ceph/src/boost/libs/geometry/doc/src/examples/algorithms/transform.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 //[transform
  11 //` Shows how points can be transformed using the default strategy
  12
  13 #include <iostream>
  14 #include <boost/geometry.hpp>
  15
  16
  17 int main()
  18 {
  19     namespace bg = boost::geometry;
  20
  21     // Select a point near the pole (theta=5.0, phi=15.0)
  22     bg::model::point<long double, 2, bg::cs::spherical<bg::degree> > p1(15.0, 5.0);
  23
  24     // Transform from degree to radian. Default strategy is automatically selected,
  25     // it will convert from degree to radian
  26     bg::model::point<long double, 2, bg::cs::spherical<bg::radian> > p2;
  27     bg::transform(p1, p2);
  28
  29     // Transform from degree (lon-lat) to 3D (x,y,z). Default strategy is automatically selected,
  30     // it will consider points on a unit sphere
  31     bg::model::point<long double, 3, bg::cs::cartesian> p3;
  32     bg::transform(p1, p3);
  33
  34     std::cout
  35         << "p1: " << bg::dsv(p1) << std::endl
  36         << "p2: " << bg::dsv(p2) << std::endl
  37         << "p3: " << bg::dsv(p3) << std::endl;
  38
  39     return 0;
  40 }
  41
  42 //]
  43
  44
  45 //[transform_output
  46 /*`
  47 Output:
  48 [pre
  49 p1: (15, 5)
  50 p2: (0.261799, 0.0872665)
  51 p3: (0.084186, 0.0225576, 0.996195)
  52 ]
  53 */
  54 //]