mirror of
https://github.com/boostorg/geometry.git
synced 2026-02-11 11:52:11 +00:00
[disjoint] add alternative (more robust) implementation of segment-box disjointness test; the alternative implementation does not use any divisions
This commit is contained in:
Menelaos Karavelas
@@ -0,0 +1,263 @@
|
||||
// Boost.Geometry (aka GGL, Generic Geometry Library)
|
||||
|
||||
// Copyright (c) 2014, Oracle and/or its affiliates.
|
||||
|
||||
// Contributed and/or modified by Menelaos Karavelas, on behalf of Oracle
|
||||
|
||||
// Licensed under the Boost Software License version 1.0.
|
||||
// http://www.boost.org/users/license.html
|
||||
|
||||
#ifndef BOOST_GEOMETRY_ALGORITHMS_DETAIL_DISJOINT_SEGMENT_BOX_HPP
|
||||
#define BOOST_GEOMETRY_ALGORITHMS_DETAIL_DISJOINT_SEGMENT_BOX_HPP
|
||||
|
||||
#include <cstddef>
|
||||
#include <utility>
|
||||
|
||||
#include <boost/geometry/util/calculation_type.hpp>
|
||||
|
||||
#include <boost/geometry/core/access.hpp>
|
||||
#include <boost/geometry/core/coordinate_dimension.hpp>
|
||||
#include <boost/geometry/core/point_type.hpp>
|
||||
|
||||
#include <boost/geometry/algorithms/detail/assign_indexed_point.hpp>
|
||||
|
||||
|
||||
namespace boost { namespace geometry
|
||||
{
|
||||
|
||||
|
||||
#ifndef DOXYGEN_NO_DETAIL
|
||||
namespace detail { namespace disjoint
|
||||
{
|
||||
|
||||
|
||||
|
||||
template
|
||||
<
|
||||
typename RelativeDistance,
|
||||
typename SegmentPoint,
|
||||
typename Box,
|
||||
std::size_t I,
|
||||
std::size_t Dimension
|
||||
>
|
||||
struct disjoint_segment_box_impl
|
||||
{
|
||||
template <typename RelativeDistancePair>
|
||||
static inline bool apply(SegmentPoint const& p0,
|
||||
SegmentPoint const& p1,
|
||||
Box const& box,
|
||||
RelativeDistancePair& t_min,
|
||||
RelativeDistancePair& t_max)
|
||||
{
|
||||
typedef typename coordinate_type<Box>::type box_coordinate_type;
|
||||
typedef typename coordinate_type
|
||||
<
|
||||
SegmentPoint
|
||||
>::type point_coordinate_type;
|
||||
|
||||
RelativeDistance c_p0 = boost::numeric_cast
|
||||
<
|
||||
point_coordinate_type
|
||||
>( geometry::get<I>(p0) );
|
||||
|
||||
RelativeDistance c_p1 = boost::numeric_cast
|
||||
<
|
||||
point_coordinate_type
|
||||
>( geometry::get<I>(p1) );
|
||||
|
||||
RelativeDistance c_b_min = boost::numeric_cast
|
||||
<
|
||||
box_coordinate_type
|
||||
>( geometry::get<geometry::min_corner, I>(box) );
|
||||
|
||||
RelativeDistance c_b_max = boost::numeric_cast
|
||||
<
|
||||
box_coordinate_type
|
||||
>( geometry::get<geometry::max_corner, I>(box) );
|
||||
|
||||
RelativeDistance ti_min, ti_max, diff;
|
||||
|
||||
if ( geometry::get<I>(p1) >= geometry::get<I>(p0) )
|
||||
{
|
||||
diff = c_p1 - c_p0;
|
||||
ti_min = c_b_min - c_p0;
|
||||
ti_max = c_b_max - c_p0;
|
||||
}
|
||||
else
|
||||
{
|
||||
diff = c_p0 - c_p1;
|
||||
ti_min = c_p0 - c_b_max;
|
||||
ti_max = c_p0 - c_b_min;
|
||||
}
|
||||
|
||||
RelativeDistance t_min_x_diff = t_min.first * diff;
|
||||
RelativeDistance t_max_x_diff = t_max.first * diff;
|
||||
|
||||
if ( t_min_x_diff > ti_max * t_min.second
|
||||
|| t_max_x_diff < ti_min * t_max.second )
|
||||
{
|
||||
return true;
|
||||
}
|
||||
|
||||
if ( ti_min * t_min.second > t_min_x_diff )
|
||||
{
|
||||
t_min.first = ti_min;
|
||||
t_min.second = diff;
|
||||
}
|
||||
if ( ti_max * t_max.second < t_max_x_diff )
|
||||
{
|
||||
t_max.first = ti_max;
|
||||
t_max.second = diff;
|
||||
}
|
||||
|
||||
if ( t_min.first > t_min.second || t_max.first < 0 )
|
||||
{
|
||||
return true;
|
||||
}
|
||||
|
||||
return disjoint_segment_box_impl
|
||||
<
|
||||
RelativeDistance,
|
||||
SegmentPoint,
|
||||
Box,
|
||||
I + 1,
|
||||
Dimension
|
||||
>::apply(p0, p1, box, t_min, t_max);
|
||||
}
|
||||
};
|
||||
|
||||
|
||||
template
|
||||
<
|
||||
typename RelativeDistance,
|
||||
typename SegmentPoint,
|
||||
typename Box,
|
||||
std::size_t Dimension
|
||||
>
|
||||
struct disjoint_segment_box_impl
|
||||
<
|
||||
RelativeDistance, SegmentPoint, Box, 0, Dimension
|
||||
>
|
||||
{
|
||||
static inline bool apply(SegmentPoint const& p0,
|
||||
SegmentPoint const& p1,
|
||||
Box const& box)
|
||||
{
|
||||
typedef typename coordinate_type<Box>::type box_coordinate_type;
|
||||
typedef typename coordinate_type
|
||||
<
|
||||
SegmentPoint
|
||||
>::type point_coordinate_type;
|
||||
|
||||
RelativeDistance c_p0 = boost::numeric_cast
|
||||
<
|
||||
point_coordinate_type
|
||||
>( geometry::get<0>(p0) );
|
||||
|
||||
RelativeDistance c_p1 = boost::numeric_cast
|
||||
<
|
||||
point_coordinate_type
|
||||
>( geometry::get<0>(p1) );
|
||||
|
||||
RelativeDistance c_b_min = boost::numeric_cast
|
||||
<
|
||||
box_coordinate_type
|
||||
>( geometry::get<geometry::min_corner, 0>(box) );
|
||||
|
||||
RelativeDistance c_b_max = boost::numeric_cast
|
||||
<
|
||||
box_coordinate_type
|
||||
>( geometry::get<geometry::max_corner, 0>(box) );
|
||||
|
||||
std::pair<RelativeDistance, RelativeDistance> t_min, t_max;
|
||||
|
||||
RelativeDistance diff;
|
||||
|
||||
if ( geometry::get<0>(p1) >= geometry::get<0>(p0) )
|
||||
{
|
||||
diff = c_p1 - c_p0;
|
||||
t_min.first = c_b_min - c_p0;
|
||||
t_max.first = c_b_max - c_p0;
|
||||
}
|
||||
else
|
||||
{
|
||||
diff = c_p0 - c_p1;
|
||||
t_min.first = c_p0 - c_b_max;
|
||||
t_max.first = c_p0 - c_b_min;
|
||||
}
|
||||
|
||||
if ( t_min.first > diff || t_max.first < 0 )
|
||||
{
|
||||
return true;
|
||||
}
|
||||
|
||||
t_min.second = t_max.second = diff;
|
||||
|
||||
return disjoint_segment_box_impl
|
||||
<
|
||||
RelativeDistance, SegmentPoint, Box, 1, Dimension
|
||||
>::apply(p0, p1, box, t_min, t_max);
|
||||
}
|
||||
};
|
||||
|
||||
|
||||
template
|
||||
<
|
||||
typename RelativeDistance,
|
||||
typename SegmentPoint,
|
||||
typename Box,
|
||||
std::size_t Dimension
|
||||
>
|
||||
struct disjoint_segment_box_impl
|
||||
<
|
||||
RelativeDistance, SegmentPoint, Box, Dimension, Dimension
|
||||
>
|
||||
{
|
||||
template <typename RelativeDistancePair>
|
||||
static inline bool apply(SegmentPoint const&, SegmentPoint const&,
|
||||
Box const&,
|
||||
RelativeDistancePair&, RelativeDistancePair&)
|
||||
{
|
||||
return false;
|
||||
}
|
||||
};
|
||||
|
||||
|
||||
//=========================================================================
|
||||
|
||||
|
||||
template <typename Segment, typename Box>
|
||||
struct disjoint_segment_box_no_numeric_limits
|
||||
{
|
||||
static inline bool apply(Segment const& segment, Box const& box)
|
||||
{
|
||||
assert_dimension_equal<Segment, Box>();
|
||||
|
||||
typedef typename util::calculation_type::geometric::binary
|
||||
<
|
||||
Segment, Box, void
|
||||
>::type relative_distance_type;
|
||||
|
||||
typedef typename point_type<Segment>::type segment_point_type;
|
||||
segment_point_type p0, p1;
|
||||
geometry::detail::assign_point_from_index<0>(segment, p0);
|
||||
geometry::detail::assign_point_from_index<1>(segment, p1);
|
||||
|
||||
return disjoint_segment_box_impl
|
||||
<
|
||||
relative_distance_type, segment_point_type, Box,
|
||||
0, dimension<Box>::value
|
||||
>::apply(p0, p1, box);
|
||||
}
|
||||
};
|
||||
|
||||
|
||||
}} // namespace detail::disjoint
|
||||
#endif // DOXYGEN_NO_DETAIL
|
||||
|
||||
|
||||
|
||||
}} // namespace boost::geometry
|
||||
|
||||
|
||||
#endif // BOOST_GEOMETRY_ALGORITHMS_DETAIL_DISJOINT_SEGMENT_BOX_HPP
|
||||
Reference in New Issue
Block a user