| /* |
| * Copyright 2006 The Android Open Source Project |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "SkAvoidXfermode.h" |
| #include "SkColorPriv.h" |
| #include "SkReadBuffer.h" |
| #include "SkWriteBuffer.h" |
| #include "SkString.h" |
| |
| SkAvoidXfermode::SkAvoidXfermode(SkColor opColor, U8CPU tolerance, Mode mode) { |
| if (tolerance > 255) { |
| tolerance = 255; |
| } |
| |
| fOpColor = opColor; |
| fDistMul = (256 << 14) / (tolerance + 1); |
| fMode = mode; |
| } |
| |
| SkAvoidXfermode::SkAvoidXfermode(SkReadBuffer& buffer) |
| : INHERITED(buffer) { |
| fOpColor = buffer.readColor(); |
| fDistMul = buffer.readUInt(); |
| fMode = (Mode)buffer.readUInt(); |
| } |
| |
| void SkAvoidXfermode::flatten(SkWriteBuffer& buffer) const { |
| this->INHERITED::flatten(buffer); |
| |
| buffer.writeColor(fOpColor); |
| buffer.writeUInt(fDistMul); |
| buffer.writeUInt(fMode); |
| } |
| |
| // returns 0..31 |
| static unsigned color_dist16(uint16_t c, unsigned r, unsigned g, unsigned b) { |
| SkASSERT(r <= SK_R16_MASK); |
| SkASSERT(g <= SK_G16_MASK); |
| SkASSERT(b <= SK_B16_MASK); |
| |
| unsigned dr = SkAbs32(SkGetPackedR16(c) - r); |
| unsigned dg = SkAbs32(SkGetPackedG16(c) - g) >> (SK_G16_BITS - SK_R16_BITS); |
| unsigned db = SkAbs32(SkGetPackedB16(c) - b); |
| |
| return SkMax32(dr, SkMax32(dg, db)); |
| } |
| |
| // returns 0..255 |
| static unsigned color_dist32(SkPMColor c, U8CPU r, U8CPU g, U8CPU b) { |
| SkASSERT(r <= 0xFF); |
| SkASSERT(g <= 0xFF); |
| SkASSERT(b <= 0xFF); |
| |
| unsigned dr = SkAbs32(SkGetPackedR32(c) - r); |
| unsigned dg = SkAbs32(SkGetPackedG32(c) - g); |
| unsigned db = SkAbs32(SkGetPackedB32(c) - b); |
| |
| return SkMax32(dr, SkMax32(dg, db)); |
| } |
| |
| static int scale_dist_14(int dist, uint32_t mul, uint32_t sub) { |
| int tmp = dist * mul - sub; |
| int result = (tmp + (1 << 13)) >> 14; |
| |
| return result; |
| } |
| |
| static inline unsigned Accurate255To256(unsigned x) { |
| return x + (x >> 7); |
| } |
| |
| void SkAvoidXfermode::xfer32(SkPMColor dst[], const SkPMColor src[], int count, |
| const SkAlpha aa[]) const { |
| unsigned opR = SkColorGetR(fOpColor); |
| unsigned opG = SkColorGetG(fOpColor); |
| unsigned opB = SkColorGetB(fOpColor); |
| uint32_t mul = fDistMul; |
| uint32_t sub = (fDistMul - (1 << 14)) << 8; |
| |
| int MAX, mask; |
| |
| if (kTargetColor_Mode == fMode) { |
| mask = -1; |
| MAX = 255; |
| } else { |
| mask = 0; |
| MAX = 0; |
| } |
| |
| for (int i = 0; i < count; i++) { |
| int d = color_dist32(dst[i], opR, opG, opB); |
| // now reverse d if we need to |
| d = MAX + (d ^ mask) - mask; |
| SkASSERT((unsigned)d <= 255); |
| d = Accurate255To256(d); |
| |
| d = scale_dist_14(d, mul, sub); |
| SkASSERT(d <= 256); |
| |
| if (d > 0) { |
| if (NULL != aa) { |
| d = SkAlphaMul(d, Accurate255To256(*aa++)); |
| if (0 == d) { |
| continue; |
| } |
| } |
| dst[i] = SkFourByteInterp256(src[i], dst[i], d); |
| } |
| } |
| } |
| |
| static inline U16CPU SkBlend3216(SkPMColor src, U16CPU dst, unsigned scale) { |
| SkASSERT(scale <= 32); |
| scale <<= 3; |
| |
| return SkPackRGB16( SkAlphaBlend(SkPacked32ToR16(src), SkGetPackedR16(dst), scale), |
| SkAlphaBlend(SkPacked32ToG16(src), SkGetPackedG16(dst), scale), |
| SkAlphaBlend(SkPacked32ToB16(src), SkGetPackedB16(dst), scale)); |
| } |
| |
| void SkAvoidXfermode::xfer16(uint16_t dst[], const SkPMColor src[], int count, |
| const SkAlpha aa[]) const { |
| unsigned opR = SkColorGetR(fOpColor) >> (8 - SK_R16_BITS); |
| unsigned opG = SkColorGetG(fOpColor) >> (8 - SK_G16_BITS); |
| unsigned opB = SkColorGetB(fOpColor) >> (8 - SK_R16_BITS); |
| uint32_t mul = fDistMul; |
| uint32_t sub = (fDistMul - (1 << 14)) << SK_R16_BITS; |
| |
| int MAX, mask; |
| |
| if (kTargetColor_Mode == fMode) { |
| mask = -1; |
| MAX = 31; |
| } else { |
| mask = 0; |
| MAX = 0; |
| } |
| |
| for (int i = 0; i < count; i++) { |
| int d = color_dist16(dst[i], opR, opG, opB); |
| // now reverse d if we need to |
| d = MAX + (d ^ mask) - mask; |
| SkASSERT((unsigned)d <= 31); |
| // convert from 0..31 to 0..32 |
| d += d >> 4; |
| d = scale_dist_14(d, mul, sub); |
| SkASSERT(d <= 32); |
| |
| if (d > 0) { |
| if (NULL != aa) { |
| d = SkAlphaMul(d, Accurate255To256(*aa++)); |
| if (0 == d) { |
| continue; |
| } |
| } |
| dst[i] = SkBlend3216(src[i], dst[i], d); |
| } |
| } |
| } |
| |
| void SkAvoidXfermode::xferA8(SkAlpha dst[], const SkPMColor src[], int count, |
| const SkAlpha aa[]) const { |
| // override in subclass |
| } |
| |
| #ifdef SK_DEVELOPER |
| void SkAvoidXfermode::toString(SkString* str) const { |
| str->append("SkAvoidXfermode: opColor: "); |
| str->appendHex(fOpColor); |
| str->appendf("distMul: %d ", fDistMul); |
| |
| static const char* gModeStrings[] = { "Avoid", "Target" }; |
| |
| str->appendf("mode: %s", gModeStrings[fMode]); |
| } |
| #endif |