285 lines
8.7 KiB
C++
285 lines
8.7 KiB
C++
// Boost.Geometry (aka GGL, Generic Geometry Library)
|
|
|
|
// Copyright (c) 2008-2014 Bruno Lalande, Paris, France.
|
|
// Copyright (c) 2008-2014 Barend Gehrels, Amsterdam, the Netherlands.
|
|
// Copyright (c) 2009-2014 Mateusz Loskot, London, UK.
|
|
|
|
// This file was modified by Oracle on 2014-2021.
|
|
// Modifications copyright (c) 2014-2021, Oracle and/or its affiliates.
|
|
// Contributed and/or modified by Menelaos Karavelas, on behalf of Oracle
|
|
// Contributed and/or modified by Adam Wulkiewicz, on behalf of Oracle
|
|
|
|
// Parts of Boost.Geometry are redesigned from Geodan's Geographic Library
|
|
// (geolib/GGL), copyright (c) 1995-2010 Geodan, Amsterdam, the Netherlands.
|
|
|
|
// 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_STRATEGIES_CARTESIAN_DISTANCE_PROJECTED_POINT_HPP
|
|
#define BOOST_GEOMETRY_STRATEGIES_CARTESIAN_DISTANCE_PROJECTED_POINT_HPP
|
|
|
|
|
|
#include <type_traits>
|
|
|
|
#include <boost/concept_check.hpp>
|
|
#include <boost/core/ignore_unused.hpp>
|
|
|
|
#include <boost/geometry/core/access.hpp>
|
|
#include <boost/geometry/core/point_type.hpp>
|
|
|
|
#include <boost/geometry/algorithms/convert.hpp>
|
|
#include <boost/geometry/arithmetic/arithmetic.hpp>
|
|
#include <boost/geometry/arithmetic/dot_product.hpp>
|
|
|
|
#include <boost/geometry/strategies/tags.hpp>
|
|
#include <boost/geometry/strategies/distance.hpp>
|
|
#include <boost/geometry/strategies/default_distance_result.hpp>
|
|
#include <boost/geometry/strategies/cartesian/distance_pythagoras.hpp>
|
|
#include <boost/geometry/strategies/cartesian/point_in_point.hpp>
|
|
#include <boost/geometry/strategies/cartesian/intersection.hpp>
|
|
|
|
// Helper geometry (projected point on line)
|
|
#include <boost/geometry/geometries/point.hpp>
|
|
|
|
|
|
namespace boost { namespace geometry
|
|
{
|
|
|
|
|
|
namespace strategy { namespace distance
|
|
{
|
|
|
|
/*!
|
|
\brief Strategy for distance point to segment
|
|
\ingroup strategies
|
|
\details Calculates distance using projected-point method, and (optionally) Pythagoras
|
|
\author Adapted from: http://geometryalgorithms.com/Archive/algorithm_0102/algorithm_0102.htm
|
|
\tparam CalculationType \tparam_calculation
|
|
\tparam Strategy underlying point-point distance strategy
|
|
\par Concepts for Strategy:
|
|
- cartesian_distance operator(Point,Point)
|
|
\note If the Strategy is a "comparable::pythagoras", this strategy
|
|
automatically is a comparable projected_point strategy (so without sqrt)
|
|
|
|
\qbk{
|
|
[heading See also]
|
|
[link geometry.reference.algorithms.distance.distance_3_with_strategy distance (with strategy)]
|
|
}
|
|
|
|
*/
|
|
template
|
|
<
|
|
typename CalculationType = void,
|
|
typename Strategy = pythagoras<CalculationType>
|
|
>
|
|
class projected_point
|
|
{
|
|
public:
|
|
// The three typedefs below are necessary to calculate distances
|
|
// from segments defined in integer coordinates.
|
|
|
|
// Integer coordinates can still result in FP distances.
|
|
// There is a division, which must be represented in FP.
|
|
// So promote.
|
|
template <typename Point, typename PointOfSegment>
|
|
struct calculation_type
|
|
: promote_floating_point
|
|
<
|
|
typename strategy::distance::services::return_type
|
|
<
|
|
Strategy,
|
|
Point,
|
|
PointOfSegment
|
|
>::type
|
|
>
|
|
{};
|
|
|
|
template <typename Point, typename PointOfSegment>
|
|
inline typename calculation_type<Point, PointOfSegment>::type
|
|
apply(Point const& p, PointOfSegment const& p1, PointOfSegment const& p2) const
|
|
{
|
|
assert_dimension_equal<Point, PointOfSegment>();
|
|
|
|
typedef typename calculation_type<Point, PointOfSegment>::type calculation_type;
|
|
|
|
// A projected point of points in Integer coordinates must be able to be
|
|
// represented in FP.
|
|
typedef model::point
|
|
<
|
|
calculation_type,
|
|
dimension<PointOfSegment>::value,
|
|
typename coordinate_system<PointOfSegment>::type
|
|
> fp_point_type;
|
|
|
|
// For convenience
|
|
typedef fp_point_type fp_vector_type;
|
|
|
|
/*
|
|
Algorithm [p: (px,py), p1: (x1,y1), p2: (x2,y2)]
|
|
VECTOR v(x2 - x1, y2 - y1)
|
|
VECTOR w(px - x1, py - y1)
|
|
c1 = w . v
|
|
c2 = v . v
|
|
b = c1 / c2
|
|
RETURN POINT(x1 + b * vx, y1 + b * vy)
|
|
*/
|
|
|
|
// v is multiplied below with a (possibly) FP-value, so should be in FP
|
|
// For consistency we define w also in FP
|
|
fp_vector_type v, w, projected;
|
|
|
|
geometry::convert(p2, v);
|
|
geometry::convert(p, w);
|
|
geometry::convert(p1, projected);
|
|
subtract_point(v, projected);
|
|
subtract_point(w, projected);
|
|
|
|
Strategy strategy;
|
|
boost::ignore_unused(strategy);
|
|
|
|
calculation_type const zero = calculation_type();
|
|
calculation_type const c1 = dot_product(w, v);
|
|
if (c1 <= zero)
|
|
{
|
|
return strategy.apply(p, p1);
|
|
}
|
|
calculation_type const c2 = dot_product(v, v);
|
|
if (c2 <= c1)
|
|
{
|
|
return strategy.apply(p, p2);
|
|
}
|
|
|
|
// See above, c1 > 0 AND c2 > c1 so: c2 != 0
|
|
calculation_type const b = c1 / c2;
|
|
|
|
multiply_value(v, b);
|
|
add_point(projected, v);
|
|
|
|
return strategy.apply(p, projected);
|
|
}
|
|
|
|
template <typename CT>
|
|
inline CT vertical_or_meridian(CT const& lat1, CT const& lat2) const
|
|
{
|
|
return lat1 - lat2;
|
|
}
|
|
|
|
};
|
|
|
|
#ifndef DOXYGEN_NO_STRATEGY_SPECIALIZATIONS
|
|
namespace services
|
|
{
|
|
|
|
template <typename CalculationType, typename Strategy>
|
|
struct tag<projected_point<CalculationType, Strategy> >
|
|
{
|
|
typedef strategy_tag_distance_point_segment type;
|
|
};
|
|
|
|
|
|
template <typename CalculationType, typename Strategy, typename P, typename PS>
|
|
struct return_type<projected_point<CalculationType, Strategy>, P, PS>
|
|
: projected_point<CalculationType, Strategy>::template calculation_type<P, PS>
|
|
{};
|
|
|
|
|
|
|
|
template <typename CalculationType, typename Strategy>
|
|
struct comparable_type<projected_point<CalculationType, Strategy> >
|
|
{
|
|
// Define a projected_point strategy with its underlying point-point-strategy
|
|
// being comparable
|
|
typedef projected_point
|
|
<
|
|
CalculationType,
|
|
typename comparable_type<Strategy>::type
|
|
> type;
|
|
};
|
|
|
|
|
|
template <typename CalculationType, typename Strategy>
|
|
struct get_comparable<projected_point<CalculationType, Strategy> >
|
|
{
|
|
typedef typename comparable_type
|
|
<
|
|
projected_point<CalculationType, Strategy>
|
|
>::type comparable_type;
|
|
public :
|
|
static inline comparable_type apply(projected_point<CalculationType, Strategy> const& )
|
|
{
|
|
return comparable_type();
|
|
}
|
|
};
|
|
|
|
|
|
template <typename CalculationType, typename Strategy, typename P, typename PS>
|
|
struct result_from_distance<projected_point<CalculationType, Strategy>, P, PS>
|
|
{
|
|
private :
|
|
typedef typename return_type<projected_point<CalculationType, Strategy>, P, PS>::type return_type;
|
|
public :
|
|
template <typename T>
|
|
static inline return_type apply(projected_point<CalculationType, Strategy> const& , T const& value)
|
|
{
|
|
Strategy s;
|
|
return result_from_distance<Strategy, P, PS>::apply(s, value);
|
|
}
|
|
};
|
|
|
|
|
|
// Get default-strategy for point-segment distance calculation
|
|
// while still have the possibility to specify point-point distance strategy (PPS)
|
|
// It is used in algorithms/distance.hpp where users specify PPS for distance
|
|
// of point-to-segment or point-to-linestring.
|
|
// Convenient for geographic coordinate systems especially.
|
|
template <typename Point, typename PointOfSegment, typename Strategy>
|
|
struct default_strategy
|
|
<
|
|
point_tag, segment_tag, Point, PointOfSegment,
|
|
cartesian_tag, cartesian_tag, Strategy
|
|
>
|
|
{
|
|
typedef strategy::distance::projected_point
|
|
<
|
|
void,
|
|
std::conditional_t
|
|
<
|
|
std::is_void<Strategy>::value,
|
|
typename default_strategy
|
|
<
|
|
point_tag, point_tag, Point, PointOfSegment,
|
|
cartesian_tag, cartesian_tag
|
|
>::type,
|
|
Strategy
|
|
>
|
|
> type;
|
|
};
|
|
|
|
template <typename PointOfSegment, typename Point, typename Strategy>
|
|
struct default_strategy
|
|
<
|
|
segment_tag, point_tag, PointOfSegment, Point,
|
|
cartesian_tag, cartesian_tag, Strategy
|
|
>
|
|
{
|
|
typedef typename default_strategy
|
|
<
|
|
point_tag, segment_tag, Point, PointOfSegment,
|
|
cartesian_tag, cartesian_tag, Strategy
|
|
>::type type;
|
|
};
|
|
|
|
|
|
} // namespace services
|
|
#endif // DOXYGEN_NO_STRATEGY_SPECIALIZATIONS
|
|
|
|
|
|
}} // namespace strategy::distance
|
|
|
|
|
|
}} // namespace boost::geometry
|
|
|
|
|
|
#endif // BOOST_GEOMETRY_STRATEGIES_CARTESIAN_DISTANCE_PROJECTED_POINT_HPP
|