...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
get coordinate value of a Box or Segment
The free functions get and set are two of the most important functions of Boost.Geometry, both within the library, as also for the library user. With these two functions you normally get and set coordinate values from and for a point, box, segment or sphere.
template<std::size_t Index, std::size_t Dimension, typename Geometry> coordinate_type<Geometry>::type get(Geometry const & geometry)
Type |
Concept |
Name |
Description |
---|---|---|---|
Index |
Index, this template parameter is required. For a Box: either min_corner or max_corner. For a Segment: either 0 or 1 for first or last point. |
- |
Must be specified |
Dimension |
Dimension, this template parameter is required. Should contain [0 .. n-1] for an n-dimensional geometry |
- |
Must be specified |
Geometry const & |
Any type fulfilling a Box Concept or a Segment Concept |
geometry |
A model of the specified concept |
coordinate value
Either
#include <boost/geometry.hpp>
Or
#include <boost/geometry/core/access.hpp>
Case |
Behavior |
---|---|
Box |
Returns the coordinate of a box (use min_corner, max_corner to specify which of the points to get) |
Segment |
Returns the coordinate of a segment (use 0, 1 to specify which of the two points to get) |
Constant
Get the coordinate of a box
#include <iostream> #include <boost/geometry.hpp> #include <boost/geometry/geometries/point_xy.hpp> namespace bg = boost::geometry; int main() { bg::model::box<bg::model::d2::point_xy<double> > box; bg::assign_values(box, 1, 3, 5, 6); std::cout << "Box:" << " " << bg::get<bg::min_corner, 0>(box) << " " << bg::get<bg::min_corner, 1>(box) << " " << bg::get<bg::max_corner, 0>(box) << " " << bg::get<bg::max_corner, 1>(box) << std::endl; return 0; }
Output:
Box: 1 3 5 6