glm/test/gtx/gtx-ulp.cpp
2011-05-04 00:54:35 +01:00

105 lines
2.7 KiB
C++

///////////////////////////////////////////////////////////////////////////////////////////////////
// OpenGL Mathematics Copyright (c) 2005 - 2011 G-Truc Creation (www.g-truc.net)
///////////////////////////////////////////////////////////////////////////////////////////////////
// Created : 2011-04-26
// Updated : 2011-04-26
// Licence : This source is under MIT licence
// File : test/gtx/ulp.cpp
///////////////////////////////////////////////////////////////////////////////////////////////////
#include <glm/glm.hpp>
#include <glm/gtx/ulp.hpp>
#include <iostream>
#include <limits>
namespace
{
template <typename T>
T next(T const & x);
#if(GLM_COMPILER & GLM_COMPILER_VC)
# include <cfloat>
GLM_FUNC_QUALIFIER float next(float const & x)
{
return _nextafterf(x, std::numeric_limits<float>::max());
}
GLM_FUNC_QUALIFIER double next(double const & x)
{
return _nextafter(x, std::numeric_limits<double>::max());
}
#else
# include <cmath>
GLM_FUNC_QUALIFIER float next(float const & x)
{
return nextafterf(x, std::numeric_limits<float>::max());
}
GLM_FUNC_QUALIFIER double next(double const & x)
{
return nextafter(x, std::numeric_limits<double>::max());
}
#endif
template <typename T>
GLM_FUNC_QUALIFIER T next(T const & x, std::size_t const & Steps)
{
T temp = x;
for(std::size_t i = 0; i < Steps; ++i)
temp = next(temp);
return temp;
}
template <typename T>
GLM_FUNC_QUALIFIER std::size_t ulp_distance(T const & x, T const & y)
{
std::size_t ulp = 0;
T temp = x;
while(temp != y)
{
++ulp;
temp = next(temp);
}
return ulp;
}
}//namespace
int test_ulp_float()
{
std::cout.precision(std::numeric_limits<double>::digits10 + 1);
float W = 1.0f;
float X = next(W);
bool TestX = W != X;
std::cout << " 1.0f, Next: " << ulp_distance(W, X)<< std::endl;
std::cout << " 1.0f, Nextt(1000): " << next(W, 1000)<< std::endl;
//std::cout << " 0.01, 0.011: " << ulp_distance(0.00000000001f, 0.000000000011f) << std::endl;
//std::cout << " 0.01, 0.011: " << ulp_distance(0.00000000001, 0.000000000011) << std::endl;
double Y = 1.0;
double Z = next(Y);
bool TestZ = Y != Z;
std::cout << Z << " 0.01, 0.011" << std::endl;
std::cout << " 1.0, Next(1000000): " << next(Y, 1000000)<< std::endl;
std::size_t A = glm::ulp(0.01, 0.02);
std::size_t B = glm::ulp(glm::vec2(0.01), glm::vec2(0.02));
std::size_t C = glm::ulp(glm::vec3(0.01), glm::vec3(0.02));
std::size_t D = glm::ulp(glm::vec4(0.01), glm::vec4(0.02));
std::cout << "glm::ulp test: " << A << std::endl;
std::cout << "glm::ulp test: " << B << std::endl;
std::cout << "glm::ulp test: " << C << std::endl;
std::cout << "glm::ulp test: " << D << std::endl;
return 0;
}
int main()
{
std::cout << "Test 76" << std::endl;
test_ulp_float();
}