...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
A linestring (named so by OGC) is a collection (default a vector) of points.
template<typename Point, template< typename, typename > class Container, template< typename > class Allocator> class model::linestring : public Container< Point, Allocator< Point > > { // ... };
Parameter |
Default |
Description |
---|---|---|
typename Point |
Any type fulfilling a Point Concept |
|
template< typename, typename > class Container |
std::vector |
container type, for example std::vector, std::deque |
template< typename > class Allocator |
std::allocator |
container-allocator-type |
Function |
Description |
Parameters |
---|---|---|
linestring()
|
Default constructor, creating an empty linestring. |
|
template<typename Iterator> linestring(Iterator begin, Iterator end)
|
Constructor with begin and end, filling the linestring. |
Iterator: begin: Iterator: end: |
linestring(std::initializer_list< Point > l)
|
Constructor taking std::initializer_list, filling the linestring. |
std::initializer_list< Point >: l: |
Either
#include <boost/geometry/geometries/geometries.hpp>
Or
#include <boost/geometry/geometries/linestring.hpp>
Declaration and use of the Boost.Geometry model::linestring, modelling the Linestring 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::linestring<point_t> linestring_t; linestring_t ls1; #if !defined(BOOST_NO_CXX11_UNIFIED_INITIALIZATION_SYNTAX) \ && !defined(BOOST_NO_CXX11_HDR_INITIALIZER_LIST) linestring_t ls2{{0.0, 0.0}, {1.0, 0.0}, {1.0, 2.0}}; #endif bg::append(ls1, point_t(0.0, 0.0)); bg::append(ls1, point_t(1.0, 0.0)); bg::append(ls1, point_t(1.0, 2.0)); double l = bg::length(ls1); std::cout << l << std::endl; return 0; }
Default-construct a linestring. |
|
Construct a linestring containing three points, using C++11 unified initialization syntax. |
|
Append point. |
Output:
3