Properly use typed math constants instead of impl. specific hacks

PI is not in the stdlib, neither is 1/pi, pi*2 and so on. Instead
of relying on implementations providing these, use properly typed
math constants.

Main benefits:
- portable and
- returns constexpr, for compile-time computation

References:
- http://www.boost.org/doc/libs/1_60_0/libs/math/doc/html/math_toolkit/constants_intro.html
- http://www.boost.org/doc/libs/1_60_0/libs/math/doc/html/math_toolkit/constants.html
This commit is contained in:
Daniel J. Hofmann 2016-01-28 15:21:02 +01:00
parent 64b36807d3
commit ef171f3acd
6 changed files with 42 additions and 26 deletions

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@ -163,7 +163,6 @@ elseif(${CMAKE_CXX_COMPILER_ID} STREQUAL "GNU")
# using GCC
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -Wextra -pedantic -Wuninitialized -Wunreachable-code -Wstrict-overflow=1 -D_FORTIFY_SOURCE=2 ${COLOR_FLAG} -fPIC")
if(WIN32) # using mingw
add_definitions(-D_USE_MATH_DEFINES) # define M_PI, M_1_PI etc.
add_definitions(-DWIN32)
set(OPTIONAL_SOCKET_LIBS ws2_32 wsock32)
endif()
@ -175,7 +174,6 @@ elseif(${CMAKE_CXX_COMPILER_ID} STREQUAL "MSVC")
set(BOOST_COMPONENTS ${BOOST_COMPONENTS} date_time chrono zlib)
add_definitions(-D_CRT_SECURE_NO_WARNINGS)
add_definitions(-DNOMINMAX) # avoid min and max macros that can break compilation
add_definitions(-D_USE_MATH_DEFINES) # define M_PI
add_definitions(-D_WIN32_WINNT=0x0501)
add_definitions(-DXML_STATIC)
find_library(ws2_32_LIBRARY_PATH ws2_32)

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@ -6,6 +6,8 @@
#include <vector>
#include <utility>
#include <boost/math/constants/constants.hpp>
namespace osrm
{
namespace engine
@ -23,8 +25,10 @@ struct NormalDistribution
// FIXME implement log-probability version since its faster
double density_function(const double val) const
{
using namespace boost::math::constants;
const double x = val - mean;
return 1.0 / (std::sqrt(2. * M_PI) * standard_deviation) *
return 1.0 / (std::sqrt(two_pi<double>()) * standard_deviation) *
std::exp(-x * x / (standard_deviation * standard_deviation));
}

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@ -4,6 +4,7 @@
#include "util/integer_range.hpp"
#include <boost/assert.hpp>
#include <boost/math/constants/constants.hpp>
#include <cmath>
@ -17,7 +18,7 @@ namespace engine
namespace map_matching
{
static const double log_2_pi = std::log(2. * M_PI);
static const double log_2_pi = std::log(2. * boost::math::constants::pi<double>());
static const double IMPOSSIBLE_LOG_PROB = -std::numeric_limits<double>::infinity();
static const double MINIMAL_LOG_PROB = std::numeric_limits<double>::lowest();
static const std::size_t INVALID_STATE = std::numeric_limits<std::size_t>::max();

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@ -6,6 +6,8 @@
#include <limits>
#include <boost/math/constants/constants.hpp>
namespace osrm
{
namespace util
@ -356,19 +358,22 @@ constexpr unsigned short atan_table[4096] = {
0xffe0, 0xffea, 0xfff4, 0xffff};
// max value is pi/4
constexpr double SCALING_FACTOR = 4. / M_PI * 0xFFFF;
const constexpr double SCALING_FACTOR = 4. / boost::math::constants::pi<double>() * 0xFFFF;
inline double atan2_lookup(double y, double x)
{
using namespace boost::math::constants;
if (std::abs(x) < std::numeric_limits<double>::epsilon())
{
if (y >= 0.)
{
return M_PI / 2.;
return half_pi<double>();
}
else
{
return -M_PI / 2.;
return -half_pi<double>();
}
}
@ -399,25 +404,25 @@ inline double atan2_lookup(double y, double x)
case 0:
break;
case 1:
angle = M_PI - angle;
angle = pi<double>() - angle;
break;
case 2:
angle = -angle;
break;
case 3:
angle = -M_PI + angle;
angle = -pi<double>() + angle;
break;
case 4:
angle = M_PI / 2.0 - angle;
angle = half_pi<double>() - angle;
break;
case 5:
angle = M_PI / 2.0 + angle;
angle = half_pi<double>() + angle;
break;
case 6:
angle = -M_PI / 2.0 + angle;
angle = -half_pi<double>() + angle;
break;
case 7:
angle = -M_PI / 2.0 - angle;
angle = -half_pi<double>() - angle;
break;
}
return angle;

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@ -6,14 +6,6 @@
#include <limits>
#include <cstddef>
// Necessary workaround for Windows as VS doesn't implement C99
#ifdef _MSC_VER
#define WIN32_LEAN_AND_MEAN
#ifndef M_PI
#define M_PI 3.14159265358979323846
#endif
#endif
// OpenStreetMap node ids are higher than 2^32
OSRM_STRONG_TYPEDEF(uint64_t, OSMNodeID)
OSRM_STRONG_TYPEDEF(uint32_t, OSMWayID)

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@ -4,6 +4,7 @@
#include "util/trigonometry_table.hpp"
#include <boost/assert.hpp>
#include <boost/math/constants/constants.hpp>
#include <cmath>
@ -193,9 +194,17 @@ perpendicularDistanceFromProjectedCoordinate(const FixedPointCoordinate segment_
return approximate_distance;
}
double degToRad(const double degree) { return degree * (static_cast<double>(M_PI) / 180.0); }
double degToRad(const double degree)
{
using namespace boost::math::constants;
return degree * (pi<double>() / 180.0);
}
double radToDeg(const double radian) { return radian * (180.0 * static_cast<double>(M_1_PI)); }
double radToDeg(const double radian)
{
using namespace boost::math::constants;
return radian * (180.0 * (1. / pi<double>()));
}
double bearing(const FixedPointCoordinate first_coordinate,
const FixedPointCoordinate second_coordinate)
@ -225,6 +234,7 @@ double computeAngle(const FixedPointCoordinate first,
const FixedPointCoordinate second,
const FixedPointCoordinate third)
{
using namespace boost::math::constants;
using namespace coordinate_calculation;
const double v1x = (first.lon - second.lon) / COORDINATE_PRECISION;
@ -234,7 +244,7 @@ double computeAngle(const FixedPointCoordinate first,
const double v2y = mercator::latToY(third.lat / COORDINATE_PRECISION) -
mercator::latToY(second.lat / COORDINATE_PRECISION);
double angle = (atan2_lookup(v2y, v2x) - atan2_lookup(v1y, v1x)) * 180. / M_PI;
double angle = (atan2_lookup(v2y, v2x) - atan2_lookup(v1y, v1x)) * 180. / pi<double>();
while (angle < 0.)
{
@ -248,12 +258,18 @@ namespace mercator
{
double yToLat(const double value)
{
return 180. * M_1_PI * (2. * std::atan(std::exp(value * M_PI / 180.)) - M_PI_2);
using namespace boost::math::constants;
return 180. * (1. / pi<long double>()) *
(2. * std::atan(std::exp(value * pi<double>() / 180.)) - half_pi<double>());
}
double latToY(const double latitude)
{
return 180. * M_1_PI * std::log(std::tan(M_PI_4 + latitude * (M_PI / 180.) / 2.));
using namespace boost::math::constants;
return 180. * (1. / pi<double>()) *
std::log(std::tan((pi<double>() / 4.) + latitude * (pi<double>() / 180.) / 2.));
}
} // ns mercato // ns mercatorr
} // ns coordinate_calculation