ceph/src/boost/libs/geometry/doc/src/examples/algorithms/simplify.cpp

   1 // Boost.Geometry (aka GGL, Generic Geometry Library)
   2 // QuickBook Example
   3
   4 // Copyright (c) 2011-2012 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 //[simplify
  11 //` Example showing how to simplify a linestring
  12
  13 #include <iostream>
  14
  15 #include <boost/geometry.hpp>
  16 #include <boost/geometry/geometries/linestring.hpp>
  17 #include <boost/geometry/geometries/point_xy.hpp>
  18
  19 /*< For this example we use Boost.Assign to add points >*/
  20 #include <boost/assign.hpp>
  21
  22 using namespace boost::assign;
  23
  24
  25 int main()
  26 {
  27     typedef boost::geometry::model::d2::point_xy<double> xy;
  28
  29     boost::geometry::model::linestring<xy> line;
  30     line += xy(1.1, 1.1), xy(2.5, 2.1), xy(3.1, 3.1), xy(4.9, 1.1), xy(3.1, 1.9); /*< With Boost.Assign >*/
  31
  32     // Simplify it, using distance of 0.5 units
  33     boost::geometry::model::linestring<xy> simplified;
  34     boost::geometry::simplify(line, simplified, 0.5);
  35     std::cout
  36         << "  original: " << boost::geometry::dsv(line) << std::endl
  37         << "simplified: " << boost::geometry::dsv(simplified) << std::endl;
  38
  39
  40     return 0;
  41 }
  42
  43 //]
  44
  45
  46 //[simplify_output
  47 /*`
  48 Output:
  49 [pre
  50   original: ((1.1, 1.1), (2.5, 2.1), (3.1, 3.1), (4.9, 1.1), (3.1, 1.9))
  51 simplified: ((1.1, 1.1), (3.1, 3.1), (4.9, 1.1), (3.1, 1.9))
  52 ]
  53 */
  54 //]