add kRGBA_F16_SkColorType

include/core/SkColor.h

 /*
  * 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.
  */
 
 #ifndef SkColor_DEFINED
 #define SkColor_DEFINED
 
@@ skipping 162 matching lines @@
         B = SK_B32_SHIFT/8,
     };
     float fVec[4];
 
     float a() const { return fVec[A]; }
 
     SkColor4f unpremul() const;
 
     static SkPM4f FromPMColor(SkPMColor);
 
+    // half-float routines
+    void toF16(uint16_t[4]) const;
+    uint64_t toF16() const; // 4 float16 values packed into uint64_t
+    static SkPM4f FromF16(const uint16_t[4]);
+
 #ifdef SK_DEBUG
     void assertIsUnit() const;
 #else
     void assertIsUnit() const {}
 #endif
 };
 
 /*
  *  The float values are 0...1 unpremultiplied
  */
@@ skipping 17 matching lines @@
     static SkColor4f FromColor(SkColor);
 
     SkColor4f pin() const {
         return Pin(fA, fR, fG, fB);
     }
 
     SkPM4f premul() const;
 };
 
 #endif