// the vecotr that holds all input points
std::vector<Point2d> inputPoints;

// initialize edge points with any point in the point set
Point2d mostTopPoint = inputPoints[0];
Point2d mostRightPoint = inputPoints[0];
Point2d mostBottomPoint = inputPoints[0];
Point2d mostLeftPoint = inputPoints[0];


// first loop over all points from first to last
for(unsigned int i = 0; i < inputPoints.size(); ++i)
{
    // the current point that is checked
    Point2d currentPoint = inputPoints[i];

    // check if the point is more top than any other found point
    if(currentPoint.y < mostTopPoint.y)
        mostTopPoint = currentPoint;

    // check if the point is more right than any other found point
    if(currentPoint.x > mostRightPoint.x)
        mostRightPoint = currentPoint;

    // check if the point is more bottom than any other found point
    if(currentPoint.y > mostBottomPoint.y)
        mostBottomPoint = currentPoint;

    // check if the point is more left than any other found point
    if(currentPoint.x < mostLeftPoint.x)
        mostLeftPoint = currentPoint;

}

// now the most top/right/bottom/left point should have been found

// still have to find out which is which corner
Point2d upLeftCorner;
Point2d upRightCorner;
Point2d lowRightCorner;
Point2d lowLeftCorner;



// if the mostLeftPoint y coordinate is smaller than the mostRightCorner y coordinate
// --> the checkerboard is tilted to right (viewers point)
// --> means most mostTopPoint must be the upLeftCorner
if(mostLeftPoint.y < mostRightPoint.y)
{
    upLeftCorner = mostTopPoint;
    // also means the mostRightPoint is the upRightCorner
    upRightCorner = mostRightPoint;
    // also means the mostBottomPoint is the lowRightCorner
    lowRightCorner = mostBottomPoint;
    // also means the mostLeftPoint must be the lowLeftCorner
    lowLeftCorner = mostLeftPoint;
}
// otherwise it is tilted to left (viewers point)
// --> means mostLeftPoint is the upLeftCorner
else
{
    upLeftCorner = mostLeftPoint;
    // also means the mostTopPoint is the upRightCorner
    upRightCorner = mostTopPoint;
    // also means the mostRightPoint is the lowRightCorner
    lowRightCorner = mostRightPoint;
    // also means the mostBottomPoint must be the lowLeftCorner
    lowLeftCorner = mostBottomPoint;
}