(C++) BoostGeometryExample11

 

 

Boost.Geometry example 11: Create a polygon from two intersecting polygons is a Boost.Geometry example.

Technical facts

 

Application type(s)

• Desktop application

Operating system(s) or programming environment(s)

• Lubuntu 15.04 (vivid)

IDE(s):

• Qt Creator 3.1.1

Project type:

• GUI application

C++ standard:

• C++11

Compiler(s):

• G++ 4.9.2

Libraries used:

• Qt: version 5.4.1 (32 bit)
• STL: GNU ISO C++ Library, version 4.9.2

 

 

 

 

 

Qt project file: ./CppBoostGeometryExample11/CppBoostGeometryExample11.pro

 

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exists(../../ConsoleApplication.pri) {   include(../../ConsoleApplication.pri) } !exists(../../ConsoleApplication.pri) {   QT += core   QT += gui   greaterThan(QT_MAJOR_VERSION, 4): QT += widgets   CONFIG   += console   CONFIG   -= app_bundle   TEMPLATE = app   CONFIG(release, debug|release) {     DEFINES += NDEBUG NTRACE_BILDERBIKKEL   }   QMAKE_CXXFLAGS += -std=c++11 -Wall -Wextra -Weffc++   unix {     QMAKE_CXXFLAGS += -Werror   } } exists(../../Libraries/Boost.pri) {   include(../../Libraries/Boost.pri) } !exists(../../Libraries/Boost.pri) {   win32 {     INCLUDEPATH += \       ../../Libraries/boost_1_55_0   } } SOURCES += main.cpp

 

 

 

 

 

./CppBoostGeometryExample11/main.cpp

 

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#include <cassert> #include <iostream> #include <vector> #pragma GCC diagnostic push #pragma GCC diagnostic ignored "-Weffc++" #pragma GCC diagnostic ignored "-Wunused-local-typedefs" #pragma GCC diagnostic ignored "-Wunused-variable" #include <boost/geometry.hpp> #include <boost/geometry/algorithms/intersection.hpp> #include <boost/geometry/geometries/point_xy.hpp> #include <boost/geometry/geometries/polygon.hpp> #include <boost/geometry/io/wkt/read.hpp> #include <boost/geometry/io/wkt/write.hpp> #include <boost/geometry/io/wkt/wkt.hpp> #pragma GCC diagnostic pop /*    +   *---*    |   |   |    + *-+-* |    | | | | |    + | *-+-*    | |   |    + *---*    |    +-+-+-+-+-+ */ int main() {   typedef boost::geometry::model::d2::point_xy<double> Coordinat2D;   typedef boost::geometry::model::polygon<Coordinat2D> Polygon;   typedef std::vector<Polygon> Polygons;   Polygon polygon_a;   boost::geometry::read_wkt(     "POLYGON((1.0 1.0 , 1.0 3.0 , 3.0 3.0 , 3.0 1.0))",     polygon_a   );   boost::geometry::correct(polygon_a);   Polygon polygon_b;   boost::geometry::read_wkt(     "POLYGON((2.0 2.0 , 2.0 4.0 , 4.0 4.0 , 4.0 2.0))",     polygon_b   );   boost::geometry::correct(polygon_b);   Polygons polygons;   boost::geometry::intersection(polygon_a,polygon_b,polygons);   assert(polygons.size() == 1);   const auto polygon_found = polygons[0];   Polygon polygon_expected;   boost::geometry::read_wkt(     "POLYGON((2.0 2.0, 2.0 3.0, 3.0 3.0, 3.0 2.0))",     polygon_expected   );   boost::geometry::correct(polygon_expected);   std::cout     << "Found:" << '\n'     << "As WKT: " << boost::geometry::wkt<Polygon>(polygon_found) << '\n'     << "#points: " << polygon_found.outer().size() << '\n';   for (auto point: polygon_found.outer())   {     std::cout << '(' << boost::geometry::get<0>(point)       << ',' << boost::geometry::get<1>(point) << ')'       << '\n'     ;   }   std::cout     << "Expected:" << '\n'     << "As WKT: " << boost::geometry::wkt<Polygon>(polygon_expected) << '\n'     << "#points: " << polygon_expected.outer().size() << '\n';   for (auto point: polygon_expected.outer())   {     std::cout << '(' << boost::geometry::get<0>(point)       << ',' << boost::geometry::get<1>(point) << ')'       << '\n'     ;   }   assert(polygon_found.outer().size() == polygon_expected.outer().size());   assert(boost::geometry::equals(polygon_found,polygon_expected)); } /* Screen output: Found: As WKT: POLYGON((2 3,3 3,3 2,2 2,2 3)) #points: 5 (2,3) (3,3) (3,2) (2,2) (2,3) Expected: As WKT: POLYGON((2 2,2 3,3 3,3 2,2 2)) #points: 5 (2,2) (2,3) (3,3) (3,2) (2,2) Press <RETURN> to close this window... */