/*
contributors: Patricio Gonzalez Vivo
description: some useful math constants
license:
    - Copyright (c) 2021 Patricio Gonzalez Vivo under Prosperity License - https://prosperitylicense.com/versions/3.0.0
    - Copyright (c) 2021 Patricio Gonzalez Vivo under Patron License - https://lygia.xyz/license
*/
#ifndef EIGHTH_PI
#define EIGHTH_PI 0.39269908169
#endif
#ifndef QTR_PI
#define QTR_PI 0.78539816339
#endif
#ifndef HALF_PI
#define HALF_PI 1.5707963267948966192313216916398
#endif
#ifndef PI
#define PI 3.1415926535897932384626433832795
#endif
#ifndef TWO_PI
#define TWO_PI 6.2831853071795864769252867665590
#endif
#ifndef TAU
#define TAU 6.2831853071795864769252867665590
#endif
#ifndef INV_PI
#define INV_PI 0.31830988618379067153776752674503
#endif
#ifndef INV_SQRT_TAU
#define INV_SQRT_TAU 0.39894228040143267793994605993439  // 1.0/SQRT_TAU
#endif
#ifndef SQRT_HALF_PI
#define SQRT_HALF_PI 1.25331413732
#endif
#ifndef PHI
#define PHI 1.618033988749894848204586834
#endif
#ifndef EPSILON
#define EPSILON 0.0000001
#endif
#ifndef GOLDEN_RATIO
#define GOLDEN_RATIO 1.6180339887
#endif
#ifndef GOLDEN_RATIO_CONJUGATE 
#define GOLDEN_RATIO_CONJUGATE 0.61803398875
#endif
#ifndef GOLDEN_ANGLE // (3.-sqrt(5.0))*PI radians
#define GOLDEN_ANGLE 2.39996323
#endif
#ifndef DEG2RAD
#define DEG2RAD (PI / 180.0)
#endif
#ifndef RAD2DEG
#define RAD2DEG (180.0 / PI)
#endif