basic.h

Go to the documentation of this file.

 
#pragma once
 
#include <random>
 
namespace core
{
constexpr float Abs(float v)
{
    return v < 0.0f ? -v : v;
}
 
constexpr  bool Equal(float a, float b, float epsilon = 0.0000001f)
{
    return Abs(a - b) < epsilon;
}
 
constexpr float Lerp(float start, float end, float t)
{
    return start + (end - start) * t;
}
 
template<typename T>
constexpr float Clamp(T value, T lower, T upper)
{
    return value < lower ? lower : (value > upper ? upper : value);
}
 
template<typename T>
typename std::enable_if<std::is_integral<T>::value, T>::type RandomRange(T start, T end)
{
    static std::random_device rd;  //Will be used to obtain a seed for the random number engine
    static std::mt19937 gen(rd()); //Standard mersenne_twister_engine seeded with rd()
    std::uniform_int_distribution<T> dis(start, end);
    return dis(gen);
}
 
template<typename T>
typename std::enable_if<std::is_floating_point<T>::value, T>::type RandomRange(T start, T end)
{
    static std::random_device rd;  //Will be used to obtain a seed for the random number engine
    static std::mt19937 gen(rd()); //Standard mersenne_twister_engine seeded with rd()
    std::uniform_real_distribution<T> dis(start, end);
    return dis(gen);
}
template<typename T>
T constexpr SqrtNewtonRaphson(T x, T curr, T prev)
{
    return curr == prev
           ? curr
           : SqrtNewtonRaphson<T>(x, (curr + x / curr) * 0.5, curr);
}
 
 
template<typename T>
T constexpr Sqrt(T x)
{
    return x >= 0 && x < std::numeric_limits<T>::infinity()
           ? SqrtNewtonRaphson<T>(x, x, 0)
           : std::numeric_limits<T>::quiet_NaN();
}
}