#ifndef _DOLPHIN_MATH
#define _DOLPHIN_MATH

// this file is necessary to match mtx/quat.c

#define M_PI 3.141592653589793

#ifndef _MATH_INLINE
#define _MATH_INLINE static inline
#endif

extern int __float_nan[];
extern int __float_huge[];
extern int __double_huge[];

#define INFINITY (*(float *)__float_huge)
#define NAN (*(float *)__float_nan)
#define HUGE_VAL (*(double *)__double_huge)

#ifdef __MWERKS__
extern inline double sqrt(double x)
{
    if (x > 0.0) {
        double guess = __frsqrte(x); /* returns an approximation to    */
        guess = .5 * guess * (3.0 - guess * guess * x); /* now have 8 sig bits            */
        guess = .5 * guess * (3.0 - guess * guess * x); /* now have 16 sig bits            */
        guess = .5 * guess * (3.0 - guess * guess * x); /* now have 32 sig bits            */
        guess = .5 * guess * (3.0 - guess * guess * x); /* now have > 53 sig bits        */
        return x * guess;
    }
    else if (x == 0)
        return 0;
    else if (x)
        return NAN;

    return INFINITY;
}

extern inline float sqrtf(float x)
{
    const double _half = .5;
    const double _three = 3.0;
    volatile float y;
    if (x > 0.0f) {
        double guess = __frsqrte((double)x); // returns an approximation to
        guess = _half * guess * (_three - guess * guess * x); // now have 12 sig bits
        guess = _half * guess * (_three - guess * guess * x); // now have 24 sig bits
        guess = _half * guess * (_three - guess * guess * x); // now have 32 sig bits
        y = (float)(x * guess);
        return y;
    }
    return x;
}
#else
double sqrt(double x);
float sqrtf(float x);
#endif

double atan(double x);
double copysign(double x, double y);
double cos(double x);
double floor(double x);
double frexp(double x, int *exp);
double ldexp(double x, int exp);
double modf(double x, double *intpart);
double sin(double x);
double tan(double x);
double acos(double x);
double asin(double x);
double atan2(double y, double x);
double fmod(double x, double y);
double log(double x);
double pow(double x, double y);
float tanf(float x);

#ifdef __MWERKS__
extern inline double fabs(double x)
{
    return __fabs(x);
}
#else
double fabs(double x);
#endif

#endif