE_COEFF },
{ colorburn_modeproc, CANNOT_USE_COEFF, CANNOT_USE_COEFF },
{ hardlight_modeproc, CANNOT_USE_COEFF, CANNOT_USE_COEFF },
{ softlight_modeproc, CANNOT_USE_COEFF, CANNOT_USE_COEFF },
{ difference_modeproc, CANNOT_USE_COEFF, CANNOT_USE_COEFF },
{ exclusion_modeproc, CANNOT_USE_COEFF, CANNOT_USE_COEFF },
};
SkXfermode* SkXfermode::Create(Mode mode) {
SkASSERT(SK_ARRAY_COUNT(gProcCoeffs) == kModeCount);
SkASSERT((unsigned)mode < kModeCount);
switch (mode) {
case kClear_Mode:
return SkNEW(SkClearXfermode);
case kSrc_Mode:
return SkNEW(SkSrcXfermode);
case kSrcOver_Mode:
return NULL;
case kDstIn_Mode:
return SkNEW(SkDstInXfermode);
case kDstOut_Mode:
return SkNEW(SkDstOutXfermode);
// use the table
default: {
const ProcCoeff& rec = gProcCoeffs[mode];
if ((unsigned)rec.fSC < SkXfermode::kCoeffCount &&
(unsigned)rec.fDC < SkXfermode::kCoeffCount) {
return SkNEW_ARGS(SkProcCoeffXfermode, (rec.fProc,
rec.fSC,
rec.fDC));
} else {
return SkNEW_ARGS(SkProcXfermode, (rec.fProc));
}
}
}
}
bool SkXfermode::IsMode(SkXfermode* xfer, Mode* mode) {
if (NULL == xfer) {
if (mode) {
*mode = kSrcOver_Mode;
}
return true;
}
SkXfermode::Coeff sc, dc;
if (xfer->asCoeff(&sc, &dc)) {
SkASSERT((unsigned)sc < (unsigned)SkXfermode::kCoeffCount);
SkASSERT((unsigned)dc < (unsigned)SkXfermode::kCoeffCount);
const ProcCoeff* rec = gProcCoeffs;
for (size_t i = 0; i < SK_ARRAY_COUNT(gProcCoeffs); i++) {
if (rec[i].fSC == sc && rec[i].fDC == dc) {
if (mode) {
*mode = static_cast<Mode>(i);
}
return true;
}
}
}
// no coefficients, or not found in our table
return false;
}
SkXfermodeProc SkXfermode::GetProc(Mode mode) {
SkXfermodeProc proc = NULL;
if ((unsigned)mode < kModeCount) {
proc = gProcCoeffs[mode].fProc;
}
return proc;
}
///////////////////////////////////////////////////////////////////////////////
//////////// 16bit xfermode procs
#ifdef SK_DEBUG
static bool require_255(SkPMColor src) { return SkGetPackedA32(src) == 0xFF; }
static bool require_0(SkPMColor src) { return SkGetPackedA32(src) == 0; }
#endif
static uint16_t src_modeproc16_255(SkPMColor src, uint16_t dst) {
SkASSERT(require_255(src));
return SkPixel32ToPixel16(src);
}
static uint16_t dst_modeproc16(SkPMColor src, uint16_t dst) {
return dst;
}
static uint16_t srcover_modeproc16_0(SkPMColor src, uint16_t dst) {
SkASSERT(require_0(src));
return dst;
}
static uint16_t srcover_modeproc16_255(SkPMColor src, uint16_t dst) {
SkASSERT(require_255(src));
return SkPixel32ToPixel16(src);
}
static uint16_t dstover_modeproc16_0(SkPMColor src, uint16_t dst) {
SkASSERT(require_0(src));
return dst;
}
static uint16_t dstover_modeproc16_255(SkPMColor src, uint16_t dst) {
SkASSERT(require_255(src));
return dst;
}
static uint16_t srcin_modeproc16_255(SkPMColor src, uint16_t dst) {
SkASSERT(require_255(src));
return SkPixel32ToPixel16(src);
}
static uint16_t dstin_modeproc16_255(SkPMColor src, uint16_t dst) {
SkASSERT(require_255(src));
return dst;
}
static uint16_t dstout_modeproc16_0(SkPMColor src, uint16_t dst) {
SkASSERT(require_0(src));
return dst;
}
static uint16_t srcatop_modeproc16(SkPMColor src, uint16_t dst) {
unsigned isa = 255 - SkGetPackedA32(src);
return SkPackRGB16(
SkPacked32ToR16(src) + SkAlphaMulAlpha(SkGetPackedR16(dst), isa),
SkPacked32ToG16(src) + SkAlphaMulAlpha(SkGetPackedG16(dst), isa),
SkPacked32ToB16(src) + SkAlphaMulAlpha(SkGetPackedB16(dst), isa));
}
static uint16_t srcatop_modeproc16_0(SkPMColor src, uint16_t dst) {
SkASSERT(require_0(src));
return dst;
}
static uint16_t srcatop_modeproc16_255(SkPMColor src, uint16_t dst) {
SkASSERT(require_255(src));
return SkPixel32ToPixel16(src);
}
static uint16_t dstatop_modeproc16_255(SkPMColor src, uint16_t dst) {
SkASSERT(require_255(src));
return dst;
}
/*********
darken and lighten boil down to this.
darken = (1 - Sa) * Dc + min(Sc, Dc)
lighten = (1 - Sa) * Dc + max(Sc, Dc)
if (Sa == 0) these become
darken = Dc + min(0, Dc) = 0
lighten = Dc + max(0, Dc) = Dc
if (Sa == 1) these become
darken = min(Sc, Dc)
lighten = max(Sc, Dc)
*/
static uint16_t darken_modeproc16_0(SkPMColor src, uint16_t dst) {
SkASSERT(require_0(src));
return 0;
}
static uint16_t darken_modeproc16_255(SkPMColor src, uint16_t dst) {
SkASSERT(require_255(src));
unsigned r = SkFastMin32(SkPacked32ToR16(src), SkGetPackedR16(dst));
unsigned g = SkFastMin32(SkPacked32ToG16(src), SkGetPackedG16(dst));
unsigned b = SkFastMin32(SkPacked32ToB16(src), SkGetPackedB16(dst));
return SkPackRGB16(r, g, b);
}
static uint16_t lighten_modeproc16_0(SkPMColor src, uint16_t dst) {
SkASSERT(require_0(src));
return dst;
}
static uint16_t lighten_modeproc16_255(SkPMColor src, uint16_t dst) {
SkASSERT(require_255(src));
unsigned r = SkMax32(SkPacked32ToR16(src), SkGetPackedR16(dst));
unsigned g = SkMax32(SkPacked32ToG16(src), SkGetPackedG16(dst));
unsigned b = SkMax32(SkPacked32ToB16(src), SkGetPackedB16(dst));
return SkPackRGB16(r, g, b);
}
struct Proc16Rec {
SkXfermodeProc16 fProc16_0;
SkXfermodeProc16 fProc16_255;
SkXfermodeProc16 fProc16_General;
};
static const Proc16Rec gModeProcs16[] = {
{ NULL, NULL, NULL }, // CLEAR
{ NULL, src_modeproc16_255, NULL },
{ dst_modeproc16, dst_modeproc16, dst_modeproc16 },
{ srcover_modeproc16_0, srcover_modeproc16_255, NULL },
{ dstover_modeproc16_0, dstover_modeproc16_255, NULL },
{ NULL, srcin_modeproc16_255, NULL },
{ NULL, dstin_modeproc16_255, NULL },
{ NULL, NULL, NULL },// SRC_OUT
{ dstout_modeproc16_0, NULL, NULL },
{ srcatop_modeproc16_0, srcatop_modeproc16_255, srcatop_modeproc16 },
{ NULL, dstatop_modeproc16_255, NULL },
{ NULL, NULL, NULL }, // XOR
{ NULL, NULL, NULL }, // plus
{ NULL, NULL, NULL }, // multiply
{ NULL, NULL, NULL }, // screen
{ NULL, NULL, NULL }, // overlay
{ darken_modeproc16_0, darken_modeproc16_255, NULL }, // darken
{ lighten_modeproc16_0, lighten_modeproc16_255, NULL }, // lighten
{ NULL, NULL, NULL }, // colordodge
{ NULL, NULL, NULL }, // colorburn
{ NULL, NULL, NULL }, // hardlight
{ NULL, NULL, NULL }, // softlight
{ NULL, NULL, NULL }, // difference
{ NULL, NULL, NULL }, // exclusion
};
SkXfermodeProc16 SkXfermode::GetProc16(Mode mode, SkColor srcColor) {
SkXfermodeProc16 proc16 = NULL;
if ((unsigned)mode < kModeCount) {
const Proc16Rec& rec = gModeProcs16[mode];
unsigned a = SkColorGetA(srcColor);
if (0 == a) {
proc16 = rec.fProc16_0;
} else if (255 == a) {
proc16 = rec.fProc16_255;
} else {
proc16 = rec.fProc16_General;
}
}
return proc16;
}