ceph/src/boost/libs/geometry/doc/src/examples/algorithms/simplify_insert_with_strategy.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_inserter
  11 //` Simplify a linestring using an output iterator
  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 int main()
  20 {
  21     typedef boost::geometry::model::d2::point_xy<double> P;
  22     typedef boost::geometry::model::linestring<P> L;
  23
  24     L line;
  25     boost::geometry::read_wkt("linestring(1.1 1.1, 2.5 2.1, 3.1 3.1, 4.9 1.1, 3.1 1.9)", line);
  26
  27     typedef boost::geometry::strategy::distance::projected_point<P, P> DS;
  28     typedef boost::geometry::strategy::simplify::douglas_peucker<P, DS> simplification;
  29
  30     L simplified;
  31     boost::geometry::simplify_inserter(line, std::back_inserter(simplified), 0.5, simplification()); //std::ostream_iterator<P>(std::cout, "\n"), 0.5);//);
  32     //std::cout << simplified[0];
  33     //boost::geometry::simplify_inserter(line, std::ostream_iterator<P>(std::cout, "\n"), 0.5);//, simplification());
  34
  35     std::ostream_iterator<P> out(std::cout, "\n");
  36     std::copy(simplified.begin(), simplified.end(), out);
  37
  38     std::cout
  39         << "  original: " << boost::geometry::dsv(line) << std::endl
  40         << "simplified: " << boost::geometry::dsv(simplified) << std::endl;
  41
  42     return 0;
  43 }
  44
  45 //]
  46
  47
  48 //[simplify_inserter_output
  49 /*`
  50 Output:
  51 [pre
  52 simplify_inserter: 16
  53 simplify_inserter: 0.339837
  54 ]
  55 */
  56 //]
  57 /*
  58 OUTPUT
  59 POINT(1.1 1.1)  original: ((1.1, 1.1), (2.5, 2.1), (3.1, 3.1), (4.9, 1.1), (3.1, 1.9))
  60 simplified: ((1.1, 1.1), (3.1, 3.1), (4.9, 1.1), (3.1, 1.9))
  61 */
  62 /*
  63 OUTPUT
  64 POINT(1.1 1.1)  original: ((1.1, 1.1), (2.5, 2.1), (3.1, 3.1), (4.9, 1.1), (3.1, 1.9))
  65 simplified: ((1.1, 1.1), (3.1, 3.1), (4.9, 1.1), (3.1, 1.9))
  66 */
  67 /*
  68 OUTPUT
  69 POINT(1.1 1.1)  original: ((1.1, 1.1), (2.5, 2.1), (3.1, 3.1), (4.9, 1.1), (3.1, 1.9))
  70 simplified: ((1.1, 1.1), (3.1, 3.1), (4.9, 1.1), (3.1, 1.9))
  71 */