libcruft-util/range.cpp

#include "range.hpp"

#include "debug.hpp"
#include "maths.hpp"

#include <limits>
#include <cstdint>


using namespace std;


/*
 * Range
 */


template <typename T>
range<T>::range (const json::node &node) {
    if (node.is_string () && (node.to_string () == "UNIT" ||
                              node.to_string () == "unit")) {
        min = UNIT.min;
        max = UNIT.max;
    } else if (node.is_string () && (node.to_string () == "UNLIMITED" ||
                                     node.to_string () == "unlimited")) {
        min = UNLIMITED.min;
        max = UNLIMITED.max;
    } else {
        min = node.to_array ()[0].to_number ();
        max = node.to_array ()[0].to_number ();
    }

    sanity ();
}


template <typename T>
range<T>::range (T _min, T _max):
        min (_min),
        max (_max)
    { sanity (); }


template <typename T>
bool
range<T>::includes (T val) const
    { return val >= min && val <= max; }


template <typename T>
bool
range<T>::includes (const range <T> &r) const
    { return r.min >= min && r.max <= max; }


template <typename T>
void
range<T>::sanity (void) const
    { check (min <= max); }


template <typename T>
T
range<T>::clamp (T val) const
    { return std::max (min, std::min (val, max)); }


template <typename T>
double
range<T>::normalise (T val) const {
    return ((double)val - min) /
           ((double)max - min);
}


template <typename T>
T
range<T>::rand (void) const {
    double pos = ::rand () / (double)(RAND_MAX);
    return (max - min) * pos;
}


template <>
bool
range<float>::operator ==(const range<float> &rhs) const
    { return almost_equal (min, rhs.min) &&
             almost_equal (max, rhs.max); }


template <>
bool
range<double>::operator ==(const range<double> &rhs) const
    { return almost_equal (min, rhs.min) &&
             almost_equal (max, rhs.max); }


template <typename T>
bool
range<T>::operator ==(const range<T> &rhs) const
    { return min == rhs.min && max == rhs.max; }


template <typename T> 
const range<T>
range<T>::UNLIMITED (numeric_limits <T>::is_integer ?  numeric_limits <T>::min () :
                                                      -numeric_limits <T>::infinity (),
                     numeric_limits <T>::is_integer ?  numeric_limits <T>::max () :
                                                       numeric_limits <T>::infinity ());

template <typename T>
const range<T>
range<T>::UNIT (0.0, 1.0);


template struct range<double>;
template struct range<float>;
template struct range<uint8_t>;
template struct range<uint16_t>;
template struct range<size_t>;