float components in xfermodes

src/core/SkXfer4f.cpp

-/*
- * Copyright 2016 Google Inc.
- *
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-
-#include "SkXfer4f.h"
-#include "SkPM4fPriv.h"
-#include "SkUtils.h"
-
-///////////////////////////////////////////////////////////////////////////////////////////////////
-
-void CLEAR_pm41p(uint32_t dst[], const SkPM4f& src, int count) {
-    sk_bzero(dst, count * sizeof(uint32_t));
-}
-
-void CLEAR_pm4np(uint32_t dst[], const SkPM4f src[], int count) {
-    sk_bzero(dst, count * sizeof(uint32_t));
-}
-
-//////////
-
-template <bool isSRGB> void SRC_pm41p(uint32_t dst[], const SkPM4f& src, int count) {
-    uint32_t res;
-    if (isSRGB) {
-        res = Sk4f_toS32(Sk4f::Load(src.fVec));
-    } else {
-        res = Sk4f_toL32(Sk4f::Load(src.fVec));
-    }
-    sk_memset32(dst, res, count);
-}
-
-template <bool isSRGB> void SRC_pm4np(uint32_t dst[], const SkPM4f src[], int count) {
-    if (isSRGB) {
-        SkPM4f_s32_src_mode(dst, src, count);
-    } else {
-        SkPM4f_l32_src_mode(dst, src, count);
-    }
-}
-
-//////////
-
-void DST_pm41p(uint32_t dst[], const SkPM4f& src, int count) {}
-void DST_pm4np(uint32_t dst[], const SkPM4f src[], int count) {}
-
-//////////
-
-template <bool isSRGB> void SRCOVER_pm41p(uint32_t dst[], const SkPM4f& src, int count) {
-    SkASSERT(src.isUnit());
-    Sk4f s4 = Sk4f::Load(src.fVec);
-    Sk4f scale(1 - s4.kth<SkPM4f::A>());
-
-    if (!isSRGB) {
-        s4 = s4 * Sk4f(255);
-    }
-
-    for (int i = 0; i < count; ++i) {
-        if (isSRGB) {
-            Sk4f d4 = Sk4f_fromS32(dst[i]);
-            dst[i] = Sk4f_toS32(s4 + d4 * scale);
-        } else {
-            Sk4f d4 = to_4f(dst[i]);
-            dst[i] = to_4b(s4 + d4 * scale + Sk4f(0.5f));
-        }
-    }
-}
-
-template <bool isSRGB> void SRCOVER_pm4np(uint32_t dst[], const SkPM4f src[], int count) {
-    if (isSRGB) {
-        SkPM4f_s32_srcover_mode(dst, src, count);
-    } else {
-        SkPM4f_l32_srcover_mode(dst, src, count);
-    }
-}
-
-///////////////////////////////////////////////////////////////////////////////////////////////////
-
-struct Pair {
-    SkPM4fXfer1Proc fProc1;
-    SkPM4fXferNProc fProcN;
-};
-
-const Pair gClearPairs[] = {
-    { CLEAR_pm41p, CLEAR_pm4np },
-    { CLEAR_pm41p, CLEAR_pm4np },
-    { CLEAR_pm41p, CLEAR_pm4np },
-    { CLEAR_pm41p, CLEAR_pm4np },
-};
-
-const Pair gSrcPairs[] = {
-    { SRC_pm41p<false>, SRC_pm4np<false> }, // linear [alpha  ignored]
-    { SRC_pm41p<false>, SRC_pm4np<false> }, // linear [opaque ignored]
-    { SRC_pm41p<true>,  SRC_pm4np<true>  }, // srgb   [alpha  ignored]
-    { SRC_pm41p<true>,  SRC_pm4np<true>  }, // srgb   [opaque ignored]
-};
-
-const Pair gDstPairs[] = {
-    { DST_pm41p, DST_pm4np },
-    { DST_pm41p, DST_pm4np },
-    { DST_pm41p, DST_pm4np },
-    { DST_pm41p, DST_pm4np },
-};
-
-const Pair gSrcOverPairs[] = {
-    { SRCOVER_pm41p<false>,   SRCOVER_pm4np<false>  },  // linear   alpha
-    { SRC_pm41p<false>,       SRC_pm4np<false>      },  // linear   opaque
-    { SRCOVER_pm41p<true>,    SRCOVER_pm4np<true>   },  // srgb     alpha
-    { SRC_pm41p<true>,        SRC_pm4np<true>       },  // srgb     opaque
-};
-
-static const Pair* find_pair(SkXfermode::Mode mode, uint32_t flags) {
-    SkASSERT(0 == (flags & ~3));
-    const Pair* pairs = nullptr;
-
-    switch (mode) {
-        case SkXfermode::kClear_Mode:   pairs = gClearPairs;
-        case SkXfermode::kSrc_Mode:     pairs = gSrcPairs; break;
-        case SkXfermode::kDst_Mode:     pairs = gDstPairs;
-        case SkXfermode::kSrcOver_Mode: pairs = gSrcOverPairs; break;
-        default: return nullptr;
-    }
-    return &pairs[flags & 3];
-}
-
-SkPM4fXfer1Proc SkPM4fXfer1ProcFactory(SkXfermode::Mode mode, uint32_t flags) {
-    const Pair* pair = find_pair(mode, flags);
-    return pair ? pair->fProc1 : nullptr;
-}
-
-SkPM4fXferNProc SkPM4fXferNProcFactory(SkXfermode::Mode mode, uint32_t flags) {
-    const Pair* pair = find_pair(mode, flags);
-    return pair ? pair->fProcN : nullptr;
-}