OpenCV系列(18)|三角剖分

#include <opencv2/imgproc.hpp>
#include <opencv2/highgui.hpp>
#include <iostream>
#include <fstream>
using namespace cv;
using namespace std;

static void help()
{
    cout << "\nThis program demonstrates iterative construction of\n"
           "delaunay triangulation and voronoi tessellation.\n"
           "It draws a random set of points in an image and then delaunay triangulates them.\n"
           "Usage: \n"
           "./delaunay \n"
           "\nThis program builds the triangulation interactively, you may stop this process by\n"
           "hitting any key.\n";
}
//画出三角剖分的顶点
static void draw_subdiv_point( Mat& img, Point2f fp, Scalar color )
{
    circle( img, fp, 3, color, FILLED, LINE_8, 0 );
}
//画出三角剖分的边
static void draw_subdiv( Mat& img, Subdiv2D& subdiv, Scalar delaunay_color )
{
#if 1
    vector<Vec6f> triangleList;
    subdiv.getTriangleList(triangleList);
    vector<Point> pt(3);

    for( size_t i = 0; i < triangleList.size(); i++ )
    {
        Vec6f t = triangleList[i];
        pt[0] = Point(cvRound(t[0]), cvRound(t[1]));
        pt[1] = Point(cvRound(t[2]), cvRound(t[3]));
        pt[2] = Point(cvRound(t[4]), cvRound(t[5]));
        line(img, pt[0], pt[1], delaunay_color, 1, LINE_AA, 0);
        line(img, pt[1], pt[2], delaunay_color, 1, LINE_AA, 0);
        line(img, pt[2], pt[0], delaunay_color, 1, LINE_AA, 0);
    }
#else
    vector<Vec4f> edgeList;
    subdiv.getEdgeList(edgeList);
    for( size_t i = 0; i < edgeList.size(); i++ )
    {
        Vec4f e = edgeList[i];
        Point pt0 = Point(cvRound(e[0]), cvRound(e[1]));
        Point pt1 = Point(cvRound(e[2]), cvRound(e[3]));
        line(img, pt0, pt1, delaunay_color, 1, LINE_AA, 0);
    }
#endif
}

//画出voronoi面
static void paint_voronoi( Mat& img, Subdiv2D& subdiv )
{
    vector<vector<Point2f> > facets;
    vector<Point2f> centers;
    subdiv.getVoronoiFacetList(vector<int>(), facets, centers);

    vector<Point> ifacet;
    vector<vector<Point> > ifacets(1);

    for( size_t i = 0; i < facets.size(); i++ )
    {
        ifacet.resize(facets[i].size());
        for( size_t j = 0; j < facets[i].size(); j++ )
            ifacet[j] = facets[i][j];

        Scalar color;
        color[0] = rand() & 255;
        color[1] = rand() & 255;
        color[2] = rand() & 255;
        fillConvexPoly(img, ifacet, color, 8, 0);

        ifacets[0] = ifacet;
        polylines(img, ifacets, true, Scalar(), 1, LINE_AA, 0);
        circle(img, centers[i], 3, Scalar(), FILLED, LINE_AA, 0);
    }
}


int main( int argc, char** argv )
{
    cv::CommandLineParser parser(argc, argv, "{help h||}");
    if (parser.has("help"))
    {
        help();
        return 0;
    }
    
    Scalar active_facet_color(0, 0, 255), delaunay_color(255,255,255);
    Mat img = imread("tt.jpg");
    Mat img_ori = img.clone();
    Size size = img.size();
    Rect rect(0, 0,size.width,size.height);//外接边界盒子

    Subdiv2D subdiv(rect);//细分

    string win = "Delaunay Demo";
  
    //点集
    vector<Point2f> points;
    std::ifstream ifs("face.txt");
    int x, y;
    while(ifs >> x >>y)
    {
        points.push_back(Point2f(x,y));
    }

    for( vector<Point2f>::iterator it = points.begin(); it != points.end(); it++)
    {
        subdiv.insert(*it);
       
        Mat img_copy = img_ori.clone();
        // 画三角剖分
        draw_subdiv( img_copy, subdiv, delaunay_color );
        imshow(win, img_copy);
        waitKey(1000);
    }
    
    draw_subdiv( img, subdiv, delaunay_color );

    //画点
    for( vector<Point2f>::iterator it = points.begin(); it != points.end(); it++)
    {
        draw_subdiv_point(img, *it, active_facet_color);
    }

    Mat img_voronoi = Mat::zeros(img.rows, img.cols, CV_8UC3);
    paint_voronoi( img_voronoi, subdiv );
    imshow(win, img_voronoi );
    waitKey(0);

    return 0;
}