math_helpers.hpp

/******************************************************************************
 
  nomlib - C++11 cross-platform game engine
 
Copyright (c) 2013, 2014 Jeffrey Carpenter <i8degrees@gmail.com>
All rights reserved.
 
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******************************************************************************/
#ifndef NOMLIB_MATH_HELPERS_HPP
#define NOMLIB_MATH_HELPERS_HPP
 
#include <random>
#include <cmath>
 
#include "nomlib/config.hpp"
#include "nomlib/math/Point2.hpp"
#include "nomlib/math/Size2.hpp"
 
namespace nom {
 
const double PI = 4.0 * atan ( 1.0 );
 
namespace priv {
 
extern std::random_device rd;
extern std::default_random_engine rd_generator;
 
} // namespace priv

void init_rand(uint32 seed_seq);

template <typename T>
inline T uniform_int_rand(T start_range, T end_range)
{
  std::uniform_int_distribution<T> distribution(start_range, end_range);
 
  return distribution(priv::rd_generator);
}

template <typename T>
inline T uniform_real_rand(T start_range, T end_range)
{
  std::uniform_real_distribution<T> distribution(start_range, end_range);
 
  return distribution(priv::rd_generator);
}

const Point2d rotate_points ( float angle, float x, float y, float pivot_x, float pivot_y );

template <typename T>
inline T round_float(real32 number)
{
  real32 ret = number < 0.0f ? ceilf(number - 0.5f) : floorf(number + 0.5f);
  return NOM_SCAST(T, ret);
}

template <typename T>
inline T round_float_down(real32 number)
{
  real32 ret = floorf(number);
  return NOM_SCAST(T, ret);
}

template <typename T>
inline T round_float_up(real32 number)
{
  real32 ret = ceilf(number);
  return NOM_SCAST(T, ret);
}

template <typename T>
inline T round_double(real64 number)
{
  real64 ret = number < 0.0f ? ceil(number - 0.5f) : floor(number + 0.5f);
  return NOM_SCAST(T, ret);
}
 
// TODO(jeff): Rename to truncate_real32
template <typename T>
inline T truncate_float(real32 number)
{
  T ret = NOM_SCAST(T, number);
  return(ret);
}
 
// FIXME(jeff): We should provide two separate functions here, absolute_real32
// and absolute_real64. See also: man 3 fabs
inline real32 absolute_real32(real32 number)
{
  real32 result = fabsf(number);
 
  return result;
}
 
inline real64 absolute_real64(real64 number)
{
  real64 result = fabs(number);
 
  return result;
}
 
inline int absolute_int(int number)
{
  int result = std::abs(number);
 
  return result;
}

template <typename T>
inline T minimum(const T& a, const T& b)
{
  T result = (b < a) ? b : a;
  return result;
}

template <typename T>
inline T maximum(const T& a, const T& b)
{
  T result = (a < b) ? b : a;
  return result;
}

template <typename T>
inline T clamp_min(const T& a, const T& b)
{
  auto result = nom::minimum<T>(a, b);
  return result;
}

template <typename T>
inline T clamp_max(const T& a, const T& b)
{
  auto result = nom::maximum<T>(a, b);
  return result;
}
 
} // namespace nom
 
#endif // include guard defined