C++程序  |  27行  |  645 B

/*
 * Copyright 2014 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#ifndef SkHalf_DEFINED
#define SkHalf_DEFINED

#include "SkTypes.h"

// 16-bit floating point value
// format is 1 bit sign, 5 bits exponent, 10 bits mantissa
// only used for storage
typedef uint16_t SkHalf;

#define SK_HalfMin      0x0400   // 2^-24  (minimum positive normal value)
#define SK_HalfMax      0x7bff   // 65504
#define SK_HalfEpsilon  0x1400   // 2^-10

// convert between half and single precision floating point
float SkHalfToFloat(SkHalf h);
SkHalf SkFloatToHalf(float f);

#endif