[formulas] Add thomas_direct and move result_direct into separate file.

This commit is contained in:
Adam Wulkiewicz
2016-07-15 03:05:02 +02:00
parent 86932c34e2
commit 50d9fe37d8
4 changed files with 214 additions and 22 deletions

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@@ -0,0 +1,39 @@
// Boost.Geometry
// Copyright (c) 2016 Oracle and/or its affiliates.
// Contributed and/or modified by Adam Wulkiewicz, on behalf of Oracle
// Use, modification and distribution is subject to the Boost Software License,
// Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
#ifndef BOOST_GEOMETRY_FORMULAS_RESULT_DIRECT_HPP
#define BOOST_GEOMETRY_FORMULAS_RESULT_DIRECT_HPP
namespace boost { namespace geometry { namespace formula
{
template <typename T>
struct result_direct
{
result_direct()
: lon2(0)
, lat2(0)
, reverse_azimuth(0)
, reduced_length(0)
, geodesic_scale(1)
{}
T lon2;
T lat2;
T reverse_azimuth;
T reduced_length;
T geodesic_scale;
};
}}} // namespace boost::geometry::formula
#endif // BOOST_GEOMETRY_FORMULAS_RESULT_DIRECT_HPP

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@@ -0,0 +1,168 @@
// Boost.Geometry
// Copyright (c) 2016 Oracle and/or its affiliates.
// Contributed and/or modified by Adam Wulkiewicz, on behalf of Oracle
// Use, modification and distribution is subject to the Boost Software License,
// Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
#ifndef BOOST_GEOMETRY_FORMULAS_THOMAS_DIRECT_HPP
#define BOOST_GEOMETRY_FORMULAS_THOMAS_DIRECT_HPP
#include <boost/math/constants/constants.hpp>
#include <boost/geometry/core/radius.hpp>
#include <boost/geometry/core/srs.hpp>
#include <boost/geometry/util/condition.hpp>
#include <boost/geometry/util/math.hpp>
#include <boost/geometry/algorithms/detail/flattening.hpp>
#include <boost/geometry/formulas/differential_quantities.hpp>
#include <boost/geometry/formulas/result_direct.hpp>
namespace boost { namespace geometry { namespace formula
{
/*!
\brief The solution of the direct problem of geodesics on latlong coordinates,
Forsyth-Andoyer-Lambert type approximation with second order terms.
\author See
- Technical Report: PAUL D. THOMAS, MATHEMATICAL MODELS FOR NAVIGATION SYSTEMS, 1965
http://www.dtic.mil/docs/citations/AD0627893
- Technical Report: PAUL D. THOMAS, SPHEROIDAL GEODESICS, REFERENCE SYSTEMS, AND LOCAL GEOMETRY, 1970
http://www.dtic.mil/docs/citations/AD0703541
*/
template <
typename CT,
bool EnableCoordinates = true,
bool EnableReverseAzimuth = false,
bool EnableReducedLength = false,
bool EnableGeodesicScale = false
>
class thomas_direct
{
static const bool CalcQuantities = EnableReducedLength || EnableGeodesicScale;
static const bool CalcCoordinates = EnableCoordinates || CalcQuantities;
static const bool CalcRevAzimuth = EnableReverseAzimuth || CalcCoordinates || CalcQuantities;
public:
typedef result_direct<CT> result_type;
template <typename T, typename Dist, typename Azi, typename Spheroid>
static inline result_type apply(T const& lo1,
T const& la1,
Dist const& distance,
Azi const& azimuth12,
Spheroid const& spheroid)
{
result_type result;
CT const lon1 = lo1;
CT const lat1 = la1;
if ( math::equals(distance, Dist(0)) || distance < Dist(0) )
{
result.lon2 = lon1;
result.lat2 = lat1;
return result;
}
CT const c0 = 0;
CT const c1 = 1;
CT const c2 = 2;
CT const c4 = 4;
CT const a = CT(get_radius<0>(spheroid));
CT const b = CT(get_radius<2>(spheroid));
CT const f = detail::flattening<CT>(spheroid);
CT const one_minus_f = c1 - f;
CT const pi_half = math::pi<CT>() / c2;
CT const theta1 = math::equals(lat1, pi_half) ? lat1 :
math::equals(lat1, -pi_half) ? lat1 :
atan(one_minus_f * tan(lat1));
CT const sin_theta1 = sin(theta1);
CT const cos_theta1 = cos(theta1);
CT const sin_a12 = sin(azimuth12);
CT const cos_a12 = cos(azimuth12);
CT const M = cos_theta1 * sin_a12; // cos_theta0
CT const theta0 = acos(M);
CT const sin_theta0 = sin(theta0);
CT const N = cos_theta1 * cos_a12;
CT const C1 = f * M; // lower-case c1 in the technical report
CT const C2 = f * (c1 - math::sqr(M)) / c4; // lower-case c2 in the technical report
CT const D = (c1 - C2) * (c1 - C2 - C1 * M);
CT const P = C2 * (c1 + C1 * M / c2) / D;
CT const cos_sigma1 = sin_theta1 / sin_theta0;
CT const sigma1 = acos(cos_sigma1);
CT const d = distance / (a * D);
CT const u = 2 * (sigma1 - d);
CT const sin_sigma1 = sin(sigma1);
CT const cos_d = cos(d);
CT const sin_d = sin(d);
CT const cos_u = cos(u);
CT const sin_u = sin(u);
CT const W = c1 - c2 * P * cos_u;
CT const V = cos_u * cos_d - sin_u * sin_d;
CT const X = math::sqr(C2) * sin_d * cos_d * (2 * math::sqr(V) - c1);
CT const Y = c2 * P * V * W * sin_d;
CT const d_sigma = d + X - Y;
CT const sin_d_sigma = sin(d_sigma);
CT const cos_d_sigma = cos(d_sigma);
if (BOOST_GEOMETRY_CONDITION(CalcRevAzimuth))
{
result.reverse_azimuth = atan2(M, N * cos_d_sigma - sin_theta1 * sin_d_sigma);
}
if (BOOST_GEOMETRY_CONDITION(CalcCoordinates))
{
CT const sin_a21 = sin(result.reverse_azimuth);
CT const cos_a21 = cos(result.reverse_azimuth);
CT const tan_lat2 = (sin_theta1 * cos_d_sigma + N * sin_d_sigma) * sin_a21 / (one_minus_f * M);
result.lat2 = atan(tan_lat2);
CT const S_sigma = c2 * sigma1 - d_sigma;
CT const cos_S_sigma = cos(S_sigma);
CT const d_eta = atan2(sin_d_sigma * sin_a12, cos_theta1 * cos_d_sigma - sin_theta1 * sin_d_sigma * cos_a12);
CT const H = C1 * (c1 - C2) * d_sigma - C1 * C2 * sin_d_sigma * cos_S_sigma;
CT const d_lambda = d_eta - H;
result.lon2 = lon1 + d_lambda;
}
if (BOOST_GEOMETRY_CONDITION(CalcQuantities))
{
typedef differential_quantities<CT, EnableReducedLength, EnableGeodesicScale> quantities;
quantities::apply(lon1, lat1, result.lon2, result.lat2,
azimuth12, result.reverse_azimuth,
b, f,
result.reduced_length, result.geodesic_scale,
quantities::J12_calc_f2);
}
return result;
}
};
}}} // namespace boost::geometry::formula
#endif // BOOST_GEOMETRY_FORMULAS_THOMAS_DIRECT_HPP

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@@ -36,7 +36,7 @@ namespace boost { namespace geometry { namespace formula
- Technical Report: PAUL D. THOMAS, MATHEMATICAL MODELS FOR NAVIGATION SYSTEMS, 1965
http://www.dtic.mil/docs/citations/AD0627893
- Technical Report: PAUL D. THOMAS, SPHEROIDAL GEODESICS, REFERENCE SYSTEMS, AND LOCAL GEOMETRY, 1970
http://www.dtic.mil/docs/citations/AD703541
http://www.dtic.mil/docs/citations/AD0703541
*/
template <
typename CT,
@@ -63,11 +63,6 @@ public:
T2 const& lat2,
Spheroid const& spheroid)
{
CT const c0 = 0;
CT const c1 = 1;
CT const c2 = 2;
CT const c4 = 4;
result_type result;
// coordinates in radians
@@ -77,6 +72,11 @@ public:
return result;
}
CT const c0 = 0;
CT const c1 = 1;
CT const c2 = 2;
CT const c4 = 4;
CT const pi_half = math::pi<CT>() / c2;
CT const f = detail::flattening<CT>(spheroid);
CT const one_minus_f = c1 - f;

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@@ -26,6 +26,7 @@
#include <boost/geometry/algorithms/detail/flattening.hpp>
#include <boost/geometry/formulas/differential_quantities.hpp>
#include <boost/geometry/formulas/result_direct.hpp>
#ifndef BOOST_GEOMETRY_DETAIL_VINCENTY_MAX_STEPS
@@ -36,22 +37,6 @@
namespace boost { namespace geometry { namespace formula
{
template <typename T>
struct result_direct
{
result_direct()
: lon2(0)
, lat2(0)
, reverse_azimuth(0)
{}
T lon2;
T lat2;
T reverse_azimuth;
T reduced_length;
T geodesic_scale;
};
/*!
\brief The solution of the direct problem of geodesics on latlong coordinates, after Vincenty, 1975
\author See