text: 
  /*
   * 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 SkFloatingPoint_DEFINED
  #define SkFloatingPoint_DEFINED
  
  #include "SkTypes.h"
  
  #include <math.h>
  #include <float.h>
  #include "SkFloatBits.h"
  
  // C++98 cmath std::pow seems to be the earliest portable way to get float pow.
  // However, on Linux including cmath undefines isfinite.
  // http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14608
  static inline float sk_float_pow(float base, float exp) {
      return powf(base, exp);
  }
  
  static inline float sk_float_copysign(float x, float y) {
      int32_t xbits = SkFloat2Bits(x);
      int32_t ybits = SkFloat2Bits(y);
      return SkBits2Float((xbits & 0x7FFFFFFF) | (ybits & 0x80000000));
  }
  
  #ifdef SK_BUILD_FOR_WINCE
      #define sk_float_sqrt(x)        (float)::sqrt(x)
      #define sk_float_sin(x)         (float)::sin(x)
      #define sk_float_cos(x)         (float)::cos(x)
      #define sk_float_tan(x)         (float)::tan(x)
      #define sk_float_acos(x)        (float)::acos(x)
      #define sk_float_asin(x)        (float)::asin(x)
      #define sk_float_atan2(y,x)     (float)::atan2(y,x)
      #define sk_float_abs(x)         (float)::fabs(x)
      #define sk_float_mod(x,y)       (float)::fmod(x,y)
      #define sk_float_exp(x)         (float)::exp(x)
      #define sk_float_log(x)         (float)::log(x)
      #define sk_float_floor(x)       (float)::floor(x)
      #define sk_float_ceil(x)        (float)::ceil(x)
  #else
      #define sk_float_sqrt(x)        sqrtf(x)
      #define sk_float_sin(x)         sinf(x)
      #define sk_float_cos(x)         cosf(x)
      #define sk_float_tan(x)         tanf(x)
      #define sk_float_floor(x)       floorf(x)
      #define sk_float_ceil(x)        ceilf(x)
  #ifdef SK_BUILD_FOR_MAC
      #define sk_float_acos(x)        static_cast<float>(acos(x))
      #define sk_float_asin(x)        static_cast<float>(asin(x))
  #else
      #define sk_float_acos(x)        acosf(x)
      #define sk_float_asin(x)        asinf(x)
  #endif
      #define sk_float_atan2(y,x)     atan2f(y,x)
      #define sk_float_abs(x)         fabsf(x)
      #define sk_float_mod(x,y)       fmodf(x,y)
      #define sk_float_exp(x)         expf(x)
      #define sk_float_log(x)         logf(x)
  #endif
  
  #ifdef SK_BUILD_FOR_WIN
      #define sk_float_isfinite(x)    _finite(x)
      #define sk_float_isnan(x)       _isnan(x)
      static inline int sk_float_isinf(float x) {
          int32_t bits = SkFloat2Bits(x);
          return (bits << 1) == (0xFF << 24);
      }
  #else
      #define sk_float_isfinite(x)    isfinite(x)
      #define sk_float_isnan(x)       isnan(x)
      #define sk_float_isinf(x)       isinf(x)
  #endif
  
  #define sk_double_isnan(a)          sk_float_isnan(a)
  
  #ifdef SK_USE_FLOATBITS
      #define sk_float_floor2int(x)   SkFloatToIntFloor(x)
      #define sk_float_round2int(x)   SkFloatToIntRound(x)
      #define sk_float_ceil2int(x)    SkFloatToIntCeil(x)
  #else
      #define sk_float_floor2int(x)   (int)sk_float_floor(x)
      #define sk_float_round2int(x)   (int)sk_float_floor((x) + 0.5f)
      #define sk_float_ceil2int(x)    (int)sk_float_ceil(x)
  #endif
  
  extern const uint32_t gIEEENotANumber;
  extern const uint32_t gIEEEInfinity;
  extern const uint32_t gIEEENegativeInfinity;
  
  #define SK_FloatNaN                 (*SkTCast<const float*>(&gIEEENotANumber))
  #define SK_FloatInfinity            (*SkTCast<const float*>(&gIEEEInfinity))
  #define SK_FloatNegativeInfinity    (*SkTCast<const float*>(&gIEEENegativeInfinity))
  #endif
  