changes.txt

add these at end of ransac

    if(a_gl >= img.cols/2 && (a_gl + w_gl) >= img.cols/2)
    w_gl = 10001;
    if(a_gl < img.cols/2 && (a_gl + w_gl) < img.cols/2)
    w_gl = 10002;

    if (fabs(w_gl) < 225) w_gl = 10003;

//detecting horizontal lanes
vector<Vec4i> lines;
HoughLinesP(mario, lines,1, CV_PI/180, 80, 30, 10);

for (int i = 0; i < lines.size(); i++) {
double angle = atan(lines[i][1] - lines[i][3])/(lines[i][0] - lines[i][2]);
if (fabs(angle) < degree_for_horizontal*PI/180) {
    way.clear();
    if (is_prev_single_left) {
	way.push_back(3*mario.cols/4);
	way.push_back(mario.rows - (lines[i][1] + mario.rows)/2);
	way.push_back(0);
	break;
    }
    else {
	way.push_back(mario.cols/4);
	way.push_back(mario.rows - (lines[i][1] + mario.rows)/2);
	way.push_back(PI);
	break;
    }
}
}

change centroid function to this:

Point centroid(Mat img, double a, double lam)
{

    double sum_x = 0;
    int no_of_x = 0;
    for (int j = 0; j < img.rows; j++) {
	float y = img.rows-j;
	float x = y*y/lam + a;
	if (x < 0 || x >= img.cols) continue;
	sum_x += x;
	no_of_x++;
    }

    Point centroid;
    centroid.x = sum_x/no_of_x;
    centroid.y = img.rows/2;
    return centroid;		
}