Visulalize Boost Voronoi in OpenSceneGraph

/*
*    Copyright (c) 2014 eryar All Rights Reserved.
*
*        File    : Main.cpp
*        Author  : eryar@163.com
*        Date    : 2014-05-06 18:28
*        Version : V1.0
*
*    Description : The Simplest example for boost voronoi library.
*      Key words : boost voronoi, C++
*
*/

#include \"boost/polygon/voronoi.hpp\"

using namespace boost::polygon;

typedef int coordinate_type;
typedef point_data<coordinate_type> Point;
typedef voronoi_diagram<double> VD;

int main(int argc, char* argv[])
{
    std::vector<Point> points;

    points.push_back(Point(0, 0));
    points.push_back(Point(1, 6));
    points.push_back(Point(-4, 5));
    points.push_back(Point(5, -1));
    points.push_back(Point(3, -11));
    points.push_back(Point(13, -1));

    VD vd;
    construct_voronoi(points.begin(), points.end(), &vd);

    return 0;
}

/*
*    Copyright (c) 2014 eryar All Rights Reserved.
*
*        File    : Main.cpp
*        Author  : eryar@163.com
*        Date    : 2014-05-06 18:28
*        Version : V1.0
*
*    Description : VoronoiViewer for boost voronoi library visulization.
*      Key words : boost voronoi, C++, OpenSceneGraph
*
*/

#include <osgViewer/Viewer>
#include <osgGA/StateSetManipulator>
#include <osgViewer/ViewerEventHandlers>

#pragma comment(lib, \"osgd.lib\")
#pragma comment(lib, \"osgDBd.lib\")
#pragma comment(lib, \"osgGAd.lib\")
#pragma comment(lib, \"osgViewerd.lib\")


#include \"boost/polygon/voronoi.hpp\"

using namespace boost::polygon;

typedef double coordinate_type;
typedef point_data<coordinate_type> Point;
typedef voronoi_diagram<coordinate_type> VD;


osg::Node* BuildVoronoiDiagram(void)
{
    srand(static_cast<unsigned int> (time(NULL)));

    osg::ref_ptr<osg::Geode> theGeode = new osg::Geode();
    osg::ref_ptr<osg::Geometry> theLines = new osg::Geometry();
    osg::ref_ptr<osg::Vec3Array> theVertices = new osg::Vec3Array();

    VD vd;
    std::vector<Point> thePoints;

    // Add points for the Voronoi Diagram.
    for (int i = 0; i < 100; ++i)
    {
        int x = rand() % 100;
        int y = rand() % 100;

        thePoints.push_back(Point(x, y));

        // Display the site of the Voronoi Diagram.
        theVertices->push_back(osg::Vec3(x - 1, 0.0, y));
        theVertices->push_back(osg::Vec3(x + 1, 0.0, y));

        theVertices->push_back(osg::Vec3(x, 0.0, y - 1));
        theVertices->push_back(osg::Vec3(x, 0.0, y + 1));
    }

    construct_voronoi(thePoints.begin(), thePoints.end(), &vd);

    // Visualize the edge of the Voronoi Diagram.
    // Traversing Voronoi edges using edge iterator.
    for (VD::const_edge_iterator it = vd.edges().begin(); it != vd.edges().end(); ++it)
    {
        if (it->is_primary())
        {
            if (it->is_finite())
            {
                theVertices->push_back(osg::Vec3(it->vertex0()->x(), 0.0, it->vertex0()->y()));
                theVertices->push_back(osg::Vec3(it->vertex1()->x(), 0.0, it->vertex1()->y()));
            }
            else
            {
                Point p1 = thePoints[it->cell()->source_index()];
                Point p2 = thePoints[it->twin()->cell()->source_index()];
                Point origin;
                Point direction;
                coordinate_type koef = 1.0;

                origin.x((p1.x() + p2.x()) * 0.5);
                origin.y((p1.y() + p2.y()) * 0.5);

                direction.x(p1.y() - p2.y());
                direction.y(p2.x() - p1.x());

                if (it->vertex0() == NULL)
                {
                    theVertices->push_back(osg::Vec3(
                        origin.x() - direction.x() * koef, 
                        0.0,
                        origin.y() - direction.y() * koef));
                }
                else
                {
                    theVertices->push_back(osg::Vec3(it->vertex0()->x(), 0.0, it->vertex0()->y()));
                }

                if (it->vertex1() == NULL)
                {
                    theVertices->push_back(osg::Vec3(
                        origin.x() + direction.x() * koef, 
                        0.0,
                        origin.y() + direction.y() * koef));
                }
                else
                {
                    theVertices->push_back(osg::Vec3(it->vertex1()->x(), 0.0, it->vertex1()->y()));
                }
            }
        }
    }
    
    theLines->setVertexArray(theVertices);

    // Set the colors.
    osg::ref_ptr<osg::Vec4Array> theColors = new osg::Vec4Array();
    theColors->push_back(osg::Vec4(1.0f, 1.0f, 0.0f, 1.0f));

    theLines->setColorArray(theColors);
    theLines->setColorBinding(osg::Geometry::BIND_OVERALL);

    // Set the normal.
    osg::ref_ptr<osg::Vec3Array> theNormals = new osg::Vec3Array();
    theNormals->push_back(osg::Vec3(0.0f, -1.0f, 0.0f));

    theLines->setNormalArray(theNormals);
    theLines->setNormalBinding(osg::Geometry::BIND_OVERALL);

    theLines->addPrimitiveSet(new osg::DrawArrays(osg::PrimitiveSet::LINES, 0, theVertices->size()));
    
    theGeode->addDrawable(theLines);

    return theGeode.release();
}


int main(int argc, char *argv[])
{
    osgViewer::Viewer theViewer;

    theViewer.setSceneData(BuildVoronoiDiagram());
    theViewer.addEventHandler(new osgGA::StateSetManipulator(theViewer.getCamera()->getOrCreateStateSet()));
    theViewer.addEventHandler(new osgViewer::StatsHandler);
    theViewer.addEventHandler(new osgViewer::WindowSizeHandler);

    return theViewer.run();
}