Revert of experiment: float color components (patchset #6 id:100001 of https://codereview.chromium.org/1617813002/ )

Reason for revert:
broke some colormatrix tests

Original issue's description:
> experiment: float color components
>
> BUG=skia:
> GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1617813002
>
> Committed: https://skia.googlesource.com/skia/+/353c148d8e8c9031daca34c6f9d6bcc6f08706c7

TBR=fmalita@chromium.org,mtklein@google.com,herb@google.com
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Review URL: https://codereview.chromium.org/1623453002

5 files changed, 1 insertions, 59 deletions

diff --git a/src/core/SkColor.cpp b/src/core/SkColor.cpp
index c9f4a1433d..a21f019239 100644
--- a/src/core/SkColor.cpp
+++ b/src/core/SkColor.cpp
@@ -100,37 +100,3 @@ SkColor SkHSVToColor(U8CPU a, const SkScalar hsv[3]) {
     }
     return SkColorSetARGB(a, r, g, b);
 }
-
-///////////////////////////////////////////////////////////////////////////////////////////////////
-#include "SkNx.h"
-
-SkColor4f SkColor4f::Pin(float a, float r, float g, float b) {
-    SkColor4f c4;
-    Sk4f::Min(Sk4f::Max(Sk4f(a, r, g, b), Sk4f(0)), Sk4f(1)).store(c4.vec());
-    return c4;
-}
-
-SkColor4f SkColor4f::FromColor(SkColor c) {
-    Sk4f value = SkNx_shuffle<3,2,1,0>(SkNx_cast<float>(Sk4b::Load((const uint8_t*)&c)));
-    SkColor4f c4;
-    (value * Sk4f(1.0f / 255)).store(c4.vec());
-    return c4;
-}
-
-SkPM4f SkColor4f::premul() const {
-    auto src = Sk4f::Load(this->pin().vec());
-    float srcAlpha = src.kth<0>();  // need the pinned version of our alpha
-    src = src * Sk4f(1, srcAlpha, srcAlpha, srcAlpha);
-
-#ifdef SK_PMCOLOR_IS_BGRA
-    // ARGB -> BGRA
-    Sk4f dst = SkNx_shuffle<3,2,1,0>(src);
-#else
-    // ARGB -> RGBA
-    Sk4f dst = SkNx_shuffle<1,2,3,0>(src);
-#endif
-
-    SkPM4f pm4;
-    dst.store(pm4.fVec);
-    return pm4;
-}
diff --git a/src/core/SkColorFilter.cpp b/src/core/SkColorFilter.cpp
index 4bfacfe544..747e5ee107 100644
--- a/src/core/SkColorFilter.cpp
+++ b/src/core/SkColorFilter.cpp
@@ -35,10 +35,6 @@ SkColor SkColorFilter::filterColor(SkColor c) const {
     return SkUnPreMultiply::PMColorToColor(dst);
 }
 
-void SkColorFilter::filterSpan4f(const SkPM4f[], int count, SkPM4f[]) const {
-    SkASSERT(false && "filterSpan4f called but not implemented");
-}
-
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 
 /*
diff --git a/src/core/SkColorShader.h b/src/core/SkColorShader.h
index 1c07a3c124..25a1d6c8d0 100644
--- a/src/core/SkColorShader.h
+++ b/src/core/SkColorShader.h
@@ -36,10 +36,8 @@ public:
         uint32_t getFlags() const override;
         void shadeSpan(int x, int y, SkPMColor span[], int count) override;
         void shadeSpanAlpha(int x, int y, uint8_t alpha[], int count) override;
-        void shadeSpan4f(int x, int y, SkPM4f[], int count) override;
 
     private:
-        SkPM4f      fPM4f;
         SkPMColor   fPMColor;
         uint32_t    fFlags;
 
diff --git a/src/core/SkMathPriv.h b/src/core/SkMathPriv.h
index 6cca44e958..b9184a0726 100644
--- a/src/core/SkMathPriv.h
+++ b/src/core/SkMathPriv.h
@@ -78,8 +78,4 @@ static inline unsigned SkDiv255Round(unsigned prod) {
     return (prod + (prod >> 8)) >> 8;
 }
 
-static inline float SkPinToUnitFloat(float x) {
-    return SkTMin(SkTMax(x, 0.0f), 1.0f);
-}
-
 #endif
diff --git a/src/core/SkShader.cpp b/src/core/SkShader.cpp
index 856b659213..bd3876a69b 100644
--- a/src/core/SkShader.cpp
+++ b/src/core/SkShader.cpp
@@ -117,10 +117,6 @@ SkShader::Context::ShadeProc SkShader::Context::asAShadeProc(void** ctx) {
     return nullptr;
 }
 
-void SkShader::Context::shadeSpan4f(int x, int y, SkPM4f[], int count) {
-    SkASSERT(false && "shadeSpan4f called but not implemented");
-}
-
 #include "SkColorPriv.h"
 
 #define kTempColorQuadCount 6   // balance between speed (larger) and saving stack-space
@@ -283,11 +279,7 @@ SkColorShader::ColorShaderContext::ColorShaderContext(const SkColorShader& shade
     }
     fPMColor = SkPackARGB32(a, r, g, b);
 
-    SkColor4f c4 = SkColor4f::FromColor(shader.fColor);
-    c4.fA *= rec.fPaint->getAlpha() / 255.0f;
-    fPM4f = c4.premul();
-
-    fFlags = kConstInY32_Flag | kSupports4f_Flag;
+    fFlags = kConstInY32_Flag;
     if (255 == a) {
         fFlags |= kOpaqueAlpha_Flag;
     }
@@ -301,12 +293,6 @@ void SkColorShader::ColorShaderContext::shadeSpanAlpha(int x, int y, uint8_t alp
     memset(alpha, SkGetPackedA32(fPMColor), count);
 }
 
-void SkColorShader::ColorShaderContext::shadeSpan4f(int x, int y, SkPM4f span[], int count) {
-    for (int i = 0; i < count; ++i) {
-        span[i] = fPM4f;
-    }
-}
-
 SkShader::GradientType SkColorShader::asAGradient(GradientInfo* info) const {
     if (info) {
         if (info->fColors && info->fColorCount >= 1) {