Add GrColor4f type, store that in GrPaint. Linearize based on global flag.

include/gpu/GrColor.h

 
 /*
  * Copyright 2010 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 
@@ skipping 151 matching lines @@
     SkColor colorUPM = SkUnPreMultiply::PMColorToColor(colorPM);
 
     r = SkColorGetR(colorUPM);
     g = SkColorGetG(colorUPM);
     b = SkColorGetB(colorUPM);
     a = SkColorGetA(colorUPM);
 
     return GrColorPackRGBA(r, g, b, a);
 }
 
+
+/**
+* Similarly, GrColor4f is 4 floats for R, G, B, A, in that order. And like GrColor, whether
+* the color is premultiplied or not depends on the context.
+*/
+struct GrColor4f {
+    float fRGBA[4];
+
+    GrColor4f() {}
+    GrColor4f(float r, float g, float b, float a) {
+        fRGBA[0] = r;
+        fRGBA[1] = g;
+        fRGBA[2] = b;
+        fRGBA[3] = a;
+    }
+
+    static GrColor4f FromGrColor(GrColor color) {
+        GrColor4f result;
+        GrColorToRGBAFloat(color, result.fRGBA);
+        return result;
+    }
+
+    static GrColor4f FromSkColor4f(const SkColor4f& color) {
+        return GrColor4f(color.fR, color.fG, color.fB, color.fA);
+    }
+
+    GrColor toGrColor() const {
+        return GrColorPackRGBA(
+            SkTPin<unsigned>(static_cast<unsigned>(fRGBA[0] * 255.0f + 0.5f), 0, 255),
+            SkTPin<unsigned>(static_cast<unsigned>(fRGBA[1] * 255.0f + 0.5f), 0, 255),
+            SkTPin<unsigned>(static_cast<unsigned>(fRGBA[2] * 255.0f + 0.5f), 0, 255),
+            SkTPin<unsigned>(static_cast<unsigned>(fRGBA[3] * 255.0f + 0.5f), 0, 255));
+    }
+
+    SkColor4f toSkColor4f() const {
+        return SkColor4f{ fRGBA[3], fRGBA[0], fRGBA[1], fRGBA[2] };
+    }
+
+    GrColor4f opaque() const {
+        return GrColor4f(fRGBA[0], fRGBA[1], fRGBA[2], 1.0f);
+    }
+
+    GrColor4f premul() const {
+        float a = fRGBA[3];
+        return GrColor4f(fRGBA[0] * a, fRGBA[1] * a, fRGBA[2] * a, a);
+    }
+};
+
 /**
  * Flags used for bitfields of color components. They are defined so that the bit order reflects the
  * GrColor shift order.
  */
 enum GrColorComponentFlags {
     kR_GrColorComponentFlag = 1 << (GrColor_SHIFT_R / 8),
     kG_GrColorComponentFlag = 1 << (GrColor_SHIFT_G / 8),
     kB_GrColorComponentFlag = 1 << (GrColor_SHIFT_B / 8),
     kA_GrColorComponentFlag = 1 << (GrColor_SHIFT_A / 8),
 
@@ skipping 59 matching lines @@
     GR_STATIC_ASSERT(10  == kLATC_GrPixelConfig);
     GR_STATIC_ASSERT(11  == kR11_EAC_GrPixelConfig);
     GR_STATIC_ASSERT(12 == kASTC_12x12_GrPixelConfig);
     GR_STATIC_ASSERT(13 == kRGBA_float_GrPixelConfig);
     GR_STATIC_ASSERT(14 == kAlpha_half_GrPixelConfig);
     GR_STATIC_ASSERT(15 == kRGBA_half_GrPixelConfig);
     GR_STATIC_ASSERT(SK_ARRAY_COUNT(kFlags) == kGrPixelConfigCnt);
 }
 
 #endif