Converting convexHull Points Into Points I Can Use

Question

I'm using Visual C++ 2010 Express with OpenCV, and I'm trying to track two hands. So far I already have the convexHull and convexityDefects, but I'm having trouble getting the points of the convexHull. I'd like to use them to draw a line from the center of each hand (a point I already can draw lines with) to each convexHull point, and then I can add filters on that so it only picks the ones for fingers. That's no problem, I just need to get the hull points into a working format for drawing functions. My code currently looks like this:

findContours(temp,Lcontours,hierarchy,CV_RETR_CCOMP,CV_CHAIN_APPROX_SIMPLE );
vector<vector<int> >hullI( Lcontours.size() );
vector<vector<Point> >hullP( Lcontours.size() );
vector<vector<Vec4i>> defects( Lcontours.size() );
std::sort(Lcontours.begin(), Lcontours.end(),compare_contour_areas);

for( int f = 0; f < Lcontours.size(); f++ ){
    convexHull( Mat(Lcontours[f]), hullI[f], true );
    convexHull( Mat(Lcontours[f]), hullP[f], true );
    convexityDefects(Lcontours[f],hullI[f],defects[f]);
    drawContours(cameraFeed(lefT), Lcontours, 0, Scalar(0,200,200), 1.5, 8, vector<Vec4i>(), 0, Point() );
    drawContours(cameraFeed(lefT), hullP, 0, Scalar(200,200,0), 1.5, 8, vector<Vec4i>(), 0, Point() );

How do I convert the hull vector (it doesn't matter which one, hullI for int or hullP for point formats) into something I can say "print the x and y of hull[f]" about. So far it seems to be like hull[?][?][?][?] because it's vector within vector or something? Does this have to do with the end of the convexHull functions, where the last parameter is either true or false?

Answer 1

for( int f = 0; f < Lcontours.size(); f++ ){
    convexHull( Mat(Lcontours[f]), hullI[f], true );
    convexHull( Mat(Lcontours[f]), hullP[f], true );

    vector <Point> thisHull(hullP[f].size());
    thisHull=hullP[f]; //which hull you want to look at
    int pointYouWant; //point you want to interrogate

    cout<<"for hull #"<< f << ", point #" << pointYouWant << " , x= " << thisHull[pointYouWant].x << " , y= " << thisHull[pointYouWant].y << endl;
    }