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The polygon contains an outer ring and zero or more inner rings.
template<typename Point, bool ClockWise, bool Closed, template< typename, typename > class PointList, template< typename, typename > class RingList, template< typename > class PointAlloc, template< typename > class RingAlloc> class model::polygon { // ... };
| Parameter | Default | Description | 
|---|---|---|
| typename Point | point type | |
| bool ClockWise | true | true for clockwise direction, false for CounterClockWise direction | 
| bool Closed | true | true for closed polygons (last point == first point), false open points | 
| template< typename, typename > class PointList | std::vector | container type for points, for example std::vector, std::list, std::deque | 
| template< typename, typename > class RingList | std::vector | container type for inner rings, for example std::vector, std::list, std::deque | 
| template< typename > class PointAlloc | std::allocator | container-allocator-type, for the points | 
| template< typename > class RingAlloc | std::allocator | container-allocator-type, for the rings | 
| Function | Description | Parameters | 
|---|---|---|
| 
 polygon() 
 | Default constructor, creating an empty polygon. | |
| 
 polygon(std::initializer_list< ring_type > l) 
 | Constructor taking std::initializer_list, filling the polygon. | std::initializer_list< ring_type >: l: | 
| Function | Description | Parameters | Returns | 
|---|---|---|---|
| 
 ring_type const & outer() 
 | |||
| 
 inner_container_type const & inners() 
 | |||
| 
 ring_type & outer() 
 | |||
| 
 inner_container_type & inners() 
 | |||
| 
 void clear() 
 | Utility method, clears outer and inner rings. | 
Either
          #include <boost/geometry/geometries/geometries.hpp>
        
Or
          #include <boost/geometry/geometries/polygon.hpp>
        
Declaration and use of the Boost.Geometry model::polygon, modelling the Polygon Concept
#include <iostream> #include <boost/geometry.hpp> #include <boost/geometry/geometries/geometries.hpp> namespace bg = boost::geometry; int main() { typedef bg::model::point<double, 2, bg::cs::cartesian> point_t; typedef bg::model::polygon<point_t> polygon_t;polygon_t poly1;
#if !defined(BOOST_NO_CXX11_UNIFIED_INITIALIZATION_SYNTAX) \ && !defined(BOOST_NO_CXX11_HDR_INITIALIZER_LIST) polygon_t polygon2{{{0.0, 0.0}, {0.0, 5.0}, {5.0, 5.0}, {5.0, 0.0}, {0.0, 0.0}}, {{1.0, 1.0}, {4.0, 1.0}, {4.0, 4.0}, {1.0, 4.0}, {1.0, 1.0}}};
#endif bg::append(poly1.outer(), point_t(0.0, 0.0));
bg::append(poly1.outer(), point_t(0.0, 5.0)); bg::append(poly1.outer(), point_t(5.0, 5.0)); bg::append(poly1.outer(), point_t(5.0, 0.0)); bg::append(poly1.outer(), point_t(0.0, 0.0)); poly1.inners().resize(1);
bg::append(poly1.inners()[0], point_t(1.0, 1.0));
bg::append(poly1.inners()[0], point_t(4.0, 1.0)); bg::append(poly1.inners()[0], point_t(4.0, 4.0)); bg::append(poly1.inners()[0], point_t(1.0, 4.0)); bg::append(poly1.inners()[0], point_t(1.0, 1.0)); double a = bg::area(poly1); std::cout << a << std::endl; return 0; }
| Default parameters, clockwise, closed polygon. | |
| Default-construct a polygon. | |
| Construct a polygon containing an exterior and interior ring, using C++11 unified initialization syntax. | |
| Append point to the exterior ring. | |
| Resize a container of interior rings. | |
| Append point to the interior ring. | 
Output:
16