1 // Boost.Geometry (aka GGL, Generic Geometry Library)
2 // QuickBook Example
3
4 // Copyright (c) 2013, 2014 Barend Gehrels, Amsterdam, the Netherlands.
5
6 // Use, modification and distribution is subject to the Boost Software License,
7 // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
8 // http://www.boost.org/LICENSE_1_0.txt)
9
10 //[buffer_with_strategies
11 //` Shows how the buffer algorithm can be used to create a buffer of a linestring, a multi point, a multi polygon
12
13 #include <boost/geometry.hpp>
14 #include <boost/geometry/geometries/point_xy.hpp>
15 #include <boost/geometry/geometries/geometries.hpp>
16 /*<-*/ #include "../examples_utils/create_svg_buffer.hpp" /*->*/
17
main()18 int main()
19 {
20 typedef double coordinate_type;
21 typedef boost::geometry::model::d2::point_xy<coordinate_type> point;
22 typedef boost::geometry::model::polygon<point> polygon;
23
24 // Declare strategies
25 const double buffer_distance = 1.0;
26 const int points_per_circle = 36;
27 boost::geometry::strategy::buffer::distance_symmetric<coordinate_type> distance_strategy(buffer_distance);
28 boost::geometry::strategy::buffer::join_round join_strategy(points_per_circle);
29 boost::geometry::strategy::buffer::end_round end_strategy(points_per_circle);
30 boost::geometry::strategy::buffer::point_circle circle_strategy(points_per_circle);
31 boost::geometry::strategy::buffer::side_straight side_strategy;
32
33 // Declare output
34 boost::geometry::model::multi_polygon<polygon> result;
35
36 // Declare/fill a linestring
37 boost::geometry::model::linestring<point> ls;
38 boost::geometry::read_wkt("LINESTRING(0 0,4 5,7 4,10 6)", ls);
39
40 // Create the buffer of a linestring
41 boost::geometry::buffer(ls, result,
42 distance_strategy, side_strategy,
43 join_strategy, end_strategy, circle_strategy);
44 /*<-*/ create_svg_buffer("buffer_linestring.svg", ls, result); /*->*/
45
46 // Declare/fill a multi point
47 boost::geometry::model::multi_point<point> mp;
48 boost::geometry::read_wkt("MULTIPOINT((3 3),(4 4),(6 2))", mp);
49
50 // Create the buffer of a multi point
51 boost::geometry::buffer(mp, result,
52 distance_strategy, side_strategy,
53 join_strategy, end_strategy, circle_strategy);
54 /*<-*/ create_svg_buffer("buffer_multi_point.svg", mp, result); /*->*/
55
56 // Declare/fill a multi_polygon
57 boost::geometry::model::multi_polygon<polygon> mpol;
58 boost::geometry::read_wkt("MULTIPOLYGON(((0 1,2 5,5 3,0 1)),((1 1,5 2,5 0,1 1)))", mpol);
59
60 // Create the buffer of a multi polygon
61 boost::geometry::buffer(mpol, result,
62 distance_strategy, side_strategy,
63 join_strategy, end_strategy, circle_strategy);
64 /*<-*/ create_svg_buffer("buffer_multi_polygon.svg", mpol, result); /*->*/
65
66 return 0;
67 }
68
69 //]
70
71