Boost.Geometry:如何创建简单的多边形数组并将其保存为svg图像？

Question

我看一下名为Boost Geometry的图书库, 我看一下它,但是看不到任何教程,至少有点图形化.所以我想知道是否有人可以帮助提供一个简单的教程来创建一些N随机的poligons(颜色大小和形式随机)并将tham保存为像SVG这样的矢量图像？

Answer 1

所以...解决了它:在谷歌上你可以找到这个旧代码.它不会使用最新的1.47.0升级编译.所以你会尝试修复它,你会在这里找到一些过时的文档...这么长的故事,这里是你要做的工作:

下载3个代码文件boost/geometry/extensions/io/svg/,它们只是标题,所以这里没有wories.

现在你可以编译修复,更新当前的提升代码:

#include <iostream>
#include <fstream>
#include <boost/assign.hpp>

#include <boost/algorithm/string.hpp>
#include <boost/geometry/geometry.hpp>
#include <boost/geometry/io/svg/write_svg.hpp>
#include <boost/geometry/geometries/geometries.hpp>
#include <boost/geometry/algorithms/envelope.hpp>

#include <boost/geometry/io/svg/write_svg.hpp>


template <typename Geometry1, typename Geometry2>
void create_svg(std::string const& filename, Geometry1 const& a, Geometry2 const& b)
{
    typedef typename boost::geometry::point_type<Geometry1>::type point_type;
    std::ofstream svg(filename.c_str());

    boost::geometry::svg_mapper<point_type> mapper(svg, 400, 400);
    mapper.add(a);
    mapper.add(b);

    mapper.map(a, "fill-opacity:0.5;fill:rgb(153,204,0);stroke:rgb(153,204,0);stroke-width:2");
    mapper.map(b, "opacity:0.8;fill:none;stroke:rgb(255,128,0);stroke-width:4;stroke-dasharray:1,7;stroke-linecap:round");
}

int main()
{
    using namespace boost::assign;


    boost::geometry::model::ring<boost::geometry::model::d2::point_xy<double> > ring;
    ring +=
        boost::geometry::model::d2::point_xy<double>(4.0, -0.5), boost::geometry::model::d2::point_xy<double>(3.5, 1.0),
        boost::geometry::model::d2::point_xy<double>(2.0, 1.5), boost::geometry::model::d2::point_xy<double>(3.5, 2.0),
        boost::geometry::model::d2::point_xy<double>(4.0, 3.5), boost::geometry::model::d2::point_xy<double>(4.5, 2.0),
        boost::geometry::model::d2::point_xy<double>(6.0, 1.5), boost::geometry::model::d2::point_xy<double>(4.5, 1.0),
        boost::geometry::model::d2::point_xy<double>(4.0, -0.5);


     boost::geometry::model::box<boost::geometry::model::d2::point_xy<double> > box;
     boost::geometry::envelope(ring, box); 
    std::cout
        << "make_envelope:"
        << boost::geometry::dsv(box)
        << std::endl;

    create_svg("make_envelope.svg", ring, box);
}

这将得出这个:

(不是图像,但是矢量svg文件可在google chrome中打开=))所以这是如何在C++中从vector创建SVG文件=)