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Calculates the envelope (with strategy) of a geometry.
The free function envelope calculates the envelope (also known as axis aligned bounding box, aabb, or minimum bounding rectangle, mbr) of a geometry.
template<typename Geometry, typename Box, typename Strategy> void envelope(Geometry const & geometry, Box & mbr, Strategy const & strategy)
| Type | Concept | Name | Description | 
|---|---|---|---|
| Geometry const & | Any type fulfilling a Geometry Concept | geometry | A model of the specified concept | 
| Box & | Any type fulfilling a Box Concept | mbr | A model of the specified Box Concept which is set to the envelope | 
| Strategy const & | Any type fulfilling a Envelope Strategy Concept | strategy | The strategy which will be used for envelope calculations | 
Either
            #include <boost/geometry.hpp>
          
Or
            #include <boost/geometry/algorithms/envelope.hpp>
          
The function envelope implements function Envelope from the OGC Simple Feature Specification.
Shows how to calculate the bounding box of a polygon
#include <iostream> #include <boost/geometry.hpp> #include <boost/geometry/geometries/box.hpp> #include <boost/geometry/geometries/point_xy.hpp> #include <boost/geometry/geometries/polygon.hpp> int main() { typedef boost::geometry::model::d2::point_xy<double> point; boost::geometry::model::polygon<point> polygon; boost::geometry::read_wkt( "POLYGON((2 1.3,2.4 1.7,2.8 1.8,3.4 1.2,3.7 1.6,3.4 2,4.1 3,5.3 2.6,5.4 1.2,4.9 0.8,2.9 0.7,2 1.3)" "(4.0 2.0, 4.2 1.4, 4.8 1.9, 4.4 2.2, 4.0 2.0))", polygon); boost::geometry::model::box<point> box; boost::geometry::envelope(polygon, box); std::cout << "envelope:" << boost::geometry::dsv(box) << std::endl; return 0; }
Output:
envelope:((2, 0.7), (5.4, 3))