Reland "remove unused SkAvoidXfermode"

src/effects/SkAvoidXfermode.cpp

-/*
- * 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;
-    }
-    fTolerance = SkToU8(tolerance);
-    fOpColor = opColor;
-    fDistMul = (256 << 14) / (tolerance + 1);
-    fMode = mode;
-}
-
-SkFlattenable* SkAvoidXfermode::CreateProc(SkReadBuffer& buffer) {
-    const SkColor color = buffer.readColor();
-    const unsigned tolerance = buffer.readUInt();
-    const unsigned mode = buffer.readUInt();
-    return Create(color, tolerance, (Mode)mode);
-}
-
-void SkAvoidXfermode::flatten(SkWriteBuffer& buffer) const {
-    buffer.writeColor(fOpColor);
-    buffer.writeUInt(fTolerance);
-    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 (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 (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
-}
-
-#ifndef SK_IGNORE_TO_STRING
-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