Correct sRGB <-> linear everywhere.

src/core/SkColor.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 "SkColor.h"
 #include "SkColorPriv.h"
 #include "SkFixed.h"
@@ skipping 88 matching lines @@
         default: r = v; g = p; b = q; break;
     }
     return SkColorSetARGB(a, r, g, b);
 }
 
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 #include "SkPM4fPriv.h"
 #include "SkHalf.h"
 
 SkPM4f SkPM4f::FromPMColor(SkPMColor c) {
-    Sk4f value = to_4f_rgba(c);
-    SkPM4f c4;
-    (value * Sk4f(1.0f / 255)).store(&c4);
-    return c4;
+    return From4f(swizzle_rb_if_bgra(Sk4f_fromL32(c)));
 }
 
 SkColor4f SkPM4f::unpremul() const {
     float alpha = fVec[A];
     if (0 == alpha) {
         return { 0, 0, 0, 0 };
     } else {
         float invAlpha = 1 / alpha;
         return { fVec[R] * invAlpha, fVec[G] * invAlpha, fVec[B] * invAlpha, alpha };
     }
@@ skipping 22 matching lines @@
 
 #ifdef SK_DEBUG
 void SkPM4f::assertIsUnit() const {
     auto c4 = Sk4f::Load(fVec);
     SkASSERT((c4 >= Sk4f(0)).allTrue() && (c4 <= Sk4f(1)).allTrue());
 }
 #endif
 
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 
-SkColor4f SkColor4f::FromColor(SkColor c) {
-    Sk4f value = SkNx_shuffle<2,1,0,3>(SkNx_cast<float>(Sk4b::Load(&c)));
-    SkColor4f c4;
-    (value * Sk4f(1.0f / 255)).store(&c4);
-    c4.fR = srgb_to_linear(c4.fR);
-    c4.fG = srgb_to_linear(c4.fG);
-    c4.fB = srgb_to_linear(c4.fB);
-    return c4;
+SkColor4f SkColor4f::FromColor(SkColor bgra) {
+    SkColor4f rgba;
+    swizzle_rb(Sk4f_fromS32(bgra)).store(rgba.vec());
+    return rgba;
 }
 
 SkColor SkColor4f::toSkColor() const {
-    SkColor result;
-    Sk4f value = Sk4f(linear_to_srgb(fB), linear_to_srgb(fG), linear_to_srgb(fR), fA);
-    SkNx_cast<uint8_t>(value * Sk4f(255) + Sk4f(0.5f)).store(&result);
-    return result;
+    return Sk4f_toS32(swizzle_rb(Sk4f::Load(this->vec())));
 }
 
 SkColor4f SkColor4f::Pin(float r, float g, float b, float a) {
     SkColor4f c4;
     Sk4f::Min(Sk4f::Max(Sk4f(r, g, b, a), Sk4f(0)), Sk4f(1)).store(c4.vec());
     return c4;
 }
 
 SkPM4f SkColor4f::premul() const {
     auto src = Sk4f::Load(this->pin().vec());
     float srcAlpha = src[3];  // need the pinned version of our alpha
     src = src * Sk4f(srcAlpha, srcAlpha, srcAlpha, 1);
 
     return SkPM4f::From4f(src);
 }