123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131 |
- /*
- Copyright 2008 Intel Corporation
- 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).
- */
- namespace boost { namespace polygon { namespace detail {
- template <typename coordinate_type>
- struct minkowski_offset {
- typedef point_data<coordinate_type> point;
- typedef polygon_set_data<coordinate_type> polygon_set;
- typedef polygon_with_holes_data<coordinate_type> polygon;
- typedef std::pair<point, point> edge;
- static void convolve_two_segments(std::vector<point>& figure, const edge& a, const edge& b) {
- figure.clear();
- figure.push_back(point(a.first));
- figure.push_back(point(a.first));
- figure.push_back(point(a.second));
- figure.push_back(point(a.second));
- convolve(figure[0], b.second);
- convolve(figure[1], b.first);
- convolve(figure[2], b.first);
- convolve(figure[3], b.second);
- }
- template <typename itrT1, typename itrT2>
- static void convolve_two_point_sequences(polygon_set& result, itrT1 ab, itrT1 ae, itrT2 bb, itrT2 be) {
- if(ab == ae || bb == be)
- return;
- point first_a = *ab;
- point prev_a = *ab;
- std::vector<point> vec;
- polygon poly;
- ++ab;
- for( ; ab != ae; ++ab) {
- point first_b = *bb;
- point prev_b = *bb;
- itrT2 tmpb = bb;
- ++tmpb;
- for( ; tmpb != be; ++tmpb) {
- convolve_two_segments(vec, std::make_pair(prev_b, *tmpb), std::make_pair(prev_a, *ab));
- set_points(poly, vec.begin(), vec.end());
- result.insert(poly);
- prev_b = *tmpb;
- }
- prev_a = *ab;
- }
- }
- template <typename itrT>
- static void convolve_point_sequence_with_polygons(polygon_set& result, itrT b, itrT e, const std::vector<polygon>& polygons) {
- for(std::size_t i = 0; i < polygons.size(); ++i) {
- convolve_two_point_sequences(result, b, e, begin_points(polygons[i]), end_points(polygons[i]));
- for(typename polygon_with_holes_traits<polygon>::iterator_holes_type itrh = begin_holes(polygons[i]);
- itrh != end_holes(polygons[i]); ++itrh) {
- convolve_two_point_sequences(result, b, e, begin_points(*itrh), end_points(*itrh));
- }
- }
- }
- static void convolve_two_polygon_sets(polygon_set& result, const polygon_set& a, const polygon_set& b) {
- result.clear();
- std::vector<polygon> a_polygons;
- std::vector<polygon> b_polygons;
- a.get(a_polygons);
- b.get(b_polygons);
- for(std::size_t ai = 0; ai < a_polygons.size(); ++ai) {
- convolve_point_sequence_with_polygons(result, begin_points(a_polygons[ai]),
- end_points(a_polygons[ai]), b_polygons);
- for(typename polygon_with_holes_traits<polygon>::iterator_holes_type itrh = begin_holes(a_polygons[ai]);
- itrh != end_holes(a_polygons[ai]); ++itrh) {
- convolve_point_sequence_with_polygons(result, begin_points(*itrh),
- end_points(*itrh), b_polygons);
- }
- for(std::size_t bi = 0; bi < b_polygons.size(); ++bi) {
- polygon tmp_poly = a_polygons[ai];
- result.insert(convolve(tmp_poly, *(begin_points(b_polygons[bi]))));
- tmp_poly = b_polygons[bi];
- result.insert(convolve(tmp_poly, *(begin_points(a_polygons[ai]))));
- }
- }
- }
- };
- }
- template<typename T>
- inline polygon_set_data<T>&
- polygon_set_data<T>::resize(coordinate_type resizing, bool corner_fill_arc, unsigned int num_circle_segments) {
- using namespace ::boost::polygon::operators;
- if(!corner_fill_arc) {
- if(resizing < 0)
- return shrink(-resizing);
- if(resizing > 0)
- return bloat(resizing);
- return *this;
- }
- if(resizing == 0) return *this;
- if(empty()) return *this;
- if(num_circle_segments < 3) num_circle_segments = 4;
- rectangle_data<coordinate_type> rect;
- extents(rect);
- if(resizing < 0) {
- ::boost::polygon::bloat(rect, 10);
- (*this) = rect - (*this); //invert
- }
- //make_arc(std::vector<point_data< T> >& return_points,
- //point_data< double> start, point_data< double> end,
- //point_data< double> center, double r, unsigned int num_circle_segments)
- std::vector<point_data<coordinate_type> > circle;
- point_data<double> center(0.0, 0.0), start(0.0, (double)resizing);
- make_arc(circle, start, start, center, std::abs((double)resizing),
- num_circle_segments);
- polygon_data<coordinate_type> poly;
- set_points(poly, circle.begin(), circle.end());
- polygon_set_data<coordinate_type> offset_set;
- offset_set += poly;
- polygon_set_data<coordinate_type> result;
- detail::minkowski_offset<coordinate_type>::convolve_two_polygon_sets
- (result, *this, offset_set);
- if(resizing < 0) {
- result = result & rect;//eliminate overhang
- result = result ^ rect;//invert
- }
- *this = result;
- return *this;
- }
- }}
|