math_funcs.h

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/*  math_funcs.h                                                         */
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#ifndef MATH_FUNCS_H
#define MATH_FUNCS_H

#include "typedefs.h"
#include "math_defs.h"

#ifndef NO_MATH_H
#include "math.h"
#endif

class Math {


    static uint32_t default_seed;
public:
    Math() {}; // useless to instance

    enum {
        RANDOM_MAX=2147483647L
    };

    static double sin(double p_x);
    static double cos(double p_x);
    static double tan(double p_x);
    static double sinh(double p_x);
    static double cosh(double p_x);
    static double tanh(double p_x);
    static double asin(double p_x);
    static double acos(double p_x);
    static double atan(double p_x);
    static double atan2(double p_y, double p_x);
    static double deg2rad(double p_y);
    static double rad2deg(double p_y);
    static double sqrt(double p_x);
    static double fmod(double p_x,double p_y);
    static double fposmod(double p_x,double p_y);
    static uint32_t rand_from_seed(uint32_t *seed);
    static double floor(double p_x);
    static double ceil(double p_x);
    static double ease(double p_x, double p_c);
    static int decimals(double p_step);
    static double stepify(double p_value,double p_step);
    static void seed(uint32_t x=0);
    static void randomize();
    static uint32_t larger_prime(uint32_t p_val);
    static double dectime(double p_value,double p_amount, double p_step);


    static inline double linear2db(double p_linear) {

        return Math::log( p_linear ) * 8.6858896380650365530225783783321;
    }

    static inline double db2linear(double p_db) {

        return Math::exp( p_db * 0.11512925464970228420089957273422 );
    }

    static bool is_nan(double p_val);
    static bool is_inf(double p_val);



    static uint32_t rand();
    static double randf();

    static double round(double p_val);

    static double random(double from, double to);


    static _FORCE_INLINE_ real_t abs(real_t g) {

#ifdef REAL_T_IS_DOUBLE

        return absd(g);
#else

        return absf(g);
#endif
    }

    static _FORCE_INLINE_ float absf(float g) {

        union {
            float f;
            uint32_t i;
        } u;

        u.f=g;
        u.i&=2147483647u;
        return u.f;
    }

    static _FORCE_INLINE_ double absd(double g) {

        union {
            double d;
            uint64_t i;
        } u;
        u.d=g;
        u.i&=(uint64_t)9223372036854775807ll;
        return u.d;
    }

    //this function should be as fast as possible and rounding mode should not matter
    static _FORCE_INLINE_ int fast_ftoi(float a) {

        static int b;

#if (defined(_WIN32_WINNT) && _WIN32_WINNT >= 0x0603) || WINAPI_FAMILY == WINAPI_FAMILY_PHONE_APP // windows 8 phone?
        b = (int)((a>0.0f) ? (a + 0.5f):(a -0.5f));

#elif defined(_MSC_VER) && _MSC_VER < 1800
        __asm fld a
        __asm fistp b
/*#elif defined( __GNUC__ ) && ( defined( __i386__ ) || defined( __x86_64__ ) )
        // use AT&T inline assembly style, document that
        // we use memory as output (=m) and input (m)
        __asm__ __volatile__ (
        "flds %1        \n\t"
        "fistpl %0      \n\t"
        : "=m" (b)
        : "m" (a));*/

#else
        b=lrintf(a); //assuming everything but msvc 2012 or earlier has lrint
#endif
        return  b;
    }


#if defined(__GNUC__)

    static _FORCE_INLINE_ int64_t dtoll(double p_double) { return (int64_t)p_double; } 
#else

    static _FORCE_INLINE_ int64_t dtoll(double p_double) { return (int64_t)p_double; } 
#endif

    static _FORCE_INLINE_ float lerp(float a, float b, float c) {

        return a+(b-a)*c;
    }

    static double pow(double x, double y);
    static double log(double x);
    static double exp(double x);

};


#define Math_PI 3.14159265358979323846
#define Math_SQRT12 0.7071067811865475244008443621048490

#endif // MATH_FUNCS_H