Limits.hpp

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/**
 * @file Limits.hpp
 *
 * Limiting / constrain helper functions
 */

#pragma once

#include <float.h>
#include <math.h>
#include <stdint.h>

#ifndef MATH_PI
#define MATH_PI     3.141592653589793238462643383280
#endif

namespace math
{

template<typename _Tp>
constexpr _Tp min(_Tp a, _Tp b)
{
    return (a < b) ? a : b;
}

template<typename _Tp>
constexpr _Tp max(_Tp a, _Tp b)
{
    return (a > b) ? a : b;
}

template<typename _Tp>
constexpr _Tp constrain(_Tp val, _Tp min_val, _Tp max_val)
{
    return (val < min_val) ? min_val : ((val > max_val) ? max_val : val);
}

/** Constrain float values to valid values for int16_t.
 * Invalid values are just clipped to be in the range for int16_t. */
constexpr int16_t constrainFloatToInt16(float value)
{
    return (int16_t)math::constrain(value, (float)INT16_MIN, (float)INT16_MAX);
}

template<typename _Tp>
constexpr bool isInRange(_Tp val, _Tp min_val, _Tp max_val)
{
    return (min_val <= val) && (val <= max_val);
}

template<typename T>
constexpr T radians(T degrees)
{
    return degrees * (static_cast<T>(MATH_PI) / static_cast<T>(180));
}

template<typename T>
constexpr T degrees(T radians)
{
    return radians * (static_cast<T>(180) / static_cast<T>(MATH_PI));
}

/** Safe way to check if float is zero */
inline bool isZero(float val)
{
    return fabsf(val - 0.0f) < FLT_EPSILON;
}

/** Safe way to check if double is zero */
inline bool isZero(double val)
{
    return fabs(val - 0.0) < DBL_EPSILON;
}

}