vn-verdnaturachat/ios/Pods/boost-for-react-native/boost/polygon/segment_utils.hpp

165 lines
5.0 KiB
C++

/*
Copyright 2012 Lucanus Simonson
Use, modification and distribution are 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_POLYGON_SEGMENT_UTILS_HPP
#define BOOST_POLYGON_SEGMENT_UTILS_HPP
#include <iterator>
#include <set>
#include <vector>
#include "detail/scan_arbitrary.hpp"
#include "isotropy.hpp"
#include "rectangle_concept.hpp"
#include "segment_concept.hpp"
namespace boost {
namespace polygon {
template <typename Segment, typename SegmentIterator>
typename enable_if<
typename gtl_and<
typename gtl_if<
typename is_segment_concept<
typename geometry_concept<
typename std::iterator_traits<SegmentIterator>::value_type
>::type
>::type
>::type,
typename gtl_if<
typename is_segment_concept<
typename geometry_concept<Segment>::type
>::type
>::type
>::type,
void
>::type
intersect_segments(
std::vector<std::pair<std::size_t, Segment> >& result,
SegmentIterator first, SegmentIterator last) {
typedef typename segment_traits<Segment>::coordinate_type Unit;
typedef typename scanline_base<Unit>::Point Point;
typedef typename scanline_base<Unit>::half_edge half_edge;
typedef int segment_id;
std::vector<std::pair<half_edge, segment_id> > half_edges;
std::vector<std::pair<half_edge, segment_id> > half_edges_out;
segment_id id_in = 0;
half_edges.reserve(std::distance(first, last));
for (; first != last; ++first) {
Point l, h;
assign(l, low(*first));
assign(h, high(*first));
half_edges.push_back(std::make_pair(half_edge(l, h), id_in++));
}
half_edges_out.reserve(half_edges.size());
// Apparently no need to pre-sort data when calling validate_scan.
if (half_edges.size() != 0) {
line_intersection<Unit>::validate_scan(
half_edges_out, half_edges.begin(), half_edges.end());
}
result.reserve(result.size() + half_edges_out.size());
for (std::size_t i = 0; i < half_edges_out.size(); ++i) {
std::size_t id = (std::size_t)(half_edges_out[i].second);
Point l = half_edges_out[i].first.first;
Point h = half_edges_out[i].first.second;
result.push_back(std::make_pair(id, construct<Segment>(l, h)));
}
}
template <typename SegmentContainer, typename SegmentIterator>
typename enable_if<
typename gtl_and<
typename gtl_if<
typename is_segment_concept<
typename geometry_concept<
typename std::iterator_traits<SegmentIterator>::value_type
>::type
>::type
>::type,
typename gtl_if<
typename is_segment_concept<
typename geometry_concept<
typename SegmentContainer::value_type
>::type
>::type
>::type
>::type,
void
>::type
intersect_segments(
SegmentContainer& result,
SegmentIterator first,
SegmentIterator last) {
typedef typename SegmentContainer::value_type segment_type;
typedef typename segment_traits<segment_type>::coordinate_type Unit;
typedef typename scanline_base<Unit>::Point Point;
typedef typename scanline_base<Unit>::half_edge half_edge;
typedef int segment_id;
std::vector<std::pair<half_edge, segment_id> > half_edges;
std::vector<std::pair<half_edge, segment_id> > half_edges_out;
segment_id id_in = 0;
half_edges.reserve(std::distance(first, last));
for (; first != last; ++first) {
Point l, h;
assign(l, low(*first));
assign(h, high(*first));
half_edges.push_back(std::make_pair(half_edge(l, h), id_in++));
}
half_edges_out.reserve(half_edges.size());
// Apparently no need to pre-sort data when calling validate_scan.
if (half_edges.size() != 0) {
line_intersection<Unit>::validate_scan(
half_edges_out, half_edges.begin(), half_edges.end());
}
result.reserve(result.size() + half_edges_out.size());
for (std::size_t i = 0; i < half_edges_out.size(); ++i) {
Point l = half_edges_out[i].first.first;
Point h = half_edges_out[i].first.second;
result.push_back(construct<segment_type>(l, h));
}
}
template <typename Rectangle, typename SegmentIterator>
typename enable_if<
typename gtl_and<
typename gtl_if<
typename is_rectangle_concept<
typename geometry_concept<Rectangle>::type
>::type
>::type,
typename gtl_if<
typename is_segment_concept<
typename geometry_concept<
typename std::iterator_traits<SegmentIterator>::value_type
>::type
>::type
>::type
>::type,
bool
>::type
envelope_segments(
Rectangle& rect,
SegmentIterator first,
SegmentIterator last) {
for (SegmentIterator it = first; it != last; ++it) {
if (it == first) {
set_points(rect, low(*it), high(*it));
} else {
encompass(rect, low(*it));
encompass(rect, high(*it));
}
}
return first != last;
}
} // polygon
} // boost
#endif // BOOST_POLYGON_SEGMENT_UTILS_HPP